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排序方式: 共有1303条查询结果,搜索用时 77 毫秒
1.
Tasuku Ogita Rosaly Vallejo Manaois Manabu Wakagi Tomoyuki Oki Yuko Takano Ishikawa 《International journal of food sciences and nutrition》2016,67(4):431-440
Two cultivars of Japanese parsley were harvested in different seasons; their antioxidant capacities were evaluated by oxygen radical absorbance capacity (ORAC) methods, and the contents of hydrophilic and lipophilic antioxidants were compared. Japanese parsley possessed potent antioxidant capacities both in hydrophilic and lipophilic extracts when evaluated by ORAC methods. LC/MS/MS analyses revealed that chlorogenic acid and four kinds of quercetin glycosides were major antioxidants in the hydrophilic extract. Lutein was the main contributor to the antioxidant capacity of the lipophilic extract. Antioxidant capacities of the hydrophilic extracts of both cultivars tended to be higher in winter because of the increase in the contents of chlorogenic acid and quercetin glycosides. An obvious trend in the lipophilic antioxidant capacities or lutein contents was not observed irrespective of the cultivar. 相似文献
2.
白癜风与氧化-抗氧化失衡 总被引:1,自引:0,他引:1
白癜风是一种较常见的色素脱失性疾病,临床上以表皮黑素细胞破坏缺失而出现色素脱失斑为主要特征,严重影响患者的外观美容。白癜风的病因学分子机制目前尚无定论,存在多种假说。近年来,对白癜风患者机体抗氧化水平的研究日益增多,越来越多证据提示,机体氧化-抗氧化平衡失调,导致局部微环境中活性自由基大量聚集,引起氧化应激,造成细胞损伤,是引起白癜风发病的一个重要因素。 相似文献
3.
P. Venditti M. C. Piro G. Artiaco S. Di Meo 《European journal of applied physiology》1996,74(4):322-329
We studied the changes in the anti-oxidant capacity of tissues, such as heart, liver, and blood in male and female rats, as a parameter for evaluating oxidative stress after either a prolonged (210 min) or an exhausting bout of swimming. Furthermore, we also investigated exercise-induced changes in the electrophysiological properties, measured in vitro, of papillary muscle fibres. Small decreases of anti-oxidant capacities after prolonged exercise [0.10 (SEM 0.04) in heart, 0.43 (SEM 0.19) in liver, 0.22 (SEM 0.05) in blood] and greater decreases after exhausting exercise [0.23 (SEM 0.04) in heart, 0.90 (SEM 0.29) in liver, 0.34 (SEM 0.04) in blood] were found in tissues from the male rats. For the female rats, similar changes were found only in the blood [0.11 (SEM 0.07) and 0.35 (SEM 0.06) for prolonged and exhausting exercise, respectively]. Liver and heart anti-oxidant capacity remained unchanged after prolonged exercise, while after exhausting swimming it underwent a decrease almost the same as found in the male rats, though the swimming time to exhaustion (endurance capacity) was much greater [706 (SEM 10) min and 444 (SEM 32) min for the females and males, respectively]. The duration of the action potential, recorded from papillary muscle fibres, underwent changes related to the decreases in heart anti-oxidant capacity. In fact, the action potential duration (APD) was shorter only in preparations from the male rats after prolonged exercise, but in all preparations after exhausting exercise. After such exercise, the APD was similar for the male and female rats [37.1 (SEM 3.4) ms and 37.0 (SEM 3.6) ms, respectively]. Such a pattern was independent of stimulation frequency, since it was found substantially unchanged when the frequency was increased from 1 to 5 Hz. We concluded that the different susceptibilities to the effects of physical exercise, exhibited by tissues from these male and female rats might have been related to different capacities to oppose oxidative stress effectively. 相似文献
4.
