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1

Nadeau, Cheryl. "A statistical comparison of fingerstick and routine laboratory prothrombin time and international normalized ratio (INR) measurements /." Staten Island, N.Y. : [s.n.], 1998. http://library.wagner.edu/theses/nursing/1998/thesis_nur_1998_nadea_stati.pdf.

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2

Balzan, Silvio Márcio Pegoraro. "Avaliação de critério pós-operatório de insuficiência hepática como fator prognóstico de mortalidade após hepatectomia: importância da alteração combinada do tempo de protrombina e da bilirrubina sérica." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/5/5154/tde-29012007-170755/.

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INTRODUÇÃO. A definição de insuficiência hepática pós-operatória (IHP) não é ainda padronizada, dificultando a comparação de inovações em procedimentos hepáticos e tornando complexo o uso de possíveis intervenções terapêuticas pós- operatórias em um momento adequado. CASUÍSTICA E MÉTODOS. Entre 1998 e 2002, 775 resecções hepáticas eletivas, dos quais 531 (69%) por doenças malignas e 464 (60%) consistindo em hepatectomias maiores, foram incluídas de maneira prospectiva em um banco de dados. O parênquima hepático não-tumoral foi anormal em 330 pacientes (43%) incluindo esteatose em mais que 30% dos hepatócitos em 107 (14%), fibrose sem cirrose em 237 (43%) e cirrose em 94 (12%). Foi analisado o impacto sobre a mortalidade da ocorrência de tempo de protrombina (TP) menor que 50% e bilirrubina total sérica (BT) maior que 50 µmol/L (3 mg/dl) (critério 50-50) nos dias pós-operatórios (PO) 1, 3, 5 e 7. RESULTADOS. A cinética pós-operatória do TP e da BT foram diferentes. O menor nível de TP foi no primeiro dia pós-operatório (PO) e o pico de BT foi no terceiro dia PO. A tendência ao retorno para valores pré-operatórios destes dois fatores bioquímicos se firmou claramente no quinto DPO. A mortalidade operatória global foi de 3.4% (26 pacientes), incluindo 21 (81%) casos com parênquima não-tumoral anormal e 20 (77%) após uma hepatectomia maior. O índice de mortalidade foi maior em pacientes com TP < 50% ou BT > 50 µmol/L (3 mg/dl) no pós-operatório. A conjunção de TP < 50% e BT > 50 µmol/L (3 mg/dl) no quinto DPO foi potente fator preditivo de mortalide, a qual atingiu 59% quando esta associação ocorreu. CONCLUSÕES. A partir do quinto dia PO, a associação de TP > 50% e BT > 50 µml/L (3 mg/dl) (critério 50-50) foi preditor prático e acurado de índice de mortalidade após hepatectomia. Propõe-se assim este critério como definição de insuficiência hepática pós-operatória.
INTRODUCTION. Definition of postoperative liver failure (PLF) is not standardized, rendering complex the comparison of novelties in liver procedures and also the use of possible postoperative therapeutic interventions in due time. METHODS. Between 1998 and 2002, 775 elective liver resections, whence 531 (69%) were for malignancies and 464 (60%) for major resections, were included in a prospective database. The non- tumorous hepatic parenchima was abnormal in 330 patients (43%) including steatosis > 30% in 107 (14%), non-cirrhotic fibrosis in 237 (43%) and cirrhosis in 94 (12%). The clinical impact of Prothrombin Time (PT) < 50% and Serum Bilirubin (SB) > 50µmol/L (3 mg/dl) (50-50 criteria) on postoperative days (POD) 1, 3, 5 and 7 was analyzed. RESULTS. Kinetic of postoperative PT and SB were different. Lowest PT levels were on POD1 and the peak of SB was on POD 3. The tendency to return to preoperative values of these two biochemical factors was clearly affirmed on POD 5. Operative mortality was 3.4% (26 patients), including 21 (81%) cases with abnormal liver parenchyma and 20 (77%) following major hepatectomies. Mortality rate was increased in patients with PT < 50% or SB > 50µmol/L (3mg/dl). The conjunction of PT < 50% and SB > 50µmol/L (3 mg/dl) on POD 5 was a strong predictive factor of increased mortality, which reached 59%. CONCLUSIONS We found that after postoperative day 5, the association of PT > 50% and SB > 50µml/L (3 mg/dl) (50-50 criteria) was a simple and accurate predictor of mortality after hepatectomy. These results allow us to propose this criteria as a definition of postoperative liver failure.
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3

