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101.
维生素E对力竭小鼠肌、脑组织自由基代谢的影响   总被引:2,自引:0,他引:2  
观察一次性力竭游泳后小鼠股四头肌、脑组织中超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量和SOD/MDA的变化情况,以及维生素E对其的影响。结果发现,力竭游泳后即刻,肌组织中SOD活性明显下降,脑组织中SOD活性、MAD含量没有明显变化;维生素E可有效抑制力竭后即刻肌组织SOD活性水平的下降。  相似文献   
102.
Fifty children (1–4 years age) presenting with microcytic hypochromic anemia (hemoglobin less than 10g/dl) were studied in two groups of 25 each. Group I was supplemented with iron (ferrous sulphate 6 mg/kg/d) while group II in addition to iron was also supplemented with vitamin A (5000 IU/d). Hemoglobin concentration was found to be significantly increased after 4 weeks of iron supplementation. Rise in hemoglobin was comparatively more in-group II, as compared to group I, after 8 and 12 weeks. Serum iron was significantly higher after 4 weeks in both the groups. Packed cell volume (PCV) and retinol levels increased significantly in-group II only. The data suggests that supplementation of vitamin A improves hematopoiesis.  相似文献   
103.
将经典维生素 B1法安息香缩合反应改进在惰性气体保护下进行,且在反应完成后加入硫代硫酸钠和锌粉抑制产物分解,可制备过去主要依赖 KCN 等剧毒催化剂合成的吸电子基团取代的苯偶姻衍生物。推测经典维生素 B1法分离不到产物,可能是由于柱层析时硅胶或氧化铝与维生素 B1分解产物的共同作用导致贫电子苯偶姻产物的分解,而 Zn-Na2 S2 O3溶液可以抑制这种作用。  相似文献   
104.
流动注射化学发光法测定维生素B6   总被引:1,自引:0,他引:1  
基于维生素B6对鲁米诺一过氧化氢化学发光反应的增敏作用,结合流动注射技术,建立了流动注射化学发光反应测定维生素B6的新方法。该方法的线性范围为5.0×10^-8~2.0×10^-6g/mL,检出限为2.3×10^-8g/mL。对5.0×10-6g/mL的维生素B6进行11次平行测定,相对标准偏差为2.8%。实验表明该方法简单、快速、灵敏。  相似文献   
105.
果蔬中维生素C测定方法的比较研究   总被引:3,自引:0,他引:3  
比较研究2,6-二氯靛酚滴定法与铁(Ⅱ)-邻二氮菲分光光度法测定果蔬中维生素C含量。样品处理后,在最佳条件下测定果蔬中的维生素C含量。滴定法在测定深色样品时欠佳;分光光度法适合于深色样品的测定,但操作繁琐。深色的样品宜选择分光光度法测其Vc含量。  相似文献   
106.
采用高压液相色谱法(HPLC)测定111份血清视黄醇。实验组和对照组分别为76.06±29.36μg/dl 和52、29±24.26μg/dl,两组差异有极显著性。用YA-Ⅱ型暗适应仪测定眼睛暗适应机能,两组分别是24.95±14.97和28.81±14.36S,这两项指标均反映出运动员机体维生素A 营养状况良好。  相似文献   
107.
Platelets play important role in precipitating ischaemic myocardial syndromes in many ways. One of the consequences of ischaemic diseases is excessive generation of oxygen derived free radicals that have numerous pathophysiological consequences. Platelet pro-oxidant enzyme, xanthine oxidase is one of the sources of generation of free radicals. In the present paper, we report the effect of administration of vitamin E along with aspirin on the levels of platelet xanthine oxidase and extent of free radical mediated damage in the patients reperfused after myocardial infarction. Our findings show that administration of 400 mg. vitamin E for six days along with 80 mg. aspirin has an excellent anti-oxidant effect as evidenced by reduced platelet xanthine oxidase activity and lowering of malondialdehdye (MDA) levels which is an index of the extent of free radical mediated damage.  相似文献   
108.
It has been suggested that antioxidant systems are impaired in pregnancy induced hypertension and hence patients are exposed to oxidative stress. In order to investigate the relationship between lipid peroxidation and certain antioxidant parameters in blood of pregnancy induced hypertension (PIH) cases, 25 normotensive and 23 PIH samples were studied. In the present study, thiobarbituric acid reactive substances showed a tendency to increase, however the increase remained statistically insignificant. Plasma ascorbic acid level remained unaltered and Vitamin E showed a tendency to increase in the study group. The findings implicate oxidative stress in the disease and cite the biochemical rationale for clinical trials of antioxidants to prevent and treat pregnancy induced hypertension.  相似文献   
109.
Lipid peroxidation product, malonaldehyde (MDA) and antioxidants were estimated in plasma and erythrocytes of 34 cases of oral submucous fibrosis (OSMF) of different grades with equal number of healthy controls to evaluate the association of reactive oxygen species (ROS) and OSMF. While plasma MDA was found to be significantly higher in patients (3.3±0.4 nmole/ml, P<0.001) as compared to controls (2.4±0.5 nmole/ml), plasma beta carotene and vitamin E levels were found to be decreased significantly in patients (81.7±14.3 μg/100 ml, P<0.001; 9.3±0.9 mg/L, P<0.01 respectively) with respect to healthy controls (110±20.8 μg/100 ml and 10.1±1.2 mg/L). The decrease in beta-carotene and vitamin E was found to be more significant in OSMF grade II and III than in grade I. After 6 weeks of oral administration of beta-carotene and vitamin E, patients showed increase in plasma level of these two antioxidants along with decrease in MDA level associated with clinical improvement.  相似文献   
110.
Folic acid and vitamin B12 are very important vitamins needed for normal cellular metabolic activities. The effects of folic acid and vitamin B12 on liver integrity of growing Wistar albino rats following therapeutic dose of phenytoin administration were investigated. The activities of serum AST, ALT, ALP were investigated. Serum total protein level and lipid profile were also measured as indices of biochemical changes. The ingestion of phenytoin alone in rats significantly reduced serum protein while AST, ALT activities incresed as compared to the control (P<0.05). Supplementation of phenytoin with oral administration of 70microgram/kg body wt of folic acid resulted in a significant reversal in serum total protein and suppression in serum AST and ALT activities. Vitamin B12 supplementation did not afford any significant protection against the effect of phenytoin ingestion but rather phenytoin toxicity was exacerbated in this study. However, the combined effects of vitamin B12 and folic acid ameliorated the effects of phenytoin on serum enzymes of experimental rats. The effect of combination of phenytoin with folic acid or folic acid and vitamin B12 is an interesting finding. Supplementation of phenytoin with folic acid or combination of these vitamins may be recommended for the purpose of ameliorating the adverse biochemical changes which are associated with phenytoin therapy. Further work is ongoing to help elucidate the effects of phenytoin and these vitamins on oxidative stress inducing mechanism.  相似文献   
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