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Literatura académica sobre el tema "Retrospective operation"

Autor: Grafiati

Publicado: 4 de junio de 2021

Última modificación: 5 de febrero de 2022

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Artículos de revistas sobre el tema "Retrospective operation"

Suhardja, TS, L. Bae, EZ Seah, P. Cashin y DG Croagh. "Acute surgical unit safely reduces unnecessary after-hours cholecystectomy". Annals of The Royal College of Surgeons of England 97, n.º 8 (1 de noviembre de 2015): 568–73. http://dx.doi.org/10.1308/rcsann.2015.0035.

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Introduction The acute surgical model has been trialled in several institutions with mixed results. The aim of this study was to determine whether the acute surgical model provides better outcomes for patients with acute biliary presentation, compared with the traditional emergency surgery model of care. Methods A retrospective review was carried out of patients who were admitted for management of acute biliary presentation, before and after the establishment of an acute surgical unit (ASU). Outcomes measured were time to operation, operating time, after-hours operation (6pm – 8am), length of stay and surgical complications. Results A total of 342 patients presented with acute biliary symptoms and were managed operatively. The median time to operation was significantly reduced in the ASU group (32.4 vs 25.4 hours, p=0.047), as were the proportion of operations performed after hours (19.5% vs 2.5%, p<0.001) and the median length of stay (4 vs 3 days, p<0.001). The median operating time, rate of conversion to open cholecystectomy and wound infection rates remained similar. Conclusions Implementation of an ASU can lead to objective differences in outcomes for patients who present with acute cholecystitis. In our study, the ASU significantly reduced time to operation, the number of operations performed after hours and length of stay.

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Herisson, O., M. Dury, E. Rapp y F. Marin-Braun. "Bilateral carpal tunnel surgery in one operation: Retrospective study". Hand Surgery and Rehabilitation 35, n.º 3 (junio de 2016): 199–202. http://dx.doi.org/10.1016/j.hansur.2015.12.012.

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Sharouf, F., A. Baig, I. Bhatti y M. Zaben. "Neurosurgical operation theatre utilization and efficiency: A retrospective audit". International Journal of Surgery 36 (noviembre de 2016): S91. http://dx.doi.org/10.1016/j.ijsu.2016.08.307.

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Richardson, G. E., M. A. Mustafa, C. S. Gillespie, S. M. Keshwara, B. A. Taweel, C. P. Millward, A. I. Islim y M. D. Jenkinson. "P14.66 Re-operation for recurrent meningioma - are we helping patients?" Neuro-Oncology 23, Supplement_2 (1 de septiembre de 2021): ii50. http://dx.doi.org/10.1093/neuonc/noab180.174.

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Abstract BACKGROUND Meningioma is the commonest primary brain tumour. Despite surgery, meningiomas can recur. Surgery is usually the first line treatment for recurrent meningioma. The aim was to determine the risk factors associated with clinical outcomes (performance status, morbidity, mortality, recurrence) following re-operation for recurrence of intracranial meningioma. MATERIAL AND METHODS Retrospective cohort study (1998–2018). Eligible patients had reoperation for local recurrence of a previously operated meningioma. Collected data included baseline clinical and imaging characteristic. Primary outcome measure was performance status after each reoperation. Secondary outcome measures were medical and surgical morbidity, recurrence-free survival (RFS) and overall survival (OS). RESULTS Fifty-eight patients were eligible (37 female, mean age at 1st re-operation 56.1 years (SD=11.6)). Eleven patients (19.6%) had 2 re-operations and 3 patients (5.4%) had 3 re-operations. Median follow up was 128.5 months (IQR=73–194.5). Median time to 1st recurrence and 1st re-operation were 36.5 (IQR=24.3–81.0) and 43.8 months (IQR=20.3–103.4), respectively. Fifteen patients (26.8%) had worse performance status after 1st reoperation, compared to 5.4% (n=3) after the primary operation. Complication rate was 32.1% (n=18) after the primary operation compared to 48.2% (n=27) after 1st reoperation. At primary operation, there were 29 (51.8%) grade 1, 24 (42.9%) grade 2, and 1 (1.8%) grade 3 tumours. Median RFS after first re-operation was 36.5 months (95% CI 29.3–43.9). Median OS was 312 months (95 % CI 257.8–366.2). Increased number of post-operative complications were a risk factor for worsened performance status following reoperation (OR 2.2 [95% CI 1.1–4.6], P=0.029). CONCLUSION Re-operation is associated with a worse performance status and increased risk of complications. Re-operating meningiomas for radiological recurrence without symptoms increases patient morbidity. Shared-care management decision should be made with patients when considering operating for radiological recurrence only.

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Cascarini, L. y D. Tsarouchi. "O.392 Orthognathic surgery: a retrospective study of operation time". Journal of Cranio-Maxillofacial Surgery 36 (septiembre de 2008): S98. http://dx.doi.org/10.1016/s1010-5182(08)71516-6.

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Zhao, Yong, Chengke Liu, Qing Zhang, Changzheng Wang, Bin Sun, Shun Zhang y Bin Zhang. "Retrospective analysis of TACE times after primary liver cancer operation". Chinese-German Journal of Clinical Oncology 11, n.º 8 (agosto de 2012): 460–64. http://dx.doi.org/10.1007/s10330-012-1013-x.

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Shukla, Archana y Sameer Ahmed. "Abdominal incisional hernia: retrospective study". International Journal of Research in Medical Sciences 6, n.º 9 (25 de agosto de 2018): 2990. http://dx.doi.org/10.18203/2320-6012.ijrms20183631.

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Background: Incisional hernia presents as herniation or protrusion occurring along a prior abdominal scar. It is a known complication of abdominal surgery. They are the second most common type of hernia after inguinal hernias. This study was undertaken to study the incidence and various risk factors leading to incisional hernia.Methods: It is a retrospective study done in Gandhi Medical College, Bhopal; Department of Surgery during January 2017 to January 2018. All the cases were analyzed in various aspects like age, sex, relative incidence, clinical presentation, nature of previous operation, site of previous scar, precipitating factors like obesity, wound infection, abdominal distension.Results: The incidence is around 18.5%. Patients in the age group of 30-50 years found to have highest incidence of incisional hernia. Females outnumbered the males with the ratio of 6:1. Incisional hernia was more common in patients with previous history of gynecological operation. Most of the patients presented with incisional hernia in the infra umbilical region.Conclusions: Incisional hernias can be prevented by avoidance of midline incisions, especially in the infra umbilical region. Mesh repair results in less post-operative complications provided drains are used.

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Manganas, Antoine. "La rétroactivité d'une loi à caractère criminel". Chronique de jurisprudence 21, n.º 1 (12 de abril de 2005): 189–200. http://dx.doi.org/10.7202/042370ar.

