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31.
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Objective:

To determine if separation from a father is associated with short-term changes in mental health or substance use in adolescents.

Methods:

Every 3 months, during a 5-year period, we followed 1160 Grade 7 students participating in the Nicotine Dependence in Teens Study who were living with both parents. Participants who reported not living with their father for 6 or more consecutive months during follow-up were categorized as separated from father. Pooled regressions within the framework of generalized estimating equations were used to model the associations between separation from father and indicators of mental health (depressive symptoms, and worry and [or] stress about family relationships or the family situation) and substance use (alcohol use and cigarette smoking) 4 to 6 and 7 to 9 months postseparation, controlling for age, sex, and baseline level of the outcome variable.

Results:

Compared with adolescents living with both parents, adolescent offspring separated from their fathers were more likely to report depressive symptoms (β = 0.17, 95% CI 0.01 to 0.33) 4 to 6 months postseparation, as well as worry and (or) stress about their parents separating or divorcing (OR 2.39, 95% CI 1.29 to 4.43), a new family (OR 4.25, 95% CI 2.33 to 7.76), and the family financial situation (OR 2.35, 95% CI 1.53 to 3.60). Separation from father was also marginally significantly related to worry and (or) stress about their relationship with their father (OR 1.53; 95% CI 0.98 to 2.39). At 7 to 9 months postseparation, separation from father continued to be associated with worry and (or) stress about their parents separating or divorcing, a new family, and the family financial situation. Separation from father was no longer associated with worry and (or) stress about their relationship with their father, but it was associated with worry and (or) stress about their relationship with their mother. Separation from father was not related to use of alcohol or cigarettes.

Conclusion:

Adolescent offspring experienced family-related stress and transient depression symptoms in the 4- to 9-month period following separation from their fathers.  相似文献   
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Although the 2008 food price crisis presumably plunged millions of households into poverty and food insecurity, the real impact of the crisis has rarely been documented using field data. Our objective was to assess the consequences of this crisis for household food insecurity and dietary diversity in urban Burkina Faso. Two cross-sectional surveys were conducted among randomly selected households in Ouagadougou in July 2007 (n = 3017) and July 2008 (n = 3002). At each round, food insecurity assessed by the Household Food Insecurity Access Scale (HFIAS), the Dietary Diversity Score of an index-member of the household (IDDS = number of food groups consumed in the last 24 h), and food expenditure were collected. Food prices of the 17 most frequently consumed food items were recorded throughout the study area. Food prices at local markets increased considerably between 2007 and 2008, especially those of fish (113%), cereals (53%), and vegetable oil (44%), increasing the household monthly food expenditure by 18%. Thirty-three percent of households were food secure in 2007 and 22% in 2008 (P = 0.02). Individuals consumed fewer fruits and vegetables, dairy products, and meat/poultry in 2008 than in 2007 (mean IDDS = 5.7 ± 1.7 food groups in 2007 vs. 5.2 ± 1.5 in 2008; P < 0.0001). Differences in IDDS and HFIAS between the 2 y were even more marked after adjustment for confounding factors and food expenditure. Food security and dietary diversity significantly decreased between 2007 and 2008, whereas food prices increased. Households increased their food expenditure, but this was not sufficient to compensate the effects of the crisis.  相似文献   
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BACKGROUND: While normal at rest, left ventricular (LV) systolic function may become abnormal during exercise in patients with aortic stenosis. Once contraindicated in patients with aortic stenosis, exercise testing is now recommended in asymptomatic patients with aortic stenosis to elicit symptoms and thereby ascertain the need for aortic valve replacement. However, the clinical significance of an abnormal LV response to exercise in asymptomatic patients with aortic stenosis remains unknown. OBJECTIVE: The aim of this study was to evaluate the clinical implications of an abnormal LV response during exercise in the setting of aortic stenosis. METHODS: We monitored the LV response to exercise by 2D-Doppler echocardiography during a symptom limited semirecumbent bicycle exercise in 50 patients with tight aortic stenosis (aortic valve area < or = 1.0 cm(2)) and a normal LV systolic function (LV ejection fraction, EF > or = 50%) and followed them for an average of 11 months. RESULTS: Twenty patients had an abnormal LV response to exercise with a mean decrease in LV EF from 64 +/- 10 to 53 +/- 12% while 30 patients had a normal LV response to exercise with a mean increase in LV EF from 62 +/- 7 to 70 +/- 8%. Patients with an abnormal LV response during exercise were more likely to develop symptoms during exercise than patients with a normal LV response: 80% versus 27% (P< 0.0001). The survival free of cardiac events was significantly lower in patients with abnormal LV response to exercise than in patients with a normal response (P = 0.03). CONCLUSION: Exercise echocardiography provides objective data that facilitate interpretation of exercise elicited symptoms in asymptomatic patients with severe aortic stenosis. In addition, an abnormal LV response to exercise may predict a poor outcome.  相似文献   
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The supply of naive T cells by the thymus normally requires precursor T cell proliferation within the thymus and would be particularly important in the setting of HIV infection when both naive and memory T cells are progressively depleted. As a robust, quantitative index of intrathymic proliferation, the ratio of different T cell receptor excision circles (TRECs), molecular markers of distinct T cell receptor rearrangements occurring at different stages of thymocyte development, was measured in peripheral blood-mononuclear cells (PBMCs). This ratio has the virtue that it is a "signature" of thymic emigrants throughout their entire life and, thus, can be measured in peripheral cell populations that are easy to obtain. Using the new assay, we evaluated the effect of HIV infection on intrathymic precursor T cell proliferation by longitudinal analysis of PBMCs from recently infected individuals. Our findings reveal a substantial reduction in intrathymic proliferation. The analysis also indicates the existence of a compensatory mechanism acting to sustain the numbers of recent thymic emigrants (RTEs) in the periphery.  相似文献   
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We evaluated radiographs of the hands of 20 pianists. The radiologic manifestations arising from long-term stress and strain applied to the hands were recorded. The changes are characterized by: 1) alignment adaptation consisting of axial radial rotation of the digits, particularly the fifth but also the third and fourth, 2) degenerative changes at the distal interphalangeal DIP and metacarpophalangeal MCP joints, and 3) mechanical remodeling manifested as periostal thickening and flattening of the phalangeal tufts associated with sclerosis. These findings suggest the existence of an occupational entity which might be described as pianist's osteoarthropathy.  相似文献   
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