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901.
INTRODUCTION: This longitudinal study examined the prevalence and demographic correlates of unprotected insertive and receptive anal intercourse among HIV-positive gay and bisexual men who were aware of their serostatus. METHODS: Participants (n = 395), sampled randomly at two HIV outpatient clinics in Los Angeles, completed two waves of self-administered questionnaires (separated by approximately 7-9 months) that measured sexual behaviors in the previous 60 days. RESULTS: The cross-sectional prevalence of unprotected insertive anal intercourse was 11.2% at time 1 and 7.1% at time 2. Longitudinal analysis indicated that nearly 15% of the participants had engaged in that high-risk behavior either at time 1 or time 2 and approximately 4% had engaged in the behavior at each time period. Similar rates of unprotected receptive anal intercourse were observed. These high-risk activities were more prevalent with seropositive and unknown serostatus partners than with seronegative partners. The rate of anal intercourse risk behaviors was higher among asymptomatic men and among those who were exclusively gay. CONCLUSION: The findings demonstrate considerable differences in the prevalence of stable and occasional high-risk sexual behaviors among HIV-positive gay and bisexual men. Simple cross-sectional analyses cannot capture the stability or variation in behavior across time and, thus, may generate misleading conclusions about disease transmission, especially if the partner's HIV serostatus is not considered in the analysis. The findings indicate a need for focused safer-sex interventions for seropositive men. The HIV outpatient clinic is an ideal setting for such interventions.  相似文献   
902.
BACKGROUND: Few data are available regarding the impact of improved depression treatment on daily functioning and disability. METHODS: In two studies of more intensive depression treatment in primary care, patients initiating antidepressant treatment were randomly assigned to either usual care or to a collaborative management programme including patient education, on-site mental health treatment, adjustment of antidepressant medication, behavioural activation and monitoring of medication adherence. Assessments at baseline as well as 4 and 7 months included several measures of impairment, daily functioning and disability: self-rated overall health, number of bodily pains, number of somatization symptoms, changes in work due to health, reduction in leisure activities due to health, number of disability days and number of restricted activity days. RESULTS: Average data from the 4- and 7-month assessments in both studies, intervention patients reported fewer somatic symptoms (OR 0.68, 95% CI 0.46, 0.99) and more favourable overall health (OR 0.50, 95% CI 0.28, 0.91). While intervention patients fared better on other measures of functional impairment and disability, none of these differences reached statistical significance. CONCLUSIONS: More effective acute-phase depression treatment reduced somatic distress and improved self-rated overall health. The absence of a significant intervention effect on other disability measures may reflect the brief treatment and follow-up period and the influence of other individual and environmental factors on disability.  相似文献   
903.
The authors present a rare case of transitory osteonecrosis of the humeral head with anterior instability of the glenohumeral joint, which occurred in a young male aged 19 years, three months after fracturing his clavicle in a fall. Core decompression of the humeral epiphysis and anterior capsulomioplasty according to Symeonides was performed. Five months after surgery the patient was clinically cured. After having excluded the possibility of metabolic imbalance in the patient, we presumed a direct relationship between the trauma and degenerative pathology affecting the humeral epiphysis.  相似文献   
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