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41.
剧烈运动时自由基的大量生成与清除能力下降是导致运动性疲劳和运动性损伤的主要原因之一。抗氧化酶在保护机体免受自由基损伤中发挥着重要的作用。运动训练能增加抗氧化酶的活性,提高机体清除自由基的能力。不同抗氧化酶对不同运动训练的反应不同。本文通过文献查阅的方法,对国内外学者近年来关于运动训练对抗氧化酶影响的研究进行综述,为该领域的研究提供一定的理论指导。  相似文献   
42.
目的:研究小鼠衰老时肾脏线粒体形态、结构、功能及mtDNA的变化规律,观察有氧运动训练和抗氧化剂延缓肾脏老化的效果.方法:用电镜对线粒体观察计数,Clark氧电极法测定线粒体呼吸链CytC氧化酶及NADH脱氢酶活性,分光光度法测定抗氧化酶活性,聚合酶链反应检测mtDNA3866bp片段缺失率.结果:与5月龄小鼠比较,20月龄的老年小鼠肾脏线粒体数量减少、体积增大,线粒体呼吸控制率、ADP/O比值减小,呼吸链NADH脱氢酶、CytC氧化酶活性下降,mtDNA3866bp片段缺失率增加,而抗氧化酶活性却增大.结论:长期进行有氧运动和/或补充抗氧化剂可在一定程度上维持机体氧化与抗氧化的平衡,延缓mtDNA片段缺失率随增龄积累,预防线粒体老化,改善线粒体功能.  相似文献   
43.
The effects of process variables such as enzyme types, enzyme ratio, reaction temperature, pH, time, and ethanol concentration on the extraction of unripe apple polyphenol were investigated. The results indicated that Viscozyme L had the strongest effect on polyphenols extraction and was selected to study the polyphenol composition. The ratio of enzyme (Viscozyme L) to substrate (2 fungal beta-glucanase units (FBG)) at 0.02, reaction at pH 3.7,50 ℃ for 12 h, and ethanol concentration of 70% were chosen as the most favorable extraction condition. Total phenolic content (TPC), reducing sugar content (RSC), and extraction yield increased by about 3,1.5, and 2 times, respectively, compared with control. The contents of p-coumaric acid, ferulic acid, and caffeic acid increased to 8,4, and 32 times, respectively. The enzyme-aided polyphenol extraction process from unripe apples might be applied to food industry for enhancing bioactive compound production.  相似文献   
44.
The role of oxidant damage to red cells in sickle cell anaemia has been of interest in recent years. Although, available reports suggest that sickle cell erythrocytes are susceptible to endogenous free radical mediated oxidant damage there remains discrepancy in the status of antioxidant enzymes and antioxidant vitamins in these patients. In view of this, 107 cases of sickle cell anaemia (36 ‘SS’ and 71 ‘AS’ pattern—as confirmed by haemoglobin electrophoresis) were subjected to analysis of malondialdehyde, ascorbic acid, superoxide dismutase and albumin. The results were compared with 54 age and sex matched healthy controls. The results indicate a marked increase in lipid peroxidation and superoxide dismutase levels in both ‘SS’ and ‘AS’ types of sickle cell anaemia as compared to controls. Although no difference was observed in the levels of albumin in these groups the levels of ascorbic acid were significantly depleted in sickle cell anaemia patients. The results are indicative of enhanced lipid peroxidation along with imbalance in the pro-oxidant and antioxidant status in patients of sickle cell anaemia.  相似文献   
45.
Diabetes has been classified as a disease of glucose overproduction by tissues, mainly liver and glucose underutilization by insulin requiring tissues like liver, adipose and muscle due to lack of insulin. There is, however, glucose over utilization in tissues not dependent on insulin for glucose transport like kidney, nerve and brain. There are serious complications due to this excess glucose in these tissues and their reversal is important for a good metabolic control and normalisation of other parameters. Insulin, trace metals and some plant extracts have been used to see the reversal effects of the complications of diabetes in liver and kidney in experimental diabetes. Almost complete reversal of the metabolic changes has been achieved in the activities of key enzymes of metabolic pathways in liver and kidney and an effective glucose control has been achieved suggesting a combination of therapies in the treatment of metabolic disturbance of the diabetic state.  相似文献   
46.
