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1

Tabe, R. H. "Biochemical studies in plant tissue culture with reference to hyperhydration." Thesis(M.Sc.), CSIR-National Chemical Laboratory, Pune, 2000. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2128.

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2

Wood, Adrian J. "Subcellular analysis of normal and pathological gastrointestinal tissue with specific reference to peroxisomes." Thesis, University of Wolverhampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386569.

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3

Bindon, Keren (Keren Ann). "Carbon partitioning in sugarcane internodal tissue with special reference to the insoluble fraction." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51642.

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Thesis (MSc)--University of Stellenbosch, 2000.<br>ENGLISH ABSTRACT: The changes in carbon allocation to sucrose, hexoses, fibre, starch and respiration were investigated in developing internodes of sugarcane. Radiolabelling studies were conducted on internode 3, 6 and 9 tissue, representing three stages of increasing maturity. It was apparent that a high rate of cycling between triose-phosphate and hexose-phosphate occurred. A maximum of 50% of carbon entering triose-phosphates was returned to hexose-phosphate in internode 3 tissue, and this flux decreased with tissue maturity to 30%. Carbon partitioning into sucrose increased from 34% of total 14C uptake in internode 3, to 61% in internodes 6 and 9. In immature tissue, the protein and fibre components were the dominant competing sinks with sucrose for incoming carbon, to which 14 and 16% of carbon were allocated respectively. Increased carbon allocation to sucrose with tissue maturity, coincided with a decrease in partitioning to fibre. This indicated that previous studies had underestimated total carbon allocation to respiration, since the protein component was not considered. In contrast with earlier work, the respiratory pathway was the strongest competitor with sucrose for incoming carbon, even in mature tissue. Between internodes 3 and 6, carbon allocation to total respiration did not change significantly, but decreased 50% in mature tissue. Starch was a weak competitor with sucrose, for incoming carbon, to which a maximum of 2% of 14Cwas allocated in immature tissue. In cane harvested in early spring, radiolabelled maltose was recovered in internode 3 tissue of ripening cane, indicating that concomitant starch synthesis and degradation occurred. The. redistribution of C-1 and C-6 in starch glucose was analysed following feeding of tissue with [1_14C]_and [6_14C]_glucose. Randomization of label in starch indicated that the pathway for carbon movement into sugarcane plastids for starch synthesis is primarily through the triose-phosphate translocator. Finally, this study indicated that radiolabelling of tissue discs is a suitable experimental system to determine carbon flux in sugarcane. During the 3 h labelling period the rate of 14C02 release became linear, indicating that the system approached isotopic steady state between the external and internal glucose pool; and the respiratory processes involved in CO2 release.<br>AFRIKAANSE OPSOMMING: Die veranderinge in koolstoftoedeling na sukrose, heksoses, vesel, stysel en respirasie is in ontwikkelende internodes van suikerriet ondersoek. Die koolhidraatmetabolisme in internodes 3, 6 en 9, wat drie stadiums van toenemende rypheid verteenwoordig, is met behulp van 14Cmerkingstudies ondersoek. Dit is duidelik dat daar 'n hoë mate van koolstofsirkulering tussen die heksose- en triose-fosfaat poele voorkom. In internode 3 word tot 50% van die koolstofwat in triose-fosfate geïnkorporeer is, weer na heksosefosfaat omgeskakel. Selfs in volwasse weefsel vind daar nog soveel as 30% koolstofsirkukering plaas tussen die twee poele plaas. Koolstoftoedeling vanaf glukose na sukrose het van 34% in internode 3, tot 61% in internodes 6 en 9 toegeneem. Proteïn en selwandkomponente was die belangrikste swelgpunte vir koolstof in onvolwasse weefsel gewees. Namate die weefsel meer volwasse word, word sukrose 'n belangriker swelgpunt. Die koolstoftoedeling aan sukrose is veral ten koste van toedeling aan die selwandkomponente. Die bevinding dat die proteïenpoel 'n sterk swelgpunt is dui aan dat vorige studies die belang van respiratoriese koolstofvloei onderskat het. In teenstelling met vorige aansprake is dit duidelik dat selfs in volwasse weefsel respirasie die grootste swelpunt vir die inkomende organiese koolstof in die internode vorm. Koolstoftoedeling aan respirasie het nie noemenswaardig tussen internodes 3 en 6 verskil nie, maar het met 50% in volwasse weefsel afgeneem. Stysel is deurgaans 'n swak swelgpunt vir koolstof met die hoogste toedeling aan die poel (2%) in die jong weefsel (internode 3) . Na toediening van [U- 14C]-glukose is radioaktief gemerkte maltose gevind in suikerriet wat vroeg in die lente geoes is. Dit dui aan dat gelyktydige afbraak en sintese van stysel plaasgevind het. Die herverdeling van C-l en C-6 in glukose afkomstig van stysel is na toediening van [1_14C]_ en [6-14C]-glukose ontleed. Die ewekansige verspreiding van radioaktiwiteit tussen koolstof 1 en 6 van die glukose in stysel dui aan dat dit hoofsaaklik die triose-fosfaat translokeerder is wat in die plastied verantwoordelik is. Hierdie studie het ook aangetoon dat radioaktiewe merking van weefselsnitte 'n geskikte eksperimentele sisteem is om koolstoftoedeling in suikerriet te ondersoek. Die patroon van 14C02 vrystelling dui daarop dat die weefsel na 'n 3 h inkuberingsperiode isotopiese ewewig tussen die eksterne en interne glukose poele en die respiratoriese prosesse begin bereik het.
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4

Hendre, R. R. "Molecular basis of differentiation in plant tissue culture with special reference to sugarcane." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 1988. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3309.

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5

Jaggar, Sian Isobel. "Studies of inflammatory hyperalgesia with special reference to the viscera." Thesis, Imperial College London, 2000. http://hdl.handle.net/10044/1/7989.

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6

Heuch, J. H. R. "The tissue culture and biology of bamboos with special reference to Dendrocalamus hamiltonii Munro." Thesis, University of Aberdeen, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305447.

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Bamboos are plants of economic importance that have flower rarely. The inability to obtain flowering material on a routine basis has hindered the scientific investigation of bamboo. Paucity of flowering and the resulting lack of seed has led to extreme difficulty in taxonomic work and large-scale propagation respectively. Tissue culture appears to offer potential methods to overcome the shortage of propagules. The micropropagation potential of bamboo seedling material was investigated. Both callus methods and <i>in vitro</i> cuttings of <i>Dendrocalamus hamiltonii</i> Munro were used. Although many explants produced callus, only one type of callus, derived from excised immature embryos, regularly regenerated shoots or plantlets. Only 6% of embryos cultured produced this callus type. The callus with shoot regeneration potential was phenotypically similar to that described in the literature as embryogenic, being both white and compact. Nodal cuttings from seedlings were also cultured <i>in vitro</i>. The potential rate of multiplication was not high. Most healthy cuttings produced only one shoot. Flowers emerged from about 10% of cultures on medium containing BAP, and this result was repeated. The quality of bamboo seed available for experimentation was low. Problems of infection were encountered when initiating cultures. A number of trials were undertaken to overcome these, but some level of infection had to be tolerated. In order to assess the full potential of bamboo tissue culture a critical literature was undertaken. Many experiments reported on appeared to have used poor designs, or reported results were either unclear or conclusions were difficult to justify based on the results. Above all else, there was little confidence that results were repeatable.
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7

Wu, Qinyang. "Galanin and leu-enkephalin in the rat with special reference to adjuvant arthritis /." Stockholm, 2004. http://diss.kib.ki.se/2004/91-7349-977-3/.

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8

Rosdahl, Hans. "Microdialysis sampling from skeletal muscle and adipose tissue with special reference to the effects of insulin on tissue blood flow and glucose metabolism /." Stockholm, 1998. http://diss.kib.ki.se/1998/91-628-3050-3.

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9

Longmore, J. "Investigation of the pharmacology of autonomically innervated human tissue in situ with special reference to the effects of some novel antidepressant drugs." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377654.

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10

Kureshi, A. K. "Identifying the origins of collagen connective tissue growth and expansion with reference to inguinal herniation." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/19713/.

