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121.
对高水平竞技体育训练的适应机制及其主要观点的思考 总被引:4,自引:0,他引:4
乌尔里希·哈特曼 《首都体育学院学报》2004,16(4):1-2
本文作者认为中国体能类项目落后的主要原因不在于“遗传、训练条件和训练的具体手段”等问题,而是缺乏科学训练的理念,在训练方向和指导思想方面没有跟上世界的发展。本文着重阐述了运动训练的生化基础,强调了训练必须遵循生物适应的原则,提出“最大的训练负荷并不能获得最佳的适应,适应的‘最佳’区域肯定位于运动员可承受负荷之下” 相似文献
122.
目的:探讨绵地花菌黄酮类化合物的抗氧化活性。方法:采用有机溶剂萃取的方法,获取绵地花菌子实体黄酮类化合物,以VC作为对照,测定清除DPPH·、羟基自由基、亚硝酸盐、超氧阴离子的能力等指标。结果:绵地花菌黄酮类化合物能有效的清除DPPH·、羟自由基、亚硝酸盐和超氧阴离子,其清除能力的大小与浓度呈正相关。结论:绵地花菌黄酮类化合物具有较强的体外抗氧化活性。 相似文献
123.
Yun Xing Le Cai Tian-peng Yin Yang Chen Jing Yu Ya-rong Wang Zhong-tao Ding 《Journal of Zhejiang University. Science. B》2016,17(5):391-398
The antioxidant activities and total phenolic content of fermented Salvia miltiorrhiza with fungus Geomyces luteus were investigated. The results revealed that G. luteus fermentation could significantly improve the antioxidant activity and total phenolic content of S. miltiorrhiza. The main antioxidant constituents were characterized by spectroscopic analysis as salvianolic acids. High-performance liquid chromatography (HPLC) quantification also showed the enhanced content of salvianolic acid B after fermentation. The present study suggests that G. luteus fermentations are effective in the S. miltiorrhiza salvianolic acids’ enrichment process. 相似文献
124.
Martha N. Ovando 《Journal of Personnel Evaluation in Education》2005,18(3):171-183
The aim of this action research study was to enhance the instructional leadership capacity of aspiring school leaders, through a practical learning experience. The participants observed classes, collected classroom-based data, prepared and delivered written constructive feedback to teachers. Findings suggest that aspiring school leaders need to develop a knowledge foundation related to quality instruction, teachers respond in a positive way and appreciate the feedback offered, constructive feedback has potential to guide teachers’ professional development, aspiring instructional leaders must be professional as they deliver feedback, and schools need to set up system for the effective delivery of constructive feedback to teachers so that teaching and learning excellence can be achieved. 相似文献
125.
In order to investigate the antioxidant properties of the polysaccharides from the brown alga Sargassum fusiforme, the crude polysaccharides from S.fusiforme (SFPS) were extracted in hot water, and the lipid peroxidation inhibition assay exhibited that SFPS possessed a potential antioxidant activity. Hence, two purely polymeric fractions, SFPS-1 and SFPS-2 were isolated by the column of DEAE (2-diethylaminoethanol)-Sepharose Fast Flow, with their molecular weights of 51.4 and 30.3 kDa determined by high performance gel permeation chromatography (HPGPC). They were preliminarily characterized using chemical analysis in combination of infrared (IR) and nuclear magnetic resonance (NMR) spectroscopies and found to contain large amounts of uronic acids and β-glycosidical linkages. The antioxidant activities of these two SFPS fractions were evaluated using superoxide and hydroxyl radical-scavenging assays. The results show that the antioxidant ability of SFPS-2 was higher than that of SFPS-1, probably correlating with the molecular weight and uronic acid content. 相似文献
126.
