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OBJECTIVE: To investigate whether cardiovascular mortality related to obesity could be modified by physical activity. DESIGN: Mortality follow-up. SETTING: Population study. PARTICIPANTS: Participants in a health survey: 34 868 women and 32 872 men free from known cardiovascular disease or diabetes at baseline. MAIN OUTCOME MEASURES: Total cardiovascular mortality. MAIN RESULTS: During 16 years of follow-up, 3026 women and 3526 men had died from cardiovascular causes. In middle age, obesity [body mass index (BMI) of 30 or higher] was associated with increased risk of cardiovascular death, but the association weakened with age. After 70, there was no association between BMI and cardiovascular death. At all ages, a lower level of physical activity was associated with a higher cardiovascular mortality. In women with high physical activity, indicated by at least 30 min of moderate to vigorous activity more than once a week, cardiovascular mortality was only slightly higher in the obese compared to lean women (adjusted relative risk, 1.27; 95% confidence interval, 0.80-2.00). In men with high physical activity, cardiovascular mortality was, however, significantly higher among the obese (relative risk, 1.62; 95% confidence interval, 1.09-2.40). In both genders cardiovascular mortality was substantially higher in obese people who reported no regular physical activity compared to obese people with a high level of physical activity. CONCLUSION: In obese women, being highly active may, to a large extent, compensate for the risk-increasing effect of being obese, whereas in obese men who engage in a high level of physical activity, the risk of cardiovascular death may be higher than in lean and equally active men.  相似文献   
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Haaga  JR; Beale  SM 《Radiology》1986,161(3):829-830
By injecting small amounts of CO2 through a needle, one can move bowel or bladder from the intended path of instruments during interventional procedures. The technique worked well in six of seven cases in the pelvis and retroperitoneum; it was not effective in the mediastinum or midabdomen (n = 6).  相似文献   
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Abstract: The aim of this study was to evaluate in vitro the dose‐dependent induction potential of six commonly used trade herbal products on CYP2C19 and CYP2E1 metabolic activities in cultured human hepatocytes. S‐mephenytoin and chlorzoxazone were used as specific CYP substrates, respectively, and rifampicin was used as a positive induction control for both enzymes. The hepatocytes were exposed to herbal extracts in increasing and biological relevant concentrations for 72 hrs and CYP substrate metabolites were quantified by validated HPLC methodologies. The major findings were that St John's wort was the most potent CYP‐modulating herb, showing a dose‐dependent induction/inhibition of both CYP2C19 and CYP2E1, with induction at low dosages and inhibition at higher. Ginkgo biloba showed an induction/inhibition profile towards CYP2C19 which was similar but weaker than that observed for St John's wort. If cooperative mechanisms are involved is still an open question. Common sage induced CYP2C19 in a log‐linear dose‐dependent manner with increasing concentrations. Common valerian was a weak inducer of CYP2C19, while horse chestnut and cone flower were characterized as non‐inducers of CYP2C19. Only St John's wort showed an inductive effect towards CYP2E1. In addition to St John's wort, Gingko biloba and common sage should be considered as possible candidates for clinically relevant drug‐herb interactions with selected CYP2C19 substrates.  相似文献   
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外科医生和手术室人员经常接触手术设备产生的烟气,病人也会暴露于烟气中,特别是腹腔镜手术中产生的烟气滞留于腹腔内这一密闭空间并被吸收.这些烟气是一种与香烟烟气相似的毒性物质,然而对这种毒性物质的影响还未引起足够重视.应该采取必要措施尽可能减少手术中烟气的不良影响.  相似文献   
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