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101.
Gene expression of antioxidant enzymes in experimental diabetic neuropathy   总被引:6,自引:0,他引:6  
Chronic hyperglycemia results in a large deficit in nerve blood flow. Both autoxidative- and ischemia-induced lipid peroxidation occurs, with resultant peripheral sensory neuropathy in streptozotocin-induced diabetes in the rat. Free radical defenses, especially involving antioxidant enzymes, have been suggested to be reduced, but scant information is available on chronic hyperglycemia. We evaluated the gene expression of glutathione peroxidase, catalase, and superoxide dismutase (cuprozinc and manganese separately) in L4,5 dorsal root ganglion (DRG) and superior cervical ganglion, as well as enzyme activity of glutathione peroxidase in DRG and sciatic nerve in experimental diabetic neuropathy of 3 months and 12 months durations. We also evaluated nerve electrophysiology of caudal, sciatic-tibial, and digital nerves. A nerve conduction deficit was seen in all nerves in experimental diabetic neuropathy at both 3 and 12 months. Gene expression of glutathione peroxidase, catalase, cuprozinc superoxide dismutase, and manganese superoxide dismutase were not reduced in experimental diabetic neuropathy at either 3 or 12 months. Catalase mRNA was significantly increased in experimental diabetic neuropathy at 12 months. Glutathione peroxidase enzyme activity was normal in sciatic nerve. We conclude that gene expression is not reduced in peripheral nerve tissues in very chronic experimental diabetic neuropathy. Changes in enzyme activity may be related to duration of diabetes or due to post-translational modifications.  相似文献   
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近15年来,澳大利亚对职业教育与培训进行了全面的的改革,现已拥有高度竞争力和灵活性的人力资源。这在一定程度上为澳大利亚的持续经济繁荣作出了贡献。改革后,澳大利亚的国民经济增长率在经济合作发展组织中一直名列前茅。中国有关方面的政策制定者和教育工作者,可以借鉴澳大利亚的成功经验和模式,发展和完善职业教育和培训体制,使其更高效、反应更迅速。  相似文献   
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The objective of this study was to assess the validity and observed effect size of a new instrument, the Optimality Index-United States (OI-US), for use in perinatal clinical research. Using a large, hospital-based, midwifery service clinical database that included complete obstetric data for 3425 women, we examined discriminant validity and the effects of two different scoring methods used with the OI-US. Discriminant validity was confirmed by comparing OI scores for women who remained low risk and did not require physician involvement in their care (OI score mean = 84%; standard deviation [SD] = 8%) compared to those whose condition changed to require physician involvement in their care (mean = 71%; SD = 10%; P < .001). Two methods of scoring the OI-US were compared, finding no significant difference and suggesting that the types of data available and the research question can drive this decision. Finally, effect size was calculated by two methods: Cohen's d (-1.4) and the effect size correlation (r = -0.548), the latter of which corresponds to a d of -1.3, both resulting in a similarly large effect size estimation. The OI-US is a new instrument that shows promise for use in perinatal clinical research, particularly when assessing more subtle clinical differences in outcomes between study groups.  相似文献   
105.
Our objective was to address the gap in knowledge about the extent to which perinatal mental health and risk behaviors are associated with childhood and adult experiences of abuse that arises because of barriers to screening and disclosure about past and current abuse. Survey data from an ongoing study of the effects of posttraumatic stress on childbearing were used to describe four groups of nulliparous women: those with no abuse history, adult abuse only, childhood abuse only, and abuse that occurred during both periods. The rates of abuse history disclosure were higher in the research context than in the clinical settings. Mental health morbidity and risk behaviors occurred in a dose-response pattern with cumulative abuse exposure. Rates of current posttraumatic stress disorder ranged from 4.1% among those never abused to 11.4% (adult only), 16.0% (childhood only), and 39.2% (both periods). Women abused during both periods also were more likely to be using tobacco (21.5%) and drugs (16.5%) during pregnancy. We conclude that mental health and behavioral risk sequelae affect a significant portion of both childhood and adult abuse survivors in prenatal care. The integration into the maternity setting of existing evidence-based interventions for the mental health and behavioral sequelae of abuse is needed.  相似文献   
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