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The aim of this project was to understand the key mechanisms which control and initiate the process(es) by which collagen connective tissues extend, remodel and grow under the influence of external tensile loads. Inguinal herniation was used as a model of natural cell mediated bio-creep to investigate the mechanisms behind such a process since the transversalis fascia (TF); a thin collagen connective tissue undergoes dramatic extension during herniation. It was hypothesized that the TF expands due to a process of growth and remodelling rather than stretch or injury and repair. The relationship between functional tissue mechanical properties, cell responses to mechanical forces and the architecture of the ECM were investigated. TEM imaging of TF collagen fibril ultrastructure demonstrated no differences between normal and hernia specimens and therefore no evidence of microdamage/ repair. An important finding was that hernia TF was not mechanically weaker or thinner than normal TF tissue, indicating it retains its normal material properties and thickness despite dramatic extension during herniation. In addition, the TF was identified to have anisotropic mechanical properties with greater strength and stiffness in the transverse anatomical plane, a finding which has not previously been reported for the TF. The ability of normal and hernia TF fibroblasts to contract and remodel a collagen matrix were almost identical, suggesting that hernia cells retain ‘normal’ cell behaviour in terms of their cytoskeletal and cell-motor functions. Analysis of TF fibroblast creep responses using an in vitro 3D bio-creep model demonstrated, to our knowledge, the first direct functional (mechanical) defect in hernia cell behaviour, since hernia cells did not demonstrate any capacity to mediate any measurable bio-creep. Our investigations of TF mechanics, structure and cellular behaviour suggest that TF expansion in inguinal herniation occurs due to growth/remodelling rather than stretch or micro-rupture and repair but the exact mechanisms remain inconclusive until further studies are carried out.
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11

Pafundi, Deanna Hasenauer. "Image-based skeletal tissue and electron dosimetry models for the ICRP reference pediatric age series." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0024751.

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12

Goodrick, Steven James. "Adipose tissue derived cytokine like molecules (leptin, IL 6 and TNF α) : their regulation and interaction with reference to their soluble receptors." Thesis, University College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249694.

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13

Voog, Ülle. "Temporomandibular joint involvement by systemic inflammatory disease with reference to pain modulation and joint tissue destruction/." Stockholm, 2003. http://diss.kib.ki.se/2003/91-7349-709-6/.

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14

Lawence, Victor. "Studies of adipose tissue in humans with special reference to innervation by the sympathetic nervous system." Thesis, Queen Mary, University of London, 2009. http://qmro.qmul.ac.uk/xmlui/handle/123456789/562.

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This thesis reports the effects in vivo of the sympathetic nervous system (SNS) in human subcutaneous abdominal white adipose tissue (WAT) and other tissues involved in energy storage and utilisation. Cannulation of superficial veins draining skin, abdominal subcutaneous WAT and deep forearm muscle combined with isotope turnover methodology and tissue blood flow estimation was used to investigate the behaviour of these tissues under varying experimental conditions. Glucose infusion study: This examined differential substrate uptake and utilisation in the three tissues. WAT was responsible for only a small amount of glucose disposal and deep forearm muscle took up but did not release NEFA. Skin was a net exporter of lactate. Results confirm the relative purity of the venous effluent from these tissues. Sympathetic Nervous System study: This examined whole body, WAT and forearm muscle SNS activity in lean and obese individuals under fasting and postprandial conditions. Whereas whole body SNS activity was increased in the obese, regional heterogeneity of SNS activity was evidenced by reduced SNS activity in WAT. Adipose tissue blood flow was significantly reduced in the obese. This may underlie abnormal lipolysis and/or blood flow regulation in obesity. 7 Pulsatility Studies: These studies examined whether lipolysis and leptin production in human WAT is uniform or pulsatile. Novel control datasets were used to test the robustness of a widely used pulse detection algorithm. Whereas NEFA release appeared truly pulsatile, apparent leptin ‘pulses’ occurred with similar frequency in the control datasets and appear likely simply to reflect variability. Anatomical studies: Confocal immuno-fluorescence microscopy was used to demonstrate innervation of WAT in man for the first time. Such innervation appears confined to the microvasculature and suggests that the defective SNS activity within WAT is likely to affect adipose tissue biology primarily through defective regulation of adipose tissue blood flow.
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15

Zuppante, Francesca. "Qualitative analysis of a microtomographic apparatus and measurement of the bone tissue density with reference to microgravity conditions." Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3423047.

