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991.
我国正常生育力男子精浆的微量元素研究   总被引:12,自引:5,他引:7  
本文报告测试了68例正常生育力成年男子精浆中的锌、铜,铁等微量元素和镁,测试结果如下:锌130±5.64μg/ml,铜1.84±0.158μg/ml,铁0.801±0.104μg/ml,镁103.86±10.01μg/ml。所测得的数值均在正常范围内。在正常范围内的精液,精浆中的锌、镁含量与精液质量(精子密度和活动力)之间无显著差异。但铜的含量与精子活动度关系密切,含量高则活动度差,反之则活动度好。铁的含量与精子密度关系也十分密切,含量高时精子密度也高。  相似文献   
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993.
A simple and specific high-performance liquid chromatographic (HPLC) method was developed for the pharmacokinetic study of vitexin-2'-O-rhamnoside (VOR) in rat after intravenous administration. The plasma samples were deproteinized with methanol after addition of internal standard (i.s.) hesperidin. HPLC analysis was performed on a Diamonsil ODS C18 analytical column, using acetonitrile-0.3% formic acid (20:80, v/v) as the mobile phase with UV detection at 270 nm. The standard curve was linear over the range of 0.1070-21.41 microg/mL in rat plasma. The average extraction recovery of VOR was 97.9+/-3.1%, and the relative standard deviations (R.S.D.s) of the intra- and inter-day precisions were no more than 7.4 and 8.5%, respectively. The lower limit of quantification (LLOQ) was 0.1070 microg/mL. The AUC of VOR was proportional to the dose after intravenous administration of 15, 30, 60 and 120 mg/kg body weight, and the elimination half-life (t1/2beta), systemic clearance (Cl) and apparent volume of distribution (Vc) were not significantly different among the four doses, and all the results indicated that the pharmacokinetics of VOR in rat obeyed first-order kinetics.  相似文献   
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996.
Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) has potent effects in the brain as a free radical scavenger in ischemia-reperfusion (IR) injuries. However, whether this free radical scavenger can prevent myocardial injury after cerebral IR is not clear. The aim of the present study was to investigate the effect of edaravone against oxidative damage in brain-to-heart signaling triggered by IR injury and its possible mechanism. In this study, the expression of glutathione peroxidase (GSHPx) and protein carbonyl content was examined to evaluate oxidative stress. The activation of mitogen-activated protein kinases (MAPKs) was also examined. Terminal deoxynucleotidyl transferase nick-end labeling (TUNEL) analysis was performed to estimate cardiomyocytes cell death. After edaravone treatment there was a mild increase in activities of GSHPx in cardiomyocytes; however, there was a decrease in protein carbonyl content. p38 MAPK activity was inhibited by edaravone treatment in comparison with the vehicle group in myocardium. These results were further complemented by a significant reduction of TUNEL-positive cells in the heart sections. Our results demonstrate that edaravone provides ameliorative effects in the myocardium after cerebral IR injury by differentially modulating MAPK's activity, thus reducing the oxidative stress state.  相似文献   
997.
A new sesquiterpene lactone with an unusual sulfonic acid group, 13-sulfo-dihydrodehydrocostus lactone (1), was isolated from the roots of Saussurea lappa C. (Compositae), together with a known lignan (2). The structure of 1 was characterized on the basis of spectral evidence including 2DNMR studies. Compound 2 was obtained from this plant for the first time.  相似文献   
998.
Advances in the understanding of glioma pathogenesis have led to increasing interest in the development of targeted molecular agents, and especially kinase inhibitors, for treatment of malignant gliomas. Protein kinases are a large family of enzymes that function as key regulators of cellular signaling pathways governing diverse functions, such as cell proliferation, growth, differentiation, invasion, angiogenesis and apoptosis in malignant gliomas. Preliminary clinical results with kinase inhibitors suggest that they are generally well-tolerated but have shown only modest activity. However, valuable information was obtained from these early clinical trials that will help the future development of these agents. This article reviews the important protein kinases in malignant gliomas, summarizes the existing clinical development of kinase inhibitors and discusses strategies to improve their effectiveness.  相似文献   
999.
Dietary flavonoids and other polyphenols have the potential to be developed as effective food supplements as well as drugs for the prevention, as well as treatment of, cancer and other disease conditions. However, their very poor oral bioavailability, mainly due to extensive conjugation by glucuronidation and sulfation, is a severe limiting factor. First, this review shows the use of a simple, commercially available model system, the human hepatic S9 fraction, by which metabolic stability can be assessed effectively and accurately. Second, permethylation of the polyphenols effectively blocks the metabolic conjugation reactions, thereby dramatically increasing both metabolic stability and intestinal absorption, while maintaining or even increasing the biologic activities. Thus, permethylated polyphenols may have a future as chemoprotective agents.  相似文献   
1000.
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