自由基清除酶(剂)对SMAO休克大鼠保护作用的研究 总被引:1,自引:0,他引:1
夹闭大鼠肠系膜上动脉1h后松夹,于松夹前分别给予超氧化物歧化酶(superoxide dismutasv, SOD)、过氧化氢酶(catalase, CAT)、别嘌呤醇(allopurinol, ALLO)、SOD+CAT、SOD+ALLO和SOD+CAT+ALLO。结果表明,除单用CAT外,其他单用或伍用自由基清除酶(剂)均有抗脂质过氧化损伤效应,表现为应用自由基清除酶(剂)能明显抑制肠、心、肝、肺组织中丙二醛(malodialdehyde, MDA)含量的升高,稳定组织内源性SOD的活力,同时血浆溶酶休酶的释放减少,休克动物血压升高,死亡率下降,平均存活时间明显延长。实验结果尚表明,应用自由基清除酶(剂)可以明显减轻肠系膜上动脉夹闭(superior mcsenteric artery occlusion, SMAO)休克大鼠小肠粘膜的病理改变。 相似文献
5.
Interaction of family history of breast cancer and dietary antioxidants with breast cancer risk (New York,United States) 总被引:1,自引:0,他引:1
Christine B. Ambrosone James R. Marshall John E. Vena Rosemary Laughlin Saxon Graham Takuma Nemoto Jo L. Freudenheim 《Cancer causes & control : CCC》1995,6(5):407-415
We sought to determine if specific dietary antioxidants may be particularly effective in reducing breast cancer risk for women reporting family history (FH) of breast cancer in a first-degree relative. Interviews regarding usual diet, health, and family histories were conducted with 262 premenopausal and 371 postmenopausal women with incident, primary breast cancer from western New York (United States). These women were frequencymatched by age and county of residence with community controls. Among premenopausal women, there was a significant interaction between FH and -tocopherol; -tocopherol was associated with significantly decreased risk among FH+ women (adjusted fourth-quartile odds ratio [OR]=0.01, 95 percent confidence interval [CI]=0.0–0.3). This association was much weaker for FH-women [OR=0.7, CI=0.4–1.2]. For FH-women, a significant inverse association was observed between -carotene and premenopausal breast-cancer risk (OR=0.4, CI=0.3–0.5), but not for FH+ women (OR=0.5, CI=0.1–4.0). Similar relationships, although not as strong, were noted among postmenopausal women. Although limited by small numbers, these results suggest that biologic mechanisms of tumorigenesis may differ in FH+ and FH-women, and that -tocopherol may be a potential chemopreventive agent for women with a family history of breast cancer, particularly premenopausal women.This research was conducted by the Department of Social and preventive Medicine, State University of New York at Buffalo. This publication is supported in part by grants CA11535 and 5 R25 CA1820117 from the US National Cancer Institute and PDT-434 from the American Cancer Society. Dr Freudenheim is a recipient of a Research Career Development Award from the National Cancer Institute (CA01633). This work is solely the responsibility of the authors and does not necessarily represent the views of the NCI. 相似文献
6.
M. Ristola E. Savilahti M. Leirisalo-Repo H. Repo 《European journal of pediatrics》1991,150(3):173-178
Neutrophils purified from peripheral blood of patients with the Shwachman syndrome show enhanced chemiluminescence (CL) and depressed chemotaxis. Here we present data showing that the increased CL response can be demonstrated by using a whole blood CL assay. This assay is well-suited for studies in infants, because the blood sample volumes needed are small. Increase in CL was most distinct in the initial (1 min) activation induced by N-formyl-methionyl-leucyl-phenylalanine. The 1-min response is considered to derive from extracellular production of oxygen radicals. Such an extracellular oxygen radical production may render the patients susceptible to undue oxidant stress. We therefore treated the patients with two antioxidants, thiamine and -tocopherol, for 3 months. This supplementation, however, failed to exert any significant effect on either whole blood CL or migration of the patients' neutrophils under agarose. 相似文献
7.
