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Recent finding suggest that many fetuses have to adapt to a limited supply of nutrients and in doing so they permanently change their physiology and metabolism. These 'programmed' changes may be the origins of a number of diseases in life, including coronary heart disease and the related disorders stroke, diabetes and hypertension. 相似文献
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I CHURCHILL-DAVIDSON C SANGER RH THOMLINSON 《Canadian Metallurgical Quarterly》1955,268(6874):1091-1095
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YT Zhou M Shimabukuro K Koyama Y Lee MY Wang F Trieu CB Newgard RH Unger 《Canadian Metallurgical Quarterly》1997,94(12):6386-6390
We have studied mechanisms by which leptin overexpression, which reduces body weight via anorexic and thermogenic actions, induces triglyceride depletion in adipocytes and nonadipocytes. Here we show that leptin alters in pancreatic islets the mRNA of the genes encoding enzymes of free fatty acid metabolism and uncoupling protein-2 (UCP-2). In animals infused with a recombinant adenovirus containing the leptin cDNA, the levels of mRNAs encoding enzymes of mitochondrial and peroxisomal oxidation rose 2- to 3-fold, whereas mRNA encoding an enzyme of esterification declined in islets from hyperleptinemic rats. Islet UCP-2 mRNA rose 6-fold. All in vivo changes occurred in vitro in normal islets cultured with recombinant leptin, indicating direct extraneural effects. Leptin overexpression increased UCP-2 mRNA by more than 10-fold in epididymal, retroperitoneal, and subcutaneous fat tissue of normal, but not of leptin-receptor-defective obese rats. By directly regulating the expression of enzymes of free fatty acid metabolism and of UCP-2, leptin controls intracellular triglyceride content of certain nonadipocytes, as well as adipocytes. 相似文献
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Following the same general principles of its two predecessors in 1973 and 1986, the 1996 National Roadside Survey of weekend, nighttime drivers in the 48 contiguous states interviewed and breath tested over 6000 noncommercial four-wheel vehicle operators between September 6 and November 9, 1996. Results indicated that the total number of drinking drivers fell by about one-third between 1986 and 1996; however, there was no significant change in the number of drivers at blood alcohol concentrations (BACs) at or above 0.05. Compared to 1973, the proportion of women drivers on the roads during weekend nights has increased significantly. Moreover, relative to males, the proportion of female drivers who have been drinking has increased over the last decade. The number of drivers under the age of 21 with a BAC at or above 0.10 decreased significantly from 1986 to 1996. 相似文献