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1.
Although prior research has found that homes containing firearms and illicit drug and ethanol users are more likely to be the scene of a homicide than homes that do not contain these elements, the authors studied homicides on the streets as well as in homes so as to assess the role of firearms, cocaine, and ethanol in both settings. Using the files of the Chief Medical Examiner, the authors reviewed all 4,468 homicides occurring in New York City in 1990 and 1991. The most frequent places of occurrence were the streets and other outdoor places (49.6 percent) and the victims'' homes (19.3 percent). Firearms were the cause of death for 49.6 percent of homicides in the home and 80.3 percent of those on the streets. Use of cocaine and ethanol was found more frequently among victims killed on the streets than those killed at home. In addition, victims killed on the streets were more likely to be male, ages 15-24 years, and African American. Further research in regard to prevention and intervention strategies is needed, keeping in mind the different patterns of homicide on the streets compared with those occurring in other settings.  相似文献   
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Macrophages (M?) from pre-diseased autoimmune-prone MRL mice (both MRL/+ and MRL/1pr) dramatically underproduce the cytokine interleukin-1 (IL-1) in comparison to M? from a number of normal strains. In this study we show that IL-1 dysregulation by MRL M? is fully expressed at birth, and that this defect does not change with time or the development of disease. We also constructed adult irradiation chimeras (consisting of A/J → MRL and MRL → A/J mice), and show that M? isolated from these chimeras display a pattern of IL-1 production indistinguishable from that of the donor strain controls. Moreover, when we constructed a mixed chimera (A/J + MRL → A/J), the A/J and MRL M? coexisting within the same animal retained their individual patterns of IL-1 production when isolated by negative selection. Taken together, these results provide the first substantive evidence for an intrinsic defect (IL-1 dysregulation) in M? from MRL autoimmune-prone mice.  相似文献   
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Project DIRECT (Diabetes Interventions Reaching and Educating Communities Together) is the first comprehensive community diabetes demonstration project in the United States in an African-American community. This article describes its intervention components and evaluation design. The development and implementation of Project DIRECT has included the community since the project''s beginning. Interventions are targeted in three areas: health promotion (improving diet and physical activity levels), outreach (improving diabetes awareness, detection of undiagnosed diabetes, and ensuring that persons with diabetes who are not receiving continuing diabetes care are integrated into the health-care system), and diabetes care (improving self-care, increasing access, and improving the quality of diabetes preventive care received within the health-care system). Evaluation will be internal (conducted by Project DIRECT staff to assess process outcomes in persons directly exposed to each specific intervention) and external (review of outcomes to assess the impact of the multi-intervention program at the level of the entire community). Because diabetes exacts a disproportionate toll among African Americans, the findings from this project should aid in developing strategies to lessen the burden of this disorder, particularly among minority populations.  相似文献   
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OBJECTIVES. This study was undertaken to explore smoking patterns and attitudes that influence smoking cessation and relapse among African Americans. METHODS. Baseline data from eight Community Intervention Trial for Smoking Cessation (COMMIT) sites were analyzed. RESULTS. Compared with Whites, African Americans who smoke less than 25 cigarettes per day were 1.6 times more likely to smoke within 10 minutes of awakening (a behavioral indicator of nicotine dependence), adjusting for education, age, and gender (OR = 1.2 for heavier smokers). African Americans reported a stronger desire to quit smoking and reported serious quit attempts in the past year. African Americans favored tobacco restrictions (they were 1.8 times more likely than Whites to view smoking as a serious community problem, 1.7 times more likely to favor restrictions on cigarette vending machines, and 2.1 times more likely to prohibit smoking in their car). African Americans were lighter/moderate, menthol smokers. CONCLUSIONS. African Americans find smoking socially unacceptable and are strongly motivated to quit, but their "wake-up" smoking may indicate high nicotine dependence, making abstinence difficult even for lighter smokers.  相似文献   
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Maxillary first molar with six canals   总被引:3,自引:0,他引:3  
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A human immunodeficiency virus (HIV) as a biological endpoint in HIV prevention trials may not be feasible, so investigators have used surrogate biological outcomes. In a multisite trial, the epidemiology of STIs may be different across sites and preclude using one STI as the outcome. This study explored using a composite STI outcome to address that problem. The combined biological endpoint was the incidence of any of six new STIs (chlamydia, gonorrhea, trichomonas (women only), syphilis, herpes simplex virus type 2 infection and HIV) during a 24-month follow up period. We investigated how a composite STI outcome would perform compared to single and dual STI outcomes under various conditions. We simulated outcomes for four populations that represented a wide range of sex and age distributions, and STI prevalences. The simulations demonstrated that a combined biologic outcome was superior to single and dual STI outcomes in assessing intervention effects in 82 % of the cases. A composite biological outcome was effective in detecting intervention effects and might allow more investigations to incorporate multiple biological outcomes in the assessment of behavioral intervention trials for HIV prevention.  相似文献   
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