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1.
Although studies have documented underuse of controller medications and overuse of short-acting inhaled ss(2)-agonist among children with persistent asthma in disadvantaged communities, the persistence of oral ss(2)-agonist use in pediatric practice has not been studied since inhaled short-acting ss(2)-agonists became widespread. We describe medications used to treat asthma among children 3 to 5 years of age at 10 Head Start and other subsidized preschool centers in East and Central Harlem, New York City. We interviewed 149 parents/guardians of children who were identified as having probable asthma based on physician's diagnosis, persistent symptoms, hospitalization, and medication use. We classified 86 of the 149 children (58%) as having current persistent asthma. Only 15 of them (17%) were reported to have used controller medications at least 5 days/week in the last 4 weeks-only 2 of whom used inhaled corticosteroids. By contrast, 53 children (62%) used oral ss(2)-agonist in the last 4 weeks, often (72%) in conjunction with nebulized or inhaled short-acting ss(2)-agonist. Use of oral ss(2)-agonist was associated with more severe symptoms. This study documents the continued widespread use of oral ss(2)-agonist for treatment of children in a low-income community with high prevalence of asthma.  相似文献   
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We have used a novel method to identify genes expressed in the hypothalamus which may be potentially involved in controlling food intake and energy metabolism. We assumed that food deprivation, a powerful stimulus of food intake, would stimulate the activity of neural pathways involved in feeding behavior which should be reflected in an increase in the synthesis of any relevant neuropeptide and its messenger RNA. A study of 5 neuropeptides in 5 strains of mice has identified neuropeptide Y (NPY) as a gene whose expression in the hypothalamus is controlled by nutritional status, suggesting that hypothalamic NPY neurons are a link in the neural network regulating feeding behavior and energy metabolism. In addition, we have studied the effect of the diabetes mutation on neuropeptide gene expression during fasting and refeeding. Our findings suggest that abnormal NPY and enkephalin gene expression in the hypothalamus may be two important determinants of the expression of the diabetes mutation.  相似文献   
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BACKGROUND: Cardiac rehabilitation (CR) has an evidence base but traditional models may not readily apply to people living in rural and remote regions. AIM:: To outline published comprehensive and non-hospital based CR models used for people discharged from hospital after a cardiac event that have potential relevance to those living in rural and remote areas in Australia. METHODS: The PubMed database was searched using Medical subject headings (MeSH) terms and the key word 'cardiac rehabilitation' limited to clinical trials. Articles were retrieved if they included at least two components of CR and were not based in an outpatient setting. RESULTS: No CR models specifically developed for rural and remote areas were identified. However, 14 studies were found that outlined 11 non-conventional comprehensive CR models. All provided CR in a home-based setting. Health professionals provided support via telephone contact or home visits, and via resources such as the Heart Manual. Reported outcomes from these CR programs varied: ranging from an increase in knowledge of risk factors, to improvements in physical activity, decreased risk factor profile, improved psychological and social functioning and reductions in health service costs and mortality. CONCLUSION: Home-based, CR models have the most substantive evidence base and, therefore the greatest potential to be developed and made accessible to eligible people living in rural and remote areas.  相似文献   
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This study compared the predictive value of the theory of planned behavior in university students in South Africa (N = 251) and the United States (N = 160) who completed an anonymous self-administered questionnaire. Multiple regression analyses revealed that condom use and intention were significantly predicted by positive condom attitude, subjective norm, self-efficacy, and attending university in South Africa. Significant interactions between country and predictors indicated that subjective norm predicted condom use and intention more strongly in the American sample than in the South African sample; attitude predicted intention more strongly in the American sample than in the South African sample; but self-efficacy predicted intention more strongly in the South African sample than in the American sample. The theory of planned behavior may provide a useful framework for interventions to reduce South African students' risk of HIV/and sexuality transmitted diseases. Such interventions should especially focus on building self-efficacy to use condoms.  相似文献   
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Background  

Pulmonary dysfunction following cardiac surgery is believed to be caused, at least in part, by a lung vascular injury and/or atelectasis following cardiopulmonary bypass (CPB) perfusion and collapse of non-ventilated lungs.  相似文献   
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Clinical practice guidelines have been proposed to significantly reduce the gap between available scientific evidence and clinical practice. Evidence-based guidelines are also being produced at an ever-increasing pace. However, guidelines do not implement themselves, and the research to support implementation does not provide straightforward answers. What works in one setting does not necessarily work in another. In short, guideline implementation and change of practice is complex and messy. The purpose of this article is to discuss the implementation of clinical practice guidelines using the Promoting Action on Research Implementation in Health Services framework. More specifically, 3 key components are highlighted: (1) the evidence base for guideline recommendations, (2) the clinical context where guidelines are to be implemented, and (3) the nature of facilitation needed to ensure a successful change process. An overview of the literature in the field is provided, and the authors' experiences are shared, and a few recommendations are tentatively provided.  相似文献   
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Greater body fatness during childhood is associated with reduced risk of premenopausal breast cancer, but few studies have addressed the relation of adiposity with sex hormones in girls. We prospectively examined associations between adiposity and circulating levels of sex hormones and sex hormone-binding globulin (SHBG) among 286 girls in the Dietary Intervention Study in Children. Participants were 8 to 10 years old at baseline and were followed for an average of 7 years. Anthropometric measurements were taken at baseline and at subsequent annual visits, and blood samples were collected every 2 years. Concentrations of dehydroepiandrosterone sulfate (DHEAS) during follow-up were higher among girls with greater body mass index (BMI) at baseline. The mean for the lowest BMI quartile was 63.0 microg/dL compared with 78.8 microg/dL for the highest quartile, and each kg/m(2) increment in baseline BMI was associated with a 4.3% increase (95% confidence interval, 1.6-7.0%) in DHEAS levels during follow-up (P(trend) = 0.002). Concentrations of SHBG during follow-up were lower among girls with greater BMI at baseline. The mean for the lowest BMI quartile was 94.8 nmol compared with 57.5 nmol for the highest quartile, and each kg/m(2) increment in baseline BMI was associated with an 8.8% decrease (95% confidence interval, 7.0-10.6%) in SHBG levels during follow-up (P(trend) < 0.0001). Estrogen and progesterone concentrations were similar across BMI quartiles. These findings suggest that adiposity may alter DHEAS and SHBG levels in girls. Whether and how these differences affect breast development and carcinogenesis requires further research.  相似文献   
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