Pathogens, especially Gram-negative bacteria or bacterial endotoxin, along with other classical factors, may be involved in inflammatory response within the aortic endothelium during the progression of cardiovascular disease. Studies have shown that bacterial endotoxin activates various inflammatory processes in the body. Our study aims to establish a correlation between endotoxemia and vascular expression of antioxidant enzymes. Swiss albino mice (4 weeks old) were fed a high fat diet for 24 weeks and then were administered Escherichia coli endotoxin intraperitonealy, for 4 weeks. Tissue antioxidant enzymes, serum levels of IL-6 and TNF alpha were measured from the mice. We report that i.p. administration of endotoxin to hyperlipidemic mice resulted in elevation of superoxide dismutase and catalase enzymes, which was paralleled by a systemic reduction of serum cholesterol and LDL expression. Myeloperoxidase levels were also found to be elevated in aortic tissue, while an increase was also observed in the serum cytokine levels.  相似文献   
47.
虫源壳聚糖对大鼠运动能力及骨骼肌抗氧化酶系的影响   总被引:1,自引:0,他引:1  
目的:探讨补充不同浓度虫源壳聚糖对大鼠运动能力和骨骼肌抗氧化酶系的影响。方法:对大负荷游泳训练大鼠补充剂量分别为各组平均体重的0.5 g.kg-1、1.0 g.kg-1和2.0 g.kg-1的虫源壳聚糖,在8周大负荷训练结束后测定力竭游泳时间和骨骼肌抗氧化酶系的活性。结果:8周大负荷训练后,虫源壳聚糖大负荷运动组力竭游泳时间均明显长于单纯大负荷运动组,补充2.0 g.kg-1虫源壳聚糖组游泳力竭时间比单纯大负荷运动组延长了25.56%。补充虫源壳聚糖能够显著提高抗氧化酶系活性,虫源壳聚糖0.5 g.kg-1补充组与单纯大负荷运动组相比,CAT和GST酶活性显著升高(P<0.05),但SOD活性无显著差异;虫源壳聚糖1.0 g.kg-1和2.0 g.kg-1补充组与单纯大负荷运动组相比:SOD酶活性显著提高(P<0.05),CAT和GST酶活性升高极为显著(P<0.01)。MDA含量在不同水平虫源壳聚糖补充组均显著低于单纯大负荷运动组(P<0.01)。结论:补充虫源壳聚糖有助于提高训练大鼠的运动能力及骨骼肌抗氧化酶系活性。  相似文献   
48.
49.
少年在亚极量、极量负荷运动下血中MDA、GSH、SOD和CAT的变化   总被引:11,自引:0,他引:11  
为了探讨不同运动对机体自由基代谢和抗氧化酶的影响 ,采用跑台提供运动负荷 ,对 48名少年进行了安静、亚极量负荷和极量负荷下血浆中丙二醛 (MDA)、还原型谷胱甘肽 (GSH)、超氧化物歧化酶 (SOD)和过氧化氢酶 (CAT)的测定。结果发现 ,MDA在极量和亚极量运动负荷下极显著地高于安静时 ,极量负荷下又极明显地高于亚极量负荷时 ;全血中 GSH在两种负荷下均比安静时显著下降 ,但两种负荷间无明显差异 ;SOD的活力在两种负荷运动下显著高于安静状态时 ,极量负荷下虽高于亚极量负荷时 ,但无明显差异 ;CAT在亚极量负荷下其活力比安静时有所降低 ,但不显著 ,而在极量负荷下非常显著地高于安静和亚极量负荷状态时。  相似文献   
50.
Plasma levels of lipids, lipoproteins and lipid peroxides and erythrocyte Na+−K+ ATPase, Mg2+ATPase and antioxidant enzymes were measured in type-2 diabetic patients. A significant decrease in Na+-K+-ATPase activity was observed in diabetic patients which was negatively correlated with blood glucose and lipid peroxides, while the Mg2+-ATPase activity was increased. In the diabetic subjects the plasma concentrations of Na+ and K+ were increased where as erythrocyte levels of Na+ were increased and K+ were decreased. Hyperlipidaemia and increased levels of lipid peroxides were observed in the diabetic subjects. There was a significant increase in erythrocyte catalase activity in diabetics which positively correlated with their lipid peroxides. There was no change in GPx activities between controls and diabetics.  相似文献   
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