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201.
大众健美操是一种方兴未艾的社会体育项目。受到很多人的喜爱,特别是受到中小学生的普遍欢迎。大众健美操的创编直接关系到实施的效果的好坏。在创编的过程中要根据练习对象的具体情况综合各方面的条件,选择好音乐与动作,依据大众健美操创编的原则进行创编。 相似文献
202.
M. Aglietta A. Stacchini F. Sanavio W. Piacibello 《Cellular and molecular life sciences : CMLS》1985,41(3):375-376
Summary The effect of 2 H2 receptor antagonists (ranitidine and cimetidine) on the in vitro growth of human granulomonopoietic precursors (CFU-GM) was studied. Ranitidine, although having an anti H2 receptor activity much greater than that of cimetidine, displays the same toxicity for CFU-GM.Acknowledgments. This work was supported by CNR, Rome, PFCCN and AIRC, Milan. 相似文献
203.
Dealing with coercion: Critical Systems Heuristics and beyond 总被引:1,自引:1,他引:0
Gerald Midgley 《Systemic Practice and Action Research》1997,10(1):37-57
This paper begins with an introduction to the philosophy and methodology of Critical Systems Heuristics (CSH). Following this,
various citicisms of CSH are reviewed. One particularly important criticism is that CSH should not be seen as a replacement
for other systems approaches, but as complementary to them. It is this idea of complementarity that has led several Critical
Systems thinkers to take CSH, along with a number of other systems methods, and try to show that they are most appropriately
used in different contexts. CSH, it is said, is at its most useful when we are confronted with coercive situations. However,
in this paper it is argued that coercion is usually characterised by closure of debate. Therefore CSH, which depends upon
the possibility of communication (or arbitration) between stakeholder groups, becomes redundant when coercion is experienced.
It is further argued that coercion can only be addressed adequately by widening our definition of systems practice to include
campaigning and direct political action. There is still considerable scope for developing these areas in the systems domain. 相似文献
204.
杨思娅 《曲靖师范学院学报》2002,(6)
以实验获得的对称二氨基二醇硼催化体结构为初始构型 ,采用量子化学AM1MO方法对几种硼催化体进行了优化 ,计算了各配位催化体的相对能和电荷 .根据计算得出的结果 ,分析了硼催化体结构与催化活性的关系 ,得出了和实验相一致的结果 相似文献
205.
本工作研究了几种不同浓度的川芎嗪、丹参对豚鼠输尿管电位的影响。用0.5mg/ml、1.0mg/ml、2.0mg/ml、4.0mg/ml的川芎嗪静脉注入均对豚鼠的输尿管电位有抑制作用,其中2.0mg/ml。4.0mg/ml的影响较明显。用1:80、1:20、1:10的丹参注射液静脉注入对豚鼠的输尿管电位也同样有抑制作用。 这些结果表明,丹参具扩张小动脉的作用,川芎嗪、丹参对输尿管平滑肌起ca~(2+)拮抗剂作用。 相似文献
206.
神经营养素是一类神经营养因子,目前已被用于神经萎缩、神经变性、外伤修复等疾病的治疗中.它的研究极大地推动了神经生物学和细胞生物学的发展,本文拟就神经营养素的生物学作用及临床应用前景作一简要的介绍. 相似文献
207.
YANG XinLin CHEN Zhe MENG XianMei LI Bo TAN Xin 《科学通报(英文版)》2007,52(13):1802-1806
Activities of trimalonic acid fullerene (TMA C_60) on DNA restrictive enzymatic reaction were investigated by using two restrictive endonucleases Hind III and EcoR I and plasmid pEGFP-N1 with single restric-tive site for both enzymes. Meanwhile, TMA C60 was also tested to clarify its effects on polymerase chain reaction (PCR) with the catalyst of Taq DNA polymerase and the template of plasmid pEGFP-N1. The products from restrictive reactions or PCR were detected by agarose gel electrophoresis. It was found that the product amounts from restrictive reactions or PCR decreased significantly with addition of TMA C60. The inhibition by TMA C60 was dose-dependent and IC50 values for reactions of Hind III, EcoR I and PCR were 16.3, 6.0 and 6.0 μmol/L, respectively. Addition of two scavengers of reactive oxygen species (ROS), L-ascorbic acid-2-phosphate ester magnesium and sodium azide at the con-centrations of 2―10 mmol/L did not antagonize the activities of TMA C60 against PCR and two restrictive reactions. However, increase of Taq DNA polymerase amounts in PCR system antagonized the activities of TMA C60. These data implied that TMA C60 was able to inhibit the activities of the three above-mentioned enzymes involved in DNA metabolism, and that this inhibition probably did not correlate to ROS. 相似文献
208.
209.
从代理权授予行为的理论源流出发,讨论代理权授予的独立性与无因性;代理权的授予与委托合同及代理行为的关系;委托代理权的授予行为弊端及其法律后果。 相似文献
210.
C. Jotin Khisty 《Systemic Practice and Action Research》2006,19(4):295-307
This paper is written for a broad general readership. It presents a prismatic reflection on systemic thinking, Buddhist philosophy, and deep ecology, with the objective of shedding light on world problems and understanding their gravity. Such an inquiry constitutes a formidable spearhead for the betterment of the world, guiding us towards holism, and moving us away from the partial, fragmented, compartmentalized thinking that is prevalent today. Although no deliberate attempt is made to articulate solutions to specific problems, a brief account of current socially engaged action is described. 相似文献