Karlsson, Jessica. "Sample cradle prevents pre-analytic error on platelet counts but is not essential for hemoglobin measurement and prothrombin time." Thesis, Uppsala universitet, Institutionen för medicinsk biokemi och mikrobiologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-182146.

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Introduction: It is recommended to place all the vacuum tubes directly on a sample cradle after vein puncture to prevent analytic error. This recommendation is not always easy to follow because the samples are taken by different professionals under different situations.  The three most common analyses, platelets count, haemoglobin and prothrombin time were tested.  Therefore, it was interesting to compare results from the three most common analyses with or without sample cradle, to evaluate the influence of this step on the result. Methods: Three analyses were preformed, using blood from 50 different persons. Each person gave two vacuum tubes, each contained 4.5mL of venous blood for the study. Tubes containing EDTA were used for platelet counts and measurement of haemoglobin and tubes containing citrate were used for prothrombin time-analysis. One of the tubes was placed, as recommended, directly on the sample cradle while the other tube was placed flat on a bench for 10 minutes before it was placed on the sample cradle. Results: There was a clear difference in platelet counts with and without immediate cradling but only minor difference between the results for haemoglobin and International Normalized Ratio. Conclusion: Some analyses seem to be more sensitive for variation in cradling than others. For platelet count it was important to immediately rock the tubes but for determination of prothrombine time and hemoglobin it had a small impact. The small impact on the results is probably due to the efficiency of the anticoagulant in the vacuum tubes.
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4

Sousa, Ivancia Donato de Luna. "Estudos hemostáticos secundários causados pela peçonha bruta, frações proteicas e proteínas isoladas da peçonha de Crotalus durissus terrificus." Universidade Federal da Paraíba, 2017. http://tede.biblioteca.ufpb.br:8080/handle/tede/9414.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Snakebites (Ophidism) are listed by the World Health Organization as a neglected tropical disease and are considered a public health problem. Among the activities triggered by envenoming from Crotalus durissus terrificus snake venom, the coagulant one is intriguing and contradictory, curious and contradictory, since the venom has, in its composition, coagulation precursor proteins and anticoagulant proteins. The present work describes, in vitro, the performance of crude venom, protein fractions and purified proteins of Crotalus durissus terrificus venom on the coagulation factors of human plasma secondary hemostasis. The coagulant and / or anticoagulant activity of crude venom, protein fractions and purified proteins were evaluated directly on human citrated plasma. Changes in Prothrombin Time (PT) and Activated Partial Thromboplastin Time (APTT) were measured with commercial kits. Clots formed in the presence of crude venom, protein fraction # 7 and Gyroxin displayed as a hyaline flexible mass and steady state. The evaluation of the clot formation time in the presence of the protein fractions # 1 to # 6 and isolated proteins (Crotoxin complex, Crotoxin A, Crotoxin B and Crotamine), after the commercial tests (PT and APTT), allowed to infer that these proteins interfere in all pathways of the coagulation cascade. Therefore, the Crotoxin A, Crotoxin B, Crotoxin and Crotamine proteins may act similarly to some anticoagulants direct inhibitors of thrombin, factor Xa and antithrombin III activator. Moreover, Crotoxin B can inhibits the formation of the prothrombinase complex by direct interaction with factor Xa. Consequently, the protein content from C. d. terrificus snake venom can act synergistically in coagulation and dysfunction and / or inhibition of natural anticoagulants unbalancing hemostasis.
Acidentes ofídicos (ofidismo) são listados, pela Organização Mundial de Saúde, como doença tropical negligenciada e são considerados um problema de saúde pública. Dentre as atividades desencadeadas pelo empeçonhamento por Crotalus durissus terrificus, a coagulante é curiosa e contraditória, pois a peçonha apresenta, em sua composição, proteínas precursoras da coagulação e proteínas anticoagulantes. O presente trabalho descreve, in vitro, a atuação da peçonha bruta, de frações proteicas e proteínas purificadas da peçonha de Crotalus durissus terrificus sobre os fatores de coagulação da hemostasia secundária do plasma humano. A atividade coagulante e/ou anticoagulante da peçonha bruta, frações proteicas e proteínas purificadas foram avaliadas diretamente sobre o plasma citratado humano e as alterações no Tempo de Protrombina (TP) e no Tempo de Tromboplastina Parcial Ativada (TTPA) foram aferidos com kits comerciais. Os coágulos formados na presença da peçonha bruta, da fração proteica #7 e da Giroxina apresentaram-se como uma massa hialina de textura flexível e pontual. A avaliação do tempo de formação dos coágulos na presença das frações proteicas #1 até #6 e das proteínas isoladas Crotoxina, Crotoxina A, Crotoxina B e Crotamina, após a aplicação dos testes comerciais (PT e APTT), possibilitou inferir que essas proteínas interferem em todas as vias da cascata de coagulação. Por conseguinte, as proteínas Crotoxina A, Crotoxina B, Crotoxina e Crotamina podem atuar de forma semelhante a alguns anticoagulantes inibidores direto de trombina, do fator Xa e do ativador da antitrombina III. Ainda, a Crotoxina B pode inibir a formação do complexo protrombinase por interação direta com o fator Xa. Consequentemente, o conteúdo proteico da peçonha de C. d. terrificus pode atuar de forma sinérgica na coagulação e na disfunção e/ou inibição dos anticoagulantes naturais desequilibrando a hemostasia.
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5

