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81.
基于带内自回传小基站系统,提出一种以用户为中心动态成簇的部分协作干扰抑制方案。根据带内自回传小基站复用接入与回传无线资源的特点,形成以最大化系统下行接入链路吞吐量为目标,联合回传链路资源分配与接入链路预编码设计的优化问题。由于所提问题难以获得最优解,基于凸松弛和分块坐标下降方法,提出一种次优的迭代求解算法。仿真结果表明所提算法能根据回传速率调整协作簇的大小,均衡小基站回传负载,提升系统接入链路的吞吐量。  相似文献   
82.
运动对GLUT4影响的研究进展   总被引:1,自引:0,他引:1  
葡萄糖跨膜转运是机体利用葡萄糖的首要步骤。葡萄糖载体(GLUT)是细胞膜上介导葡萄糖跨膜转运的蛋白质,它们对机体的葡萄糖利用有重要意义。运动可有效增加外周组织(主要为骨骼肌和脂肪组织)细胞膜葡萄糖载体4(GLUT4)的数量,使细胞内GLUT4的囊泡数量增多,GLUT4mRNA的表达增强,有效地加快血糖的转移、吸收和利用,解除外周组织胰岛素抵抗,调节血糖平衡,对糖尿病人的治疗有积极的作用和意义。  相似文献   
83.
我国体育产业发展的双重阻力   总被引:17,自引:0,他引:17  
我国GDP水平偏低,导致大众体育消费的有效消费不足;体育产业基础薄弱,体育产业结构不合理;体育人口众多与设施场地总量不足的矛盾:是我国体育产业发展的客观阻力。政府在体育产业中的职能定位存在偏差,职能转变缓慢,体育消费市场的实物消费远远大于体育劳务消费,则是我国体育产业发展的主观阻力。提出了在双重阻力作用下我国体育产业发展的思路。  相似文献   
84.
Physical inactivity (and unhealthy nutrition) has distorted body composition and, in turn, reordered the proportions of myocyte and adipocyte insulin receptors. Insulin acting on adipocyte receptors produces less glucose uptake than does comparable interaction with myocyte receptors. Accordingly, in individuals with disproportionate muscle/fat composition, any given glucose load requires greater-than-normal pancreatic insulin secretion for adequate disposal. This hyperinsulinemia then becomes the leading cause of type 2 diabetes (T2DM) as insulin-sensitive tissues become desensitized. Because T2DM is rooted in potentially reversible lifestyle factors, rather than focusing on the intricacies of glucoregulation at the molecular level and on testing new drugs to control blood sugar, this article calls for a new prevention and treatment paradigm, in which exercise and weight control are essential and for which an inexpensive and acceptably accurate measure of body muscle and fat proportions is needed.  相似文献   
85.
摘要:目的:探讨补充亮氨酸对无训练史被试进行抗阻运动所致骨骼肌损伤的影响。方法:16名青年男性大学生据体重随机分为补充亮氨酸组与安慰剂对照组,亮氨酸和安慰剂组被试从测试日深蹲抗阻运动前3周直至运动后4 d分别以每千克体重150 mg剂量摄入150 mL亮氨酸或糊精溶液。测试日各组被试以50% 1RM负荷完成5组深蹲运动,每组20次,组间间歇2 min。深蹲运动前于肘正中静脉采集血样,测量大腿围、纵跳高度、膝关节活动幅度与肌肉酸痛程度,并于运动后即刻、24 h、48 h、72 h和96 h重复测试。ELISA法检测血清CK-MM、Mb与血浆IL-6,胶乳增强免疫比浊法检测血清CRP。结果:与安慰剂组被试相比,补充亮氨酸显著降低了亮氨酸组被试运动后延迟性肌肉酸痛水平、大腿中段周长及血清CK-MM、Mb、CRP与血浆IL-6含量,而深蹲1-RM值、纵跳高度及膝关节ROM组间差异则并无统计学意义。结论:1)每千克体重150 mg剂量亮氨酸能够削弱抗阻运动所导致的骨骼肌损伤与疼痛,该效应可能与对炎症反应的抑制有关,且推测亮氨酸对骨骼肌蛋白质代谢平衡的调节作用在其中亦有贡献;2)该剂量亮氨酸不能明显促进工作肌机能恢复。  相似文献   
86.
探讨全身性振动介入抗阻力训练对能量消耗的影响,为体重控制及健身减肥者制定有效的运动处方提供依据。方法:以我院体育教育专业健康男性为对象,利用气体代谢分析仪及心率表对"振动介入+抗阻力训练"(实验组,Resistance exercise+Vibration,REV)及单纯"抗阻力训练"(对照组,Resistance exercise, RE)模式下的摄氧及能量消耗等指标进行监测,并运用SPSS17.0对相关指标进行统计分析。结果:1)REV组在训练中及训练后0-25分、25-50分的总每分钟能量消耗及每分钟最大摄氧显著高于RE组;2)抗阻力训练结束后相当长的时间内以脂肪消耗供能为主,表现为REV组脂肪供能比例明显高于RE组;3)抗阻力训练能显著提升训练中呼吸交换率及换气量,表现为REV组提升率高于RE组。结论:全身性振动介入抗阻力训练可比单纯抗阻力增加更多能量消耗,且在训练后恢复期能提升脂肪供能比例,故控体重运动员及健身减肥者将振动作为辅助训练手段是非常有效的。  相似文献   
87.