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Computed Thomography is a relatively new field in the area of non destructive imaging.It allows to reconstruct the internal structure of opaque objects without destroy them. This is a great advantage compared to conventional microscopy techniques, any optical or electronic microscope, in fact, provides information on the internal structure of samples only if samples are properly processed and sectioned. Information about three-dimensional structure could be obtained by the image of a surface or a combination of several thin slices, but in both cases information cannot be certain since methods of cutting and preparation can dramatically change the structure of the sample. Microcomputed tomography, commonly referred to as µCT, like conventional computed tomography is based on the collection of projections of X rays through a specimen and the application of tomographic principles to reconstruct the 3-D structure of the specimen. Itis based on the interaction of X-rays with matter. The attenuation ofX-rays, passingthrough an object, is dependent on thedensity and atomic number of the object under investigation. This radiation is converted in a radiographic image of the object. Images obtained from different angles are analyzed by analgorithm called Filter back projection in order to reconstruct a virtual slice through the object. When different consecutive slices are reconstructed, a 3D visualizationcan be obtained. The term "micro" denotes a scanning system much higher in resolution than conventional clinical scanners. Clinical tomographic scanners may have resolutions on the order of a millimeter or less. However, high-resolution µCT scanners may have resolutions below five microns. The high resolution of this system makes it useful in the analysis of small objects such as trabecular bone samples. Trabecularbone consists of a complicated three-dimensional network of plates and rods, arranged ina lattice-like network.The architectural parameters of trabecular bone could be strongly influenced by aging or bone diseases such as osteoarthritis or osteoporosis. Until recently, information about thesestructural parameters of trabecular bone were only available by histomorphometry, adestructive procedure limited to two-dimensional analysis. Nowadays Micro-CT, because of its capability to allow three-dimensional and non destructive analysis, found largeapplications in pre-clinical bone research.The increasing incidence and prevalence of bone pathologies on the population, increases the interest of improve an accurate bone characterization by Micro-CT. Micro-CT system, object of this study is the Skyscan 1072, located at the Technology and Health Department of the Italian National Institute of Health.One of the goal of this research is set at optimizing the system for the analysis of bone samples. The first part is dedicated on determining the resolution of the system. The performance of an imaging system is usually described by the measurement of its Modulation Transfer Function or MTF whichgives a description of how much contrast at a specific spatial frequency is maintained by the imaging process.The second part of this study is focused on the process of images reconstruction, fundamental in a Micro-CT analysis. Micro-CT images are affected by several artifacts which will be widely discussed in the following chapters. One of the most difficult artifact is beam hardening. It depends on the polychromatic X-ray tube used in these systems. The X-rays beam investing the sample is composed of X-rays with a spectrum of different energies. The attenuation of an X-ray depends on its energy, the lowestX-ray energies are preferentially absorbed. Assuming that the grey level of CT images corresponds to the linear coefficientof attenuation, which is constants depending on the material, because of the beam hardening, the attenuationof a given material is not strictly proportional to its thickness. This implies visual distortions on the images and the consequent origin of quantitative problems. In order to better understand the effect of beam hardening on Micro-CT images, the filtered back projection algorithm will be implemented in LabVIEW (Version 8.2). The Skyscan 1072 allows to correct the effect of beam hardening during the process of images reconstruction by the definition of a proper parameter. In order to define the correct value of this parameter for a bone sample analysis, a comparison between the results of both the algorithm implemented and the Skyscan reconstruction software will be evaluated. After the optimization of the system for bone analysis, nineteen trabecular bone samples, extracted from femoral heads of eight patients subject to a hip arthroplasty surgery, will be analyzed. The main problem of bone analysis by micro-CT is the processing of the reconstructed cross-sections images for the sample morphometric analysis. The post-processing of the images for the morphometric characterization usually requires a process named binarization of the images which consists on the definition of a threshold value of grey-level, necessary to distinguish bone from background. The choice of this value is a crucial task since a standard method doesn’t exist. Moreover, the inhomogeneity of bone causes another problem during the binarization process. Binarization associates each pixel of the image to bone or air, not considering that each pixel can be composed by both of them. This effect is called Partial Volume Effect and it affects especially pixels at the edges of the analyzed sample. In order to avoidproblems related to the binarization, the main goal of this study is the evaluation of a new method for the histomorphometric analysis of bone sample from the direct processing of the greylevel histogram of the images. Finally, the last part of this research will be dedicated on the remodeling process of bone. The remodeling of bone is an important research topic because of its importance in the study of bone pathologies such as osteoporosis. Osteoporosis is a bone disorder characterized by an inadequate amount and faulty structure of bone, resulting in fractures from relatively minor trauma. It leads to a bone mineral density (BMD) reduction, a bone microarchitecture deterioration and an alteration of the amount and variety of proteins in bone. Aging is the main factor of osteoporosis incidence but in the last years, another factor related to long-duration spaceflight, has been considered. Because of the difficult in reproducing in-vivo space conditions, the development of numerical models is a good alternative for the remodeling process study.<br>La Tomografia Computerizzata è una nuova tecnica di imaging che consente la ricostruzione e l'analisi della struttura interna di oggetti opachi senza che questi vengano in alcun modo danneggiati. La possibilità di analizzare campioni senza modificarli o danneggiarli conferisce a questa nuova tecnica un grande vantaggio rispetto alle tecniche di microscopia tradizionale. I microscopi ottici ed elettronici infatti, consentono di ottenere informazioni tridimensionali sulla struttura interna dei campioni analizzati ma l'opportuna preparazione dei campioni richiesta può modificarne drammaticamente la struttura interna. La Micro Tomografia Computerizzata ha lo stesso principio di funzionamento della tradizionale Tomografia Computerizzata, una corretta analisi delle proiezioni del fascio di raggi X ottenute dall'attraversamento del campione e l'applicazione dei principi base di tomografia consentono di ottenere la struttura tridimensionale del'oggetto in esame. Attraversando la materia, il fascio di raggi X subisce un'attenuazione proporzionale alla densità e al numero atomico del materiale attraversato. La radiazione attenuata è convertita in livelli di grigio nelle corrispondenti immagini radiografiche generate. Il campione viene investito dal fascio di raggi X secondo diverse angolazioni in modo tale che il successivo processamento delle proiezioni con opportuni algoritmi permetta la corretta ricostruzione della struttura tridimensionale dell'oggetto. Il termine "micro" sta ad indicare l'elevata risoluzione del sistema microtomografico. Mentre la Tomografia tradizionale permette di raggiungere risoluzioni massime dell'ordine del millimetro, la microtomografia consente di raggiungere risoluzioni molto minori, dell'ordine dei micron. Questa caratteristica rende la microtomografia adatta all'analisi di oggetti di piccole dimensioni, quali ad esempio campioni di osso trabecolare in cui le dimensioni medie delle trabecole sono paragonabili alla risoluzione del sistema.L'elevata incidenza sulla popolazione mondiale di patologie ossee, come ad esempio l'osteoartrite o l'osteoporosi, hanno spinto molti ricercatori ad approfondire la possibilità di ottenere un'accurata caratterizzazione ossea tramite l'utilizzo della microtomografia. Il microtomografo utilizzato in questa ricerca è lo Skyscan 1072, presente presso il Dipartimento di Tecnologia e Salute dell'Istituto Superiore di Sanità. Il primo obiettivo di questa ricerca sarà uno studio approndito del microtomografo a disposizione al fine di ottimizzarne l'utilizzo per l'analisi di campioni ossei. Come prima analisi si misurerà la risoluzione dello Skyscan 1072. La valutazione delle performance di sistemi per acquisizioni di immagini può essere valutata con il calcolo della Funzione di Trasferimento della Modulazione (MTF) dello strumento. La MTF descrive in modo completo la perdita di informazione nel processo che va dall'acquisizione alla visualizzazione dell'immagine al diminuire delle dimensioni dell'oggetto indagato. Essa definisce la relazione tra la risoluzione di contrasto e la risoluzione spaziale del sistema. La seconda parte di questo studio preliminare sarà focalizzata sul processo di ricostruzione delle immagini. La ricostruzione delle immagini è uno step fondamentale nell'analisi microtomografica. E' noto che le immagini provenienti da questo tipo di analisi sono affette da artefatti di diversa origine. Uno degli artefatti più dannosi e anche più difficile da rimuovere è il beam hardening. Il fascio di radiazione X che investe il campione è solitamente un fascio policromatico ovvero composto da raggi X di diversa energia. Nell'attraversare l'oggetto, i raggi con energia maggiore sono meno attenuati rispetto ai raggi di minore energia e quindi viene rilevato un valore dell’attenuazione tanto minore quanto maggiore è lo spessore del materiale attraversato. La presenza del beam hardening causa distorsioni nelle immagini create econseguenti errori nell'analisi quantitativa delle stesse. Al fine di capire l'effetto di questo artefatto sulle immagini e correggerlo al meglio per l'analisi di campioni ossei, l'algoritmo di retroproiezione filtrata, comunemente utilizzato per la ricostruzione di immagini tomografiche, verrà implementato in LabVIEW (Version 8.2). Uno dei principali problemi dell'analisi microtomografica di campioni ossei è il post-processing delle immagini per la valutazione dei parametri istomorfometrici. I programmi generalmente utilizzati richiedono una previa binarizzazione delle immagini. La binarizzazione richiede la definizione di un valore di soglia dei livelli di grigi al fine di evidenziare gli oggetti ossei nell'immagine. La scelta di questo valore è un argomento di ricerca tutt'ora aperto e non esiste un metodo standard per la sua definizione. Il processo di binarizzazione introduce un ulteriore problema relativo alla definizione dei bordi degli oggetti nell'immagine. Binarizzare significa associare ogni pixel a osso o non-osso, non considerando che alcuni pixel, specialmente quelli relativi al bordo di un oggetto, non sono facilmente associabili a una delle due classi. Al fine di eliminare il problema della binarizzazione sopra esposto, l'obiettivo principale di questa ricerca sarà lo sviluppo di un nuovo metodo per l'analisi istomorfometrica delle ossa, basato sull'analisi diretta dell'istogramma dei livelli di grigi dell'immagine. L'ultima parte della ricerca sarà dedicata al processo di rimodellamento delle ossa. Capire come l'osso reagisce ai carichi esterni è molto importante in quanto consente di avere maggiori informazioni nello studio delle patologie ossee, quali ad esempio l' osteoporosi. L'osteoporosi è una patologia ossea caratterizzata da una perdita di massa ossea e resistenza causata da fattori nutrizionali, metabolici o patologici. Lo scheletro è soggetto ad un maggiore rischio di fratture patologiche, in seguito alla diminuzione di densità ossea e alle modificazioni della microarchitettura delle ossa. L'invecchiamento, nonostante sia il principale fattore di incidenza di questa patologia, non è l'unico. Negli ultimi anni, si è posta particolare attenzione all'elevata percentuale di insorgenza di questa malattia in soggetti che hanno partecipato a missioni spaziali di lunga durata. In condizioni di microgravità, il tessuto osseo, non essendo sollecitato da carichi esterni, va incontro ad aumento del catabolismo e perde l'1- 2% del calcio totale dopo solo qualche settimana di microgravità. Non è semplice riprodurre queste condizioni in esperimenti in-vivo, una possibile alternativa è lo sviluppo di modelli numerici per la simulazione del processo di rimodellamento osseo.
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16

Heikkilä, V. P. (Vesa-Pekka). "New techniques and methods for decreasing healthy tissue dose in prostate cancer radiotherapy, with special reference to rectal doses." Doctoral thesis, Oulun yliopisto, 2016. http://urn.fi/urn:isbn:9789526212081.

