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21.
In contrast to primary gastric lymphomas of B-cell type, little is known about primary gastric T-cell lymphomas. We describe three cases with remarkably similar features: diffuse growth, epitheliotropism, medium too large cell size, high apoptotic rates, and a CD3+, CD4+, CD8+, CD45RO+ immunophenotype. Clonal TCRγ gene rearrangement was shown in two cases. Epstein-Barr virus infection was excluded in two cases. Taking advantage of fresh-frozen material, we analyzed two cases further, revealing CD5–, CD16+, CD56–, CD57–, CD25+, CD30+, CD103 (αEβ7)+, bcl-2 protein+, CD95+, CD95 ligand(L)–. CD95L, however, was detected in histiocytic and fibroblastoid by stander cells. The lymphomas expressed granzyme B, perforin, and the TIA-1 antigen in various combinations. All three cases had a very unfavorable clinical course characterized by local recurrence and/or dissemination to other epithelial sites, leading to death within 6–12 months after the initial diagnosis despite surgery and aggressive antineoplastic treatment. These data suggest a novel variant of peripheral T-cell lymphoma operationally characterized as primary gastric, apoptosis-rich, CD103+, EBV-, T-cell lymphoma co-expressing CD4, CD8, CD16 and cytotoxic molecules. Received: 20 August 1999 / Accepted: 2 November 1999  相似文献   
22.
人体寄生虫学网络课程的应用与评价   总被引:1,自引:0,他引:1  
目的对郧阳医学院人体寄生虫学网络课程的教学效果进行评价。方法选取2005级临床医学一系和二系分别作为实验组和对照组,对照组的人体寄生虫学采用传统教学方法教学,实验组采用传统教学和本课题组构建的人体寄生虫学网络课程平台进行辅助教学。结果实验组学生的人体寄生虫学理论课程考试成绩和实验课程考试成绩明显优于对照组学生(P〈0.05)。结论人体寄生虫学网络课程能够显著提高教学效果,对突破传统面授教学的局限性和帮助学生网上学习具有重要意义。  相似文献   
23.
Summary The clinical courses of 214 patients with infective endocarditis treated between 1958 and 1987 at the First Medical Hospital of the University of Kiel (FRG) were analyzed retrospectively. A decrease in the incidence of endocarditis occurred during the 30-year observation period. The mean age of patients was 48 years, and men were more frequently affected than women. In the course of the investigation, a rise in isolated aortic valve disease was noted, whereas the number of patients with isolated involvement of the mitral valve and combined mitral-aortic valvular defects declined. Streptococci (57%) were the most frequent pathogens isolated; as opposed to their increase, the percentages ofStaphylococcus aureus and enterococci decreased. Otolaryngological, dentogenic and urogenital diseases were most frequently held to be responsible for the development of infective endocarditis. Prior cardiosurgical interventions became increasingly significant as a cause of the disease. In this connection, a rising percentage of endocarditis cases was linked with prosthetically replaced heart valves. Complications and concomitant symptoms of endocarditis included the development of heart failure, cerebral embolism and encephalitis, splenomegaly, and renal inflammation. Finally, the marked decrease in mortality contrasted with a simultaneous rise in the number of endocarditis cases achieving full recovery.  相似文献   
24.
 目的 探讨miR-216a-5p在高迁移率蛋白B1(HMGB1)介导的表皮葡萄球菌感染致小鼠腹膜透析相关腹膜炎(PDAP)中的作用及机制。方法 选取健康雄性C57BL/6J小鼠,随机分为对照组、感染组、感染+HMGB1抑制剂组,收集腹腔积液及腹膜组织分别进行白细胞计数、HE和免疫组织染色;Real-time PCR和Western Blot检测白细胞介素-1α(IL-1α)、白细胞介素-6(IL-6)、肿瘤坏死因素-α(TNF-α)、HMGB1、核转录因子-κB (NF-κB)和核转录因子抑制蛋白(I-κB)的mRNA和蛋白表达水平;生信预测发现,miR-216a-5p可能与HMGB1结合,参与其诱导的PDAP的发生,并构建感染+miR-216a-5p mimics组小鼠,通过双荧光素酶报告基因检测验证miR-216a-5p和HMGB1的关系,采用Real-time PCR、Western Blot、免疫组织染色检测HMGB1的表达变化。结果 与对照组相比,感染组小鼠腹腔积液白细胞计数增多,炎性浸润明显,IL-1α、IL-6、TNF-α,以及HMGB1 mRNA和蛋白表达均升高(均P<0.05);HMGB1抑制剂(甘草素)干预后,小鼠腹腔积液白细胞计数下降,炎性浸润改善,IL-1α、IL-6、TNF-α,以及HMGB1 mRNA和蛋白表达均下降(均P<0.05)。感染组小鼠NF-κB表达高于对照组,I-κB表达低于对照组;HMGB1抑制剂干预后NF-κB表达降低,I-κB表达升高(均P<0.05)。Real-time PCR结果证实,与对照组相比,miR-216a-5p的含量在感染组中显著减少;双荧光素酶报告基因检测提示,miR-216a-5p可直接作用于HMGB1的3’UTR区;与感染组相比,感染+miR-216a-5p mimics组小鼠中HMGB1 mRNA和蛋白表达均下降(均P<0.05)。结论 HMGB1在表皮葡萄球菌感染致小鼠PDAP中发挥重要作用,抑制HMGB1可改善小鼠炎症反应,miR-216a-5p可通过靶向HMGB1参与表皮葡萄球菌感染致PDAP的发生。  相似文献   
25.