Prophylaxis against lipopolysaccharide-induced liver injuries by lipoic acid in rats 总被引:1,自引:0,他引:1
Lipopolysaccharide (LPS) is a major cell wall molecule of Gram-negative bacteria known to stimulate the synthesis and secretion of several metabolites, such as reactive oxygen species, from phagocytes that play an important role in the pathogenesis of tissue injuries. In this study, the prophylactic effect of the antioxidant lipoic acid was evaluated in an animal acute organ injury model. Animals were pre-treated intraperitoneally with lipoic acid (50 mg kg(-1) body weight) or saline; 3 h later, pretreated animals were challenged intravenously with LPS (Escherichia coli 0111:B4, 1.0 mg kg(-1) body weight) or saline and killed 21 h later. Saline-pretreated animals challenged with LPS were extensively damaged in the liver, as evidenced by an increase in plasma alanine and aspartate aminotransferase activities. Also, LPS injection to saline-pretreated animals resulted in significant increases in plasma tumour necrosis factor-alpha (TNFalpha) and nitric oxide (NO) concentrations, suggestive of activation of the proinflammatory response. The LPS challenge to saline-pretreated animals also increased hepatic myeloperoxidase activity as well as protease and chloramine levels, suggestive of neutrophil infiltration and activation of the inflammatory response. In addition, the involvement of oxidative stress was evident, because a significant increase in lipid peroxidation was observed in the livers of saline-pretreated animals challenged with LPS. The administration of lipoic acid prior to LPS challenge resulted in a significant alleviation of liver injuries, evidenced by a general reversal of the altered biochemical indices toward normal among treated animals. These results indicate that lipoic acid may serve as a potentially effective prophylactic pharmacological agent in alleviating LPS-induced tissue injuries. 相似文献
8.
"调肝颗粒剂"阻断肝癌前病变过程中的抗氧化和清除自由基作用 总被引:7,自引:0,他引:7
目的探讨氧自由基与肝细胞癌变的关系,以及调肝颗粒剂的抗氧化作用.方法:用二乙基亚硝胺(DEN)建立SoltFarber二步肝癌前病变短期动物模型,用调肝颗粒剂进行干预,电子自旋共振(ESR)技术测定羟自由基清除率,改良的硫代巴比土酸(TBA)法测定过氧化脂质(LPO),用双硫代硝基苯(DTNB)直接显色法测定谷胱甘肽过氧化物酶(GSH-Px),用黄嘌呤-黄嘌呤氧化酶法测定超氧化物歧化酶(SOD).结果:调肝颗粒剂能明显抑制肝癌前病变过程中产生的丙二醛(MDA),并对羟自由基具有良好的清除作用.与此同时提高肝组织及血浆中的SOD、GSH-Px活力.结论:调肝颗粒剂可以通过抗氧化来干预、阻断肝癌前病变. 相似文献
9.
Bickford PC Gould T Briederick L Chadman K Pollock A Young D Shukitt-Hale B Joseph J 《Brain research》2000,866(1-2):211-217
The free radical theory of aging predicts that reactive oxygen species are involved in the decline in function associated with aging. The present paper reports that diets supplemented with either spinach, strawberries or blueberries, nutritional sources of antioxidants, reverse age-induced declines in beta-adrenergic receptor function in cerebellar Purkinje neurons measured using electrophysiological techniques. In addition the spinach diet improved learning on a runway motor task, previously shown to be modulated by cerebellar norepinephrine. Motor learning is important for adaptation to changes in the environment and is thus critical for rehabilitation following stroke, spinal cord injury, and the onset of some neurodegenerative diseases. These data are the first to indicate that age-related deficits in motor learning and memory can be reversed with nutritional interventions. 相似文献
10.
Jung Sook Seo Kyung Mi Yang Jung Mi Kim Hyesun Min Chang Su Kim Betty J. Burri 《Nutrition Research》2004,24(12):959-968
This human study was conducted to evaluate the effect of chronic alcohol consumption on plasma concentrations of lipid and the antioxidative system in 44 Korean alcoholics and 45 age-, sex-, and nationality-matched nonalcoholic subjects. Plasma triacylglycerols and atherogenic index were higher in alcoholics than in control subjects. Plasma total cholesterol was not different among groups, but plasma high-density lipoprotein cholesterol was lower in alcoholics. There were positive correlations between ethanol consumption and plasma lipid peroxide and atherogenic index in all subjects; there were negative correlations between ethanol consumption and plasma high-density lipoprotein cholesterol in all subjects. There were no significant differences between alcoholics and control subjects in plasma concentrations of α-tocopherol, although plasma α-tocopherol/lipid tended to be lower in alcoholics. Plasma retinol was lower in alcoholics. These results suggest that chronic ethanol consumption can contribute to increased risk for vascular diseases in Korean alcoholics. 相似文献