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Abstract Prostate cancer is the most common cancer among men in Western industrialized countries. Approximately 60% of prostate cancer patients receive radiotherapy at some phase of the disease, a treatment based on the use of ionizing radiation to kill or control malignant cells. Unfortunately, adjoining healthy tissues are also affected by exposure to ionization, potentially leading to the emergence of adverse side effects, even several years later. The main radiation treatment modalities are external radiotherapy and low dose rate (LDR) or high dose rate (HDR) brachytherapy. Different techniques and methods are used to decrease the dose to healthy tissues, thus limiting the possibility of adverse effects. In this thesis a novel technique and associated equipment were developed whereby brachytherapy can be performed by inserting all needles simultaneously. This reduces the implantation time, thus minimizing the impairing effect on seed positioning accuracy resulting from prostate swelling. A phantom model was also constructed for testing and training purposes. DuraSeal® was investigated as a spacer material between the prostate and rectum, and its effect on rectal dose was evaluated during brachytherapy and external radiotherapy. DuraSeal® is resorbed over one to six months, thus altering rectal doses compared with the original dose plan. In brachytherapy, the resorption effect on rectal doses was calculated along with an evaluation of the potential of using different isotopes. In external radiotherapy, the resorption effect on rectal dose-volume histograms (DVHs) was calculated and the need for adaptive planning considered. DuraSeal®, as a spacer gel, clearly has favorable effects on rectal and anterior rectal wall DVHs in brachytherapy and external radiotherapy, and has the potential to decrease adverse effects. It is especially beneficial in hypofractionated treatments and external radiotherapy and brachytherapy combination treatment. In LDR brachytherapy using permanent seeds, dose planning is recommended prior to gel injection to prevent excessive rectal tolerance doses in situations where gel is rapidly resorbed. In external radiotherapy, the use of adaptive planning with a spacer gel improves rectal DVH, but is not necessary according to this thesis<br>Tiivistelmä Eturauhasen syöpä on läntisten teollistuneiden maiden miesten yleisin syöpä. Arviolta 60 % eturauhassyöpäpotilaista saa sairauden jossain vaiheessa sädehoitoa. Sädehoito perustuu syöpäsolujen kontrolloimiseen ja tuhoamiseen ionisoivalla säteilyllä. Valitettavasti ionisoiva säteily vaikuttaa myös ympäröivään tervekudokseen aiheuttaen mahdollisia haittavaikutuksia jopa vuosien päästä. Sädehoidon kolme päätyyppiä ovat ulkoinen sädehoito sekä matala- ja korkea-annosnopeuksinen tykösädehoito (brakyterapia). Tervekudosannosten pienentämiseksi ja siten myös mahdollisten haittavaikutusten vähentämiseksi käytetään eri menetelmiä ja tekniikoita. Tässä väitöskirjassa kehitettiin uusi menetelmä ja laitteisto, joiden avulla voidaan brakyterapiassa asettaa kaikki neulat samanaikaisesti eturauhaseen. Menetelmä nopeuttaa implantointivaihetta, jolloin eturauhasen turpoaminen ei ehdi vaikuttaa jyvien asettelutarkkuutta heikentävästi. Samassa yhteydessä rakennettiin myös fantomi laadunvalvontaa ja harjoittelua varten. Työssä tutkittiin ja arvioitiin myös DuraSeal® geelin käyttöä välikemateriaalina eturauhasen ja peräsuolen välissä sekä geelin vaikutusta peräsuoliannoksiin. DuraSeal® resorboituu kuuden kuukauden aikana muuttaen alkuperäisen annossuunnitelman mukaista peräsuoliannosta. Brakyterapiassa tutkittiin ja laskettiin resorption vaikutusta sekä arvioitiin eri isotooppien käyttöä. Ulkoisessa sädehoidossa laskettiin resorption vaikutusta peräsuolen tilavuushistogrammeihin ja tutkittiin mahdollisen adaptiivisen suunnittelun käyttöä. DuraSeal® geelin käyttö välikemateriaalina pienentää selkeästi peräsuoliannoksia ja siten myös mahdollisesti tervekudosten haittavaikutuksia sekä ulkoisessa sädehoidossa että brakyterapiassa. Geelin käyttö on erityisen hyödyllistä hypofraktiohoidoissa sekä ulkoisen sädehoidon ja brakyterapian kombinoidussa käytössä. Matala-annosnopeuksisessa brakyterapiassa (jyvähoidoissa) annossuunnitelma suositellaan tehtäväksi ennen geelin ruiskutusta, jotta peräsuolen toleranssiannoksia ei ylitettäisi vaikka geeli resorboituisikin nopeasti. Ulkoisessa sädehoidossa adaptiivinen suunnittelu välikegeelin kanssa tuo lisäarvoa pienentämällä edelleen peräsuoliannoksia, mutta ei ole välttämätöntä
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17

Walker, Mariah Louise. "An analysis of antiarrhythmic action in a series of related compounds with reference to their selectivity for ischaemic tissue." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ61193.pdf.

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18

Qu, Yangyang [Verfasser]. "Age- and gender-related reference values of biventricular strains measured by cardiovascular magnetic resonance based tissue tracking / Yangyang Qu." Ulm : Universität Ulm, 2021. http://d-nb.info/124118903X/34.

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19

Schulze, Felix, Deeksha Malhan, Khassawna Thaqif El, et al. "A tissue-based approach to selection of reference genes for quantitative real-time PCR in a sheep osteoporosis model." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-232280.

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BACKGROUND: In order to better understand the multifactorial nature of osteoporosis, animal models are utilized and compared to healthy controls. Female sheep are well established as a model for osteoporosis induced by ovariectomy, calcium and vitamin D low diet, application of steroids, or a combination of these treatments. Transcriptional studies can be performed by applying quantitative real time PCR (RT-qPCR). RT-qPCR estimates mRNA-levels of target genes in relation to reference genes. A chosen set of reference genes should not show variation under experimental conditions. Currently, no standard reference genes are accepted for all tissue types and experimental conditions. Studies examining reference genes for sheep are rare and only one study described stable reference in mandibular bone. However, this type of bone differs from trabecular bone where most osteoporotic fractures occur. The present study aimed at identifying a set of reference genes for relative quantification of transcriptional activity of ovine spine bone and ovine in vitro differentiated mesenchymal stromal cells (MSC) for reliable comparability. METHODS: Twelve candidate reference genes belonging to different functional classes were selected and their expression was measured from cultured ovMSCs (n = 18) and ovine bone samples (n = 16), respectively. RefFinder was used to rank the candidate genes. RESULTS: We identified B2M, GAPDH, RPL19 and YWHAZ as the best combination of reference genes for normalization of RT-qPCR results for transcriptional analyses of these ovine samples. CONCLUSION: This study demonstrates the importance of applying a set of reference genes for RT-qPCR analysis in sheep. Based on our data we recommend using four identified reference genes for relative quantification of gene expression studies in ovine bone or for in vitro experiments with osteogenically differentiated ovine MSCs.
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20

Schulze, Felix, Deeksha Malhan, Khassawna Thaqif El, et al. "A tissue-based approach to selection of reference genes for quantitative real-time PCR in a sheep osteoporosis model." BioMed Central, 2017. https://tud.qucosa.de/id/qucosa%3A30735.

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BACKGROUND: In order to better understand the multifactorial nature of osteoporosis, animal models are utilized and compared to healthy controls. Female sheep are well established as a model for osteoporosis induced by ovariectomy, calcium and vitamin D low diet, application of steroids, or a combination of these treatments. Transcriptional studies can be performed by applying quantitative real time PCR (RT-qPCR). RT-qPCR estimates mRNA-levels of target genes in relation to reference genes. A chosen set of reference genes should not show variation under experimental conditions. Currently, no standard reference genes are accepted for all tissue types and experimental conditions. Studies examining reference genes for sheep are rare and only one study described stable reference in mandibular bone. However, this type of bone differs from trabecular bone where most osteoporotic fractures occur. The present study aimed at identifying a set of reference genes for relative quantification of transcriptional activity of ovine spine bone and ovine in vitro differentiated mesenchymal stromal cells (MSC) for reliable comparability. METHODS: Twelve candidate reference genes belonging to different functional classes were selected and their expression was measured from cultured ovMSCs (n = 18) and ovine bone samples (n = 16), respectively. RefFinder was used to rank the candidate genes. RESULTS: We identified B2M, GAPDH, RPL19 and YWHAZ as the best combination of reference genes for normalization of RT-qPCR results for transcriptional analyses of these ovine samples. CONCLUSION: This study demonstrates the importance of applying a set of reference genes for RT-qPCR analysis in sheep. Based on our data we recommend using four identified reference genes for relative quantification of gene expression studies in ovine bone or for in vitro experiments with osteogenically differentiated ovine MSCs.
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21

Al-Hassi, Hafid Omar Saad. "Tissue distribution of selected vasoactive peptides with special reference to their actions on ciliary activity of the human Fallopian tube." Thesis, University of Sheffield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301589.

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22

Athanassopoulou, F. "A study of myxosporea SPP in Rutilus L. (roach) with particular reference to Myxidium rhodei Leger, 1905 in the renal tissue." Thesis, University of Stirling, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277409.

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23

Hallberg, Gunilla. "Effects of Endogenous and Exogenous Hormones on the Female Breast : With Special Reference to the Expression of Proteoglycans." Doctoral thesis, Uppsala universitet, Institutionen för kvinnors och barns hälsa, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-147793.

