首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   240篇
  免费   2篇
教育   178篇
科学研究   14篇
各国文化   5篇
体育   9篇
综合类   5篇
文化理论   2篇
信息传播   29篇
  2023年   1篇
  2022年   3篇
  2021年   3篇
  2020年   3篇
  2019年   5篇
  2018年   7篇
  2017年   8篇
  2016年   7篇
  2015年   8篇
  2014年   8篇
  2013年   42篇
  2012年   42篇
  2011年   30篇
  2010年   12篇
  2009年   8篇
  2008年   6篇
  2007年   2篇
  2006年   8篇
  2005年   7篇
  2004年   10篇
  2003年   2篇
  2002年   3篇
  2001年   1篇
  2000年   1篇
  1999年   1篇
  1997年   1篇
  1996年   1篇
  1995年   1篇
  1993年   1篇
  1988年   1篇
  1982年   1篇
  1980年   4篇
  1979年   1篇
  1978年   2篇
  1975年   1篇
排序方式: 共有242条查询结果,搜索用时 15 毫秒
11.
The behavioural modifications that accompany Ramadan intermittent fasting (RIF) are usually associated with some alterations in the metabolic, physiological, and psychological responses of athletes that may affect sport performance. Muslim athletes who are required to train and/or compete during the month-long, diurnal fast must adopt coping strategies that allow them to maintain physical fitness and motivation if they are to perform at the highest level. This updated review aims to present the current state of knowledge of the effects of RIF on training and performance, focusing on key-factors that contribute to the effects of Ramadan on exercise performance: energy restriction, sleep deprivation, circadian rhythm perturbation, dehydration, and alterations in the training load. The available literature contain few studies that have examined the effects of RIF on physical performance in athletes and, to date, the results are inconclusive, so the effects of RIF on competition outcomes are not at present wholly understood. The diverse findings probably indicate individual differences in the adaptability and self-generated coping strategies of athletes during fasting and training. However, the results of the small number of well-controlled studies that have examined the effects of Ramadan on athletic performance suggest that few aspects of physical fitness are negatively affected, and where decrements are observed these are usually modest. Subjective feelings of fatigue and other mood indicators are often cited as implying additional stress on the athlete throughout Ramadan, but most studies show that these factors may not result in decreases in performance and that perceived exercise intensity is unlikely to increase to any significant degree. Current evidence from good, well-controlled research supports the conclusion that athletes who maintain their total energy and macronutrient intake, training load, body composition, and sleep length and quality are unlikely to suffer any substantial decrements in performance during Ramadan. Further research is required to determine the effect of RIF on the most challenging events or exercise protocols and on elite athletes competing in extreme environments.  相似文献   
12.
The Muslim athlete, whether living in a Muslim majority country or in a non-Muslim country, face unique challenges to faithfully follow one of the pillars of their faith - Ramadan - while attempting to maintain their participation in sports training and competition. There are conflicting reports on the effects of Ramadan on fitness and physical performance in general and in football in particular. In general, the impact of a brief daytime fast has minor effects on health or factors of physical fitness. Add physical training and now a new set of barriers to both performance and the observance of Ramadan begin to interact. Practising athletes have worked out strategies to cope with the rigors of Ramadan; strategies that have both physical (training modifications, dietary habits, rest and recovery) and emotional (patience, emotional preparations) domains. Carefully blending strategies like these can help the football player be true to their faith and follow the tenants of Ramadan hopefully, with a minimum of impact on their physical performance. In this context, science can help coaches improve their training plans and educate players with respect to the challenges presented by Ramadan to all levels of sports participation.  相似文献   
13.
目的观察火针治疗前后大鼠跟腱末端区细胞凋亡情况的变化,探讨火针治疗末端病的作用机理,为末端病的火针治疗提供理论依据。方法采用"电击跳跃法"建立大鼠跟腱末端病模型,施以火针治疗,采用TUNEL法检测细胞凋亡指数(AI)。结果(1)1次火针治疗后,治疗组大鼠末端区主要在跟腱、纤维软骨区、腱围这三个部位的AI比对照组有不同程度降低;(2)经4次火针治疗后,跟腱、纤维软骨区、腱骨关节面软骨、腱围的AI明显低于对照组;(3)4次火针治疗后在跟腱、纤维软骨区、腱骨关节面软骨、腱围的AI明显低于1次火针治疗组。结论(1)8周的"电击跳跃法"成功建立了大鼠跟腱末端病模型。(2)1次火针治疗可以减少末端区的细胞凋亡和修复已凋亡的细胞。(3)4次火针治疗不仅使末端区的凋亡细胞得到修复,而且加速了整个末端区组织和结构的恢复。  相似文献   
14.