PurposeAdolescent parenthood is a major challenge in low- and middle-income countries (LMICs). However, the vast majority of the evidence has focused on adolescent motherhood. Little is known about adolescent fatherhood in LMICs. The aim of this study was to examine the determinants of early fatherhood and its consequences on a range of outcomes among adolescent males.MethodsThis study used three waves of longitudinal data from the multicountry Young Lives cohort study, specifically following a sample of 1,779 adolescent boys at ages 15, 19, and 22 years in Ethiopia, India, Peru, and Vietnam. Individual fixed effects models were conducted to investigate the sociodemographic determinants of adolescent fatherhood and the consequences of adolescent fatherhood on males' education, health, psychosocial well-being, and time use outcomes.ResultsThe results indicated that lower educational attainment, absence of the adolescent's mother and father from the home, larger household size, and poverty increased the likelihood of becoming an adolescent father by age 22 years. The results revealed that becoming an adolescent father was associated with a higher likelihood of school dropout, being overweight, smoking, greater internalizing problems, and less time spent on leisure activities and more time spent on caregiving responsibilities.ConclusionsHighlighting the experiences of young men as adolescent parents in LMICs, findings underscore the importance of prevention strategies to delay early parenthood for adolescent boys and multicomponent interventions to support young fathers and their unique health, socioeconomic, psychosocial, and behavioral needs.  相似文献   
26.
 目的 调查医院感染预防与控制课程设计中医学生的教育需求及教师的课程设计建议。方法 采用问卷调查全国5个地区10所医学院校师生的医院感染预防与控制教育需求和课程设计意见,参考塔巴目标模式课程设计步骤,论证课程设计方案。结果 584名学生中,仅11.8%(69名)的学生认为当前医院感染预防与控制教育能完全满足其需求,需求得分居前四位的为手卫生、消毒灭菌隔离、医院感染概论和职业防护。352名教师中,72.7%(256名)建议设必修课;86.4%(304名)选择总学时8~24学时,12.5%(44名)选择24学时以上,被调查教师建议10个章节学时平均总和为19.5;需重点掌握13项、熟悉9项知识和技能;86.4%(304名)教师建议理论与见习学时比为1 ∶0.5及以上;53.4%(188名)教师建议采取理论大课+小组见习(含技能操作)+线上学习的形式;63.7%(224名)教师建议师资团队由医院感染管理科+感染病科+护理部教师共同组成。结论 当前医学生的医院感染预防与控制教育远未完全满足需求,单独开课很有必要,建议设置16~24学时必修课,理论联系实践,多学科师资实施多元化教学,按照必修课考核。  相似文献   
27.
为了提高进修医师的教学质量和医疗水平,我们在2006届进修医师教学工作中加强和细化了进修医师接诊前的培训,取得了良好的效果.实践证明,实施接诊前培训对于提高进修医师的医疗水平和自信心,实施规范化操作,克服诊疗中的盲目性,减少或避免医疗纠纷,进而提高进修医师的教学质量具有重要意义,值得推广和借签.  相似文献   
28.
Summary One hundred and six affective (76 unipolar and 30 bipolar) and 101 schizoaffective patients (45 unipolar and 56 bipolar) were investigated after a long-term course of illness, evaluating sociodemographic and general data, the long-term course of illness, disability and psychosocial alterations according to WHO/DAS, WHO/PIRS and GAS, as well as several social consequences of the illness (living situation at the end of the observation time, downward occupational drift, downward social drift, premature retirement, achievement of the expected social development). Comparing the 30 bipolar affective and 56 bipolar schizoaffective disorders, no differences were found regarding (a) sociodemographic and general data (i.e. sex distribution, age at onset, education and occupation at onset, stable heterosexual relationship, premorbid personality and social interactions, mental illness in the family, broken home, life events, season of birth and social classes) and (b) relevant patterns of the long-term course. Regarding long-term out-come the only difference found concerned the more favourable outcome of the bipolar affective disorders according to WHO/DAS, while using GAS the difference was not statistically significant. No difference was found either between the two bipolar groups in the social consequences of the illness. The combining of both bipolar groups as bipolar diseases is discussed, as well as the use of the terms bipolar disease, affective subtype and bipolar disease, schizoaffective subtype.  相似文献   
29.
Summary In order to evaluate the time course of its effects, dimetindene maleate has been investigated in a histamine provocation model in man. Eight healthy male volunteers were treated i. v. with 4 mg dimetindene maleate or sodium chloride solution in a double blind, cross over study. Intracutaneous histamine injections were given at –1, 2, 5, 14, 17, 20, 23, 26, and 29 h following drug administration and the areas of flares and wheals were measured after 5, 10, 20, and 30 min. There was strong inhibition of the development both of flares and wheals, which was more pronounced for the former. Baseline adjusted areas under the curve differed significantly following drug and placebo treatment. The maximum effect was observed at 2 h.The mean residence time of the inhibitory effect was calculated to be 13 h compared to the mean residence time of dimetindene in blood of 5 h, which indicates a non-linear relationship between blood level and effect.  相似文献   
30.
A method is described for investigating life course influences on health in early old age. The lives of some 300 individuals at present aged 65-75 y have been reconstructed from the archived records of a pre-WWII survey, in which they took part as children, and from lifegrid interviews with the same individuals 60 y later. Despite loss to study at several points those interviewed are shown to be representative of the British population socio-demographically, in comparison with the 1931 and 1991 decennial censuses, and physically, in comparison with the Health Survey for England. Bias is conservative because the most disadvantaged were disproportionately affected by loss to follow-up through death and because non-responders to interview were more disadvantaged as children than the interviewees. Representativeness and conservative bias, it is argued, justify the use of these data for investigating life course influences on health in early old age.  相似文献   
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