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This thesis aims to study the effects of endogenous and exogenous hormones and mammographic breast density (BD) on cellular markers in non-cancerous female breast tissue. Women on the waiting list for breast reduction plastic surgery were recruited (n = 79), and randomized to 2 months of hormone therapy or no therapy before surgery. The women had a mammogram and a needle biopsy 2 months before surgery and tissue samples were obtained at the operation. In premenopausal women, estrogen receptor (ER)α levels were associated with age (p = 0.0002), were similar in the follicular and luteal phases of the menstrual cycle and were higher in parous than in nulliparous women (p = 0.009). Current smokers had lower PR levels than non-smokers (p = 0.019). Women on oral contraception had lower ERα (p = 0.048) and PR (p = 0.007) levels than women in the follicular phase. The ERα levels did not differ significantly between postmenopausal estrogen and estrogen-progestogen users, but PR levels were lower among estrogen-progestogen users (p = 0.03). We found lower expression of the genes for decorin and syndecans 1 and 4 in the luteal phase than in the follicular phase, among parous women. Protein levels of the androgen receptor, syndecan-4 and decorin was lower in premenopausal women who were using oral contraceptives (OC) than in those in the follicular phase (p = 0.002 - 0.02), whereas no significant differences between OC use and the luteal phase were found. In premenopausal women, BD was negatively associated with age and body mass index but was similar for the menstrual phases. Breast density was associated with genetic expression of the androgen receptor and remained significant after adjustment for age (rs = 0.56; p = 0.04). After adjustement for age, breast density was also marginally associated with expression of the caspase 3 gene (0.55; 0.053). However, protein levels of caspase 3 was negatively associated (-0.61; 0.03).
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24

Kawamoto, Mayumi Silva. "Produção de Materiais de Referência Para Nutrientes e Contaminantes Inorgânicos em Amostras de Ração e Tecido de Peixe." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-14032019-102135/.

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Para que o crescimento da produção pesqueira no Brasil aconteça de maneira sustentável é necessário o desenvolvimento de bases científicas e tecnológicas sólidas, que solucionem as demandas existentes nos diversos elos da cadeia produtiva. Uma das principais evidências da qualidade dos produtos é fornecida pelos resultados analíticos, cuja confiabilidade e exatidão podem ser asseguradas pelo emprego de materiais de referência (RM). Neste contexto, foi desenvolvido material de referência de ração para peixe para macro e micronutrientes e parâmetros bromatológicos e está em fase final de desenvolvimento um RM de tecido de peixe para nutrientes e contaminantes inorgânicos. A produção dos materiais seguiu as diretrizes das ISO Guias 30-35, considerando a preparação, envase, irradiação, massa mínima, homogeneidade, estabilidade a curto e a longo prazo e caracterização do material. Para produzir os RMs de ração e tecido de peixe, as amostras foram obtidas a partir de fornecedores comerciais. Os materiais foram secos/liofilizados, moídos, homogeneizados e envasados em frascos de vidro âmbar que, posteriormente, foram submetidos à irradiação com raios gama, para esterilização do material, visando o aumento do seu tempo de prateleira. A caracterização química do RM de ração foi efetuada através de um ensaio colaborativo, com a participação de laboratórios de diferentes instituições, públicas e privadas. A avaliação da estimativa da massa mínima, da homogeneidade e da estabilidade do material foi realizada utilizando-se como técnicas de determinação a espectrometria de emissão óptica com plasma acoplado indutivamente (ICP OES) e a espectrometria de massa por plasma acoplado indutivamente (ICP-MS). Foi possível observar que o lote de ração para peixe pode ser considerado homogêneo para Ca, Cu, Fe, Mg, Mn, Na e S, uma vez que não foi verificada diferença significativa no intervalo de confiança de 95%. A avaliação da estabilidade a longo prazo do RM de ração foi feita pela análise de resíduos da regressão em conjunto com a ANOVA e a avaliação da estabilidade a curto prazo foi obtida por meio de regressão linear simples. O RM de ração foi considerado suficientemente estável para ser armazenado à temperatura ambiente. Os resultados obtidos durante a produção do RM de ração e através do ensaio colaborativo possibilitaram a caracterização química e o cálculo das componentes de incerteza, sendo elaborado o documento com os valores de referência RM e as incertezas expandidas para cada um dos analitos avaliados. O RM de tecido de peixe foi avaliado em sua homogeneidade e estabilidade a curto prazo, sendo considerado homogêneo e estável para transporte a temperaturas inferiores a 37ºC.<br>For the growth of fisheries production in a sustainable way is necessary the development of sound scientific and technological basis, addressing the existing demands in the various links in the production chain. One of the main evidences of the quality of the products is provided by the analytical results, whose reliability and accuracy can be assured by the use of reference materials (RM). In this context, it was produced a RM of fish feed for macro-and micronutrients and proximates and it is in its final stage of development a RM of fish tissue for nutrients and inorganic contaminants. The production of reference materials followed the ISO Guides 30-35 norms: preparation and packaging, irradiation, minimum sample, homogeneity, short- and long-term stability, and material characterization. In order to produce a RMs of fish feed and fish tissue, the matrices were obtained from commercial suppliers. The samples were dried/freeze-dried, pulverized, homogenized and aliquoted into amber glass bottles, which later were subjected to gamma Ray irradiation (5-10 KGy), in order to increase its shelf life. The chemical characterization of the candidate fish feed RM was made through a collaborative trial with the participation of various laboratories of different institutions. The study of minimum sample, homogeneity and stability of the material were performed using inductively coupled plasma optical emission spectrometry (ICP OES) and inductively coupled plasma mass spectrometry (ICP-MS) as determination techniques. The fish feed batch can be considered homogeneous for Ca, Cu, Fe, Mg, Mn and Na, since there was no significant difference in significance level of 0.05. Long-term stability study of the RM of fish feed was performed by the residual analysis in regression and ANOVA and the short-term stability study was performed by simple linear regression. The RM was considered sufficiently stable to be stored at room temperature. The data obtained along the production and through the collaborative trial allowed the characterization of the fish feed RM and the determination of uncertainties components. It was prepared the analysis document with the reference values and expanded uncertainties. The RM of fish tissue was evaluated in its homogeneity and short-term stability and its considered homogeneous and stable to be transported under normal conditions.
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25

Tan, Wah Lay, Lok-tin Wong, 陳華麗, and 黃洛天. "A systematic review of post-extractional alveolar hard and soft tissue dimensional changes in humans : comparison of studies with non-fixed or fixed reference points." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B48395456.

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Background: Removal of teeth results in both horizontal and vertical changes of hard and soft tissue dimensions. The magnitude of these changes is important for decision-making and comprehensive treatment planning, with provisions for possible solutions to expected complications during prosthetic rehabilitation. Objectives: to review all English dental literature to assess the magnitude of dimensional changes of both the hard and soft tissues of the alveolar ridge up to 12 months following tooth extraction in humans. Materials and methods: An electronic MEDLINE and CENTRAL search complemented by manual searching was conducted to identify randomised controlled clinical trials and prospective cohort studies on hard and soft tissue dimensional changes after tooth extraction. Only studies reporting on undisturbed post-extraction dimensional changes relative to a fixed reference point over a clearly stated time period were included. Assessment of the identified studies and data extraction was performed independently by two reviewers. Data collected were reported by descriptive methods. Weighted means and percentages of the dimensional changes over time were calculated where appropriate. Results: The search provided 3954 titles and 238 abstracts. Full text analysis was performed for 104 articles resulting in 20 studies that met the inclusion criteria. In human hard tissue, horizontal dimensional reduction (3.79 ± 0.23 mm) was more than vertical reduction (1.24 ± 0.11 mm on buccal, 0.84 ± 0.62 mm on mesial and 0.80 ± 0.71 mm on distal sites) at 6 months. Percentage vertical dimensional change was 11-22 % at 6 months. Percentage horizontal dimensional change was 32% at 3 months, and 29-63% at 6-7 months. Soft tissue changes demonstrated 0.4-0.5 mm gain of thickness at 6 months on the buccal and lingual aspects. Horizontal dimensional changes of hard and soft tissue (loss of 0.1 mm to 6.1 mm) was more substantial than vertical change (loss 0.9 mm to gain 0.4mm) during observation periods of up to 12 months, when study casts were utilised as a means of documenting the changes. Conclusions: Human re-entry studies showed horizontal bone loss of 29-63% and vertical bone loss of 11-22% after 6 months following tooth extraction. These studies demonstrated rapid reductions in the first 3-6 months that was followed by gradual reductions in dimensions thereafter.<br>published_or_final_version<br>Dental Surgery<br>Master<br>Master of Dental Surgery
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26

Jenkins, Sharon. "Measurements of the complex permittivity of dielectric reference liquids and human tissues." Thesis, University of Bristol, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241174.

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27

Dandekar, Eshan M. "Comparative Analysis of Body Composition and Reference Values of Visceral Adipose Tissues in Various American Collegiate Sports." DigitalCommons@CalPoly, 2018. https://digitalcommons.calpoly.edu/theses/1941.

