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31.
马克思的物质变换裂缝理论分析和批判了资本主义制度下人与土地之间的异化关系,从制度和生产方式层面提出了消除物质变换裂缝现象的根本途径。深刻领会马克思物质变换断裂理论的内涵,有利于我们正确处理现阶段比较突出的人地矛盾,对于贯彻落实科学发展观和建设社会主义生态文明,无疑具有重大的现实意义。 相似文献
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Michael A. Christmass Susan E. Richmond Nigel T. Cable Peter G. Arthur Peter E. Hartmann 《Journal of sports sciences》2013,31(8):739-747
The aim of this study was to determine exercise intensity and metabolic response during singles tennis play. Techniques for assessment of exercise intensity were studied on-court and in the laboratory. The on-court study required eight State-level tennis players to complete a competitive singles tennis match. During the laboratory study, a separate group of seven male subjects performed an intermittent and a continuous treadmill run. During tennis play, heart rate (HR) and relative exercise intensity (72 ± 1.9% V O 2m ax ; estimated from measurement of heart rate) remained constant (83.4 ± 0.9% HR m ax ; mean s x ) after the second change of end. The peak value for estimated play intensity (1.25 ± 0.11 steps . s -1 ; from video analysis) occurred after the fourth change of end (P < 0.005). Plasma lactate concentration, measured at rest and at the change of ends, increased 175% from 2.13 ± 0.32 mmol . l -1 at rest to a peak 5.86 ± 1.33 mmol . l -1 after the sixth change of end (P < 0.001). A linear regression model, which included significant terms for %HR m ax (P < 0.001) and subject (P < 0.001), as well as a %HR max subject interaction (P < 0.05), accounted for 82% of the variation in plasma lactate concentration. During intermittent laboratory treadmill running, % V O 2peak estimated from heart rate was 17% higher than the value derived from the measured V O 2 (79.7 ± 2.2% and 69.0 ± 2.5% V O 2peak respectively; P < 0.001). The % V O 2peak was estimated with reasonable accuracy during continuous treadmill running (5% error). We conclude that changes in exercise intensity based on measurements of heart rate and a time-motion analysis of court movement patterns explain the variation in lactate concentration observed during singles tennis, and that measuring heart rate during play, in association with preliminary fitness tests to estimate V O 2 , will overestimate the aerobic response. (P < 0.001), estimated play intensity 相似文献
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对优秀运动员以补充肌酸来提高运动成绩的探讨 总被引：4，自引：0，他引：4
近几年来,运动员补充肌酸(Cr)已经非常普遍。不少研究表明补充肌酸有潜在性的促力效果,其机制是:补充的肌酸增加了肌肉中肌酸和磷酸肌酸的浓度,引起三磷酸腺苷(ATP)合成率增加,延缓疲劳发生,且在大强度重复练习中促进恢复。本文通过研究发现这些促力效果都是在实验室条件下,由非运动员受试者完成几组练习后得出的。而优秀运动员完成大强度练习或比赛时的数据则表明:他们并没有从肌酸的补充中受益。 相似文献
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Ananth N. Rao Rajesh B. Iyer J. Kavitha Minakshi Koch Kumar V. Suresh 《Indian journal of clinical biochemistry : IJCB》2008,23(4):407-409
Defects in biotin metabolism are mainly associated with either the enzyme Biotinidase or Holocarboxylase synthetase. Defects
in either enzymes depletes biotin utilization by the cells. Holocarboxylase synthetase deficiency is an inherited disorder
in which the body is unable to use the vitamin biotin effectively. This condition is inherited in an autosomal recessive pattern.
We present a case of a 9 year old girl with atypical symptomology as a case holocarboxylase synthetase deficiency, who demonstrated
an increased excretion of propionic and methyl malonic acids, with her biotinidase activity being normal. She demonstrated
remarkable improvement on biotin supplementation. 相似文献
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Ryan S. Sacko Danielle Nesbitt Kerry McIver Ali Brian Farid Bardid David F. Stodden 《Journal of sports sciences》2019,37(15):1755-1761
Objective: To examine children’s energy expenditure (EE) during object projection skill performance at three intensity intervals. Methods: Children’s (42, Mage = 8.1) average metabolic equivalents of task (METs) were calculated using a COSMED K4b2 while they repeatedly performed blocks of kicking, throwing (overhand), and striking (two-handed) during 6, 12, and 30-s interval conditions. A repeated-measures analysis of covariance examined differences in METs while controlling for skill level. Results: Data indicated a main effect for interval condition (df = 2, 123, F = 94.36, p <.001, η2 = .605). Post hoc t-tests demonstrated decreasing performance interval times yielded progressively higher METs (p <.001) across the three conditions (30s = 4.5±0.8 METs, 12s = 6.3±1.3, 6s = 8.3±1.6). There also was a main effect for sex (df = 1,120, F = 52.28, p <.001 η2 = .305). Boys demonstrated higher METs at each performance interval (p <.001). Conclusion: Skill practice with a maximum of one trial every 30s resulted in the equivalent of at least moderate physical activity (>4.0 METs) and intervals of 6s demonstrated vigorous physical activity (>7.0 METs). Practicing/performing object projection skills, even at intervals that allow for adequate instruction and feedback (i.e., 1 trial/30s), promotes MVPA in children. 相似文献
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运动与营养对自由基代谢的影响 总被引：1，自引：0，他引：1
本文综述了运动和营养对自由基代谢的影响.运动可使自由基的产生增多,运动训练和营养补充能提高机体清除自由基的能力,减少脂质过氧化,增强抗氧化酶的活力及提高运动耐力. 相似文献
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The concept of anaerobic ammonium oxidation (ANAMMOX) is presently of great interest. The functional bacteria belonging to
the Planctomycete phylum and their metabolism are investigated by microbiologists. Meanwhile, the ANAMMOX is equally valuable
in treatment of ammonium-rich wastewaters. Related processes including partial nitritation-ANAMMOX and completely autotrophic
nitrogen removal over nitrite (CANON) have been developed, and lab-scale experiments proved that both processes were quite
feasible in engineering with appropriate control. Successful full-scale practice in the Netherlands will accelerate application
of the process in future. This review introduces the microbiology and more focuses on application of the ANAMMOX process.
Project supported by the National Hi-Tech Research and Development Program (863) of China (No. 2006AA06Z332), and the Science
and Technology Foundation for Key Project of Zhejiang Province (No. 2003C13005), China 相似文献
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A research group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol-a chemical found in the skins of red grapes in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said. 相似文献