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The present study deals with two particular aspects of the problem of retrospective operation of criminal statutes. The principle of the retrospective operation of a procedural statute, as will be seen first, bears some exceptions. S. 36 of the Interpretation Act in particular prescribes that the retrospective operation of procedural enactments takes place only to the extent that the new rules of procedure may be adapted to proceedings taken before the new rules came into effect (R. v. Mustapha Ali). Yet, as will be seen subsequently, it is often very difficult to distinguish between an enactment of substantive nature and one of procedural nature in order to give a retrospective operation to the latter only. This difficulty arose particularity after the modifications of the Criminal Code concerning the offence of driving a motor vehicle with more than a specified proportion of alcohol in the blood (R. v. Johnston). After a brief discussion of those two cases, the author suggests that it is the duty of the legislator to indicate in clear terms what the retrospective operation of a new statute will be, in order to avoid many problems of interpretation.

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Mogensen, S. L., T. Jakobsen, H. Christoffersen y N. Krarup. "High Re-Operation Rates Using Conserve Metal-On-Metal Total Hip Articulations". Open Orthopaedics Journal 10, n.º 1 (29 de marzo de 2016): 41–48. http://dx.doi.org/10.2174/1874325001610010041.

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Introduction: Metal-on-metal hip articulations have been intensely debated after reports of adverse reactions and high failure rates. The aim of this study was to retrospectively evaluate the implant of a metal-on.metal total hip articulation (MOM THA) from a single manufacture in a two-center study. Materials and Methods: 108 CONSERVE® MOM THA were implanted in 92 patients between November 2005 and December 2010. Patients had at time of retrospective evaluation their journals reviewed for re-operations and adverse reactions. Results: 20 hips were re-operated (18.4%) at a mean follow up of 53 months. 4 pseudotumors were diagnosed at time of follow up but no substantiated link was made between adverse reactions and re-operations. Conclusion: The high re-operation rates found in this study raised concern about the usage of the MOM THA and subsequently lead to the termination of implantation of this MOM THA at the two orthopaedic departments.

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Boyapati, Raghuram P., Jahnavi Mehta y Paul Norris. "Same day cancellations of elective operations in a tertiary hospital in south-east England: a review of 11 000 patients in 1 year". British Journal of Healthcare Management 26, n.º 1 (2 de enero de 2020): 27–33. http://dx.doi.org/10.12968/bjhc.2019.0029.

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Cancellations of elective operations have negative consequences, both for patients and the NHS. For the latter, reducing waiting times for surgical procedures remains a pressing concern, as does maintenance of adequate staffing. This study aimed to identify factors contributing to the cancellation of elective operations on the day of the procedure in order to suggest measures that could be taken to reduce these incidents. The retrospective details of just over 11 000 patients awaiting theatre admission for elective operations over a period of 1 year were obtained. The reasons behind last-minute operation cancellations were categorised as either patient factors or hospital factors. Data analysis suggested that the number of cancellations could be reduced by scheduling appointments with a senior doctor closer to the operation date.

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Tesis sobre el tema "Retrospective operation"

Schackert, Gabriele, A. Steinmetz, U. Meier y Stephan B. Sobottka. "Surgical Management of Single and Multiple Brain Metastases: Results of a Retrospective Study". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-135123.

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Background: Advancement in diagnosis and treatment of various cancer entities led to an increasing incidence of brain metastases in the last decades. Surgical excision of single and multiple brain metastases is one of the central treatment options beside radiotherapy, radiosurgery and chemotherapy. To evaluate the benefit of surgery with/without whole-brain radiation therapy (WBRT) in single brain metastases and the influence of image guidance for brain metastases resection, 104 patients were retrospectively evaluated for post-operative outcome. Patients and Methods: Between January 1994 and December 1999 150 patients were surgically treated for brain metastases at the Department of Neurosurgery at the Technical University of Dresden. Outcome could be evaluated in 104 patients with respect to special treatment strategies and survival time (69 patients with single and 35 patients with multiple lesions). Results: Most metastases originated from primary lung and breast tumours. Karnofsky performance score improved on average by 10 after surgery. The extent of the extracerebral tumour burden was the main influence on survival time. Patients’ age below 70 years was combined with prolonged survival time (median survival time, MST: 4.5 months vs. 7 months). Patients with solitary cerebral metastasis had a MST of 16 months, whereas patients with singular lesions had a MST of 7 and 4 months, depending on the extent of the extracerebral tumour growth. Additional post-operative WBRT with 30 Gy was combined with an increase in MST in patients with single brain metastasis (surgery + WBRT: MST 13 months; surgery only: MST 8 months). In addition, the rate of recurrent cerebral tumour growth was distinctly higher in the non-WBRT group. Neuronavigation did not significantly improve post-operative survival time. In 80% of patients extracerebral tumour growth limited patients’ survival. Conclusion: Surgery is an initial treatment option in patients with single and multiple brain metastases especially with large tumours (> 3 cm). Post-operative WBRT seems to prolong survival time in patients with single brain metastasis by decreasing local and distant tumour recurrence. Neuronavigational devices permit a targeted approach. Multiple processes can be extirpated in one session without prolonging the hospitalisation time for the patient. However, neuronavigational devices cannot assure complete tumour resection
Hintergrund: Fortschritte in der Diagnostik und Therapie von Krebserkrankungen haben in den letzten Jahrzehnten zu einer steigenden Inzidenz von Hirnmetastasen geführt. Die chirurgische Entfernung singulärer und multipler Hirnmetastasen stellt neben Strahlentherapie, Radiochirurgie und Chemotherapie eine zentrale Therapieoption dar. Um die Wertigkeit der chirurgischen Behandlung von singulären Hirnmetastasen mit/ohne Ganzhirnbestrahlung (WBRT) und den Einfluss der Neuronavigation zu untersuchen, wurden 104 Patienten retrospektiv bezüglich ihres postoperativen «Outcomes» untersucht. Patienten und Methoden: Zwischen Januar 1994 und Dezember 1999 wurden 150 Patienten mit Hirnmetastasen in der Klinik für Neurochirurgie der Technischen Universität Dresden operiert. Das «Outcome » von 104 Patienten konnte bezüglich der verschiedenen Behandlungsstrategien und Überlebenszeit ausgewertet werden (69 Patienten mit singulären und 35 Patienten mit multiplen Läsionen). Ergebnisse: Die meisten Metastasen stammen von Lungen- und Mammakarzinomen. Nach operativer Behandlung verbesserte sich der Karnofsky-Index um durchschnittlich 10. Das Ausmaß der extrazerebralen Tumormasse stellte die Haupteinflussgröße für die Überlebenszeit dar. Ein Lebensalter unter 70 Jahren war mit einer verlängerten Überlebenszeit verbunden (mittlere Überlebenszeit, MÜZ: 4,5 Monate vs. 7 Monate). Patienten mit solitären Metastasen hatten eine MÜZ von 16 Monaten, während Patienten mit singulären Läsionen, abhängig vom Ausmaß des extrazerebralen Tumorwachstums, eine MÜZ von 7 bzw. 4 Monaten aufweisen. Eine zusätzliche postoperative WBRT mit 30 Gy zeigte eine Verbesserung der MÜZ bei Patienten mit singulären Hirnmetastasen (OP + WBRT: MÜZ 13 Monate; OP allein: MÜZ 8 Monate). Gleichzeitig war die Rate der zerebralen Tumorrezidive in der Nicht-WBRT Gruppe deutlich höher. Die postoperative Überlebenszeit wurde durch Verwendung der Neuronavigation nicht signifikant verbessert. In 80% der Patienten limitierte das extrazerebrale Tumorwachstum die Überlebenszeit. Fazit: Bei Patienten mit singulären und multiplen Metastasen stellt die initiale chirurgische Tumorentfernung eine Therapiealternative insbesondere bei großen Tumoren (> 3 cm) dar. Eine postoperative WBRT scheint die ÜLZ der Patienten mit singulären Hirnmetastasen durch Begrenzung des Auftretens von Rezidivtumoren zu verlängern. Die Neuronavigation erlaubt eine gezielte Zugangsplanung. Multiple Prozesse können einzeitig operiert werden, ohne dass die postoperative stationäre Verweildauer verlängert wird. Hingegen wird eine radikale Tumorentfernung durch Verwendung der Neuronavigation nicht gewährleistet
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich