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Background: Currently, body composition (BC) assessment is usually performed to diagnose disease states and accurately estimate certain types of tissues. In athletes, performing BC assessments helps gauge training and nutrition programs to see if they are adequately meeting the athlete’s needs to improve performance. Annual Dual Energy X-ray Absorptiometry (DXA) scans before the start of an athlete’s season can help identify an athlete’s preparedness or health before training begins. Objective: To assess the preseason BC of four collegiate sports: Men’s basketball, men’s baseball, women’s volleyball, and women’s soccer, for Fat Mass (FM), bone mineral density BMD), Fat-Free Mass (FFM), and visceral adipose tissue (VAT). Methods: DXA (Lunar iDXA, GE Healthcare) scans were performed before the start of pre-season training for Men’s Basketball, Baseball, Women’s Volleyball, and Women’s Soccer. End-season DXA scans were performed after the end of the regular season for Men’s Basketball and Baseball athletes. Visceral Adipose Tissue was measured using CoreScan software provided by GE and Fat Mass Index (FMI) and Fat-Free Mass Index (FFMI) were calculated from scanned values. Results: Between the various sports, there were several significant differences that were apparent. Height and percentage of Fat Mass (%BF) were significantly different between all sports except Women’s Volleyball and Women’s Soccer. BMI, VAT, and FFMI were significantly different between males and females. Changes over a season showed increased BMD in Men’s Basketball (2.79 to 2.99 Z-score, pre to end of season scan respectively; p < 0.001). No other observations were noticed to be significant. Conclusions: Sports-specific training and sex have large influences on the body composition of athletes. FMI and FFMI are two indices that may have a stronger indication to health than parameters considered for those who are sedentary and non-active. Female athletes have little to no amounts of VAT and this warrants further investigation.
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28

Matos, Eugène de. "Definition et production de rayonnements neutroniques de reference en vue de l'etalonnage d'appareils de radioprotection." Toulouse 3, 1987. http://www.theses.fr/1987TOU30241.

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29

Rahn, Helene. "Semi-quantitative röntgentomographische Untersuchungen zur Biodistribution von magnetischen Nanopartikeln in biologischem Gewebe." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-83592.

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Im Rahmen der vorliegenden Dissertationsschrift „Semi-quantitative röntgentomographische Untersuchungen zur Biodistribution von magnetischen Nanopartikeln in biologischem Gewebe“ wurden tomographische Untersuchungen an biologischen Objekten durchgeführt. Bei diesen Objekten handelt es sich um Gewebeproben nach minimal-invasiven Krebstherapien wie zum Beispiel magnetischem Drug Targeting und magnetischer Wärmebehandlung. Der Erfolg dieser Therapien ist sowohl abhängig von der korrekten Verteilung der magnetischen Nanopartikel als auch von der Tatsache, dass diese in der Zielregion in einer ausreichenden Menge vorhanden sind. Das Vorliegen dieser beiden Voraussetzungen ist in der vorliegenden Arbeit untersucht worden. Dabei lag der Schwerpunkt der Arbeit auf der Quantifizierung von magnetischem Material in unterschiedlichen biologischen Gewebeproben mittels Röntgenmikrocomputertomographie (XµCT). Für diesen Zweck wurde ein Kalibrationssystem mit speziellen Phantomen entwickelt, mit dessen Hilfe eine Nanopartikelkonzentration einem Grauwert voxelweise zugewiesen werden kann. Mit Hilfe der Kalibration kann der Nanopartikelgehalt sowohl in monochromatischen als auch in polychromatischen tomographischen Daten im Vergleich zu magnetorelaxometrischen Ergebnissen mit wenigen Prozent Abweichung ermittelt werden. Trotz Polychromasie und damit einhergehenden Artefakten können 3-dimensionale röntgentomographische Datensätze mit einer geringfügigen Konzentrationsabweichung im Vergleich zur quantitativen Messmethode Magnetorelaxometrie semi-quantitativ ausgewertet werden<br>The success of the minimal invasive cancer therapies, called magnetic drug targeting and magnetic heating treatment, depends strongly on the correct distribution of the magnetic nanoparticles on one side. On the other side it depends on the fact that a sufficient amount of magnetic nanoparticles carrying drugs is accumulated in the target region. To study whether these two requirements are fulfilled motivates this PhD thesis „Semi-quantitative X-ray-tomography examinations of biodistribution of magnetic nanoparticles in biological tissues“. The analysis of the distribution of the magnetic nanoparticles in tumours and other tissue examples is realized by means of X-ray-micro computer tomography (XμCT). The work focuses on the quantification of the magnetic nanoparticles in different biological tissue samples by means of XµCT. A calibration of the tomographic devices with adequate phantoms, developed in the frame of this work, opens now the possibility to analyze tomographic data in a semi-quantitative manner. Thus, the nanoparticle concentration can be allocated voxel-wise to the grey values of the three-dimensional tomographic data. With the help of calibration of the tomography equipments used, polychromatic as well as monochromatic three-dimensional representations of objects can be analyzed with regard to the biodistribution of magnetic nanoparticles as well as with regard to their quantity. The semi-quantitative results have been compared with results obtained with a quantitative measurement method magnetorelaxometry (MRX). Thereby a good agreement of the semi-quantitative and quantitative data has been figured out
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30

Metairon, Sabrina. "Determinação de elementos de relevância clínica em tecidos biológicos decamundongos distróficos Dmdmdx/J por AAN." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-03042012-090522/.

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Neste trabalho a determinação de elementos químicos em tecidos biológicos (sangue total, ossos e orgãos) de camundongos distróficos, usados como modelo animal da Distrofia Mucular de Duchenne (DMD), foi realizada utilizando técnica analítica nuclear. O objetivo do presente trabalho foi a determinação dos valores de referência para elementos de relevância em bioquímica clínica (Ca, Cl, K, Mg e Na) e nutricional (Br e S) em sangue total, tíbia, quadríceps anterior e coração de camundongos da linhagem distrófica Dmdmdx/J (10 machos e 10 fêmeas) e grupo controle C57BL/6J (10 machos), utilizando a técnica de Análise por Ativação com Nêutrons AAN. Para obter mais detalhes das alterações que esta disfunção pode causar nesses tecidos biológicos, foram calculadas matrizes de correlação entre as espécies Dmdmdx/J e comparadas ao grupo controle C57BL/6J. Para a realização deste estudo 119 amostras de tecidos biológicos foram irradiadas no reator nuclear IEA-R1 no IPEN (São Paulo, Brasil). Os resultados de análise, por AAN, constituem as primeiras estimativas para os valores de referência nesses tecidos biológicos dos camundongos Dmdmdx/J e C57BL/6J. Além disso, as alterações em alguns dos coeficientes de correlações entre os animais saudáveis e com disfunção indicam uma conexão entre esses elementos no sangue, tíbia, quadríceps e coração. Esses dados poderão auxiliar pesquisadores avaliar e comparar as vantagens e desvantagens dos diferentes tratamentos, realizados na distrofia muscular, quando estes modelos animais forem empregados, auxiliando os pesquisadores a avaliar a eficácia de novos procedimentos terapêuticos antes de serem empregados em paciente com DMD.<br>In this work the determination of chemistry elements in biological tissues (whole blood, bones and organs) of dystrophic mice, used as animal model of Duchenne Muscular Dystrophy (DMD), was performed using analytical nuclear technique. The aim of this work was to determine reference values of elements of clinical (Ca, Cl, K, Mg, Na) and nutritional (Br and S) relevance in whole blood, tibia, quadriceps and hearts from Dmdmdx/J (10 males and 10 females) dystrophic mice and C57BL/6J (10 males) control group mice, using Neutron Activation Analysis technique (NAA). To show in more details the alterations that this disease may cause in these biological tissues, correlations matrixes of the DMDmdx/J mouse strain were generated and compared with C57BL/6J control group. For this study 119 samples of biological tissue were irradiated in the IEA-R1 nuclear reactor at IPEN (São Paulo, Brazil). The concentrations of these elements in biological tissues of Dmdmdx/J and C57B/6J mice are the first indicative interval for reference values. Moreover, the alteration in some correlation coefficients data among the elements in the health status and in the diseased status indicates a connection between these elements in whole blood, tibia, quadriceps and heart. These results may help the researchers to evaluate the efficiency of new treatments and to compare the advantages of different treatment approaches before performing tests in patients with muscular dystrophy.
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31

Fenollosa, Artés Felip. "Contribució a l'estudi de la impressió 3D per a la fabricació de models per facilitar l'assaig d'operacions quirúrgiques de tumors." Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/667421.

