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91.
BALB/c mice injected at birth with 10(8) semi-allogeneic (C57BL/6 x BALB.IgHb)F1 spleen cells develop a lupus-like syndrome in which autoantibodies bear exclusively the donor allotype. We have analyzed the evolution of donor B cell chimerism and the autoimmune manifestations during the first year of life in these mice. Anti-DNA, -histone, and -cardiolipin IgG antibodies as well as circulating immune complexes appeared in the second week of life, reached the highest values around the sixth week, and then progressively dropped to normal values after the sixth month in most mice. The kinetics of the evolution of the autoimmune manifestations, as well as the kinetics of serum donor Ig allotype, were parallel to the kinetics of donor B cell chimerism, which was particularly prominent in the spleens in early weeks of life, and progressively decreased after remission of the autoimmune syndrome. Membrane-proliferative glomerulonephritis, which was followed as the more representative histological abnormality in this model, was particularly evident after 10 weeks of life, but disappeared by the end of the follow-up. Interestingly, when mice with a self-limited disease were re-injected with 10(8) F1 spleen cells i.v., a flare in the serological manifestations was observed. In these re-injected mice a predominance of anti-DNA, IgG1 antibodies bearing exclusively the donor allotype was also observed, as in the early weeks of life.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
92.
5例新生儿于出生时,生后2小时、4小时、7天起病。表现为紫绀、缺氧发作、呼吸困难及心力衰竭。生后2~7天检查心电图、胸片及超声心动图,分别提供相应的病征。早者于4天、晚者于半月死亡。死后均经病理证实为新生儿严重的紫绀型先天性心血管畸形。本文结合临床与病理资料讨论新生儿紫绀型先天性心脏病特点及血液动力学改变。  相似文献   
93.
We describe the pathological findings in two fatal cases of neonatal infection with herpes simplex virus. One had an encephalitis caused by herpes simplex virus type 2 (HSV-2); the other had a disseminated infection with herpes simplex virus type 1 (HSV-1). Confirmation of the diagnosis was obtained by use of the polymerase chain reaction to amplify viral DNA from paraffin sections of autopsy tissues. By using primers which amplify fragments of the HSV-1 thymidine kinase gene and HSV-2 glycoprotein gene respectively it was possible to discriminate between infection with HSV-1 and HSV-2. In contrast, immunohistochemistry and in situ hybridization using commercially available reagents did not distinguish between HSV-1 and HSV-2 infection. However, immunohistochemistry and in situ hybridization are probably more reliable than the polymerase chain reaction for assessment of the distribution of virus in different tissues.  相似文献   
94.
40岁以上高龄妊娠与分娩结局分析(附56例临床报告)   总被引:2,自引:0,他引:2  
目的 探讨40岁以上妊娠妇女对分娩的影响.方法 回顾性分析1995年12月~2005年12月分娩的40岁以上孕妇56例及同期妊娠的18~34岁孕妇100例,后者为对照组.结果 高龄组不孕史、习惯性流产和子宫肌瘤发生率高于对照组(P<0.01或P<0.0 5);高龄组剖宫产率(78.6%)比对照组(38%)高(P<0.01).但两组的新生儿出生体重、新生儿窒息、新生儿畸形和围生儿死亡率则没有明显差异(P>0.05).结论 40岁以上妇女妊娠的并发症及剖宫产率增高,但只要重视和加强管理,积极预防和治疗合并症,母儿预后较好.  相似文献   
95.
1341名医学生心理健康水平调查分析   总被引:5,自引:0,他引:5  
目的 了解医学生心理健康状况,为今后有针对性地在我校开展心理健康教育及心理咨询活动提供参考依据.方法 按分层整群抽样的方法抽取被试,采用大学生人格问卷(UPI)进行比较.结果 57.94%的学生存在不同程度的心理健康问题.男生心理健康状况优于女生,男、女生之间差异有统计学意义(p<0.01).2004级学生与2005级学生UPI总分比较,两者差异无统计学意义.结论 医学生心理问题不容忽视.应结合医学生的自身特点和性别心理差异,进行不同的心理健康教育.  相似文献   
96.
