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Social disruption (SDR) of male mice has been shown to induce a state of functional glucocorticoid (GC) resistance in splenocytes. The present study demonstrated that GC resistance developed following repeated, but not acute exposure to SDR. GC resistance was long-lasting and persisted for at least 10 days after stress. In contrast, SDR did not alter cytokine secretion from peritoneal mononuclear cells treated with corticosterone. These findings suggest that SDR-induced GC resistance may be restricted to specific sites such as the spleen.  相似文献   
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The purpose of this study was to examine the effects that changes in behavioral and psychological symptoms of dementia of persons with Alzheimer's disease have on their caregivers' mental health and physical health. The research design was a prospective, longitudinal follow-up study conducted in a major medical center and in participants' homes. Longitudinal analysis linking change in behavior to caregiver outcomes was based on 64 cases. Care recipients were assessed at the time of diagnosis with the Mini-Mental State Examination (MMSE). To provide information on the care recipient's behaviors, caregivers participated in an interview with the Modified Neuropsychiatric Inventory at diagnosis and at follow-up. Caregivers also completed a battery of established instruments to measure stress appraisal, mental health, and perceptions of their physical health at follow-up. Results showed that increases in problem behaviors among persons living with dementia, along with residence status, were significant predictors of caregivers' mental health and also their physical health. However, these relationships were mediated through stress appraisal. Variables such as MMSE score of the person with dementia, number of years caregiving, relationship status, and education level were not significant predictors of caregivers' health when behavior change was in the model.  相似文献   
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BACKGROUND: Walking is a widely used approach to increase physical activity levels in obese patients. In this paper, we investigate the precision and accuracy of an ankle-worn dual-axis accelerometer (Stepwatch) and investigate its potential application as a predictor of energy expenditure. METHODS: Twenty healthy subjects (10 lean, 10 obese) wore spring-levered (Accusplit), piezoelectric (Omron HF-100), and Stepwatch pedometers. Subjects walked on a treadmill at 1, 2, and 3 mph and in a hallway at 1 and 1.85 mph, during which energy expenditure was measured. RESULTS: The Stepwatch counted 99.7 +/- 0.67% (mean +/- SEM) of the manual counts. In comparison, the Omron pedometer counted 61 +/- 3.3% and the Accusplit counted 26 +/- 2.8% of the manual counts at 1 mph although all pedometers were accurate (> 98% of counts) at 3 mph. In repeated measures, the Stepwatch produced negligible variance (SD = 0.36) over all speed whereas the other pedometers showed a large amount of variance at all speed (SD = 4-13). Stepwatch counts were predictive of walking energy expenditure corrected by weight (r2 > 0.8). CONCLUSION: The counts from the Stepwatch were virtually identical to the manual counts from a trained investigator and provided a reliable predictor of walking energy expenditure.  相似文献   
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There is a paucity of literature regarding partner violence among males that identifies the sex and relationship of their partner(s). We studied a convenience sample of 54 HIV-infected men, recruited from HIV/AIDS service organizations. Using a standard questionnaire, we collected data on HIV risk behaviours and self-reports of acts of partner violence and forced sex. Physical violence perpetrated by a primary or a casual partner was reported by 39% and 17% of the sample, respectively. Life-time forced sex by a primary or casual partner was reported by 32% and 15% of the sample, respectively. Forced sex was more commonly reported by participants who were non-white and reported a higher number of primary partners in the previous 12 months. We recommend that health care providers be aware of the high rates of intimate partner violence among men infected or at risk of infection with HIV.  相似文献   
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Catecholamine, histamine, and adenosine-mediated accumulations of radioactive cyclic AMP were assessed in adenine-labeled slices from eight rat brain regions. 2-Fluoronorepinephrine, a selective beta-adrenergic agonist, elicited an an accumulation of cyclic AMP in cerebral cortex, cerebellum, hippocampus, striatum, superior colliculi, thalamus, hypothalamus, and medulla-pons. In cerebral cortex and most other brain regions, the beta-adrenergic-mediated response appeared to involve primarily beta 1-adrenergic receptors, while in cerebellum, there was a significant involvement of beta 2-adrenergic receptors. 6-Fluoronorepinephrine, a selective alpha-adrenergic agonist, elicited accumulations of cyclic AMP in all regions except cerebellum. Combinations of the two fluoro derivatives afforded in all brain regions an accumulation of cyclic AMP identical with that elicited by norepinephrine. In hypothalamus, the alpha- and beta-adrenergic responses were significantly greater than additive. In cerebral cortex, the alpha-adrenergic receptor-mediated response appeared to involve alpha 1-adrenergic receptors and to be nearly completely dependent on adenosine, while in other brain regions, the dependence of the alpha-adrenergic response on adenosine was less or absent. Combinations of 6-fluoronorepinephrine and histamine had greater than additive effects in cortex and hippocampus. The results indicate that the interactive control of cyclic AMP-generating systems by alpha-adrenergic, beta-adrenergic, adenosine, and histamine receptors differs significantly among rat brain regions.  相似文献   
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Human papovavirus JC, previously passaged in amnion cells or in primary human fetal glial cells, replicated efficiently in urine-derived epithelial cells. Primary isolation of the virus from brain extracts was possible in urine-derived cells, but these cells were not as sensitive as primary human fetal glial cells for this purpose. Primary isolations of human papovavirus JC from urine sediments of renal transplant patients were made in urine-derived cells.  相似文献   
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