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La present tesi doctoral s’ha centrat en el repte d’aconseguir, mitjançant Fabricació Additiva (FA), models per a assaig quirúrgic, sota la premissa que els equips per fer-los haurien de ser accessibles a l’àmbit hospitalari. L’objectiu és facilitar l’extensió de l’ús dels prototips com a eina de preparació d’operacions quirúrgiques, transformant la pràctica mèdica actual de la mateixa manera que en el seu moment ho van fer tecnologies com les que van facilitar l’ús de radiografies. El motiu d’utilitzar FA, en lloc de tecnologies més tradicionals, és la seva capacitat de materialitzar de forma directa les dades digitals obtingudes de l’anatomia del pacient mitjançant sistemes d’escanejat tridimensional, fent possible l’obtenció de models personalitzats. Els resultats es centren en la generació de nou coneixement sobre com aconseguir equipaments d’impressió 3D multimaterials accessibles que permetin l’obtenció de models mimètics respecte als teixits vius. Per facilitar aquesta buscada extensió de la tecnologia, s’ha focalitzat en les tecnologies de codi obert com la Fabricació per Filament Fos (FFF) i similars basades en líquids catalitzables. La recerca s’alinea dins l’activitat de desenvolupament de la FA al CIM UPC, i en aquest àmbit concret amb la col·laboració amb l’Hospital Sant Joan de Déu de Barcelona (HSJD). El primer bloc de la tesi inclou la descripció de l’estat de l’art, detallant les tecnologies existents i la seva aplicació a l’entorn mèdic. S’han establert per primer cop unes bases de caracterització dels teixits vius -sobretot tous- per donar suport a la selecció de materials que els puguin mimetitzar en un procés de FA, a efectes de millorar l’experiència d’assaig dels cirurgians. El caràcter rígid dels materials majoritàriament usats en impressió 3D els fa poc útils per simular tumors i altres referències anatòmiques. De forma successiva, es tracten paràmetres com la densitat, la viscoelasticitat, la caracterització dels materials tous a la indústria, l’estudi del mòdul elàstic de teixits tous i vasos, la duresa d’aquests, i requeriments com l’esterilització dels models. El segon bloc comença explorant la impressió 3D mitjançant FFF. Es classifiquen les variants del procés des del punt de vista de la multimaterialitat, essencial per fer models d’assaig quirúrgic, diferenciant entre solucions multibroquet i de barreja al capçal. S’ha inclòs l’estudi de materials (filaments i líquids) que serien més útils per mimetitzar teixits tous. Es constata com en els líquids, en comparació amb els filaments, la complexitat del treball en processos de FA és més elevada, i es determinen formes d’imprimir materials molt tous. Per acabar, s’exposen sis casos reals de col·laboració amb l’HJSD, una selecció d’aquells en els que el doctorand ha intervingut en els darrers anys. L’origen es troba en la dificultat de l’abordatge d’operacions de resecció de tumors infantils com el neuroblastoma, i a la iniciativa del Dr. Lucas Krauel. Finalment, el Bloc 3 té per objecte explorar nombrosos conceptes (fins a 8), activitat completada al llarg dels darrers cinc anys amb el suport dels mitjans del CIM UPC i de l’activitat associada a treballs finals d’estudis d’estudiants de la UPC, arribant-se a materialitzar equipaments experimentals per validar-los. La recerca ampla i sistemàtica al respecte fa que s’estigui més a prop de disposar d’una solució d’impressió 3D multimaterial de sobretaula. Es determina que la millor via de progrés és la de disposar d’una pluralitat de capçals independents a fi de capacitar la impressora 3D per integrar diversos conceptes estudiats, materialitzant-se una possible solució. Cloent la tesi, es planteja com seria un equipament d’impressió 3D per a models d’assaig quirúrgic, a fi de servir de base per a futurs desenvolupaments.<br>La presente tesis doctoral se ha centrado en el reto de conseguir, mediante Fabricación Aditiva (FA), modelos para ensayo quirúrgico, bajo la premisa que los equipos para obtenerlos tendrían que ser accesibles al ámbito hospitalario. El objetivo es facilitar la extensión del uso de modelos como herramienta de preparación de operaciones quirúrgicas, transformando la práctica médica actual de la misma manera que, en su momento, lo hicieron tecnologías como las que facilitaron el uso de radiografías. El motivo de utilizar FA, en lugar de tecnologías más tradicionales, es su capacidad de materializar de forma directa los datos digitales obtenidos de la anatomía del paciente mediante sistemas de escaneado tridimensional, haciendo posible la obtención de modelos personalizados. Los resultados se centran en la generación de nuevo conocimiento para conseguir equipamientos de impresión 3D multimateriales accesibles que permitan la obtención de modelos miméticos respecto a los tejidos vivos. Para facilitar la buscada extensión de la tecnología, se ha focalizado en las tecnologías de código abierto como la Fabricación por Hilo Fundido (FFF) y similares basadas en líquidos catalizables. Esta investigación se alinea dentro de la actividad de desarrollo de la FA en el CIM UPC, y en este ámbito concreto con la colaboración con el Hospital Sant Joan de Déu de Barcelona (HSJD). El primer bloque de la tesis incluye la descripción del estado del arte, detallando las tecnologías existentes y su aplicación al entorno médico. Se han establecido por primera vez unas bases de caracterización de los tejidos vivos – principalmente blandos – para dar apoyo a la selección de materiales que los puedan mimetizar en un proceso de FA, a efectos de mejorar la experiencia de ensayo de los cirujanos. El carácter rígido de los materiales mayoritariamente usados en impresión 3D los hace poco útiles para simular tumores y otras referencias anatómicas. De forma sucesiva, se tratan parámetros como la densidad, la viscoelasticidad, la caracterización de materiales blandos en la industria, el estudio del módulo elástico de tejidos blandos y vasos, la dureza de los mismos, y requerimientos como la esterilización de los modelos. El segundo bloque empieza explorando la impresión 3D mediante FFF. Se clasifican las variantes del proceso desde el punto de vista de la multimaterialidad, esencial para hacer modelos de ensayo quirúrgico, diferenciando entre soluciones multiboquilla y de mezcla en el cabezal. Se ha incluido el estudio de materiales (filamentos y líquidos) que serían más útiles para mimetizar tejidos blandos. Se constata como en los líquidos, en comparación con los filamentos, la complejidad del trabajo en procesos de FA es más elevada, y se determinan formas de imprimir materiales muy blandos. Para acabar, se exponen seis casos reales de colaboración con el HJSD, una selección de aquellos en los que el doctorando ha intervenido en los últimos años. El origen se encuentra en la dificultad del abordaje de operaciones de resección de tumores infantiles como el neuroblastoma, y en la iniciativa del Dr. Lucas Krauel. Finalmente, el Bloque 3 desarrolla numerosos conceptos (hasta 8), actividad completada a lo largo de los últimos cinco años con el apoyo de los medios del CIM UPC y de la actividad asociada a trabajos finales de estudios de estudiantes de la UPC, llegándose a materializar equipamientos experimentales para validarlos. La investigación amplia y sistemática al respecto hace que se esté más cerca de disponer de una solución de impresión 3D multimaterial de sobremesa. Se determina que la mejor vía de progreso es la de disponer de una pluralidad de cabezales independientes, a fin de capacitar la impresora 3D para integrar diversos conceptos estudiados, materializándose una posible solución. Para cerrar la tesis, se plantea cómo sería un equipamiento de impresión 3D para modelos de ensayo quirúrgico, a fin de servir de base para futuros desarrollos.
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32

Wu, Jian Ting, and 吳建廷. "Lipid composition of tumor tissue and surrounding reference tissue in breast cancer patients." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/44993482963418610331.

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Shall, Sydney. "The relation between the tissue and blood plasma proteins, with special reference to the perineal tissue of the baboon (Papo ursinus)." Thesis, 2014.

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Bagulho, Inês Correia. "Reference tissue normalization of prostate MRI with automatic multi-organ deep learning pelvis segmentation." Master's thesis, 2018. http://hdl.handle.net/10451/36792.