The most advantageous combination of immunosuppressive agents for cardiac transplant recipients has not yet been established. Between November 2001 and June 2003, 343 de novo cardiac transplant recipients were randomized to receive steroids and either tacrolimus (TAC) + sirolimus (SRL), TAC + mycophenolate mofetil (MMF) or cyclosporine (CYA) + MMF. Antilymphocyte induction therapy was allowed for up to 5 days. The primary endpoint of >/=3A rejection or hemodynamic compromise rejection requiring treatment showed no significant difference at 6 months (TAC/MMF 22.4%, TAC/SRL 24.3%, CYA/MMF 31.6%, p = 0.271) and 1 year (p = 0.056), but it was significantly lower in the TAC/MMF group when compared only to the CYA/MMF group at 1 year (23.4% vs. 36.8%; p = 0.029). Differences in the incidence of any treated rejection were significant (TAC/SRL = 35%, TAC/MMF = 42%, CYA/MMF = 59%; p < 0.001), as were median levels of serum creatinine (TAC/SRL = 1.5 mg/dL, TAC/MMF = 1.3 mg/dL, CYA/MMF = 1.5 mg/dL; p = 0.032) and triglycerides (TAC/SRL = 162 mg/dL, TAC/MMF = 126 mg/dL, CYA/MMF = 154 mg/dL; p = 0.028). The TAC/SRL group encountered fewer viral infections but more fungal infections and impaired wound healing. These secondary endpoints suggest that the TAC/MMF combination appears to offer more advantages than TAC/SRL or CYA/MMF in cardiac transplant patients, including fewer >/=3A rejections or hemodynamic compromise rejections and an improved side-effect profile.  相似文献   
97.
ABSTRACT: Background: The percentage of United States’ births delivered by cesarean section has increased rapidly in recent years, even for women considered to be at low risk for a cesarean section. The purpose of this paper is to examine infant and neonatal mortality risks associated with primary cesarean section compared with vaginal delivery for singleton full‐term (37–41 weeks’ gestation) women with no indicated medical risks or complications. Methods: National linked birth and infant death data for the 1998–2001 birth cohorts (5,762,037 live births and 11,897 infant deaths) were analyzed to assess the risk of infant and neonatal mortality for women with no indicated risk by method of delivery and cause of death. Multivariable logistic regression was used to model neonatal survival probabilities as a function of delivery method, and sociodemographic and medical risk factors. Results: Neonatal mortality rates were higher among infants delivered by cesarean section (1.77 per 1,000 live births) than for those delivered vaginally (0.62). The magnitude of this difference was reduced only moderately on statistical adjustment for demographic and medical factors, and when deaths due to congenital malformations and events with Apgar scores less than 4 were excluded. The cesarean/vaginal mortality differential was widespread, and not confined to a few causes of death. Conclusions: Understanding the causes of these differentials is important, given the rapid growth in the number of primary cesareans without a reported medical indication. (BIRTH 33:3 September 2006)  相似文献   
98.
Objective To assess the impact of the positional relationship between the large craniopharyngiomas and the third ventricle on the outcome of surgical resection of the tumors. Methods In 72 cases of craniopharyngiomas, the tumors were classified into two types according to the radiographic and surgical findings defining the relationship between the tumors and the third ventricle. For each type of tumors, 3 grades were classified based on the tumor size, texture, and infiltration pattern of the third ventricle. The extend of tumor removal was confirmed by both intraoperative evaluation and postoperative CT or magnetic resonance imaging. The correlation between the degree of hypothalamus invasion and the extend of tumor removal was analyzed in all the cases. Results The craniopharyngiomas were classified into two types, namely those residing in the third ventricle (7 cases) and those invading the third ventricle(65 cases). The degree of tumor resection was significantly different between the 3 grades: total tumor removal was achieved in 95.7% of grade Ⅰ cases, in 80.0% of grade Ⅱ cases, and in only 47.4% of grade Ⅲ I cases (P<0.05). conclusion Understanding of the anatomical relationship of the tumor to the third ventricular floor can be great value for improving the outcome of surgical resection of large craniopharyngiomas.  相似文献   
99.
100.
Abstract Background: Aged Care Assessment Teams (ACATs) have been established throughout Australia during the past seven years. Early studies of their effect have concentrated on their impact on the rate of institutionalisation of disabled elderly, the clinical characteristics of referred cases and the relationship between disability and recommended care plan. Aims: The aim of this study was to explore the relationship between age, clinical features and social characteristics of AC AT subjects with outcomes at 12 months after assessment. Methods: The examination of an arbitrary sample of persons referred to ACATs over a year by one generalist geriatrician with follow-up of all cases by the three ACATs associated with the study was carried out. All analyses were performed on raw data presented as categorical variables in the form of contingency tables. Results: The sample included 324 subjects who suffered from 2030 clinical problems with a mean of 6.5 per person aged 75 or over and 5.5 for those under 75. Cardiovascular and neurological disease were the commonest source of problems. Study of accommodation outcome at 12 months, for those subjects who survived this period revealed that, in the older group, over 60% of subjects with neurological disease were resident in nursing homes while the majority of all other groups remained in the community, as did two-thirds of those aged under 75. Admission to a nursing home was independent of social support for older subjects with neurological disease, but it played a significant role in those with cardiopulmonary or musculoskeletal disease. Conclusions: The study demonstrates that for one-year survivors there is an increased likelihood of admission to a nursing home of people aged 75 or over with neurological disease, while those under 75 were more likely to remain at home. The association was independent of whether spouse, family or friends were living with the subject. (Aust NZ J Med 1994; 24: 378–385.)  相似文献   
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