Osman, Abdimajid. "Studies on warfarin treatment with emphasis on inter-individual variations and drug monitoring." Doctoral thesis, Linköping : Linköping University, 2007. http://www.bibl.liu.se/liupubl/disp/disp2007/med1000s.pdf.

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6

Dias, Marinês Lavall. "AVALIAÇÃO DO FIBRINOGÊNIO, TEMPO DE PROTROMBINA TEMPO DE TROMBOPLASTINA PARCIAL ATIVADA E FATORES DE RISCO EM PACIENTES COM INFARTO AGUDO DO MIOCÁRDIO." Universidade Federal de Santa Maria, 2006. http://repositorio.ufsm.br/handle/1/6050.

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It was looked to stand out the importance of discover laboratorial parameters that are auxiliary to the diagnostic of acute infarction of myocardial (AMI). The AMI is one of the biggest problems of public health in the world. Due to this fact, it is of major importance to find laboratorial parameters with quality and reasonable costs. In the present study fibrinogen concentrations measured during acute phase of AMI were related to cardiovascular death or a new AMI event. This incidence was higher in the etary range of 44 to 75 years in men; and 56 to 90 in women. Approximately 73% of patients presented familiar history of Coronary Heart Disease (CHD), 66% smoked, 63% presented hypertension and 81% sedentary. It was also observed elevated cases of AMI in extreme temperature days. For the fibrinogen concentrations (FBR), results demonstrated significant difference (p<0.05) between the control and infarction group patients. For protrombin time, troponine (TROP), creatinokinase, CK-MB and leukocytes count, results showed statically difference between groups. However, TTPa, total cholesterol, HDL, LDL, triglycerides levels presented no significant difference between studied groups. In conclusion, this work demonstrated a increasing fibrinogen concentration in patients with AMI, revealing that it may be adequate as a cardiac marker for AMI.
Procurou-se ressaltar a importância de determinados parâmetros laboratoriais que auxiliem o diagnóstico do infarto agudo do miocárdio (IAM). O IAM é um dos maiores problemas de saúde pública no mundo. Devido a isso, torna-se importante encontrar parâmetros laboratoriais de qualidade e baixo custo, para a caracterização do IAM. Concentrações altas de fibrinogênio determinados durante a fase aguda do IAM, foram associadas com morte cardiovascular ou um novo evento de IAM. A incidência de IAM é maior em homens na faixa etária de 44 a 75 anos; e nas mulheres entre 56 a 90 anos. Dos pacientes avaliados neste estudo, 73% apresentavam história familiar de doença arterial coronariana (DAC); 66% fumavam, 63% apresentavam hipertensão e 81% era sedentária. Foi observado que nos dias frios ou com temperaturas extremas aumentou o número de IAM. Para as concentrações de fibrinogênio (fbr), tempo de protrombina (TP), tempo de tromboplastina ativada (TTPa), troponina (TROP), creatinoquinase (CK), creatinoquinase fração MB, CK-MB, contagem de leucócitos, a média dos resultados obtidos apresentou diferença significativa entre os grupos controle e infartados. No entanto para o TTPa, colesterol total, HDL, LDL, triglicerídeos as médias observadas não apresentaram diferença significativa. Neste trabalho foi possível observar o aumento da concentração de fibrinogênio e no tempo de protrombina dos pacientes com IAM.
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7