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Schackert, Gabriele, A. Steinmetz, U. Meier y Stephan B. Sobottka. "Surgical Management of Single and Multiple Brain Metastases: Results of a Retrospective Study". Karger, 2001. https://tud.qucosa.de/id/qucosa%3A27621.

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Background: Advancement in diagnosis and treatment of various cancer entities led to an increasing incidence of brain metastases in the last decades. Surgical excision of single and multiple brain metastases is one of the central treatment options beside radiotherapy, radiosurgery and chemotherapy. To evaluate the benefit of surgery with/without whole-brain radiation therapy (WBRT) in single brain metastases and the influence of image guidance for brain metastases resection, 104 patients were retrospectively evaluated for post-operative outcome. Patients and Methods: Between January 1994 and December 1999 150 patients were surgically treated for brain metastases at the Department of Neurosurgery at the Technical University of Dresden. Outcome could be evaluated in 104 patients with respect to special treatment strategies and survival time (69 patients with single and 35 patients with multiple lesions). Results: Most metastases originated from primary lung and breast tumours. Karnofsky performance score improved on average by 10 after surgery. The extent of the extracerebral tumour burden was the main influence on survival time. Patients’ age below 70 years was combined with prolonged survival time (median survival time, MST: 4.5 months vs. 7 months). Patients with solitary cerebral metastasis had a MST of 16 months, whereas patients with singular lesions had a MST of 7 and 4 months, depending on the extent of the extracerebral tumour growth. Additional post-operative WBRT with 30 Gy was combined with an increase in MST in patients with single brain metastasis (surgery + WBRT: MST 13 months; surgery only: MST 8 months). In addition, the rate of recurrent cerebral tumour growth was distinctly higher in the non-WBRT group. Neuronavigation did not significantly improve post-operative survival time. In 80% of patients extracerebral tumour growth limited patients’ survival. Conclusion: Surgery is an initial treatment option in patients with single and multiple brain metastases especially with large tumours (> 3 cm). Post-operative WBRT seems to prolong survival time in patients with single brain metastasis by decreasing local and distant tumour recurrence. Neuronavigational devices permit a targeted approach. Multiple processes can be extirpated in one session without prolonging the hospitalisation time for the patient. However, neuronavigational devices cannot assure complete tumour resection.
Hintergrund: Fortschritte in der Diagnostik und Therapie von Krebserkrankungen haben in den letzten Jahrzehnten zu einer steigenden Inzidenz von Hirnmetastasen geführt. Die chirurgische Entfernung singulärer und multipler Hirnmetastasen stellt neben Strahlentherapie, Radiochirurgie und Chemotherapie eine zentrale Therapieoption dar. Um die Wertigkeit der chirurgischen Behandlung von singulären Hirnmetastasen mit/ohne Ganzhirnbestrahlung (WBRT) und den Einfluss der Neuronavigation zu untersuchen, wurden 104 Patienten retrospektiv bezüglich ihres postoperativen «Outcomes» untersucht. Patienten und Methoden: Zwischen Januar 1994 und Dezember 1999 wurden 150 Patienten mit Hirnmetastasen in der Klinik für Neurochirurgie der Technischen Universität Dresden operiert. Das «Outcome » von 104 Patienten konnte bezüglich der verschiedenen Behandlungsstrategien und Überlebenszeit ausgewertet werden (69 Patienten mit singulären und 35 Patienten mit multiplen Läsionen). Ergebnisse: Die meisten Metastasen stammen von Lungen- und Mammakarzinomen. Nach operativer Behandlung verbesserte sich der Karnofsky-Index um durchschnittlich 10. Das Ausmaß der extrazerebralen Tumormasse stellte die Haupteinflussgröße für die Überlebenszeit dar. Ein Lebensalter unter 70 Jahren war mit einer verlängerten Überlebenszeit verbunden (mittlere Überlebenszeit, MÜZ: 4,5 Monate vs. 7 Monate). Patienten mit solitären Metastasen hatten eine MÜZ von 16 Monaten, während Patienten mit singulären Läsionen, abhängig vom Ausmaß des extrazerebralen Tumorwachstums, eine MÜZ von 7 bzw. 4 Monaten aufweisen. Eine zusätzliche postoperative WBRT mit 30 Gy zeigte eine Verbesserung der MÜZ bei Patienten mit singulären Hirnmetastasen (OP + WBRT: MÜZ 13 Monate; OP allein: MÜZ 8 Monate). Gleichzeitig war die Rate der zerebralen Tumorrezidive in der Nicht-WBRT Gruppe deutlich höher. Die postoperative Überlebenszeit wurde durch Verwendung der Neuronavigation nicht signifikant verbessert. In 80% der Patienten limitierte das extrazerebrale Tumorwachstum die Überlebenszeit. Fazit: Bei Patienten mit singulären und multiplen Metastasen stellt die initiale chirurgische Tumorentfernung eine Therapiealternative insbesondere bei großen Tumoren (> 3 cm) dar. Eine postoperative WBRT scheint die ÜLZ der Patienten mit singulären Hirnmetastasen durch Begrenzung des Auftretens von Rezidivtumoren zu verlängern. Die Neuronavigation erlaubt eine gezielte Zugangsplanung. Multiple Prozesse können einzeitig operiert werden, ohne dass die postoperative stationäre Verweildauer verlängert wird. Hingegen wird eine radikale Tumorentfernung durch Verwendung der Neuronavigation nicht gewährleistet.
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

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Yung, Kam Ming Louisa. "A retrospective study of preventive resin restorations". Click to view the E-thesis via HKUTO, 1994. http://sunzi.lib.hku.hk/HKUTO/record/B38628442.

