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31.
氧自由基代谢中微量元素的作用机制 总被引:1,自引:0,他引:1
梅光泉 《襄樊职业技术学院学报》2004,3(1):1-3
对铜锌超氧化物歧化酶、锰超氧化物歧化酶和铁超氧化物歧化酶等三种金属蛋白酶的活性结构及酶蛋白中金属离子催化氧自由基的机理进行了综述。 相似文献
32.
艺术法不是一部单行法规,而是相关法规的总称。由于艺术的外延很大,其所涉及的社会关系也是多种多样,而不仅仅是有关版权的问题,因此,有必要从宏观上把握艺术发生过程中所涉及的一些重要关系。 相似文献
33.
Jon Bruschke Andrew Gonis III Sarah A. Hill Pam Fiber-Ostrow William Loges 《Communication monographs》2016,83(4):521-534
Prior research on pretrial publicity has produced mixed results and a roughly equal number of studies show an effect, show no effect, or show mixed results. We explored the effects of (a) homogenous vs. heterogeneous exposure (whether deliberating jurors were all exposed to the same publicity or not) and (b) pre-deliberation queries as potential contributors to mixed results. We found an effect for positive but not negative publicity on conviction rates but not evidence ratings. Exposure heterogeneity appears to explain these differences and pre-deliberation queries did appear to play some role in the obtained outcomes. Overall these findings do not replicate a robust publicity effect and future research should consider how homogeneous exposure and pre-deliberation opinion queries influence results. 相似文献
34.
Fabio De Siati Guillaume Laffaye Giorgio Gatta Antonio Dello Iacono Johnny Padulo 《Journal of sports sciences》2016,34(15):1466-1472
Testing is one of the important tasks in any multi-step sport programme. In most ball games, coaches assess motor, physical and technical skills on a regular basis in early stages of talent identification in order to further athletes’ development. The purpose of the study was to investigate anthropometric variables and vertical jump heights as a free throw effectiveness predictor in water-polo players of different age groups. Two hundred and thirty-six young (10–18 years) male water-polo players partitioned into three age groups underwent anthropometric variables’ measures and squat- and countermovement-jump tests, and performed water-polo free throws. Anthropometric variables, vertical jump heights and throw speed – as a proxy for free throw effectiveness – resulted different over age groups. Particularly, throw speed changed from 9.28 to 13.70 m · s?1 (+48%) from younger to older players. A multiple-regression model indicated that body height, squat-jump height and throw time together explain 52% of variance of throw speed. In conclusion, tall height, high lower limb power and throwing quickness appeared to be relevant determinants for effective free throws. Such indications can help coaches during talent identification and development processes, even by means of novel training strategies. Further research is needed over different maturity statuses. 相似文献
35.
Daniel Link Otto Kolbinger Hendrik Weber Michael Stöckl 《Journal of sports sciences》2016,34(24):2312-2320
ABSTRACTThis study investigates the spatial relationship of performance variables for soccer free kicks. In order to suggest ways in which players might optimise their performance, we collected data from free kicks (<35 m to goal line) of two German Bundesliga seasons (2013/14, 2014/15) (n = 1624). In the analysis, we applied the ISO-map approach using colour gradients to visualise the mean values of a variable on a 2D-map of the pitch. Additionally, variograms were used to describe the degree of spatial dependence of the free kick variables. Results show that DENSITY, TYPE OF PLAY, PLAYERS IN WALL, DISTANCE TO WALL and RULE VIOLATION were strongly spatially dependent. Centrality and proximity to the goal increased the variables PLAYERS IN WALL, RULE VIOLATIONS and INTERRUPTION TIME, and the ratio of goals scored increased from 5.9% (central far) to 10.9% (central near). In 70.9% of the shots, players preferred a switched laterality, which did not result in a higher success rate. Furthermore, there was no statistical advantage for the defensive team when DISTANCE TO WALL was below 9.15 m or when there was a RULE VIOLATION. Crosses had a success rate (i.e., first controlled ball contact after the cross) of 20.8%. Played with natural laterality, they were 5% more successful than with switched laterality. Crosses from the right side outside the penalty box were 10% more successful than from the left side. Therefore, it might be worthwhile practising the defence of balls coming from this side. 相似文献
36.
目的:探索健身气功·八段锦(竞赛功法)对大学生机体自由基代谢和身体形态的影响。方法:主要采用实验法,随机抽取2014级康保系男生和女生各20人,持续进行4个月的功法习练,观察血脂和生理机能的变化。结果:大学生经过4个月的功法习练后,3个时间点测试SOD、CAT和大腿围指标呈上升趋势,MDA、XOD和腰臀比指标呈下降趋势,差异具有统计学意义;测试体重、体重指数和大臂围3项指标没有显著性差异。结论:健身气功·八段锦(竞赛功法)对大学生机体脏腑、固肾壮腰、提振精神、防治疲劳、改善血液循环、提高腰腹柔韧和腿部力量等方面有重要帮助。 相似文献
37.
荧光法测定羟基自由基及中草药抗氧化性 总被引:1,自引:0,他引:1
L-苯丙氨酸本身具有较弱的荧光,在羟基自由基的作用下能产生较强的荧光,其激发波长和发射波长分别是277 nm和306 nm.很多中草药提取物可以清除溶液中的羟基自由基,从而使溶液的荧光增强程度降低.据此,建立了一种测定中草药抗氧化性的方法.研究了L-苯丙氨酸-Fe2 -H2O2体系产生羟基自由基的最佳条件,并测试了赤芍、钩藤、姜黄、炒蒺藜四种中草药水提物的抗氧化活性. 相似文献
38.
《说文解字》的“心”部字在一定程度上反映了汉民族的思想文化传统。通过对“心”与思维、情感的关系以及古代哲学对“心”认识的阐释,我们可以管窥中华思想的独特性与传承性。 相似文献
39.
在市场经济条件下,人的个性和自由得到了一定程度的张扬,怎样处理和理解好集体主义和个人主义的关系。如何在加强集体主义的同时兼顾个人的自由发展,本文就此问题作了一些探讨。 相似文献
40.
曾祥旭 《南阳师范学院学报》2004,3(5):114-116
庄子的“吾丧我”涵盖工夫与本体两个层面,其含义是“唯丧我才能见道”,又是“见道后的自然解脱”。庄子“大木”的形象是丑的,但“大木”意象是美的,“大木”的本质是庄子对个体生死意义的独到领悟,又是一种超然而可求的人生态度。 相似文献