Ferreira, Caroline Marcondes. "Potencial de geração de trombina e sua relação com o tempo de protrombina em pacientes com cirrose." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/5/5168/tde-27022019-145125/.

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Introdução: Pacientes com cirrose possuem altos níveis de fator VIII e preservação da trombomodulina (TM) (ativador da proteína C) apesar da redução global nas concentrações dos procoagulantes e anticoagulantes naturais. Isto não é levado em conta no teste de TP/INR, o qual não requer a adição de trombomodulina. Deste modo, o TP/INR não é capaz de demonstrar a magnitude da geração de trombina, em condições similares à que ocorre in vivo. De fato, o teste de TP/INR mede o lado procoagulante e se correlaciona com somente 5% do total de trombina gerada. Nossa hipótese é que a geração de trombina está bem preservada na cirrose, ainda que avançada, apesar dos resultados anormais do TP/INR, os quais indicariam coagulopatia. Objetivo: correlacionar os resultados do teste TP/INR com a geração de trombina nos pacientes com cirrose após procedimento invasivo (ligadura elástica de varizes esofagianas - LEVE). Pacientes e métodos: 97 pacientes foram consecutivamente incluídos no estudo (58 homens; 54±10 anos) e divididos em dois grupos INR < 1,5 e INR >= 1,5. Todos os pacientes passaram por uma criteriosa análise clínica e laboratorial, que incluiu revisão dos prontuários, determinação do TP/INR e da geração de trombina (ETP) com e sem adição de trombomodulina e cálculo do rETP (razão dos resultados com e sem adição de trombomodulina). Resultados: Não houve diferença significante na média dos valores de ETP sem trombomodulina no grupo INR < 1,5 (n=72), que foi 1.250±315,7 nmol/min quando comparada ao grupo INR >= 1,5 (n=25), cujos valores foram 1.186±238 nmol/min, p=0,3572. Após adição de trombomodulina, os valores mudaram para 893,0±368,6 e 965,9±232,3 nmol/min, respectivamente (p=0,6265). Ambos os grupos apresentaram preservação da geração de trombina, com valores mais elevados no grupo INR >= 1,5 do que no grupo de pacientes com INR < 1,5 (rETP 0,81±0,1 versus 0,69±0,2; p=0,0042). Evidência de hipercoagulabilidade (valores altos de rETP) foi demonstrada em 80% dos pacientes. Mesmo pacientes com INR >= 1,5 apresentam geração de trombina preservada, o que justificaria a baixa prevalência de sangramento após ligadura elástica de varizes esofagianas (5,2%; 3 pacientes no grupo INR < 1,5 e 2 pacientes no grupo INR >= 1,5). Conclusões: a geração de trombina se encontrou preservada nos pacientes com cirrose e os valores anormais de INR não refletiram a ocorrência de sangramento. A maioria dos pacientes mostrou evidência de hipercoagulabilidade, apesar do INR alargado. Sangramento após LEVE ocorreu em pequena parcela dos pacientes e não foi relacionado ao status da coagulação
Introduction: Patients with cirrhosis have higher levels of factor VIII and preservation of endothelial thrombomodulin (protein C activator) in spite of the global reduction in procoagulant and natural anticoagulant concentrations. This is not taken into account in the laboratory test of INR/PT, which does not require the addition of thrombomodulin and, thus, is not able to emulate the generation of thrombin that happens in vivo. In fact, INR/PT is a measure of procoagulant status and correlates with only 5% of the total amount of generate thrombin. We hypothesized that thrombin generation is well preserved in