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容錦明 y Kam Ming Louisa Yung. "A retrospective study of preventive resin restorations". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1994. http://hub.hku.hk/bib/B38628442.

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Burke, Brian. "A Retrospective Study of Operating Room Utilization and Efficiency in a Pediatric Dental Residency Program". VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3367.

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Purpose: The purpose was to assess and understand operating room (OR) utilization and efficiency in a pediatric dental residency program. Methods: A retrospective study was performed using chart extraction from 778 patients completed by both pediatric dentistry faculty (n=7) and residents (n=17) in an ambulatory care setting over a 32 month period (between July 2010 and March 2013). Patterns in OR usage time were determined by documenting various timing metrics (start and stop times for anesthesia, start and stop times for the dental procedure, times for throat pack in and out), noting patient information (age and ASA patient classification status), and creating variables by grouping data by clinical provider type and dental procedure. OR usage time was analyzed using multiple regression to estimate the per-tooth or per-mouth time for each type of procedure. Results: The median procedure time was 75 minutes (range= 1 to 517 minutes). Multiple regression indicated that for the average patient, a faculty member took 63.8 minutes (95% CI = 60.8 to 66.7 minutes) and a resident took 81.9 minutes (95% CI = 78.7 to 85.0 minutes, P<.0001).These results demonstrate that the appropriate scheduling of operating room should be based on the proficiency level of provider as well as the complexity of the dental procedure. Conclusion: This study concludes that pediatric dental operating room planning and scheduling in teaching hospitals should take into account real constraints such as residents’ level of training and skill.

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Mendonça, Ernesto Quaresma. "Tratamento endoscópico versus cirúrgico para adenomas de papila: revisão sistemática e metanálises". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/5/5168/tde-31072017-153717/.

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Objetivos: Avaliar os desfechos da ressecção endoscópica em comparação à cirurgia no tratamento dos adenomas de papila. Métodos: Foi realizada uma revisão sistemática com metanálise de acordo com as recomendações do Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). As bases de dados Medline, Embase, Cochrane, Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), Scopus and Cumulative Index to Nursing and Allied Health Literature (CINAHL) foram escaneadas. Os estudos incluíram pacientes com adenoma de papila e dados de comparação dos tratamentos endoscópico e cirúrgico para os seguintes desfechos: Ressecção primária completa; Sucesso primário; Recorrência; Sucesso final; e Complicações. A análise foi baseada em modelos de efeito randômico e fixo. Resultados: Cinco estudos de coorte retrospectivo foram selecionados, com um total de 465 pacientes. Todos os estudos tinham dados de ressecção primária completa disponível, mostrando uma diferença favorável ao tratamento cirúrgico (Diferença de riscos = -0,22; Intervalo de confiança de 95% = -0,41 a -0,04). Dados de Sucesso primário também foram identificados em todos os cinco estudos. A análise mostrou que a abordagem cirúrgica supera o tratamento endoscópico neste desfecho (DR = -0,13; IC 95% = -0,24 a -0,02). Dados de recorrência foram encontrados em todos os estudos (465 pacientes), com benefício para o tratamento cirúrgico (DR = 0,12; IC 95% = 0,01 a 0,22). Analisando o desfecho de Sucesso final, disponível em todos os estudos, não encontramos diferença entre as duas abordagens terapêuticas (DR = -0,06; IC 95% = -0,15 a 0,04). Três estudos (251 pacientes) apresentaram dados de complicação, e a análise não mostrou diferença entre os tratamentos endoscópico e cirúrgico (DR = -0,15; IC 95% = -0,53 a 0,23), sem a possibilidade de descartar o viés de seleção para este desfecho. Conclusões: Considerando os desfechos de ressecção primária completa, sucesso primário e recorrência na comparação do tratamento cirúrgico com o tratamento endoscópico para adenomas de papila, a abordagem cirúrgica tem resultados significativamente melhores. Com relação ao sucesso final, não houve diferença entre os dois tratamentos. No desfecho das taxas de complicação, esta revisão sistemática não permite uma conclusão confiável devido à presença de alta heterogeneidade e provável viés de publicação nesta comparação
Objectives: To address the outcomes of endoscopic resection compared to surgery in the treatment of ampullary adenomas. Methods: A systematic review and meta-analysis was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. Medline, Embase, Cochrane, Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), Scopus and Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases were scanned. Studies included patients with ampullary adenomas and comparison data considering endoscopic treatment and surgery for the following outcomes: Complete primary resection; Primary success; Reccurence; Final success; and Complications. The analysis were based on both random and fixed effects model. Results: Five retrospective cohort studies were selected, with 465 patients. All five studies had complete primary resection data available, showing a difference that favours surgical treatment (Risk Difference = -0.22, 95% Confidence Interval = -0.41 to -0.04). Primary success data were identified in all five studies too. Analysis showed that surgical approach overcome endoscopic treatment in this outcome (RD = -0.13, 95% CI = -0.24 to -0.02). Recurrence data was found in all studies (465 patients), with benefit for the surgical treatment (RD = 0.12, 95% CI = -0.01 to 0.22). Analyzing the final success outcome, available in all studies, we found no difference between the two therapeutic approaches (RD = -0.06, 95% CI = -0.15 to 0.04). Three studies (251 patients) presented complication data and analysis shown no difference between the approaches (RD = -0.15, 95% CI = -0.53 to 0.23), not discarding the possibility of presence of selection bias for this outcome. Conclusions: Considering complete primary resection, primary success and recurrence outcomes, surgical approach achieves significantly better results. Regarding the final success, there was no difference between the two treatments. Addressing complication data, this systematic review does not allow for a reliable conclusion due to the presence of high heterogeneity and likely publication bias in this comparison

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Sakuma, Luciane Midory. "Estudo de coorte retrospectivo: impacto do tabagismo nos eventos cardiovasculares (infarto agudo do miocárdio; edema agudo de pulmão, arritmia com instabilidade hemodinâmica e morte cardíaca) no perioperatório de operações não cardíacas". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-25062009-100641/.