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Tese de mestrado integrado, Engenharia Biomédica e Biofísica (Engenharia Clínica e Instrumentação Médica) Universidade de Lisboa, Faculdade de Ciências, 2018<br>Prostate cancer is the most common cancer among male patients and second leading cause of death from cancer in men (excluding non-melanoma skin cancer). Magnetic Resonance Imaging (MRI) is currently becoming the modality of choice for clinical staging of localized prostate cancer. However, MRI lacks intensity quantification which hinders its diagnostic ability. The overall aim of this dissertation is to automate a novel normalization method that can potentially quantify general MR intensities, thus improving the diagnostic ability of MRI. Two Prostate multi-parametric MRI cohorts, of 2012 and 2016, were used in this retrospective study. To improve the diagnostic ability of T2-Weighted MRI, a novel multi-reference tissue normalization method was tested and automated. This method consists of computing the average intensity of the reference tissues and the corresponding normalized reference values to define a look-up-table through interpolation. Since the method requires delineation of multiple reference tissues, an MRI-specific Deep Learning model, Aniso-3DUNET, was trained on manual segmentations and tested to automate this segmentation step. The output of the Deep Learning model, that consisted of automatic segmentations, was validated and used in an automatic normalization approach. The effect of the manual and automatic normalization approaches on diagnostic accuracy of T2-weighted intensities was determined with Receiver Operating Characteristic (ROC) analyses. The Areas Under the Curve (AUC) were compared. The automatic segmentation of multiple reference-tissues was validated with an average DICE score higher than 0.8 in the test phase. Thereafter, the method developed demonstrated that the normalized intensities lead to an improved diagnostic accuracy over raw intensities using the manual approach, with an AUC going from 0.54 (raw) to 0.68 (normalized), and automatic approach, with an AUC going from 0.68 to 0.73. This study demonstrates that multi-reference tissue normalization improves quantification of T2-weighted images and diagnostic accuracy, possibly leading to a decrease in radiologist’s interpretation variability. It is also possible to conclude that this novel T2-weighted MRI normalization method can be automatized, becoming clinically applicable.
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Muniswamy, B. "Tissue culture studies in some varieties of coffee with special reference to embryo and another cultures." Thesis, 2000. http://hdl.handle.net/2009/2872.

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Langberg, Henning. "Response of tendon associated connective tissue to mechanical loading in humans : with reference to the microdialysis technique /." 2007. http://digitool.hbz-nrw.de:1801/webclient/DeliveryManager?pid=2173135&custom_att_2=simple_viewer.

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Huang, Bo-Jun, and 黃柏潤. "Integrated reference system for high-throughput sequence analytic and functional annotation on cross-species and multiple-tissue." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/08177143975815049216.

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碩士<br>國立臺灣大學<br>工程科學及海洋工程學研究所<br>96<br>The biologists expect to use model animal to predict non-model animal when they want to deal with sequence alignment. However, the integrated platform on cross-species and multiple-tissue for gene-protein-function inference is critical according to literature surveys on related service. Without integrated platform, researches have to download files, link the relationships between databases, and develop programs to deal with dataset manually. With the consideration of different species and multiple tissues, the complexity of platform is incredible to deal with multiple data sources for biologists. In addition, function inference for gene sequences could be done by GO (Gene Ontology) term. In this paper, we propose a framework of integrated platform with cross-species and multiple-tissue data reference, and it provides high-throughput sequence analytic tool for homology mapping. In addition, we also develop a web service to integrate different data sources and functional annotation information of GO. Computer science technology is also applied such as XML (Extensible Markup Language) for information exchange to simplify flow combination and dynamic web design and web 2.0 technology for friendly interactive interface to provide enriched information.
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Thammiraju, S. R. "Tissue culture studies in pearl millet [Pennisetum glaucum (L) R. Br.] with special reference to in vitro doubled haploid production." Thesis, 2000. http://oar.icrisat.org/961/1/62765.pdf.

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Hosseini, Afshin [Verfasser]. "Expression of genes related to energy balance in adipose tissue of dairy cattle: effects of SCFA on mRNA abundance as quantified by qPCR and relevance of appropriate selection of reference genes / von Afshin Hosseini." 2010. http://d-nb.info/1010169173/34.

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Wagner, Nathan V. "DXA reference standards for percent body fat and lean body mass in adults." 2013. http://liblink.bsu.edu/uhtbin/catkey/1713809.

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Dual energy x-ray absorptiometry (DXA) provides accurate measurements of percent body fat (%BF) and lean body mass (LBM), however no reference standards currently exist using DXA-derived data. This study’s purpose was to develop reference data sets for DXA-derived %BF and LBM, and to characterize the agreement of obesity classifications between BMI (≥30 kg/m2) and %BF (≥25% for men and ≥30% for women). 2,761 subjects were scanned from 2003-2013 using either the GE Medical Systems Lunar Prodigy or Lunar iDXA. Normative reference tables displaying mean values and select percentiles were created for %BF and LBM across defined age groups for both genders. Mean %BF and LBM closely reflected data from the National Health and Nutrition Examination Survey across age groups in both genders. Agreements between BMI and %BF were 97% when identified as obese and 33% when identified as non-obese. Future research should consider creating a national registry for DXA-derived measurements.<br>School of Physical Education, Sport, and Exercise Science
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Henson, Sonal Prabhulal. "High resolution analysis of genes transcribed in Ixodid tick tissues with special reference to salivary glands of the brown ear tick, Rhipicephalus appendiculatus." Thesis, 2013. http://hdl.handle.net/2263/32958.

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Rahn, Helene. "Semi-quantitative röntgentomographische Untersuchungen zur Biodistribution von magnetischen Nanopartikeln in biologischem Gewebe." Doctoral thesis, 2011. https://tud.qucosa.de/id/qucosa%3A25902.

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Im Rahmen der vorliegenden Dissertationsschrift „Semi-quantitative röntgentomographische Untersuchungen zur Biodistribution von magnetischen Nanopartikeln in biologischem Gewebe“ wurden tomographische Untersuchungen an biologischen Objekten durchgeführt. Bei diesen Objekten handelt es sich um Gewebeproben nach minimal-invasiven Krebstherapien wie zum Beispiel magnetischem Drug Targeting und magnetischer Wärmebehandlung. Der Erfolg dieser Therapien ist sowohl abhängig von der korrekten Verteilung der magnetischen Nanopartikel als auch von der Tatsache, dass diese in der Zielregion in einer ausreichenden Menge vorhanden sind. Das Vorliegen dieser beiden Voraussetzungen ist in der vorliegenden Arbeit untersucht worden. Dabei lag der Schwerpunkt der Arbeit auf der Quantifizierung von magnetischem Material in unterschiedlichen biologischen Gewebeproben mittels Röntgenmikrocomputertomographie (XµCT). Für diesen Zweck wurde ein Kalibrationssystem mit speziellen Phantomen entwickelt, mit dessen Hilfe eine Nanopartikelkonzentration einem Grauwert voxelweise zugewiesen werden kann. Mit Hilfe der Kalibration kann der Nanopartikelgehalt sowohl in monochromatischen als auch in polychromatischen tomographischen Daten im Vergleich zu magnetorelaxometrischen Ergebnissen mit wenigen Prozent Abweichung ermittelt werden. Trotz Polychromasie und damit einhergehenden Artefakten können 3-dimensionale röntgentomographische Datensätze mit einer geringfügigen Konzentrationsabweichung im Vergleich zur quantitativen Messmethode Magnetorelaxometrie semi-quantitativ ausgewertet werden.<br>The success of the minimal invasive cancer therapies, called magnetic drug targeting and magnetic heating treatment, depends strongly on the correct distribution of the magnetic nanoparticles on one side. On the other side it depends on the fact that a sufficient amount of magnetic nanoparticles carrying drugs is accumulated in the target region. To study whether these two requirements are fulfilled motivates this PhD thesis „Semi-quantitative X-ray-tomography examinations of biodistribution of magnetic nanoparticles in biological tissues“. The analysis of the distribution of the magnetic nanoparticles in tumours and other tissue examples is realized by means of X-ray-micro computer tomography (XμCT). The work focuses on the quantification of the magnetic nanoparticles in different biological tissue samples by means of XµCT. A calibration of the tomographic devices with adequate phantoms, developed in the frame of this work, opens now the possibility to analyze tomographic data in a semi-quantitative manner. Thus, the nanoparticle concentration can be allocated voxel-wise to the grey values of the three-dimensional tomographic data. With the help of calibration of the tomography equipments used, polychromatic as well as monochromatic three-dimensional representations of objects can be analyzed with regard to the biodistribution of magnetic nanoparticles as well as with regard to their quantity. The semi-quantitative results have been compared with results obtained with a quantitative measurement method magnetorelaxometry (MRX). Thereby a good agreement of the semi-quantitative and quantitative data has been figured out.
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