cirrhosis, even in advanced stages, despite the abnormal result of INR/PT, which would indicate coagulopathy. Aims: to correlated INR/PT with thrombin generation in patients with cirrhosis in the elective setting of an invasive procedure (endoscopic variceal ligation- EVL). Patients and Methods: 97 consecutive patients were prospectively included in this study (58 men; 54±10 years old) and divided into two groups INR < 1.5 and INR >= 1.5. All patients underwent a stringent clinical and laboratory assessment which included review of the clinical chart, INR/PT determinations and assessment of endogenous thrombin potencial (ETP) without and with the addition of thrombomodulin and calculation of the ETP ratio (rETP= without/with thrombomodulin). Results: There was no significant difference in the mean value of ETP without thrombomodulin that was 1,250±315.7nmol/min for patients with INR < 1.5 (n=72) and 1,186±238 in those with INR >= 1.5 (n=25); p= 0.3572. After the addition of thrombomodulin, values changed to 893.0±368.6 and 965.9±232.3, respectively (p= 0.6265). Both groups had preserved thrombin generation, which was higher in patients with INR >=1.5 than in patients with INR < 1.5 (rETP 0.81±0.1 versus 0.69±0.2; p=0.0042). Evidence of hypercoagulability (high rETP) was demonstrated in 80% of patients. Even patients with INR >= 1.5 had preserved thrombin generation, which is likely to account for the low prevalence of post-EVL bleeding (5.2%; n=3 with INR < 1.5 and n=2 with INR >= 1.5). Conclusions: thrombin generation was well preserved in patients with cirrhosis and was not reflected by abnormal results of INR. Most of the patients had evidence of hypercoagulability, despite enlarged INR. Post-procedure bleeding occurred in a small subset of the patients and was not related to the coagulation status
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Hsieh, Yao-Chih, and 謝曜至. "A Fully Integrated Prothrombin Time Test on the Centrifugal Platform." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/95891370880562565932.

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碩士
逢甲大學
化學工程學系
104
The purpose of this work is to improve the microfluidic functions and the stability and accuracy of the test results by studying the fluid flow behavior of decanting process for various properties of fluid. In the past, a centrifugal analyzer was successfully developed, which is able to conduct whole blood separation, plasma decanting, mixing with the reagents, and present the test results within a few minutes. However, it still had some problems need to be solved such as tedious liquid loading and the instability of decanted volume for plasma decanting. To deal with above-motioned problem, we conducted a systematic study to figure out the mechanism of decanting process in order to develop a more robust microfluidic functions, especially for the blood and reagent decanting. In addition, we improving the analyzer by developing the reagent storage techniques and the double-layer aliquoting structure. The user only need to load the whole blood sample and water into the reservoirs individually. An automated blood coagulation test, which is able to yield consistent test results, can be achieved using this system.
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Wu, Jia-Huei, and 吳家慧. "Development of Centrifugal Platforms for Prothrombin Time & Immunoreaction Tests." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/92261466137956235012.