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I NTRODUÇÃO: Apesar da importância do tabagismo no processo de doença cardiovascular da sociedade moderna, os estudos de avaliação de risco cardíaco pré-operatório não têm demonstrado a associação entre o hábito de fumar (como variável independente) e os eventos cardíacos pós-operatórios. Nestas pesquisas, as variáveis independentes continuam sendo infarto do miocárdio prévio, insuficiência renal crônica, diabetes, angina, idade, dentre outras. OBJETIVO: Avaliar o papel do tabagismo nas complicações cardíacas pós-operatórias de operações não cardíacas. MÉTODOS: Trata-se de uma coorte retrospectiva de um Hospital Geral, onde foram incluídos 1072 pacientes. Estes foram estratificados em Tabagistas Atuais (n=265), Ex- Tabagistas (n=335) e Não Tabagistas (n=472). Os três grupos foram analisados para os desfechos cardiovasculares combinados no pós-operatório (infarto, edema pulmonar, arritmia com instabilidade hemodinâmica, angina instável; morte cardíaca) e mortalidade em 30 dias. Foram usados o teste quiquadrado e Regressão logística, considerando-se p<0,05 como significante. RESULTADOS: Os desfechos cardiovasculares combinados no pós-operatório e a mortalidade em 30 dias foram 71 (6,6%) e 34 (3,2%), respectivamente. Os Tabagistas Atuais e Pregressos apresentaram 53 (8,8%) eventos cardíacos combinados enquanto que os Não Tabagistas 18 (3,8%), p=0,002. Em relação à mortalidade, Tabagistas Atuais e Pregressos apresentaram 26 (4,3%) enquanto que os Não Tabagistas 8 (1,7%), p=0,024. Na análise multivariada, faixa etária, cirurgia de emergência, insuficiência cardíaca, sobrecarga ventricular esquerda, revascularização do miocárdio e extra-sístole ventricular associaram-se independentemente aos eventos cardiovasculares perioperatórios enquanto que faixa etária, cirurgia de emergência, insuficiência cardíaca, alterações laboratoriais, história de hepatopatia, operações por neoplasia e tabagismo se associaram a mortalidade em 30 dias após a operação de alto risco. CONCLUSÃO: Os Tabagistas atuais e pregressos apresentaram mais eventos cardíacos e mortalidade do que os Não tabagistas. Entre as variáveis independentes associadas a eventos cardíacos e mortalidade em 30 dias, o tabagismo Atual foi á única variável modificável detectada.
I NTRODUCTION: Despite the importance of smoking in the process cardiovascular disease in modern society, the assessments of cardiac risk preoperative haven´t demonstrated an association between smoking (as independent variable) and postoperative cardiac events. Generally, in the researches, indicate as independent variables : myocardial infarction, chronic renal failure, diabetes, angina, age, etc. OBJECTIVE: To assess the impact of smoking in postoperative cardiac complications of non-cardiac surgery. METHODS: A retrospective cohort study designed at General Hospital with 1072 patients. The patients were divided into Current Smokers (n = 265), Past Smokers (n = 335) and Nonsmokers (n = 462). The three groups were analyzed for combined cardiovascular outcomes in postoperative (infarction, pulmonary edema; arrhythmia with hemodynamic instability, unstable angina, cardiac death) and 30-days mortality. The chi-square test and logistic regression were used, considering p<0.05 as significant. RESULTS: The combined cardiovascular outcomes in postoperative and 30-days mortality were 71 (6.6%) and 34 (3.2%), respectively. The Current and Past Smokers presented 53 (8.8%) combined cardiac events than Nonsmokers which showed 18 (3.8%), p = 0002. The 30-days mortality, Current and Past Smokers presented 26 (4.3%) while Nonsmokers 8 (1.7%), p= 0024. At multivariate analysis, age, emergency operation, cardiac failure, left ventricular hypertrophy, coronary-artery revascularization and ventricular premature contractions were independent variables associated with postoperative cardiac events. Another hand, age, emergency operation, cardiac failure, left ventricular hypertrophy, operation of cancer, liver failure, and abnormality laboratories tests were independent variables associated with 30-days mortality after surgery. CONCLUSION: There are more cardiac events and high mortality with Current and Past smokers when compared to nonsmokers. Many independent variables were associated with cardiac postoperative cardiac events and 30-days mortality. However, Current Smoking was unique modifiable variable find out.

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Emmanouilidis, Dimitrios. "Retrospektive multifaktorielle Datenanalyse von Akromegalie-Patienten nach mikrochirurgischer transsphenoidaler Operation hinsichtlich des Outcomes entsprechend den aktuellen Kriterien". 2020. https://tud.qucosa.de/id/qucosa%3A76023.

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Als Akromegalie wird die klinische Manifestation eines bestehenden GH-Überschusses und des dadurch resultierenden erhöhten IGF-1-Spiegels bezeichnet. Die weit häufigste Ursache ist das Hypophysenadenom. Zur Diagnosestellung muss dem klinischen Verdacht die biochemische Krankheitsbestätigung folgen. Therapeutische Maßnahme der ersten Wahl ist die Operation, der zweiten die Medikation und der dritten die Bestrahlung. Die Therapie zielt auf die biochemische Remission (GH und IGF-1 normal), aber diese kann nicht immer erreicht werden. Abgesehen vom Fall einer nicht kontrollierten Akromegalie (pathologische GH- und IGF-1-Werte) kann auch eine biochemische Diskrepanz vorkommen. Präoperativer biochemischer Status, Tumorgröße, Tumorinvasivität und Wirkung der prä- oder postoperativen Medikation sowie die Radiotherapie können das Outcome beeinflussen. Ziel der vorliegenden Arbeit war die umfangreiche retrospektive Datenauswertung von Akromegaliepatienten. Auf der Basis des biochemischen Outcomes, welches auf die Effektivität der Therapie hinweist, wurden demographische, tumorassoziierte, medikamentenbedingte und operationsbezogene Daten detailliert analysiert.

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Selokela, Kwena Alfred. "An analysis of De Klerk v Du Plessis 1994 6 BCLR 124 (T) in the light of section 35(3) of the constitution of South Africa Act 200 of 1993". Diss., 1995. http://hdl.handle.net/10500/17711.

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The issue of the vertical /or horizontal operation of the Bill of Rights (chapter 3) is a controversial one. The interim constitution deals with this controversy in a subtle way by avoiding direct horizontal operation of Chapter 3. Instead, it provides for the so-called 'seepage to horizontal relationships' in terms of section35{3). This apparently was a political compromise between the pro-vertical only and the pro-horizontal groups. The human rights history of this country justifies a Bill of Rights that would have both vertical and horizontal operation. However, in section 35 (3) there is potential for the values enshrined in the constitution and Chapter 3, and the spirit hereof, to permeate and filter through the entire legal system in all it's applications. It would seem, however, as demonstrated by the decision in De Klerk v Du Plessis, that the extent to which this filtering process will benefit individuals in their private relations, will depend on the interpretation given to section 35 (3) by the courts. If courts, as it happend in De Klerk's case fail to realise the full import of section 35 ( 3) aspects of the existing law which are unjust could remain and the process of creating a just, open and democratic society will be hampered.
Constitutional, International & Indigenous Law
LL.M.

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Pulskamp, Sara E. "Pre-operative pressure ulcer risk assessment a retrospective study /". 2007. http://proquest.umi.com/pqdweb?did=1414126921&sid=2&Fmt=2&clientId=42585&RQT=309&VName=PQD.

