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951.
Labour force participation has been identified as a critical social and health issue facing people living with HIV/AIDS (PHAs). We conducted a scoping study (a form of literature synthesis that summarizes research findings, research activity, and identifies literature strengths and gaps) on labour force participation for PHAs, guided by a community advisory committee. We summarized information from 243 peer-reviewed articles and 42 reports from the grey literature, and synthesized the evidence into a preliminary conceptual framework with five components: (1) the meaning of work, (2) key factors (barriers and facilitators) influencing labour force participation, (3) factors affecting vulnerable populations, (4) strategies and supports for returning to or sustaining work, and (5) outcomes (benefits and risks) of labour force participation for individuals and employers. The framework supports the development of labour force initiatives requiring collaborative efforts in multiple domains (health, employment, community) by PHAs, rehabilitation professionals, employers, insurers, and policy makers.  相似文献   
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Monitoring air pollution: use of early warning systems for public health   总被引:1,自引:0,他引:1  
Research confirming the detrimental impact poor ambient air quality and episodes of abnormally high pollutants has on public health, plus differential susceptibility, calls for improved understanding of this complex topic among all walks of society. The public and particularly, vulnerable groups, should be aware of their quality of air, enabling action to be taken in the event of increased pollution. Policy makers must have a sound awareness of current air quality and future trends, to identify issues, guide policies and monitor their effectiveness. These attitudes are dependent upon air pollution monitoring, forecasting and reporting, serving all interested parties. Apart from the underlying national regulatory obligation a country has in reporting air quality information, data output serves several purposes. This review focuses on provision of real-time data and advanced warnings of potentially health-damaging events, in the form of national air quality indices and proactive alert services. Some of the challenges associated with designing these systems include technical issues associated with the complexity of air pollution and its science. These include inability to provide precise exposure concentrations or guidance on long-term/cumulative exposures or effects from pollutant combinations. Other issues relate to the degree to which people are aware and positively respond to these services. Looking to the future, mobile devices such as cellular phones, equipped with sensing applications have potential to provide dynamic, temporally and spatially precise exposure measures for the mass population. The ultimate aim should be to empower people to modify behaviour-for example, when to increase medication, the route/mode of transport taken to school or work or the appropriate time to pursue outdoor activities-in a way that protects their health as well as the quality of the air they breathe.  相似文献   
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Background Altered methyl group and homocysteine metabolism were tissue‐specific, persistent, and preceded hepatic DNA hypomethylation in type 1 diabetic rats. Similar metabolic perturbations have been shown in the Zucker (type 2) diabetic fatty (ZDF) rat in the pre‐diabetic and early diabetic stages, but tissue specificity and potential impact on epigenetic marks are unknown, particularly during pathogenesis. Methods ZDF (fa/fa) and lean (+/?) control rats were killed at 12 and 21 weeks of age, representing early and advanced diabetic conditions. Blood and tissues were analysed with respect to methyl group and homocysteine metabolism, including DNA methylation. Results At 12 weeks, hepatic glycine N‐methyltransferase (GNMT), methionine synthase, and cystathionine β‐synthase (CBS) activity and/or abundance were increased in ZDF rats. At 21 weeks, GNMT activity was increased in liver and kidney; however, only hepatic CBS protein abundance (12 weeks) and betaine‐homocysteine S‐methyltransferase mRNA expression (21 weeks) were significantly elevated (78 and 100%, respectively). Hepatic phosphatidylethanolamine N‐methyltransferase expression was also elevated in the ZDF rat. Homocysteine concentrations were decreased in plasma and kidney, but not in liver, at 12 and 21 weeks. In contrast to hepatic DNA hypomethylation in the type 1 diabetic rat, genomic DNA was hypermethylated at 12 and 21 weeks in the liver of ZDF rats, concomitant with an increase in DNA methyltransferase 1 expression at 21 weeks. Conclusions The pathogenesis of type 2 diabetes in the ZDF rat was associated with tissue and disease stage‐specific aberrations of methyl group and homocysteine metabolism, with persistent hepatic global DNA hypermethylation. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
955.
Adipokines secreted by visceral, subcutaneous, and perivascular adipocytes are involved in the regulation of vascular tone by acting as circulatory hormones (leptin, adiponectin, omentin, visfatin, angiotensin II, resistin, tumor necrosis factor-α, interleukin-6, apelin) and/or via local paracrine factors (perivascular adipocyte-derived relaxing and contractile factors). Vascular tone regulation by adipokines is compromised in obesitas and obesity-related disorders. Hypoxia created in growing adipose tissue dysregulates synthesis of vasoactive adipokines in favor of harmful proinflammatory adipokines, while the levels of the cardioprotective adipokines adiponectin and omentin decrease. Considering the potential of the role of adipokines in obesity-related vascular diseases, strategies to counter these diseases by targeting the adipokines are discussed.  相似文献   
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