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31.
Hepatitis B surface antigen (HBsAg) and antibody (anti-HBsAg) were determined on 442 asymptomatic heroin users and 246 controls. Of the drug-taking group, 124 used heroin intravenously and 318 nonintravenously (smoking, sniffing). Twenty-three (5.2%) heroin users were HBsAg positive and 118 (26.7%) anti-HBsAg positive, compared to three (1.2%) HBsAg positive and 28 (11.4%) anti-HBsAg positive controls, both statistically significant. HBsAg was positive in eight (6.5%) intravenous heroin users and statistically identical to 15 (4.7%) HBsAg positive nonintravenous users. Positive anti-HBsAg in 55 (44.4%) intravenous heroin users compared to 63 (19.8%) nonintravenous users, however, is statistically significicant.  相似文献   
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Summary. The obstetric histories were examined for 36 women with familial Mediterranean fever (FMF) on long-term colchicine treatment followed for periods ranging between 3 and 12 years. Seven of 28 pregnancies (25%) associated with colchicine therapy ended in miscarriage. Thirteen women (36%) had periods of infertility; these were due to ovulatory dysfunction in six women, to peritoneal adhesions in four and remained unexplained in three women. The rates for miscarriage and infertility are high but are similar to those reported for women with FMF before colchicine therapy was introduced. All 16 infants born to mothers who had taken colchicine during pregnancy were healthy. Currently, we do not advise discontinuation of colchicine before planned pregnancy but recommend amniocentesis for karyotyping and reassurance.  相似文献   
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Fourteen monoclonal antibodies recognizing monomorphic and polymorphic epitopes on class I and class II antigens of the human MHC have been assayed on lymphocytes of a panel of 20–150 BoLA typed bovine animals from 12 different breeds. Some monomorphic antibodies cross-reacted and others did not. Two polymorphic monoclonal antibodies in man recognize a polymorphism in cows that follows allospecificities (BoLA-w3, w9) already described. Immunoprecipitation experiments with monomorphic anti-B2m and anti-HLA-DR monoclonal antibodies have shown that these cross-reactions concern BoLA antigens. They also revealed that Ia-like antigens in cattle present the same two chain features characterized in other species.  相似文献   
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The presence of the BCL-2 protein, a marker for inhibition of programmed cell death, was studied in a series of routinely processed cervical tissues, consisting of normal endocervical ( n =40) and ectocervical epithelium ( n =27), squamous metaplastic epithelium ( n =30), CIN (cervical intraepithelial neoplasia) lesions ( n =32), and cervical carcinomas ( n =13). BCL-2 was strongly expressed in the basal cell compartment of normal ectocervical squamous epithelium and in nearly all reserve cells, while in endocervical columnar cells it was moderately expressed. In immature squamous metaplastic epithelium, BCL-2 expression varied. Half of the cases showed only basal cell staining, while the other half showed staining also in suprabasal layers. BCL-2 could be detected in all premalignant lesions, showing a striking increase in the number of positive cells with increasing severity of CIN, in combination with a mild increase in staining intensity. All adenocarcinomas were positive ( n =5), while five of eight squamous cell carcinomas expressed BCL-2. Based on these results, it is hypothesized that both the larger number of cells staining with BCL-2 in higher grades of CIN and the increase in staining intensity imply an increasing protection of these neoplastic conditions against programmed cell death. This protection facilitates not only continuing proliferation, but also the induction of genetic instability in dysplastic epithelial cells; it may thus reflect the greater capacity of the more severe CIN lesions to evolve into cervical carcinoma.  相似文献   
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Noise is a highly relevant environmental and clinical stressor. Compared to most other experimental stressors, noise is a modest activator of neuroendocrine pathways that mimic the situation in human health where neuroendocrine activation by environmental stressors is often absent or difficult to establish. Little is known about the effects of noise exposure on the immune system. In the present work, the effects of a low-intensity chronic intermittent unpredictable noise regimen on various parameters of immune function was studied. Male wistar rats were exposed to a randomized noise protocol (white noise, 85 dB, 2–20 kHz) for 10 h per day, 15 min per h over a total period of 3 weeks. Control animals were exposed to ambient sound only. Immune function was monitored after 24 h, 7 days, and 21 days of noise exposure. Noise induced several significant changes in immune function in a time-dependent differential pattern involving both immunosuppression and immunoenhancement. After 24 h, serum IgM levels were increased and peripheral phagocytic activity was decreased. Splenic lymphocytic proliferation to mitogens was significantly decreased after 7 days, but slightly elevated after 3 weeks. The activity of splenic NK cells was increased significantly after 24 h and 7 days, but suppressed after 3 weeks. These results show that various parameters of immune function are affected differentially over time in a period of chronic mild noise stress, possibly due to sequential activation of different physiological mechanisms.  相似文献   
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