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Objective  

To estimate the duration of work life among persons reporting a physician's diagnosis of COPD, asthma, or rhinitis compared to those with select non-respiratory conditions or none and to delineate the factors associated with continuance of employment.  相似文献   
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Angiodysplasia of gastrointestinal tract is still thought to be an entity of unknown aetiology. This lesion is most commonly observed in elderly patients presenting with severe and persistent iron deficiency anaemia, following occult blood loss or acute episodes of haematemesis. In the stomach antral vascular ectasia is the most common presentation. We report an autopsy case of vascular ectasia in the cardia of stomach in a young patient with clinical symptoms of anaemia as the presentation and an associated secondary hemosiderosis of liver.  相似文献   
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Mouse mammary epithelial cells (HC-11) and mammary tissues were analyzed for developmental changes in circadian clock, cellular proliferation, and differentiation marker genes. Expression of the clock genes Per1 and Bmal1 were elevated in differentiated HC-11 cells, whereas Per2 mRNA levels were higher in undifferentiated cells. This differentiation-dependent profile of clock gene expression was consistent with that observed in mouse mammary glands, as Per1 and Bmal1 mRNA levels were elevated in late pregnant and lactating mammary tissues, whereas Per2 expression was higher in proliferating virgin and early pregnant glands. In both HC-11 cells and mammary glands, elevated Per2 expression was positively correlated with c-Myc and Cyclin D1 mRNA levels, whereas Per1 and Bmal1 expression changed in conjunction with beta-casein mRNA levels. Interestingly, developmental stage had differential effects on rhythms of clock gene expression in the mammary gland. These data suggest that circadian clock genes may play a role in mouse mammary gland development and differentiation.  相似文献   
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The relationship between work rate () and time to exhaustion (t) during intense exercise is commonly described by either a hyperbolic function (NLin), t=W /(? cp), or by its linear equivalent (LinW) W lim =W + cp(t). The parameter <INF cp (critical power) has been described as an inherent characteristic of the aerobic energy system, while W?′ has been shown to be a ralid estimate of anaerobic work capacity. Recent studies have demonstrated that oral supplementation of creatine monohydrate (CrH2O) increases total muscle creatine stores, and have linked these increases to improved performances in intense intermittent exercise. This study was conducted to determine the effect of CrH2O supplementation on estimates of W?′ and <INF cp derived from the NLin and LinW equations, and to determine the effect of CrH2O on t in exhaustive constant power exercise of different intensities. Fifteen active but untrained university students completed three phases of testing on a cycle ergometer: (1) familiarization, three learning trials, (2) baseline determination of W?′ and <INF cp, four bouts performed at a selected to elicit fatigue in 90–600?s, and (3) experimental determination of W?′ and cp, four bouts performed at the same as baseline, but performed after 5 days of ingesting either a placebo (4?×?6?g of glucose/day) or CrH2O (4?×?5?g of CrH2O and 1?g glucose/day). Testing was administered in a double-blind manner. Analyses of covariance revealed a significant effect for CrH2O on both estimates of W?′ (NLin, P=0.04; LinW, P<0.01), but not on estimates of cp (NLin, P=0.37; LinW; P=0.30). Within groups, t was significantly different for only CrH2O at the two highest s (P=0.04). It is concluded that oral ingestion of CrH2O increases estimates of W?′ due to an improved t at the shorter, more intense exercise bouts.

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