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31.
Islet transplantation is becoming an accepted therapy to cure type I diabetes mellitus. The exact mechanisms of islet allograft rejection remain unclear, however. In vivo CD4(+) and CD8(+) T cell-depleting strategies and genetically altered mice that did not express MHC class I or class II antigens were used to study the allorecognition and effector pathways of islet allograft rejection in different strains of mice, including autoimmunity-prone nonobese diabetic (NOD) mice. In BALB/c mice, islet rejection depended on both CD4(+) and CD8(+) T cells. In C57BL/6 mice, CD8(+) T cells could eventually mediate islet rejection by themselves, but they produced rejection more efficiently with help from CD4(+) T cells stimulated through either the direct or indirect pathway. In C57BL/6 mice, CD4(+) T cells alone caused islet rejection when only the direct pathway was available but not when only the indirect pathway was available. In contrast, in NOD mice, CD4(+) T cells alone, with only the indirect pathway, could mediate islet and cardiac allograft rejection. These findings indicate that different mouse strains can make use of different pathways for T cell-mediated rejection of islet allografts. In addition, they demonstrate that NOD mice, which develop autoimmunity and are known to be resistant to tolerance induction, have an unusually powerful CD4(+) cell indirect mechanism that can cause rejection of both islet and cardiac allografts. These data shed light on the mechanisms of islet allograft rejection in different responder strains, including those with autoimmunity.  相似文献   
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Thirty-eight patients with mammary gland tuberculosis were evaluated over a 5-year period presenting to the surgical unit of our institution. Unilateral involvement of the breast in a woman presenting at an average age of 29 years was the commonest observation. A lump in the breast with or without discharging sinuses was the most common clinical presentation. Ten (26%) of these patients had breast pain with or without increased breast nodularity. Axillary lymph nodal involvement was evident in 14 (36%) of our patients. Only five patients had associated pulmonary tuberculosis, the rest having an isolated involvement of the breast. Fine-needle aspiration cytology was the most reliable diagnostic modality. Medical therapy with antitubercular drugs ranging from 6 to 9 months was the mainstay of treatment. Surgical intervention was reserved for selected refractory cases.  相似文献   
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Objective: To adapt the Spinal Cord Injury Spasticity Evaluation Tool (SCI-SET) into the Persian language (SCI-SETp) and to examine the reliability and validity of the SCI-SETp in patients with spinal cord injury (SCI).

Design: A cross-sectional and prospective cohort validation study.

Setting: University Neurological Physiotherapy Clinic.

Participants: Adult patients with SCI.

Main Outcome Measures: SCI-SET.

Results: There was no missing data. No floor or ceiling effect was observed. Cronbach's α coefficient was 0.862. Factor analysis suggested 1 factor structure (Eigenvalue?=?8.49) explained 24.27% of the total variance. The ICCagreement for test-retest reliability was 0.84. The standard error of measurement and the smallest detectable change was 0.30 and 0.82, respectively. The divergent relationships demonstrated the SCI-SETp uniqueness construct.

Conclusion: The results support the reliability and validity of the SCI-SETp for assessing the impact of spasticity on daily life of patients with SCI.  相似文献   
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To assess the risk for venous thrombo-embolism (VTE) and the utilisation of VTE prophylaxis in an open medical-surgical intensive care unit (ICU), patients were admitted and enrolled to the ICU at a multispecialty, tertiary care teaching hospital in Mumbai, for an observational study during a 3-month period. Risk factors for VTE and methods of VTE prophylaxis used were noted. Risk stratification was done, and the consultants attending the ICUs filled a questionnaire about VTE awareness, preferences and usage of VTE prophylaxis methods and reasons for not using thromboprophylaxis. Of 580 admissions, 488 were included in the study. As per the risk stratification, thromboprophylaxis was indicated in 466 (95%). The study group had an average VTE risk of 5.74, with a mean risk of 6.48 in medical patients and 5.0 in surgical patients. The most common risk factors in medical patients were bed rest >72 hours (56%), age >60 years (49.6%) and age 40-60 years (38.4%). Among surgical patients, the most common risk factors were major surgery (80.25%), central venous access (59.24%) and age 40-60 years (46.6%). Overall, VTE prophylaxis was used in 229 patients (47%), with 127 (55%) medical and 102 (45%) surgical patients. The most common methods of VTE prophylaxis used were elastic stockings (24.2%), low molecular weight heparin (15%) and low molecular weight heparin and stockings both (9.6%). Fear of bleeding was the commonest reason cited for the underutilisation of VTE prophylaxis. Almost half of all high-risk patients admitted to the ICU didn't receive any thromboprophylaxis. Consistent practice patterns of ICUs, and continuing medical education programmes addressing VTE prophylaxis will help improve the usage of VTE prophylaxis.  相似文献   
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卢涛  高天文  刘玉峰  李春英  孙林潮 《医学争鸣》2001,22(12):1147-1147
0 引言 白癜风患者免疫紊乱 ,黑素细胞 (melanocyte,MC)异体移植有可能不被排斥 ,治疗如成功将有很大临床前景 [1 ] .探索同种异体黑素细胞移植后的效果很有意义 .1 病例报告 女 ,2 7岁 ,确诊白癜风 (稳定期 ) ,患者皮肤自幼出现色素脱失斑 ,逐渐增多扩大 . 1996年外用“敏白灵”,前2 mo有效 . 1999- 0 7外用补骨酯酊 ,日服 5 g· L- 1 硫酸铜 10m L和中药 1剂 ,转移因子 4m L ,sc,1· 2 d- 1 .皮损缩小 ,4mo后稳定 .用健康男青年环切的包皮培养 MC,第 4代大约80 %融合时 ,用 2 .5 g· L- 1 胰酶消化 5 min,加入含 2 0 0 g·L- 1小…  相似文献   
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Aims and Objectives: To assess the accuracy of ultrasonography in the diagnosis of acute appendicitis. Methodology: A prospective randomized study was carried in the Dept. of Radiology and Imaging, Tribhuvan University, Teaching Hospital, Maharajgunj, Kathmandu, Nepal. A total of 120 patients, who were clinically diagnosed as acute appendicitis were subjected to ultrasonography of the abdomen. A detailed ultrasonography was performed and the findings were recorded. Twenty one cases had alternate diagnosis. Ninety nine cases ultimately underwent laparotomy and the retrieved appendices were sent for histopathological examination. Intra-operative, histopathological and ultrasonographic diagnoses were then statistically analyzed. Results: Ultrasonographic, intra-operative and histopathological findings were statistically insignificant (P0.05). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy percentage of ultrasonography in the diagnosis of acute appendicitis was 85.7%, 100%, 100%, 6.7% and 85.9% respectively. Conclusion: Ultrasonography has a high degree of accuracy in the diagnosis of acute appendicitis. However, the diagnosis should be considered with the diameter of appendix over 6 mm. Therefore acute appendicitis with diameter of appendix having less than 6 mm should be evaluated with other diagnostic parameters. Key words: Acute Appendicitis, Ultrasonography.  相似文献   
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Methodology for the computer analysis of 201T1 myocardial perfusion images has been developed by several laboratories. Substantial evidence of the advantage of this approach over visual inspection alone has been reported. The currently available computer analyses use different algorithms to analyze 201T1 kinetics in the myocardium. The authors evaluated and compared two widely used software programs, Medical Data System (MDS): a mean-count profile, and the Cedars Sinai (CS): a maximal-count profile, of planar 201T1 scintigraphy for their ability to detect coronary artery disease (CAD).  相似文献   
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