对云南省高校开设少数民族传统体育项目公选课的意义、可行性及实施建议进行了阐述,以期促进少数民族传统体育项目得到更好的保护和推广,同时为高校体育教学改革提供一些参考.  相似文献   
15.
在介绍虚拟展示模式的基础上,以开发虚拟展馆漫游系统为例,以3DS MAX和Cult 3D为工具,讨论了开发虚拟展馆漫游系统的基本原理、步骤以及控制过程,最终在网页上建立互动产品模型。并讨论了虚拟展示技术的发展前景,认为在多媒体演示交互中具有广阔的应用前景。  相似文献   
16.
Mycorrhizoremediation an enhanced form of phytoremediation   总被引:2,自引:0,他引:2  
Study of plant roots and the diversity of soil micro biota, such as bacteria, fungi and microfauna associated with them, is important for understanding the ecological complexities between diverse plants, microbes, soil and climates and their role in phytoremediation of contaminated soils. The arbuscular mycorrhizal fungi (AMF) are universal and ubiquitous rhizosphere mi- croflora forming symbiosis with plant roots and acting as biofertilizers, bioprotactants, and biodegraders. In addition to AMF, soils also contain various antagonistic and beneficial bacteria such as root pathogens, plant growth promoting rhizobacteria including free-living and symbiotic N-fixers, and mycorrhiza helping bacteria. Their potential role in phytoremediation of heavy metal (HM) contaminated soils and water is becoming evident although there is need to completely understand the ecological complexities of the plant-microbe-soil interactions and their better exploitation as consortia in remediation strategies employed for contaminated soils. These multitrophic root microbial associations deserve multi-disciplinary investigations using molecular, biochemical, and physiological techniques. Ecosystem restoration of heavy metal contaminated soils practices need to incorporate microbial biotechnology research and development. This review highlights the ecological complexity and diversity of plant-microbe-soil combinations, particularly AM and provides an overview on the recent developments in this area. It also discusses the role AMF play in phytorestoration of HM contaminated soils, i.e. mycorrhizoremediation.  相似文献   
17.
18.
利用高温固相反应法制备了新型锂离子电池正极材料Li2Ru0.5Co0.5O3.通过X射线衍射技术和电化学性能测试对Li_2Ru_(0.5)Co_(0.5)O_3的微观结构及其电化学性能进行了表征.研究结果表明,该新材料为六方层状结构,空间群为R-3M;电化学性能测试表明,该材料具有良好的比容量和循环性能,在电压范围2.5V~4.8V内,以16mA/g的电流密度,其初始充电比容量达240mAh/g,初始放电比容量为175mAh/g,40次循环后容量保持率为78%.  相似文献   
19.
Searching for relevant material that satisfies the information need of a user, within a large document collection is a critical activity for web search engines. Query Expansion techniques are widely used by search engines for the disambiguation of user’s information need and for improving the information retrieval (IR) performance. Knowledge-based, corpus-based and relevance feedback, are the main QE techniques, that employ different approaches for expanding the user query with synonyms of the search terms (word synonymy) in order to bring more relevant documents and for filtering documents that contain search terms but with a different meaning (also known as word polysemy problem) than the user intended. This work, surveys existing query expansion techniques, highlights their strengths and limitations and introduces a new method that combines the power of knowledge-based or corpus-based techniques with that of relevance feedback. Experimental evaluation on three information retrieval benchmark datasets shows that the application of knowledge or corpus-based query expansion techniques on the results of the relevance feedback step improves the information retrieval performance, with knowledge-based techniques providing significantly better results than their simple relevance feedback alternatives in all sets.  相似文献   
20.
Tertiary Education and Management - Evaluation of research performance has significantly increased in importance, particularly in many emerging higher education systems. In Malaysia, the Malaysian...  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号