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碩士
逢甲大學
化學工程學所
98
The first goal of this study is to develop a microfluidic disc platform for conducting prothrombin time tests with low liquid volume. Prothrombin time is a sensitive test for oral anticoagulant therapy. Patients taking too much or too little anticoagulants may cause bleeding or blood clotting. Therefore, these patients need to monitor the prothrombin time of their blood regularly after taking oral anticoagulants. Literatures also showed that patients under intensive monitoring can improve their survival rate. In this study, prothrombin time tests were performed on a microfluidic disc platform, which including microfluidic disc, motor control and optical detection system. 101 clinical samples were tested by the microfluidic disc analyzer and the automated blood coagulation analyzer (Sysmex CA1500), which is the instrument currently used in Taichung Veterans General Hospital. The test results showed that there is a high correlation and good agreement between the two instruments. The microfluidic disc analyzer we developed demonstrated good portability and is friendly to use. In addition, the volume of the reagent and plasma required for the microfluidic disc analyzer is only 10 percent of volume required for the Sysmex CA1500. The second goal of this study is to develop a surface modification techniques used for ovarian cancer (CA 125) detection. Various surface modification techniques were carried out on a PMMA substrate and its ability for the antibody adsorption is measured. The experimental results showed that antibody adsorption on a surface of TEOS modified PMMA is equivalent to the one on the surface of a microtiter plate. In addition, it is superior to pristine PMMA, allylamine plasma treated PMMA, as well as PEI modified PMMA.
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Cheng, Jen-Hao, and 鄭人豪. "Development of a POC Prothrombin Time Test Device on Microfluidic Discs." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/77014700304315770856.

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碩士
逢甲大學
化學工程學所
95
Prothrombin Time (PT) test is a sensitive monitoring test for oral anticoagulant therapy. Patients with heart and other diseases may take blood-thinning drugs to prevent clotting. These drugs have a “narrow” therapeutic range; Too much blood thinner can cause hemorrhage, while too little can allow clots to form and obstruct blood vessels, causing stroke or death. Patients taking oral anticoagulant therapy usually had a PT test every one or two months during the regular visit to their doctors. By using an in-home test kit, they can test themselves as often as their doctors recommended. In this research project, a point-of-care PT test on a microfluidic disc analyzer is developed with the integration of motor control, optical property measurement and microchannels. Both dry and wet reagent methods were conducted and the test results were compared with the ones measured by Sysmex CA-500. The experimental results showed good repeatability for both methods. However, the experimental results also showed that the prothrombin time measured by the dry reagent method is longer than the wet reagent method. The reason for this deviation was discussed and it was found that the activity of the dry reagent, the mixing efficiency in the microchannel and the solubility of the PT reagent play important roles on the extension of the prothrombin time.
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Liao, Hong-Song, and 廖宏崧. "Capillary Effect of Microfluidic Mixer and Its Application on Prothrombin Time Tests." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/h7nqv7.

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碩士
國立虎尾科技大學
自動化工程研究所
102
The purpose of this study is to design a passive micromixer on microfluidic chip that performs plasma mixing function. Capillary action is an effective way to driving a liquid into a microfluidic channel. Owing to the strong capillary force, plasma was introduced into the microfluidic channel without any external driving force. Experiments are performed to investigate the mixing performance of three microfluidic mixers with square-wave, curved and zig-zag microchannels, respectively. Of the three microchannels, the square-wave microchannel is found to yield the best mixing performance, and is therefore selected for design optimization. Four microfluidic micromixers incorporating square-wave PDMS microchannels with different widths in the x- and y-directions are fabricated using conventional photolithography techniques. The results show that given an appropriate specification of the microchannel geometry, a volume flow rate of 0.59 μl/s and a mixing efficiency of more than 76% can be obtained within 3.7 s. The practical feasibility of the proposed device is demonstrated by performing a prothrombin time (PT) test. It is shown that the time required to perform the PT test using the proposed microfluidic mixer is 12.5 s.
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Wei-kunLin and 林堃維. "Development of Prothrombin Time Tests on a Centrifugal Platform Based on Alternate Spinning." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/91262198114845011519.