KARTHIKEYAN B. JALEEL C.A. GOPI R. DEIVEEKASUNDARAM M. 《Journal of Zhejiang University. Science. B》2007,8(7)
An experiment was conducted on Catharanthus roseus to study the effect of seed treatments with native diazotrophs on its seedling growth and antioxidant enzyme activities. The treatments had significant influence on various seedling parameters.There is no significant influence on dry matter production with the diazotrophs, Azospirillum and Azotobacter. However, the vital seedling parameters such as germination percentage and vigour index were improved. Azotobacter treatment influenced maximum of 50% germination, whereas Azospirillum and Azotobacter were on par with C. roseus with respect to their vigour index. There was significant difference in the population of total diazotrophs. Azospirillum and Azotobacter between rhizosphere and non-rhizosphere soils of C. roseus had the same trend and were observed at various locations of the study. The activities of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT) were increased to a significant extent due to the treatment with diazotrophs. 相似文献
127.
Fernanda Rafaela JARDIM Fhelipe Jolner Souza de ALMEIDA Matheus Dargesso LUCKACHAKI Marcos Roberto de OLIVEIRA 《Journal of Zhejiang University. Science. B》2020,21(4):263-279
有机硫化物萝卜硫烷(SFN)是一种有效的细胞保护剂,在体外和体内实验模型中均可促进抗氧化、抗炎、抗糖化和抗菌作用。因为氧化磷酸化系统的存在,所以线粒体是三磷酸腺苷(ATP)的主要产生部位。同时,线粒体也是具核人体细胞中产生活性氧的主要场所。线粒体损伤在多种人类疾病中起着重要作用,包括神经退行性病变和代谢异常。本文描述和讨论了SFN调节哺乳动物细胞中线粒体功能和动力学的作用和机理,以及其对肿瘤细胞中线粒体促凋亡途径的促进作用。SFN对线粒体的调节作用使得它在一定程度上被认为是一种细胞保护剂。本文还指出了几个需要通过进一步实验解决的问题,即未来的可能研究方向,这可能会对该领域的研究人员具有指导作用。 相似文献
128.
Shivkumar Chauhan Nirmalendu Nath Vinay Tule 《Indian journal of clinical biochemistry : IJCB》2008,23(3):238-242
Picrorhiza kurrooa is mentioned in Ayurveda for the treatment of many disorders, but it has not been subjected to systematic
scientific investigations to assess its antidiabetic effect. The oral administration of aqueous and methanol extracts of P.
kurrooa rhizomes (250 and 500 mg / kg body weight / day) for 15 days significantly reduced blood glucose, glycosylated haemoglobin
and increased total hemoglobin, plasma insulin in alloxan-induced diabetes in albino rats. The treatment also showed significant
correction in the level of nitric oxide radicals, superoxide radicals, peroxynitrite radical, lipid peroxidation, glutathione,
glutathione reductase, glutathione-S-transferase, glutathione peroxidase, superoxide dismutase and catalase in the pancreas
of alloxan diabetic rats. 相似文献
129.
柠檬酸改性竹屑吸附亚甲基蓝的动力学和热力学分析 总被引:1,自引:0,他引:1
为拓宽竹材剩余物的开发应用新途径。以竹屑为原料,柠檬酸为改性剂,制备了柠檬酸改性竹屑吸附剂,以亚甲基蓝(MB)为吸附对象,考察了pH、时间、吸附剂投量及吸附温度等对吸附剂吸附MB效果的影响,并对其吸附动力学和热力学进行了分析。结果表明:溶液pH增大,吸附剂对MB的吸附量增大,pH在5-9间变动,吸附剂对MB吸附量变化不大;染料初始浓度和吸附温度增加,吸附剂对MB吸附能力增强;在吸附120min,吸附达到平衡,吸附动力学过程符合二级动力学模型,吸附热力学过程符合Langmuir模型;在25℃、35℃、45℃时,吸附剂对MB的最大吸附量分别为106.38 mg/g、121.95 mg/g和125mg/g;竹屑吸附剂对MB的吸附过程是一个吸热的自发过程。 相似文献
130.