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51.
An estimated 38.6 million persons globally are living with HIV, of whom over 1.1 million reside in Zambia. Of the 2 million cases in the US, 64% of new cases among women are among African Americans. Alcohol and drug use represents a significant risk factor for HIV transmission among both Zambians and African Americans. In addition, gender dynamics in both the US and Zambia promote transmission. This study examines two interventions targeting HIV risk behavior among HIV positive substance users, women in Miami, USA (the New Opportunities for Women (NOW) Project) and men in Lusaka, Zambia (the Partner Project). The study compares the efficacy of these two culturally tailored sexual behavior interventions provided in group and individual session formats. US and Zambian participants increased sexual barrier use and reduced substance-related sexual risk. Comparatively greater gains were made by higher risk Zambian males than US females in both group and individual conditions. Among lower risk participants, women in the group condition achieved and sustained the greatest comparative risk reductions. Results suggest that cost effective group HIV transmission risk reduction interventions for multiethnic individuals can be successfully implemented among both female and male drug and alcohol users in multinational settings.  相似文献   
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Experiments were conducted to assess whether changing dietary fat composition altered phospholipid composition of rat testicular plasma membranes in a manner that altered receptor-mediated action of luteinizing hormone (LH)/human chorionic gonadotropin (hCG). Weanling rats were fed diets that provided high or low cholesterol intakes and that were enriched with linseed oil, fish oil or beef tallow for 4 wk. Feeding diets high in (n-3) fatty acids decreased plasma and testicular plasma membrane 20:4(n-6) content. A marked reduction of the 22:5(n-6) content and an increase in the 22:6(n-3) content of testicular plasma membrane was found only in animals fed fish oil. A decrease in binding capacity of the gonadotropin (LH/hCG) receptor in the plasma membrane, with no change in receptor affinity, was observed for animals fed either linseed oil or fish oil diets. Dietary treatments that raised plasma membrane cholesterol content and the cholesterol to phospholipid ratio in the membrane were associated with increased binding capacity of the gonadotropin receptor. Feeding diets high in 18:3(n-3) vs. those high in fish oil altered receptor-mediated adenylate cyclase activity in a manner that depended on the level of dietary cholesterol. Feeding diets high in cholesterol or fish oil increased basal and LH-stimulated testosterone synthesis relative to that in animals fed the low cholesterol diet containing linseed oil. It is concluded that changing the fat composition of the diet alters the phospholipid composition of rat testicular plasma membranes and that this change in composition influences membrane-mediated unmasking of gonadotropin receptor-mediated action in testicular tissue.  相似文献   
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M Garg  S Rubayi  J Z Montgomerie 《Paraplegia》1992,30(10):734-739
Severe pressure ulcers in patients with spinal cord injury are frequently treated by using musculocutaneous (m-c) flap surgery. There have been few studies of the use of perioperative antibiotics to prevent postoperative infection in this setting. We reviewed 74 m-c flap surgeries in 53 patients (41 male and 12 female) from October 1989 for one year. The sites involved were ischial (31), sacral (24), trochanteric (18), deltoid (2), olecranon (1) and posterior thigh (1). An antibiotic was usually administered perioperatively for 5 days. Patients were followed for a median of 30 (8-96) weeks. Postoperative infections occurred at a median of 12 (4-25) days in 6 of 74 (8%) surgeries. The organisms cultured from the 6 infected wounds were: Bacteroides sp. (4), Proteus mirabilis (2), E. coli (2), MRSA (2), and others (6--each isolated once). These results indicate that antibiotics did not prevent postoperative infection in approximately 8% of patients undergoing m-c surgery. The frequency of isolation of Bacteroides sp. from these infections suggests that anaerobic bacteria may persist in healing pressure ulcers and perioperative antibiotics might include coverage for anaerobic bacteria.  相似文献   
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