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Cheng-WeiChou and 周承緯. "Evaluation of a novel portable optical-based coagulation detector for testing whole blood prothrombin time." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/98373634785220436939.

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碩士
國立成功大學
醫學檢驗生物技術學系碩博士班
100
Prothrombin time (PT), testing the function of coagulation factors in the extrinsic and common pathways, is used to monitor the safe range of anticoagulants for avoiding spontaneous hemorrhage. Point-of-care testing (POCT) devices monitoring PT on-site might be much effectively benefit to the patients receiving anticoagulant therapy. In this study, a novel portable optical-based coagulation detector was designed for POCT whole blood (WB) PT test and was compared to the automatic ACL TOP coagulation analyzer. The portable coagulation detector detected the light transmittance of WB, which was decreased during coagulation process and the PT time was determined as the time of the maximum speed point from first-order derivative of coagulation curve. The results showed that the manual WB PT after the adjustment of the sample volume was highly correlated with plasma PT by either the manual method (r=0.996, p〈0.001, n=20) or the ACL TOP coagulation analyzer (r=0.980, p〈0.001, n=60). The result also showed that WB PT was significantly faster in the low (〈35%) hematocrit (HCT) samples (n=32 average difference=-2.2±2.2s) comparing to normal (36-50%) HCT samples (n=28 average difference=-0.1±0.6s). An acrylic black box encircled the electric circuit was made to reduce the environmental effect. Additionally, the parameters for testing chamber and the ratio of WB to reagent were optimized. Finally, 167 WB samples were tested with our portable WB coagulation detector. It showed that PT of 153 of 167 samples (91.6%) was determined successfully, and WB PT results obtained from portable coagulation detector were highly correlated with manual WB PT (r=0.985, p〈0.001) and ACL TOP plasma PT (r=0.948, p〈0.001). Fibrinogen (FIB) and complete blood count data, including white blood cell, red blood cell, hemoglobin, HCT, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, red cell distribution width and platelet, were used to discover the substances in WB that affected the detection of WB coagulation. Only RBC and FIB were found to affect the pattern of coagulation curve. Increasing RBC number might enhance RBC aggregation which causes a more conspicuous turning point on coagulation curve, and increasing FIB enlarged the signal at maximum speed of clotting time. Moreover, the amount of RBC also cause the difference of PT between WB and plasma sample, which indicates WB coagulation test might be able to predict the coagulation function in vitro more precisely than plasma. In conclusion, the designed portable optical coagulation detector can determine the WB PT time, and the results were highly comparable with clinical reports. WB coagulation tests might be suitable for evaluation of coagulation function.
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14

Nkunjana, Thobela. "The effect of homeopathically prepared Arnica Montana 6C on bleeding, prothrombin and activated partial thromboplastin times in Vivo." Thesis, 2012. http://hdl.handle.net/10210/6025.

