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111.
J G Wright R J Tesi D W Massop M L Henry J R Durham R M Ferguson W L Smead 《American journal of surgery》1991,162(2):126-130
Patients with aortic disease and end-stage renal failure who require both aortic reconstruction and renal transplantation (simultaneously or staged) pose a formidable clinical challenge. Traditionally, the performance of either one of these procedures has been viewed as a relative contraindication to the performance of the other. From 1978 to 1989, eight patients were referred to us with the combination of aortic disease and end-stage renal failure. Seven had aneurysmal disease and one had aorto-iliac occlusive disease. Five patients presented with their diseases sequentially and had two sequential operations, with a mean interval of 4 years between procedures. Three patients presented with their diseases simultaneously and underwent simultaneous aortic reconstruction and living related renal transplantation. All patients were followed up for a mean interval of 4.5 years. By life-table analysis, the 5-year renal graft survival was 100%, the primary aortic graft patency was 82%, and the secondary aortic graft patency was 100%. The only death in this series occurred 11 years after aortic reconstruction and 4 months after a renal transplantation and was due to overwhelming cytomegalovirus sepsis. There were no significant differences between the simultaneous and staged groups in terms of operative mortality, postoperative complications, transplant function, or aortic graft patency. From this experience, we conclude that: (1) patients who present simultaneously with aortic disease and end-stage renal failure can safely undergo simultaneous aortic reconstruction and renal transplantation; (2) patients who present with these two diseases sequentially can undergo a second reconstructive procedure with very low operative morbidity and mortality rates; (3) when these two procedures have been performed sequentially, the second procedure has not significantly altered the 30-day or 5-year results of the first procedure; and (4) the 30-day and 5-year results of each procedure have been excellent regardless of the temporal sequence in which they were performed. 相似文献
112.
A photometric study of the effect of pupil dilatation on Nd:YAG laser iridotomy area was performed in 21 eyes of 21 patients. The iridotomy area was 0.075 (0.055) mm-2 (mean (SD)) before pupil dilatation and 0.073 (0.070) mm-2 after pupil dilatation (t test NS). Iridotomy area after pupil dilatation correlated with iridotomy area before pupil dilatation (r = 0.815, p < 0.01) but did not significantly correlate with measures of iridotomy shape or position, or with changed iris area following pupil dilatation. Two iridotomies became reduced to less than 20% of their initial area following pupil dilatation. Our findings suggest that the only effective method of avoiding development of unacceptably small iridotomy area after pupil dilatation is to create a sufficiently large iridotomy at the time of initial laser surgery. 相似文献
113.
114.
Treatment of experimentally induced atherosclerosis in swine iliac arteries: A comparison of self-expanding and balloon-expanded stents 总被引:1,自引:0,他引:1
Chamaree Chuapetcharasopon Kenneth C. Wright Sidney Wallace Richard L. Dobben Cesare Gianturco 《Cardiovascular and interventional radiology》1992,15(3):143-150
Atherosclerosis was induced in 20 Hanford miniature swine. Subsequently, one iliac artery lesion in each of 16 pigs was stented
with either a self-expanding (8 pigs) or a balloon-expanded (8 pigs) stent. Immediately after stent placement, 4 animals in
each group were taken off the atherogenic diet and continued on normal chow for the remainder of the study. Four months after
stents were placed, atherosclerosis and the mural changes associated with the stent were more clearly evident in the arteries
of the pigs continued on the atherogenic diet. These pigs also exhibited significantly more neointimal proliferation. In addition,
the arteries containing the balloon-expanded stents showed more extensive and complex intimal changes when compared with arteries
with self-expanding stents. Although both stent designs were equally effective in maintaining vascular patency, the balloon-expanded
stent was more traumatic to the vessel wall which resulted in a significantly greater neointimal thickness. 相似文献
115.
Leukocyte chemoattraction by 1,2-diacylglycerol. 总被引:3,自引:0,他引:3
T M Wright R D Hoffman J Nishijima L Jakoi R Snyderman H S Shin 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(6):1869-1873
Previous reports have demonstrated the hydrolysis of inositol phospholipids in polymorphonuclear leukocytes (PMN) in response to chemoattractants and in lymphocytes in response to the mitogen phytohemagglutinin. We investigated the role of 1,2-diacylglycerol, one of the products of receptor-linked phosphatidylinositol hydrolysis, in mediating the migratory response of leukocytes. In an under-agarose migration system, we found 1,2-dioctanoylglycerol to be a strong chemoattractant for human PMN, 6C3HED (a mouse thymic lymphoma), and Jurkat (a human T-cell leukemia). By using a modified Boyden chamber assay, the migratory response of PMN to 1,2-dioctanoylglycerol was determined to be primarily chemotactic. Analysis of structural analogs indicated that both the position and number of acyl chains are important in determining chemoattractant activity. These studies demonstrate that exogenous 1,2-diacylglycerol can stimulate the directed migration of leukocytes. They further suggest that the formation of 1,2-diacylglycerol following receptor-mediated stimulation may represent a common step in the migratory responses of myeloid and lymphoid cells. 相似文献
116.
117.