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Thesis (M.A.)--Northern Kentucky University, 2007.
Made available through ProQuest. Publication number: AAT 1447084. ProQuest document ID: 1414126921. Includes bibliographical references (p. 36-37)

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Libros sobre el tema "Retrospective operation"

Private international law and the retrospective operation of statutes: A treatise on the conflict of laws and the limits of their operation in respect of place and time. 2^a ed. Clark, N.J: Lawbook Exchange, 2003.

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United States. Congress. House. Committee on Small Business. Retrospective review: Have existing regulatory burdens on small businesses? : hearing before the Committee on Small Business, United States House of Representatives, One Hundred Thirteenth Congress, first session, hearing held May 8, 2013. Washington: U.S. Government Printing Office, 2013.

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Kyle, Peters y World Bank. Operations Evaluation Dept., eds. Country assistance evaluation retrospective: An OED self-evaluation. Washington, D.C: World Bank, 2005.

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Gupta, Poonam. Country assistance evaluation retrospective: An OED self-evaluation. Washington, D.C: World Bank, 2005.

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Eliminating job-sapping federal rules through retrospective reviews--oversight of the president's efforts: Hearing before the Committee on Small Business, United States House of Representatives, One Hundred Twelfth Congress, first session, hearing held September 21, 2011. Washington: U.S. G.P.O., 2011.

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Aircraft carriers at war: A personal retrospective of Korea, Vietnam, and the Soviet confrontation. Annapolis, Md: Naval Institute Press, 2007.

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Muir, Malcolm. Selections from the U.S. Citizen-Soldier, protector of the homeland: A retrospective look and the road ahead. Lexington, VA: Virginia Military Institute, 2010.

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National Native Title Tribunal (Australia). Native title: A five year retrospective 1994-1998 : report on the operations of the Native Title Act 1993 and the effectiveness of the National Native Title Tribunal. Perth, W.A: National Native Title Tribunal, 1999.

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Bartolo y Friedrich Carl Von Savigny. Private International Law and the Retrospective Operation of Statutes: A Treatise on the Conflict of Laws and the Limits of Their Operation in Respect of Place and Time. Franklin Classics Trade Press, 2018.

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Susan, Breau. Part 2 The Post-Cold War Era (1990–2000), 43 The ECOWAS Intervention in Sierra Leone—1997–99. Oxford University Press, 2018. http://dx.doi.org/10.1093/law/9780198784357.003.0043.

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This chapter analyses the intervention by the Economic Community of West African state forces, known as ECOMOG, into Sierra Leone from 1997-1999. After a brief review of the very complex facts surrounding this intervention and the generally positive reaction from the international community, this chapter reviews the legal justifications for this intervention and tests them against the jus ad bellum existing at that time. Reasons given were the restoration of a democratically elected government, self-defence, humanitarian intervention, intervention by consent or invitation and retrospective authorisation by the Security Council to a regional peacekeeping operation. None of these are found to have met the tests for legality within jus ad bellum. A final justification argues that this case study is a precedent as an African exception to the prohibition on the use of force with delegation or assumption of powers by an African regional organisation. This would be a troubling challenge to the United Nations Charter regime but might well be part of a larger trend of African use of force initiatives.

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Capítulos de libros sobre el tema "Retrospective operation"

Fabian, Claudia. "Authority files in early book cataloguing: their scope and role in European co-operation". En Retrospective cataloguing in Europe, editado por Franz Georg Kaltwasser, 181–86. Berlin, Boston: De Gruyter, 1992. http://dx.doi.org/10.1515/9783111325996-036.

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Coeugniet, E. G. "The Marshall-Marchetti-Krantz-Hirsch-Stolz-Operation: A Retrospective Study". En Gynecology and Obstetrics Urology, 29–32. Berlin, Heidelberg: Springer Berlin Heidelberg, 1994. http://dx.doi.org/10.1007/978-3-642-48717-0_6.

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Tuite, Michael P. y Hoang Dinh Van. "On Exceptional Vertex Operator (Super) Algebras". En Developments and Retrospectives in Lie Theory, 351–84. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-09804-3_16.

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Mason, Geoffrey y Gaywalee Yamskulna. "On the Structure of ℕ $$\mathbb{N}$$ -Graded Vertex Operator Algebras". En Developments and Retrospectives in Lie Theory, 247–74. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-09804-3_12.

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Powers, Richard. "Retrospective: 25 Years Applying Management Science to Logistics". En A Long View of Research and Practice in Operations Research and Management Science, 89–98. Boston, MA: Springer US, 2010. http://dx.doi.org/10.1007/978-1-4419-6810-4_6.

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Rawitscher, George H. "Applications of a Numerical Spectral Expansion Method to Problems in Physics; a Retrospective". En Topics in Operator Theory, 409–26. Basel: Birkhäuser Basel, 2010. http://dx.doi.org/10.1007/978-3-0346-0161-0_16.

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Birn, G. y M. Stallmach. "Is High Dose Nimodipine Therapy Necessary Following Subarachnoid Hemorrhage? A Retrospective Study of 80 Patients with Aneurysmal Subarachnoid Hemorrhage over the Past 2 Years". En Stabilizing Craniocervical Operations Calcium Antagonists in SAH Current Legal Issues, 185–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-75283-4_31.

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Ramesh, Jairam y Muhammad Ali Khan. "Retrospective Operation". En Legislating for Justice, 71–84. Oxford University Press, 2015. http://dx.doi.org/10.1093/acprof:oso/9780199458998.003.0006.

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Froidevaux, Pascal, Max Haldimann y Francois Bochu. "Long-Term Effects of Exposure to Low-Levels of Radioactivity: a Retrospective Study of 239Pu and 90Sr from Nuclear Bomb Tests on the Swiss Population". En Nuclear Power - Operation, Safety and Environment. InTech, 2011. http://dx.doi.org/10.5772/19058.

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Dylan, Huw, David V. Gioe y Michael S. Goodman. "The ‘Slam Dunk’: The CIA and the Invasion of Iraq". En The CIA and the Pursuit of Security, 427–50. Edinburgh University Press, 2020. http://dx.doi.org/10.3366/edinburgh/9781474428842.003.0021.

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This chapter focuses on ‘Operation Iraqi Freedom’, the Iraq War, and one of the key justifications, the claim that Saddam was developing weapons of mass destruction and had to be stopped. Intelligence was crucial to this judgement; but it was wrong. This chapter examines why. It focuses on the challenge of analysis, particularly against mysterious and deceptive targets. How was the CIA to determine that Saddam Hussein had nothing to hide when his actions indicated otherwise? Document: Misreading Intentions: Iraq’s Reaction to Inspections Created Picture of Deception Iraq WMD Retrospective Series.

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Actas de conferencias sobre el tema "Retrospective operation"

Yeh, William W. G. "Optimization of Hydrosystem Operation—A 40-Year Retrospective". En World Environmental and Water Resources Congress 2010. Reston, VA: American Society of Civil Engineers, 2010. http://dx.doi.org/10.1061/41114(371)256.