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Abstract:
M.Tech.
Haemostasis is an internal mechanism to stop bleeding from a damaged blood vessel. Conceptually this process occurs in a number of essential steps following tissue injury. Although the herbal preparation of Arnica montana has been well documented for its tendency to prolong bleeding, according to the Law of Similars, homeopathically prepared Arnica montana 6C is well indicated for traumatic injuries and post surgical bruising. Arnica montana 6C can be used when there is mechanical trauma that causes wounds, haemorrhages, haematomas, sore-bruised bone and muscular pains, inflammations, fractures, muscular strains and sprains. The remedy is often prescribed before and immediately after surgery to reduce post-operative pain and to speed up recuperation. Three in vitro studies conducted at the Technikon Witwatersrand (now the University of Johannesburg) on various potencies of homeopathically prepared Arnica montana showed lowered overall coagubility of blood, but no significant difference between the experimental and control groups. Bengsch (2000), Hohl (2005), Vermeulen (2000) and van Tonder (2005) recommended that studies on the effect of homeopathically prepared Arnica montana on blood coagulability be repeated in vivo. This study formed part of a three part in vivo study to determine the effect of Arnica montana homeopathic preparations on blood coagulation by measuring the Bleeding Time (BT), activated Partial Thromboplastin Time (aP'TT) and Prothrombin Time (PT). This study investigated the effect of Arnica montana 6C on these measurements. Eighty participants were allocated a participant number and randomised by the research supervisor into four groups of twenty participants. Twenty participants were in the placebo group that was shared by all three studies. Twenty participants were allocated to the experimental group for this study. The study was conducted over a period of two weeks at the University of Johannesburg (UJ) Doomfontein Campus Homeopathy Health Centre. Consenting participants were screened by means of a questionnaire (Appendix D) regarding relevant medical history and other background information. A case history was taken and a physical examination was performed. Any prospective participants that were diagnosed with and/or suffer from hypertension, hypotension, heart disease, a iii bleeding disorder, anaemia, iron or any vitamin deficiency, liver disease, malaria or are currently on aspirin or anticoagulants (Appendix D) were excluded from the study. The bleeding time was measured by a trained medical technologist using a standardised bleeding time technique. Blood samples drawn by a phlebotomist went for coagulation tests comprising of aPTT and PT at the NHLS Main Haematology laboratory of the Johannesburg Hospital. Twenty participants were given a 25mL bottle of Arnica montana 6C in 20% ethanol. Twenty participants received an identical bottle containing only 20% ethanol. All participants were requested to take ten drops twice a day for two weeks. All three coagulation test measurements were performed again at the end of the second week. The BT, PT and aPTT results were analysed by using ordinary descriptive statistics such as mean and standard deviation. Changes over time in blood coagulation were ascertained utilising ANOVA (analysis of variance). The results showed that there is no statistically significant difference between the experimental and control group in BT, aPTT and PT. There was also no statistically significant difference between the first BT, PT and aPTT before medication and the second BT, PT and aPTT after two weeks of medication. The results of the study support the hypothesis that Arnica montana 6C would have no effect on the bleeding or coagulation times in vivo. These results support the view that prescribing the remedy before surgery is not likely to increase the post surgical risk of haemorrhage
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15

Neaves, Alicia Louise. "An in vivo study of the effects of Arnica montana 30C on blood coagulation by measuring : prothrombin, activated partial thromboplastin and bleeding time." Thesis, 2014. http://hdl.handle.net/10210/11905.

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Abstract:
M.Tech. (Homoeopathy)
Haemostasis is defined as the arrest of bleeding by formation of a haemostatic plug or clot. The herb Arnica montana interferes with this process thus resulting in increased bleeding. Homoeopathic physicians use Arnica montana in a potentised form for the treatment of post-operative swelling, pain and ecchymosis but little is known on what effect this potentised form of Arnica montana has on blood coagulation and bleeding time. This study forms part of a three part in vivo study to determine the effects of various homoeopathic potencies of Arnica montana on blood coagulation. This was done by measuring the Bleeding Time (BT), activated Partial Thromboplastin Time (aPTT) and the International Normalised Ratio (INR) of Prothrombin Time (PT). The aim of this particular study is to investigate the in vivo effect of Arnica montana 30C on blood coagulation and Bleeding Time. This study is a double blind, placebo controlled study that took place over a period of two weeks. A total sample group for the three part study consisted of eighty healthy participants between the ages of eighteen to thirty five. Consenting participants that met the criteria were randomised into four groups of twenty each. One group for each part of the three part study were the experimental group and one group was allocated to the placebo group that was shared by all three studies. BT was taken as well as blood samples which underwent coagulation tests (aPTT and INR). Twenty participants received Arnica montana 30C in 20% ethanol and twenty participants received an identical bottle containing 20% ethanol. After two weeks another blood sample was taken where all three coagulation test measurements were repeated. The results of the BT, INR and aPTT were analysed using Statkon Statistical Package for Social Sciences. This showed no statistical difference between the experimental or control group with regard to BT, INR and aPTT. The results indicate that Arnica montana 30C appears to have no effect on Bleeding Time..
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