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301.
根据眼球的三维静力学模型与眼球运动的三维动力学模型建立的非线性方程组所求得的结果,利用Visual C^ 编程语言初步建立了眼球的三维立体模型,并设计了眼球运动的动画程度,介绍了程序各个组成模块的主要属性和主要功能,给出了程序设计过程所用到的坐标系统设定方式、控制界面的主要功能和动画实现的主要过程。 相似文献
302.
Sports compression garments are common-selected sportswear to improve athletic performance and reduce sports injury. Since they consist of elastic textile that exerts compression and pressure onto the muscle,muscle activation is of interest to sports compression garment manufactures who seek to enhance sports performance through gradient compression garment design.However,there are few scientific investigations to explore this effect of muscle activation to evaluate the performance of sports compression garments during sport activity. In this paper, a systemic experimental protocol was presented to improve the quality of evaluation test under a standardized running test. Then muscle activation with and without wearing sport compression garments to highlight the changes caused by compression garment was investigated. The electromyography( EMG) signal was collected and processed by the proposed method to represent the muscle activation combined with gait analysis of running. As a result,the average muscle activation of gait cycle for the major muscles such as rectus femoris( RF) and gastrocnemius medialis( GM) revealed that they needed to exert more muscle force without wearing garment at certain periods for mid-stand and pre-swing phase within gait cycle. These lower muscle activation levels prolonged activity duration,reduced fatigue,and presented low risk for sport injury.Such an evaluation study therefore would scientifically prove the effect of compression garment and provide information on muscle activation and the ergonomic efficacy of gradient compression garment design. 相似文献
303.
根据青少年篮球运动员的生理特点,结合爆发力的训练机制,运用文献资料法,提出在适宜的年龄内最有效地发展青少年男子篮球运动员下肢力量相关的训练方法,旨在提高青少年篮球运动水平. 相似文献
304.
探讨肌醇磷脂代谢及其降解产物在大鼠输精管平滑肌收缩中的作用.用32P对输精管平滑肌进行标记,用薄层层析进行脂类分类,用放射自显影方法对磷脂进行定量研究,结果表明去甲肾上腺素能促进大鼠输精管平滑肌PI、PC、PA的代谢,PKC的大分子抑制剂和氯丙嗪不完全地抑制其代谢,Ca2+对上述反应有加速作用.本文提示去甲肾上腺素通过促进PI的代谢激活PKC,进而引起平滑肌的收缩,存在于输精管平滑肌中的PKC大分子蛋白抑制剂起着重要的调节作用. 相似文献
305.
观察了、猪、牛的发育生长过程,研究在发育生长过程中不同组织发育生长速度不同的现象,并首次对其分形表征的外显特性进行了讨论。 相似文献
306.
快速力量训练及减训对大鼠骨骼肌微细结构的影响 总被引:2,自引:0,他引:2
金雯 《苏州大学学报(医学版)》2006,22(3):86-89
研究了快速力量训练及减量训练对大鼠骨骼肌微细结构的影响.结论:减量训练会导致骨骼肌内糖原的减少和线粒体的增多,而且强度减得越多,这种变化越明显. 相似文献
307.
308.
To study the regulation of angiotensin Ⅱ(Ang Ⅱ) on Gαq/11 protein of vascular smooth muscle cell (VSMC) and its underlying mechanism, the protein synthesis was detected by [3H]-leucine incorporation. G?q/11 expression was measured by Western blot in cultured VSMC of rat aorta. The results showed that the level of G?q/11 was downregulated after stimulated by AngⅡ for 1-6 h, while it was upregulated significantly by 12-24 h stimulation (P < 0.01) in VSMC. The [3H]-leucine incorporation of VSMC was increased after 24 h Ang Ⅱ stimulation. The biphase regulation of Ang Ⅱ on G?q/11 protein was blocked by the Ang Ⅱ type Ⅰ receptor (AT1) specific antagnist losartan or PLC inhibitor U73122, while PD98059 did not have this effect. These data indicated that Ang Ⅱ contributed to VSMC hypertrophy by regulating the level of G?q/11, and this effect was mediated mainly through AT1 receptor-PLC signal transduction pathway. 相似文献
309.
J. L. Gainer M. G. Briscoe B. R. Holloway 《Cellular and molecular life sciences : CMLS》1993,49(1):68-72
The thermogenic action of beta-adrenoceptor agonists may be due, in part, to increased metabolism in skeletal muscle. Previous results suggest that vasoconstriction is also necessary, and that the effect can be blocked by vasodilators. Both noradrenaline and the beta-3 agonist, ICI D7114, were studied using two dog hindlimb protocols. During constant perfusion conditions, ICI D7114 caused a significant increase in hindlimb oxygen consumption although it is a vasodilator. Noradrenaline resulted in a smaller rise in oxygen consumption, and produced a marked vasoconstriction. Both noradrenaline and ICI D7114 resulted in decreased oxygen consumption when the blood flow was allowed to vary in response to the drug treatment. The results suggest that changes in tissue oxygen consumption caused by beta-agonists are not related to vasomotion. 相似文献
310.
呋喃西林和呋喃唑酮代谢物在大菱鲆组织中的消除规律 总被引:3,自引:0,他引:3
分别采用呋喃西林或呋喃唑酮单药给药及两种药物共同给药的方式,研究了其代谢物氨基脲(Semicarbazide, SEM)和3-氨基-2-噁唑烷基酮(3-amino-2-oxazolidinone,AOZ)在大菱鲆肌肉、肝脏和血液中的消除规律。结果表明,无论采用何种给药方式,呋喃西林和呋喃唑酮均能在大菱鲆组织中富集,并迅速代谢成SEM和AOZ。不同组织中,肝脏中SEM和AOZ的质量分数最高,其次为肌肉和血液;而同种组织则AOZ的质量分数远高于SEM,前者约为后者的10~30倍。而且两种给药方式下,SEM和AOZ在3种组织中都具有相似的消除规律:初始阶段均具有较高的消除速率,随后消除趋势趋于平缓,并在较长时间内维持一定质量分数,至实验结束时,3种组织中的SEM和AOZ质量分数都仍高于检出限。然而给药方式能够影响SEM和AOZ的富集质量分数及消除速率,如单药给药时SEM和AOZ在大菱鲆组织中的质量分数远高于共同给药下的质量分数,但消除半衰期(t_(1/2))却低于共同给药方式。结果表明硝基呋喃类药物的代谢物在大菱鲆组织中较难消除,具有较长的消除半衰期,应慎重将这类药物应用于大菱鲆疾病的治疗。 相似文献