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Neckel, Claus P. "Vestibuloplasty: a retrospective study on conventional and laser operation techniques". En BiOS '99 International Biomedical Optics Symposium, editado por John D. B. Featherstone, Peter Rechmann y Daniel Fried. SPIE, 1999. http://dx.doi.org/10.1117/12.348330.

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Burshtin, Michael L. "The Pennsylvania Railroad GG1 Electric Locomotive: A Retrospective". En 2020 Joint Rail Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/jrc2020-8002.

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Abstract This paper is a historical review of the design and operation of the Pennsylvania Railroad’s class GG1 electric locomotive over its heavily-trafficked New York City-Washington, DC main line during the period 1934–1983. The locomotive was designed in-house by the railroad in corroboration with Baldwin Locomotive, General Electric and Westinghouse Electric following competitive tests of several electric locomotive designs. Its outstanding performance and long operating life has resulted in it being generally considered the most highly regarded electric locomotive in North America. The Pennsylvania Railroad embarked in the late 1920’s on a major AC electrification program for its New York-Washington and Philadelphia-Harrisburg main lines and local branches. It initially planned to use a fleet of class P5 rigid frame 2-C-2 electric locomotives for service. However problems were quickly encountered with damaging lateral track impacts, axle cracks, truck hunting, and inadequate tractive effort. The railroad responded with a series of competitive evaluation tests of several locomotive designs including a recent New York, New Haven & Hartford (NYNH&H) Railroad articulated frame locomotive, using an ingenious method to measure truck lateral forces. As a result, the railroad developed two prototype electric locomotive designs, a rigid frame class R1 2-D-2 and an articulated frame class GG1 2-C+C-2. Follow-up track testing verified that the GG1 had lower track lateral forces, and was selected for production. The 4,620 hp GG1 combined several significant North American design concepts: - Exceptional power from six double-armature traction motors for heavy passenger train operation at 100 mph; - Double-ended body design to eliminate the need to turn locomotives; - Use of separate truck frames with an articulation joint connection, allowing improved rail tracking and lower lateral forces; - Housing the main transformer and locomotive cabs in the center body, providing increased crew accident protection in collisions; - Use of high voltage Alternating Current (11 kV at 25 Hz); and - One of the first applications of Industrial Design (by Donald R. Dohner and Raymond F. Loewy) producing a streamlined locomotive using a welded carbody. The GG1 was quickly recognized as a rare combination of stellar performance, robust construction, and low maintenance costs. It was used to inaugurate electrified New York-Washington operations, performed admirably during World War II, successfully made the later transition to freight train operation, and was finally retired in October 1983. The prototype GG1 locomotive 4800 has been designated an ASME national engineering landmark.

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"Technique for the Retrospective and Predictive Analysis of Cognitive Errors in Maritime Pilotage Operation". En Maritime Safety International Conference. Clausius Scientific Press, 2019. http://dx.doi.org/10.23977/mastic.033.

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Mackay, M. y C. Edwards. "A Retrospective Analysis of QoS Deployment, Operation and Use in Enterprise and Provider Networks". En 2013 Workshops of 27th International Conference on Advanced Information Networking and Applications (WAINA). IEEE, 2013. http://dx.doi.org/10.1109/waina.2013.26.

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Kerner, Jeff W. y Gary W. Stetler. "Ash Cooling Screws: A Retrospective and Looking Ahead". En 17th International Conference on Fluidized Bed Combustion. ASMEDC, 2003. http://dx.doi.org/10.1115/fbc2003-100.

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The first commercial screw cooler on record for cooling bottom ash from fluidized bed combustion (FBC) boilers was installed in 1979. Since then, over 300 ash screw cooler (ASC) machines have been used for this duty worldwide. The relatively quick upsurge in developing and building FBC boilers in the early 1980’s forced the industry to select existing cooling screw designs, typically used in less severe services in the chemical, grain, plastics and food industry. At the time, these were the only reasonable and readily available machines thought capable of handling abrasive, corrosive and extremely hot bottom ash. The extreme difficulties of operating and maintaining these units in this service quickly became apparent, but only after quite a number of initial designs had already been designed, purchased and installed. Today, 23 years later, both the manufacturers and users of ASC’s can look back and point to installations where, thanks to communication and cooperation between operators and the manufacturer, operating units and their installations have been successfully modified, resulting in smoother operation and much less frequent maintenance. New units can incorporate a range of features, depending upon the anticipated ash quality. As a result, ASC are now reportedly ranked low on the list of FBC operator’s and manager’s concerns. This paper will address what has been learned by both manufacturers and operators. The results of a survey of the operating and maintenance experience as well as maintenance costs of a wide sample of ASC users will be presented. A look ahead as to where ash screw cooler technology is moving is addressed, with help and continued input from current users of the equipment.

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Dachos, John, Peter Tobara y Bernard Ulozas. "Gas Turbine Systems Training in the U.S. Navy: A Retrospective Analysis". En ASME 1988 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1988. http://dx.doi.org/10.1115/88-gt-215.

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Five years after the introduction of gas turbine propulsion in major U. S. Navy combatants, the engineering training pipeline, populated with cross-rates primarily from the existing machinist, engineman, and electrical ratings, consisted of a series of contractor developed block courses operationally centered around the propulsion and electrical control consoles. The rapid introduction of new ships in the late seventies and eighties required an accelerated training pipeline and the use of mostly apprentice candidates directly from recruitment. This increased need, the recognition in the fleet that existing training was not providing system knowledge, and the construction of a gas turbine training hot plant precipitated the development of a new training curriculum. Course development was derived from documentation which dictates plant operation: the equipment/system design; the Preventive Maintenance System (PMS); the Engineering Operating Sequencing System (EOSS); Fleet commander engineering management programs; and the Ships’ Manning Document (SMD). Using a disciplined approach, essential student performance objectives were defined and necessary learning objectives developed from the above documentation. The scope of the course encompassed the “cradle to grave” concept from apprentice training through journeyman and supervisor, and necessitated incremental and refresher training throughout the career of the gas turbine mechanic and electrician.

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Hedges, A. R., C. J. Parker y V. V. Kakkar. "DOES LOW-DOSE PERI-OPERATIVE HEPARIN ADMINISTRATION AFFECT MORTALITY FOLLOWING MAJOR ABDOMINAL SURGERY?" En XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643595.

