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991.
992.
HIV-1 infectivity of human carcinoma cell lines lacking CD4 receptors.   总被引:2,自引:0,他引:2  
Human immunodeficiency virus type 1 (HIV-1) prototype, HIV1 LAV, and a Zairian virus HIV1 NDK, an isolate highly cytopathic for CD4+ lymphocytes, were used to infect eleven different CD4 negative non-lymphoid human cell lines. Eight of the lines were derived from carcinomas wherein human papillomavirus was thought to have been etiologic. All these cell lines lacked CD4 receptor and CD4 specific mRNA. After cocultivation with sensitive CEM cells, HIV-1 LAV was rescued from six infected cell lines and HIV-1 NDK from nine. Shedding of free virus into the culture medium was observed in three cell lines infected by HIV-1 NDK and in only one cell line infected by HIV-1 LAV. The infectibility of CD4 negative cell lines indicates that both HIV-1 strains were able to use a CD4 independent mechanism to infect the cells; however, HIV-1 NDK showed the higher efficiency of infection. This virus was also able to overcome the intracellular block of viral reproduction. These results suggest that a broader spectrum of cell types of non-lymphoid origin lacking the CD4 receptor can serve as a viral reservoir. In some cases they are direct producers of infectious HIV-1 particles. This suggests, that in addition to immunosuppressive mechanisms, HIV-1 could play a more direct role in induction of neoplastic changes.  相似文献   
993.
The relationship between dietary fat intake and fasting plasma lipid levels was assessed in 35 female and 19 male adolescents recruited from two local education authority schools in Norwich, UK. Dietary intakes were assessed using a 7-day weighed dietary record method, coupled with the collection of duplicate diets. Fat and energy intakes calculated using food composition tables were compared with values obtained by direct analysis of duplicate diets. Fasting plasma lipid levels (total, HDL and LDL cholesterol and triglycerides) were measured and compared with total dietary lipids and fatty acid intakes. The average proportion of energy consumed as fat was higher than is currently considered desirable but lower than previous studies have reported for adults. Mean serum total cholesterol values were 4.2 (SEM 0.1) mmol for females and 4.5 (SEM 0.2) mmol for males; this difference was not statistically significant. In male subjects the dietary fatty acid profiles were significantly correlated with several parameters of plasma lipid status which are thought to be risk factors for coronary heart disease, and in particular with the ratio of total:HDL cholesterol.  相似文献   
994.
Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 26, No. 5, pp. 43–45, May, 1992.  相似文献   
995.
Ten adult humans were vaccinated with the Japanese acellular pertussis vaccine JNIH-3, containing detoxified pertussis toxin (PT), formaldehyde, and filamentous hemagglutinin. The vaccination induced a specific antibody response to PT and filamentous hemagglutinin, and a Western blot (immunoblot) analysis of the antibody response to PT revealed antibodies to PT subunits S1, S2, S3, S4 and S5. The response of peripheral lymphocytes to PT was assessed in an in vitro proliferation assay. A proliferative response to detoxified PT and PT dimers S2-S4 and S3-S4 was found, and it was further demonstrated that the proliferative response to detoxified PT and dimer S2-S4 was mediated by T cells of the CD4+ phenotype. The specificity of the proliferative response to subunit S4 was analyzed with a range of synthetic peptides synthesized on the basis of the primary sequence of subunit S4. The proliferative response to the peptides revealed two major and one minor T-cell epitope located in the NH2-terminal end of subunit S4.  相似文献   
996.
Scientific-Research Center of Biomedical Radioelectronics, Moscow. Translated from Meditsinskaya Tekhnika, No. 6, pp. 36–37, November–December, 1992.  相似文献   
997.
998.
What is clusterin?   总被引:1,自引:1,他引:0       下载免费PDF全文
  相似文献   
999.
Ten patients with osteosarcomas and rotation plasties made themselves available for a psychological survey. The time elapsed after their operations was between two and ten years, giving an average of six years. All patients were free of tumours at the time of the follow-up examination. Both in personal interviews and in psychological tests, it was possible to observe a very positive development of these patients' attitudes. Contributory factors in this context were discussions with the doctors administering treatment, the cheerful atmosphere of the hospital and the nursing staff, the physicotherapists and ergotherapists, and the excellent social support which all those interviewed also received from their relatives. Continuous positive motivation, a favourable social dialogue and patients' ability to control their own lives would appear to be the key factors in helping patients to come to terms with their illness.  相似文献   
1000.
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