Reliability of radiographic measurement of fracture angulation in children with femoral shaft fractures
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INTRODUCTION: Clinical decisions are based on x-ray measures of radiographs. However, the reliability of assessing the angular measurement of fractured femurs in children is unknown. The purpose of this study was to determine the intra- and interrater reliability of an x-ray assessment of femoral shaft fracture angulation in children. METHODS: On 2 occasions, 3 raters evaluated 30 radiographs of children aged 4 to 10 years, 3 to 24 months after a femoral fracture. The radiographs were evaluated by an orthopedic surgeon, an orthopedic fellow and a research assistant, using a standardized methodology. Reliability was assessed with the intraclass correlation coefficient (ICC), an index of concordance that ranges from 01, where > 0.75 indicates excellent concordance. RESULTS: The ICC for the intrarater ranged from 0.75 to 0.97. The interrater reliability ICC for anterior or posterior angulation was 0.91 (95% confidence interval [CI] 0.840.95) and for varus or valgus angulation was 0.90 (95% CI 0.790.95). A change in measurement of more than 5 degrees exceeds the variation in measurement and, therefore, can be attributed to a true shift in fracture position. CONCLUSIONS: With specific standardized protocols, radiographic assessment of femoral fractures is reliable, irrespective of the examiner's level of experience. 相似文献
118.
J Rymaszewska J Jarosz-Nowak A Kiejna T Kallert M Schützwohl S Priebe D Wright P Nawka J Raboch 《European psychiatry》2007,22(3):160-166
ObjectiveTo assess the social disability of people with different psychiatric disorders.MethodsCross-site survey in five psychiatric hospitals (Dresden, Wrocław, London, Michalovce and Prague). Working-aged patients diagnosed (ICD-10) with schizophrenia and related disorders (F2), affective disorders (F3), anxiety disorders (F4), eating disorders (F5) and personality disorders (F6), were assessed at admission (n = 969) and 3 months after discharge (n = 753) using the Brief Psychiatric Rating Scale and the Groningen Social Disability Schedule. The main outcome measure was Interviewer-rated social disability.ResultsDuring acute episodes patients with personality, eating and schizophrenic disorders functioned less effectively than those with affective or anxiety disorders. After controlling for age and severity of psychopathology, there was no significant effect of the diagnosis (during remission), sex, education and history of disorder on disability. Site, employment and partnership were significant factors for the level of social disability in both measure points.ConclusionSeverity of psychopathological symptoms, not the diagnosis of a mental disorder, was the most significant factor in determining the level of social functioning, particularly during the remission period. Site, employment and partnership appeared as significant factors influencing the level of social disability. 相似文献
119.
Kristin Fraser Adam Peets Ian Walker Janet Tworek Michael Paget Bruce Wright & Kevin McLaughlin 《Medical education》2009,43(8):784-789
Context Prior research has demonstrated that residents have poor clinical skills in cardiology and respirology. It is not clear how these skills can be improved because the number of patients with suitable clinical findings whose cooperation might help residents to better develop these clinical skills is limited.
Objectives Our objective was to evaluate the effect of training on a cardiorespiratory simulator (CRS) on skills acquisition, retention and transfer.
Methods We randomly allocated 146 students to CRS training in either chest pain or dyspnoea and compared each student's performance on the clinical presentation in which he or she had received CRS training with performance on the control presentation.
Results Immediately after training, students were more accurate in identifying abnormal clinical findings on the CRS (70.0% versus 52.2%; d = 7.6, P < 0.0001) and showed improved diagnostic performance (72.1% versus 55.6%; d = 4.3, P = 0.0007) on the training clinical presentation. At the end of the course they were still better at identifying abnormal findings (57.1% versus 51.7%; d = 2.5, P = 0.004) and diagnosing correctly (50.0% versus 38.1%; d = 3.0, P = 0.002) on problems included in the training clinical presentation. However, they showed no difference between training and control presentations in diagnostic performance when required to transfer their skills between problems (45.9% versus 43.8%; P = 0.5) or in performance on multiple-choice questions (64.1% versus 63.6%; P = 0.8).
Conclusions Students can acquire and retain clinical skills with CRS training, but demonstrate limited ability to transfer these to other problems. Further studies are needed to explore ways of improving learning and transfer with CRS training. 相似文献
Objectives Our objective was to evaluate the effect of training on a cardiorespiratory simulator (CRS) on skills acquisition, retention and transfer.
Methods We randomly allocated 146 students to CRS training in either chest pain or dyspnoea and compared each student's performance on the clinical presentation in which he or she had received CRS training with performance on the control presentation.
Results Immediately after training, students were more accurate in identifying abnormal clinical findings on the CRS (70.0% versus 52.2%; d = 7.6, P < 0.0001) and showed improved diagnostic performance (72.1% versus 55.6%; d = 4.3, P = 0.0007) on the training clinical presentation. At the end of the course they were still better at identifying abnormal findings (57.1% versus 51.7%; d = 2.5, P = 0.004) and diagnosing correctly (50.0% versus 38.1%; d = 3.0, P = 0.002) on problems included in the training clinical presentation. However, they showed no difference between training and control presentations in diagnostic performance when required to transfer their skills between problems (45.9% versus 43.8%; P = 0.5) or in performance on multiple-choice questions (64.1% versus 63.6%; P = 0.8).
Conclusions Students can acquire and retain clinical skills with CRS training, but demonstrate limited ability to transfer these to other problems. Further studies are needed to explore ways of improving learning and transfer with CRS training. 相似文献
120.