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Current evidence suggests that peri-operative low-dose heparin administration reduces the post-operative frequency of fatal pulmonary embolism and may also reduce the frequency of fatal myocardial infarction. Evidence is now accumulating that anticoagulants affect the course of malignant disease, in particular the formation of metastases. Malignant cells disseminated during surgery may be responsible for metastasis formation.The aim of this study was to discover whether administration of peri-operative low-dose heparin had any effect on mortality. A retrospective analysis of 1,232 patients undergoing elective abdominal surgery was performed. 658 patients received no heparin and 574 patients received heparin prophylaxis subcutaneously. The two groups were well matched for age, sex, type of operation performed and distribution of pre-existing disease. The number and causes of death are shown below.Low-dose peri-operative heparin administration reduces postoperative mortality. This reduction is only partly explained by a reduction in cardiopulmonary cases, more significantly there Is a reduction in death due to disseminated malignancy.A prospective study is planned in patients undergoing operations for malignancy to confirm this finding.

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Lin, Guanjing y David E. Claridge. "Retrospective Testing of an Automated Building Commissioning Analysis Tool (ABCAT)". En ASME 2009 3rd International Conference on Energy Sustainability collocated with the Heat Transfer and InterPACK09 Conferences. ASMEDC, 2009. http://dx.doi.org/10.1115/es2009-90040.

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Commissioning services have proven successful in reducing building energy consumption, but the optimal energy performance obtained by commissioning may subsequently degrade. Automated Building Commissioning Analysis Tool (ABCAT), which combines a calibrated simulation with diagnostic techniques, is a simple and cost efficient tool that can help maintain the optimal building energy performance after building commissioning. It can continuously monitor whole building energy consumption, warn operation personnel when an HVAC system problem has increased energy consumption, and assist them in identifying the possible cause(s) of the problem. This paper presents the results of a retrospective implementation of ABCAT on five buildings, each of which has at least three years of post-commissioning daily energy consumption data, on the Texas A&M University campus. The methodology of ABCAT is reviewed and the implementation process of ABCAT on one building is specifically illustrated. Eighteen faults were detected in 15 building-years of consumption data with a defined fault detection standard. The causes of some of the detected faults are verified with historical documentation. The remaining fault diagnoses remain unconfirmed due to data quality issues and incomplete information on maintenance performed in the buildings.

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Vantsevich, Vladimir V., Bhargav H. Joshi y Gianantonio Bortolin. "Transmission Gear Ratio vs Fuel Consumption: Retrospective Analysis for Future Terrain Vehicle Applications". En ASME 2012 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/detc2012-70478.

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For decades, the technical problem of selecting optimal transmission gear ratio has been researched for various ground vehicles based on different selection criteria depending on a particular vehicle application; criteria of terrain mobility, traction and acceleration performance, engine power utilization and fuel efficiency have been widely in use. Innumerable analytical and experimental research results and data were implemented in thousand different transmission designs. Today, this unique information about the number of gears in transmission, and value of gear ratios make a field for (i) a research analysis of engineering efficiency of different transmission designs, which were in operation for decades, and (ii) developing more efficient analytical methodologies to select the number of gears and transmission gear ratios and, furthermore, continuously, in-real time control power transfer from the vehicle energy source to the wheels. This paper considers the first, of the above-listed problems in detail with applications to various terrain vehicles and then specifically to off-road wheeled vehicles. The analysis presented in the paper, envelops simple random samples of up to 50 vehicles. It starts from WW2 military vehicles, goes to off-road trucks of 1980s and finally compares modern dump trucks and other terrain vehicles of several major world OEMs. The paper presents an analytical method, computational algorithm and results of a study in which, the efficiency of conventional analytical methodologies are evaluated using actual data on fuel consumption and characteristics of transmissions, vehicle engines, driveline and running gear systems and payloads. To serve this purpose, actual data of each vehicle is compared with analytical data of the vehicle, computed using the conventional methods, with focus on gear/velocity ratios and average fuel consumption at each transmission gear. The fuel consumption analysis was carried out by computing vehicle transport capacity as a function of the average velocity and mass of the payload for each vehicle. The result shows a distinct change of behavior in gear design methodology between post war and present day vehicles. It was a determined divergence from the initial trends, which were based on either the geometrical progression method or arithmetic method for selecting the number of transmission speeds and the values of gear ratios. This resulted in not only having a wide range of speed characteristics of automatic transmission over a few manual gears, but also, as discovered in this study, lead to increased fuel consumption of some vehicles in all range of speeds. The WW2 vehicles designed with manual transmission have gear ratios are closely aligned to analytically calculated geometric progression. Same behavior is observed in the off-road vehicles of 1980’s. Here, with a manual transmission, the trend is more towards less number of gears and with large interval between speed ratios. This of course gives a better fuel efficiency, but leads to trade off in lower average vehicle velocity. The transmission design for modern day dump trucks is also very close to the geometric progression approach. The other modern off-road trucks, as discovered in the analysis, follow an arithmetic progression. Although this results in smooth transmission, but fuel efficiency is compromised significantly, compared to dump trucks. It is important to note that a design based on geometric progression, would result in same speed distribution with less number of gears and better fuel efficiency. For a modern day terrain trucks, to have an optimum combination of both characteristics, it is important to consider all the parameters affecting velocity ratios and fuel consumption and incorporate an efficient analytical methodology to stay competitive, in the rapidly evolving market of all terrain vehicles.

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Informes sobre el tema "Retrospective operation"

Acred, Aleksander, Milena Devineni y Lindsey Blake. Opioid Free Anesthesia to Prevent Post Operative Nausea/Vomiting. University of Tennessee Health Science Center, julio de 2021. http://dx.doi.org/10.21007/con.dnp.2021.0006.

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Purpose The purpose of this study is to compare the incidence of post-operative nausea and vomiting (PONV) in opioid-utilizing and opioid-free general anesthesia. Background PONV is an extremely common, potentially dangerous side effect of general anesthesia. PONV is caused by a collection of anesthetic and surgical interventions. Current practice to prevent PONV is to use 1-2 antiemetics during surgery, identify high risk patients and utilize tracheal intubation over laryngeal airways when indicated. Current research suggests minimizing the use of volatile anesthetics and opioids can reduce the incidence of PONV, but this does not reflect current practice. Methods In this scoping review, the MeSH search terms used to collect data were “anesthesia”, “postoperative nausea and vomiting”, “morbidity”, “retrospective studies”, “anesthesia, general”, “analgesics, opioid”, “pain postoperative”, “pain management” and “anesthesia, intravenous”. The Discovery Search engine, AccessMedicine and UpToDate were the search engines used to research this data. Filters were applied to these searches to ensure all the literature was peer-reviewed, full-text and preferably from academic journals. Results Opioid free anesthesia was found to decrease PONV by 69%. PONV incidence was overwhelming decreased with opioid free anesthesia in every study that was reviewed. Implications The future direction of opioid-free anesthesia and PONV prevention are broad topics to discuss, due to the nature of anesthesia. Administration of TIVA, esmolol and ketamine, as well as the decision to withhold opioids, are solely up to the anesthesia provider’s discretion. Increasing research and education in the importance of opioid-free anesthesia to decrease the incidence of PONV will be necessary to ensure anesthesia providers choose this protocol in their practice.

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