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为了了解递增负荷运动对心电频谱分析的影响,我们采用标准12导联引导心电信号,测试了30名大学生在递增负荷运动中的心电频谱图,所测得结果提示如下:频率成分能量比W1〔W1=E(100-1000Hz)/E(0-1000Hz)〕,W2〔W2=E(80-300Hz)/E(0-1000Hz)〕,在一、二级负荷运动后增大(P＜0.05),三级负荷后恢复到安静水平。 相似文献
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Stefanie Demming Gena Peterat Andreu Llobera Hannah Schmolke Alexander Bruns Michael Kohlstedt Ala‘aldeen Al-Halhouli Claus-Peter Klages Rainer Krull Stephanus Büttgenbach 《Biomicrofluidics》2012,6(3)
This paper presents a vertically positioned microfluidic system made of poly(dimethylsiloxane) (PDMS) and glass, which can be applied as a microbubble column (μBC) for biotechnological screening in suspension. In this μBC, microbubbles are produced in a cultivation chamber through an integrated nozzle structure. Thus, homogeneous suspension of biomass is achieved in the cultivation chamber without requiring additional mixing elements. Moreover, blockage due to produced carbon dioxide by the microorganisms—a problem predominant in common, horizontally positioned microbioreactors (MBRs)—is avoided, as the gas bubbles are released by buoyancy at the upper part of the microsystem. The patterned PDMS layer is based on an optimized two-lithographic process. Since the naturally hydrophobic PDMS causes problems for the sufficient production of microbubbles, a method based on polyelectrolyte multilayers is applied in order to allow continuous hydrophilization of the already bonded PDMS-glass-system. The μBC comprises various microelements, including stabilization of temperature, control of continuous bubble formation, and two optical configurations for measurement of optical density with two different sensitivities. In addition, the simple and robust application and handling of the μBC is achieved via a custom-made modular plug-in adapter. To validate the scalability from laboratory scale to microscale, and thus to demonstrate the successful application of the μBC as a screening instrument, a batch cultivation of Saccharomyces cerevisiae is performed in the μBC and compared to shake flask cultivation. Monitoring of the biomass growth in the μBC with the integrated online analytics resulted in a specific growth rate of 0.32 h−1, which is almost identical to the one achieved in the shake flask cultivation (0.31 h−1). Therefore, the validity of the μBC as an alternative screening tool compared to other conventional laboratory scale systems in bioprocess development is proven. In addition, vertically positioned microbioreactors show high potential in comparison to conventional screening tools, since they allow for high density of integrated online analytics and therefore minimize time and cost for screening and guarantee improved control and analysis of cultivation parameters. 相似文献
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探讨黄芪总苷对运动性疲劳大鼠骨骼肌抗氧化能力、ATP酶活性及乳酸含量的影响。方法：应用力竭性游泳方法制作运动性疲劳大鼠模型,对大鼠预防性给予黄芪总苷,观察大鼠骨骼肌抗氧化能力ATP酶活性及乳酸含量的变化。结果：黄芪总苷明显提高运动性疲劳大鼠骨骼肌的POD,T-AOC和Ca^2＋Mg^2＋-ATPase的活性,降低LD的含量（P〈0.05）。结论：黄芪总苷具有保护运动性疲劳大鼠肌组织的作用,其机制可能与提高骨骼肌抗氧化能力,改善肌肉组织能量代谢有关。 相似文献
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Education and Information Technologies - Though flipped learning has positively impacted teaching English writing, its usefulness in developing students’ English writing performance,... 相似文献
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Jill?M.?AldridgeEmail author Kate?G.?Ala’i Barry?J.?Fraser 《Learning Environments Research》2016,19(1):1-15
This article reports research into associations between students’ perceptions of the school climate and self-reports of ethnic and moral identity in high schools in Western Australia. An instrument was developed to assess students’ perceptions of their school climate (as a means of monitoring and guiding schools as they are challenged to become more inclusive and grapple with increasingly diverse populations) and administered to 4067 students, 63 % of whom were aged between 12 and 17 years, in eight schools. The same students also responded to a survey developed to assess ethnic and moral identity. Analysis of the data indicated strong, positive associations between the school climate and students’ ethnic and moral identity. The results suggest that, for schools wishing to promote students’ ethnic and moral identity, it would be beneficial to consider important elements of the school climate identified in the new survey. 相似文献
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黄芪总苷对力竭运动大鼠骨骼肌中ATP酶活性的影响 总被引：1，自引：0，他引：1
目的：探讨黄芪总苷对力竭运动大鼠骨骼肌中ATP酶活性的影响。方法：对大鼠预防性给予黄芪总苷,观察力竭游泳大鼠骨骼肌ATP酶活性的变化。结果：黄芪总苷组的Na^ ＋K^＋-ATPase和Mg^2＋-AT-Pase的活性明显高于力竭运动组（p〈0.05）,黄芪总苷组的Ca^2＋-ATPase的活力虽也有一定提高,但与力竭运动组无显著性差异（p〉0.05）。结论：黄芪总苷可降低力竭运动对大鼠骨骼肌的损伤,其机制可能与提高ATP酶活性有关。 相似文献
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笔者测试分析了１０名男性大学生足球运动员在安静状态下及递增负荷运动后的高频心电图。结果提示：在三级负荷运动中高频切迹的量一双向变化过程及一、二级负荷后高频切迹数增加，而第三级负荷后又恢复到安静水平 相似文献
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主要探讨了渐进抗阻练习对大学生肌肉力量的影响。方法：健康大学生30名,采用Thera-Band渐进式弹性阻力带进行渐进抗阻练习16周,测量训练前后上、下肢的肌力。结果：30名大学生在进行渐进抗阻训练后,其肌力有显著的提高（P〈0.05）。结论：渐进抗阻练习能有效增加大学生的力量素质。 相似文献
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运用问卷调查法、数理统计法,调查、评价、分析56名高校教师有氧运动前后的情绪焦虑和睡眠质量情况.结果表明,进行有氧运动后的匹兹堡睡眠质量指数明显小于运动前(P＜0.05);进行有氧运动后高校教师的焦虑自评量表标准分均值明显小于运动前(P＜0.05).结论:有氧运动可有效缓解心理压力和焦虑情绪,调理睡眠、改善睡眠质量,是一种安全可行、积极有效的方法. 相似文献