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991.
During their first training period in general practice the authors felt that they did not encounter the balanced workload which is the foundation for learning to be a GP. Previous studies confirmed the existence of differences in overall and specific workload between trainees and trainers. From their own experience and from the relevant literature they addressed several factors which might affect the workload of trainees. A study was undertaken to determine differences in workload between trainees and trainers, and to investigate whether certain characteristics of practice and of trainees affect the workload of trainees. Details of surgery consultations with 34 trainee-trainer partnerships were recorded in the north of the Netherlands over 2 weeks. Questionnaires were filled in by trainers, trainees and practice assistants from these 34 general practices. The total number of contacts recorded was 10,103. It was found that trainees see fewer elderly and female patients, less chronic and oncological conditions, but more minor illnesses. They see only 30% of patients with problem behaviour. Factors that influence the trainees' workload, as compared to their trainers' are: list size; selection in the allocation of patients; trainee's experience prior to starting the training stage, and the trainee's sex. Except for problem behaviour, trainees generally see a cross-section of their trainer's practice population. Selection would provide a more balanced workload for trainees.  相似文献   
992.
993.
Sudden cardiac death (SCD) may occur in as many as 40% of all patients who suffer from heart failure. This review describes the scope of the problem, risk factors for SCD, the effect of medications used in heart failure on SCD and the potential effect of the implantable cardioverter-defibrillator in primary prevention.  相似文献   
994.
All-trans retinoic acid (ATRA) has been reported to exert major effects on the immune system, including monocytes/macrophages. The present study was designed to determine whether ATRA would modulate macrophage-associated liver injury induced by Propionibacterium acnes and lipopolysaccharide (LPS) in rats. All-trans retinoic acid administration alleviated the liver injury and reduced the incidence of death following hepatic failure. Serum alanine aminotransferase (ALT) levels 5 h after, and survival rates within 12 h after the administration of LPS were significantly lower in the ATRA-treated group (134 ± 119 IU/L and 72.7%) compared with the control group (713 ± 411 IU/L and 18.2%; P < 0.05). Histological findings supported these results. These effects may be due to suppression of tumour necrosis factor-α (TNF-α) and superoxide anions produced by activated macrophages. Serum levels of TNF-α 1 h after LPS administration were significantly lower in the ATRA-treated group (60.5 ± 7.0 ng/mL) as compared with the control group (105.2 ± 39.3 ng/mL; P < 0.05). Formazan deposition that was generated by the perfusion of the liver with nitroblue tetrazolium, also suggested suppression of the release of superoxide anions from hepatic macrophages. These results suggest that ATRA acts as an immunomodulator in liver injury by suppressing the activation of liver macrophages.  相似文献   
995.
Examination of thyroid function and immune status of children living on the territories polluted by radionuclides in 1993–1994 revealed131I-dependent thyroid autoimmune reactions. These data indicate a possible effect of131I on the pituitary-thyroid and immune systems of children living on the radiation controlled territories. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 8, pp. 216–220, August, 1998  相似文献   
996.
The purpose of this study was to compare the attitudes toward basic sciences of students in a preclinical problem-based curriculum and a conventional lecture-based curriculum at the end of their second year of medical school. The results showed that the PBL class had more positive attitudes toward basic sciences than students in the conventional class. These results may reflect a learning environment where students meet many scientist role models as teachers and where basic science is learnt in the context of clinical problems.  相似文献   
997.
本文对国内19个有关丙型肝炎病毒(HCV)感染与肝细胞癌(HCC)关系的病例对照研究进行Meta分析。经齐性检验表明,19个研究中有17个研究结果是一致的。对此17个研究结果加权合并,累积HCC病例1577例,HCV感染率为23.0%,累积对照1980例,HCV感染率为4.0%;合并OR值为6.7。结果表明,国内HCV感染与HCC关系密切,HCV感染是HCC发生的一个危险因素。  相似文献   
998.
目的:研究内镜Nd:YAG激光治疗食管和贲门早期表浅癌的远期疗效和DNA及p53表达与预后的关系。方法:对内镜激光治疗癌细胞消失的32例食管和贲门早期表浅癌病人进行33~78个月(平均55.3个月)的随访。并与117例早期食管癌和贲门癌的自然病程对比分析。应用ProductLimitEstimate方法计算其存活率。应用免疫组化染色法检测p53表达。应用分光光度计测定癌细胞DNA含量。结果:内镜激光治疗5年存活率为97%,自然病程5年存活率为67%(P<0.01)。p53阳性表达和DNA非整倍体型病人的复发率分别为76.9%和64.3%。结论:内镜Nd:YAG激光是治疗食管和贲门早期表浅癌的有效方法。抗癌基因p53和DNA倍体数与病人的预后有关。  相似文献   
999.
用六亚甲基二乙酰胺(HMBA)作为分化诱导剂,对人粘液表皮样癌细胞系MEC-1细胞中角蛋白进行染色,结果发现高分子量角蛋白在被诱导细胞中含量明显增高。分光光度仪检测角蛋白含量,诱导组x±s为218±51,对照组为149±47,两组有显著差异(P<001),这可能与细胞分化有关。  相似文献   
1000.
江苏省1966-1995年甲乙类传染病的变迁   总被引:4,自引:0,他引:4       下载免费PDF全文
本文全面分析了1966-1995年30年来江苏省甲、乙类传染病发病率、死亡率及其构成谱的变迁,在充分肯定传染病防制工作成就的同时指出传染病尤其是肠道传染病仍应是当前防病工作的重点,并建议在监测点上建立非传染病防治实验区.  相似文献   
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