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991.
Changes in HIV-1 incidence in heroin users in Guangxi Province, China   总被引:10,自引:0,他引:10  
Guangxi Province, China recently experienced an outbreak of HIV-1 infection among heroin users. We studied HIV-1 incidence rates and associated risk factors for HIV-1 infection among heroin users residing in Pingxiang City. A total of 318 heroin users were followed from February 1998 through January 1999 (median follow-up: 8.1 months). Of these, 130 were prospectively followed from January through September 1999 (median follow-up: 8.3 months). HIV-1 and hepatitis C virus (HCV) incidence rates for each period were calculated. A generalized estimating equation approach was implemented to identify independent risk factors associated with HIV-1 infection across both periods. Among 318 study participants, 97.2% were men. The median age was 22 years. Approximately 60% reported sharing needles. HIV-1 prevalence at baseline was 15.4%. During the first follow-up period, HIV-1 incidence was 2.38 per 100 person years (py), and HCV incidence was 26.8 per 100 py. During the second follow-up period, HIV-1 incidence was 6.86 per 100 py, and HCV incidence was 28.9 per 100 py. After controlling for age and other factors, HCV seropositivity, history of sexually transmitted diseases, and sharing needles were independently associated with HIV-1 infection. These data suggest that HIV-1 incidence was rising over time in Pingxiang City, Guangxi Province. The high incidence of HCV heightens the importance of enhanced prevention programs to reduce injection and needle sharing among heroin users.  相似文献   
992.
Department of Biomembranes, Research Center for Development and Introduction of Modern Methods of Molecular Diagnosis, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR I. P. Ashmarin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 109, No. 5, pp. 483–485, May, 1990.  相似文献   
993.
Laboratory of Regulation of Immunopoiesis, Institute of Clinical Immunology, Siberian Branch, Academy of Medical Sciences of the USSR, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 105, No. 3, pp. 311–313, March, 1988.  相似文献   
994.
Reduction in the epididymis weight and in the spermatozoid concentration together with marked morphological changes in the seminiferous tubules were observed in the progeny of irradiated rats. Vitamin E content in the testes increased 2.8-fold, while that of vitamin B2 decreased 1.6-fold. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 12, pp. 652–654, December, 1998.  相似文献   
995.
We report a case of leukemia cutis with atypical skin manifestations, presented with generalized various sized dark brownish to erythematous patches with plaques on the whole body of a 42-year-old man. Skin lesions developed 6 months ago and had no signs of itching or tenderness. He complained of sustaining fevers with abdominal discomfort. Laboratory findings showed elevation of leukocyte count and peripheral blood smear revealed 86% of lymphocyte. Histologic examination showed diffuse infiltration of abnormal cells that appeared to be leukemic in nature.  相似文献   
996.
A sandwich radioimmunometric assay using monoclonal antibodies 6G10 and SV2-61 gamma directed to the extracellular domain of the c-erbB-2 oncogene product was developed and the antigen levels in sera from normal donors and patients with breast carcinoma were determined. The antigen levels in normal donors were uniformly low (9.52 +/- 0.91 ng/ml) and 3.0% (2/66 cases) slightly exceeded the cutoff value (11.4 ng/ml). In patients with breast carcinoma, serum c-erbB-2 protein levels increased and the positivity was as high as 45.7% (16/35 cases) in recurrent cases. Determination of c-erbB-2 protein may be a useful marker for serological diagnosis of breast carcinoma.  相似文献   
997.
C Shih  M Y Yu  L S Li  J W Shih 《Virology》1990,179(2):871-873
The human hepatitis B virus (HBV) produced by a rat hepatoma cell line through transfection with HBV DNA is infectious in the human primate model--chimpanzee. Since hepadnaviruses are known to have an extremely narrow host range, our results support the idea that the host species barrier of HBV infection resides on the penetration/adsorption step rather than any postpenetration intracellular event during the virus life cycle.  相似文献   
998.
目的 研究HIV-1膜蛋白(Env)特定糖基化位点改造对Env免疫原性及功能性假病毒形成能力的影响.方法 采用环形诱变,DpnⅠ筛选的方法对Env进行定点突变,单周期感染试验检测功能性假病毒形成能力,免疫小鼠,利用假病毒中和试验与ELISPOT分别检测突变对中和抗体和T细胞分泌Env特异的IFN-γ的影响.结果 N197Q突变体使Env诱导中和抗体的能力提高而诱导T细胞分泌Env特异的IFN-γ的能力降低,并使Env不能形成功能性假病毒;G2突变体(N624Q,N637Q)诱导的中和抗体能更好地中和假病毒74-2,仉中和假病毒Wt的能力下降,对Env诱导T细胞分泌Env特异的IFN-γ的能力和功能性假病毒形成无明显影响.结论 特定糖基化位点的改造影响假病毒的形成及Env的免疫原性.  相似文献   
999.
白塞氏病相关抗原的重组表达及抗原性初步分析   总被引:1,自引:0,他引:1  
目的:探讨Kinectin的抗原性,为下一步研究Kinectin在白塞氏病中的意义奠定基础。方法:从人Hep2细胞抽提RNA,利用RT—PCR扩增能覆盖Kinectin全长的3个片段,其位置分别相当于氨基酸22—510(kin—5),503-994(kin-M)和920-1346(kin-3)。将扩增的PCR片段克隆到pET42—a( )载体中,诱导表达的融合蛋白用白塞氏病病人血清进行Western blot分析。结果:构建的3个表达Kinectin部分片段载体(pET/kin—5、pET/kin-M和pET/Kin-3)具有正确的阅读框架,DNA测序符合率为99%,能在大肠杆菌中表达相应的肽段。8份阳性血清中,用Western blot分析发现,6份血清与kin-M反应,5份血清与kin-3反应,只有一份血清与kin-5有反应。结论:成功地构建表达覆盖Kinectin全长的3个载体,并初步发现Kinectin的抗原性可能主要位于其中间段和羧基端。  相似文献   
1000.
Functional derangements in the brain during the acute period of ischemic hemispheric stroke (IS) were assessed in terms of the severity of the motor neurological deficit in the acute period of IS and neurophysiological measures of motor evoked potentials (MEP) using transcranial magnetic stimulation (TCMS). A total of 52 patients (23 women, 29 men, mean age 58.5 ± 8.7 years) were studied. Patients were divided into two subgroups: group 1 consisted of 29 patients with good functional outcomes from the acute period; group 2 consisted of 23 patients with poor functional outcomes. The use of TCMS for recording MEP demonstrated increases in the latency of the M response both after stimulation of the projection of the motor area of the cortex of the lesioned hemisphere and after stimulation of the spinal cord. There were increases in the central motor conduction time (CMCT) in the lesioned hemisphere of the brain and a negative correlation was seen between the severity of the neurological defect and CMCT on the one hand (r = –0.65 to –0.78; p < 0.001) and, on the other, the latency of the M response in TCMS of the motor zone of the cortex on the side of the hemispheric stroke (r = –0.65 to –0.79; p < 0.001). The increases in the latency of the M response and CMCT have prognostic significance for early assessment of the outcome of IS.  相似文献   
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