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991.
The out-of-range error in microdensitometry 总被引:2,自引:0,他引:2
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Marilyn C. Cornelis Stephanie E. Chiuve M. Maria Glymour Shun-Chiao Chang Eric J. Tchetgen Tchetgen Liming Liang Karestan C. Koenen Eric B. Rimm Ichiro Kawachi Laura D. Kubzansky 《PloS one》2014,9(9)
While research has suggested that being married may confer a health advantage, few studies to date have investigated the role of marital status in the development of type 2 diabetes. We examined whether men who are not married have increased risk of incident type 2 diabetes in the Health Professionals Follow-up Study. Men (n = 41,378) who were free of T2D in 1986, were followed for ≤22 years with biennial reports of T2D, marital status and covariates. Cox proportional hazard models were used to compare risk of incident T2D by marital status (married vs unmarried and married vs never married, divorced/separated, or widowed). There were 2,952 cases of incident T2D. Compared to married men, unmarried men had a 16% higher risk of developing T2D (95%CI:1.04,1.30), adjusting for age, family history of diabetes, ethnicity, lifestyle and body mass index (BMI). Relative risks (RR) for developing T2D differed for divorced/separated (1.09 [95%CI: 0.94,1.27]), widowed (1.29 [95%CI:1.06,1.57]), and never married (1.17 [95%CI:0.91,1.52]) after adjusting for age, family history of diabetes and ethnicity. Adjusting for lifestyle and BMI, the RR for T2D associated with widowhood was no longer significant (RR:1.16 [95%CI:0.95,1.41]). When allowing for a 2-year lag period between marital status and disease, RRs of T2D for widowers were augmented and borderline significant (RR:1.24 [95%CI:1.00,1.54]) after full adjustment. In conclusion, not being married, and more specifically, widowhood was more consistently associated with an increased risk of type 2 diabetes in men and this may be mediated, in part, through unfavorable changes in lifestyle, diet and adiposity. 相似文献
994.
Cornelis M. Vos Gerrit Westera Benjamin van Zanten 《Journal of inorganic biochemistry》1980,12(1):45-55
Chromatographic analysis of Co-bleomycin on CM Sephadex C25 or silica shows that known components like bleomycin A2, B2, and A1 can be separated into two forms. We observed an equilibrium between both forms and saw that the addition of certain salts influences the transition of one form into the other. A reaction scheme is suggested in which a different occupation of the sixth binding site of cobalt is correlated with the different forms observed. These different complexes may be an intramolecular adduct of the carbamoyl moiety of bleomycin, an external carboxylate adduct or an oxygen or hydroxyl adduct. 相似文献
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Cornelis M. Visser 《Bioorganic chemistry》1980,9(4):411-422
Origin of life considerations can be useful for understanding function and mechanism in metabolism of present cofactors. An important role is postulated for chromanols such as tocopherol in the transition from anaerobic to aerobic metabolism, this transition being a critical point in evolution. The antioxidant and amphipathic properties of such molecules make them plausible candidates for dioxygen detoxification within membranes of the earliest respiratory systems. In the light of this, the possibility is examined that tocopherol still plays such a role of a detoxicating dioxygen carrier within membranes. In addition, a mechanism for vitamin K-dependent carboxylation is suggested in line with the proposal for vitamin E and in accord with the present state of experimental knowledge. 相似文献
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