Purpose: There is a paucity of research investigating the expression of mitogen-activated protein kinases (MAPK) in chronically trained (CT) athletes. Thus, it is unclear how MAPK may contribute to performance and muscle adaptation in CT subjects. The purpose of this study was to determine MAPK total protein, and phosphorylated expression of extracellular signal-regulated kinases 1 and 2 (ERK1/2), c-Jun N-terminal kinase (JNK), and p38-MAPK (p38) between untrained, and chronically trained runners. Methods: Tissue samples were analysed from sedentary (SED; n?=?5) controls and chronically trained runners (CT; n?=?5). Resting muscle biopsy samples were analysed for total-MAPK – and ratio of phosphorylated/total (p-MAPK) – ERK1/2, JNK, and p38-MAPK via western blotting. Mann–Whitney U tests and effect sizes were utilized to determine differences in total MAPK protein content and phosphorylation status between SED and CT subjects. Results: There was no difference in total-MAPK expression between SED and CT (p?>?.05). p-p38-MAPK tended to be greater for CT compared to SED (p?=?.07). There were moderate effect sizes of decreased pERK/total-ERK (d?=??0.69) and increased pJNK/total-JNK (d?=?0.54) in CT compared to SED. There was a positive correlation between p-p38-MAPK/total-MAPK and the percentage of type I fibres (r?=?0.73, p?=?.016). Conclusion: Contrary to previous studies, chronic endurance training does not greatly influence total MAPK protein expression in chronically trained runners. However, resting phosphorylation of p38-MAPK may contribute to enhanced oxidative metabolism at chronically trained levels. These alterations are likely involved in the different physiological adaptations that occur following long-term training or at highly competitive levels.  相似文献   
88.
Focusing on the online Chinese fans of Japanese TV drama, this paper explores the way in which the fan subculture, in connection with digital technologies, has carved out alternative practices in the circulation, production and consumption of Japanese TV drama. As ‘minority audiences’ who are not targeted as the objects of capitalist interests, online Chinese fans invent spaces for Chinese transnational networking with self‐help and sharing, as a way of resisting the aloofness from marketing strategies of Japanese TV distributors in Asia. This case study reveals that the online Chinese fan clubs, the websites for downloads, pirated VCD markets, digital file conversion, and private VCD burning – all of these have linked endless networks for the digitalized circulation and consumption of Japanese TV drama. The online Chinese fans are guerrilla fighters in the politics of autonomy, network and low‐cost digital technology; they are attempting to break down time–space constraints and the official distribution hierarchy. Such fan practices shed light on the new trends of audio‐visual consumption via digitalization.  相似文献   
89.
Abstract

This essay recognizes that representations of the ‘Muslim woman’ as the Othered ‘object’ of the ‘Western’ gaze and the domesticated ‘object’ which the Islamic apologists strive hard to defend, are both constructions and false antitheses of each other. It seeks not the ‘truth’ regarding the Muslim women in the world of social reality but to examine how various representations of the women are constructed and to what effects and consequences these representations are mobilized. The essay proceeds in three stages. The first stage shows how the patriarchy mobilizes the Qur’an and the Hadith in order to construct the woman as the negative, the inessential and the abnormal of the man so as to exert complete subordination over her. However, the very act of attempting to mute the woman in Islam is the most strident proof that she is engaged in resistance against patriarchal control and the degree of resistance must be judged by the degree of patriarchal control. The second stage demonstrates how patriarchy operates in colonial and neo‐imperial landscape: it legitimizes the appropriation of Muslim woman ‘possessed’ by the Other (as exemplified by the orientalist seduction fantasy in William Dalrymple’s The White Mughals), but, haunted by the fear of rape and anxieties regarding the sexuality of the White woman possessed by the Self, it attempts to maintain strict control over her (as in the cases of Miss Wheeler in the ‘Mutiny’ of 1857 and Private Jessica Lynch in the Iraq War). This struggle over the feminine body is perfectly in line with Islam’s hyper‐anxiousness to hide the female body and rigorously ensure monopolic possession over her. The third stage shows how Taslima Nasreen, a late‐20th century feminist from Bangladesh, speaks the unspoken and thereby attempts to subvert the normative representation of the muted women in her autobiographical novella, entitled āmār Meyebelā. In thus examining the representations of the Muslim women, this essay seeks an alternative ‘third space of enunciation’ and takes a distinct political stand located outside of the axis of the dichotomy of the ‘Western’ gaze and the construction of the Islamic theologians.  相似文献   
90.
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