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   42737篇
  免费   670篇
  国内免费   28篇
教育   30487篇
科学研究   3677篇
各国文化   458篇
体育   3689篇
综合类   19篇
文化理论   363篇
信息传播   4742篇
  2021年   443篇
  2020年   680篇
  2019年   1047篇
  2018年   1411篇
  2017年   1371篇
  2016年   1235篇
  2015年   752篇
  2014年   1096篇
  2013年   8156篇
  2012年   1012篇
  2011年   1084篇
  2010年   810篇
  2009年   858篇
  2008年   939篇
  2007年   862篇
  2006年   778篇
  2005年   704篇
  2004年   705篇
  2003年   607篇
  2002年   623篇
  2001年   812篇
  2000年   807篇
  1999年   700篇
  1998年   435篇
  1997年   429篇
  1996年   503篇
  1995年   451篇
  1994年   404篇
  1993年   395篇
  1992年   584篇
  1991年   596篇
  1990年   578篇
  1989年   604篇
  1988年   540篇
  1987年   562篇
  1986年   536篇
  1985年   611篇
  1984年   493篇
  1983年   475篇
  1982年   402篇
  1981年   378篇
  1980年   389篇
  1979年   557篇
  1978年   408篇
  1977年   373篇
  1976年   329篇
  1975年   293篇
  1974年   306篇
  1973年   283篇
  1971年   294篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
There is limited information on the anthropometry, strength, endurance and flexibility of female rock climbers. The aim of this study was to compare these characteristics in three groups of females: Group 1 comprised 10 elite climbers aged 31.3 +/- 5.0 years (mean +/- s) who had led to a standard of 'hard very severe'; Group 2 consisted of 10 recreational climbers aged 24.1 +/- 4.0 years who had led to a standard of 'severe'; and Group 3 comprised 10 physically active individuals aged 28.5 +/- 5.0 years who had not previously rock-climbed. The tests included finger strength (grip strength, finger strength measured on climbing-specific apparatus), flexibility, bent arm hang and pull-ups. Regression procedures (analysis of covariance) were used to examine the influence of body mass, leg length, height and age. For finger strength, the elite climbers recorded significantly higher values (P < 0.05) than the recreational climbers and non-climbers (four fingers, right hand: elite 321 +/- 18 N, recreational 251 +/- 14 N, non-climbers 256 +/- 15 N; four fingers, left hand: elite 307 +/- 14 N, recreational 248 +/- 12 N, non-climbers 243 +/- 11 N). For grip strength of the right hand, the elite climbers recorded significantly higher values than the recreational climbers only (elite 338 +/- 12 N, recreational 289 +/- 10 N, non-climbers 307 +/- 11 N). The results suggest that elite climbers have greater finger strength than recreational climbers and non-climbers.  相似文献   
62.
63.
64.
This article discusses the changing relationships of authors and publishers, the current trends and challenges they face, and the direction of these relationships in the future. As the STM publishing industry finds itself in the midst of significant technological and economic changes, this article provides background to these changes and looks at the key elements, including open access business development, institutional repository trends, and emerging public financing policies in the future.  相似文献   
65.
66.
ABSTRACT It is argued that sport, like science or medicine, is a valued human practice and is characterised as much by the moral manner in which its participants conduct themselves as by the pursuit of its own skills, standards and excellences. Virtues, such as justice, honesty and courage, are not only necessary to pursue its goals but to protect it from being corrupted by external interests. After explicating the practice view of sport in contrast to the sociological view, the nature of competition in sport is discussed before examining two related issues: winning at all costs and the taking of performance-enhancing drugs. The importance of practices to education and the good life is also outlined.  相似文献   
67.
Medicine has made increasing use of meta-analysis, largely as a quantitative procedure for combining results of clinical trials. Meta-analysis begins with a comprehensive review of the literature. The next step is a systematic analysis of the quality and content of each study. Finally, results are combined statistically and conclusions are drawn from this new overview of the data. This paper presents a brief historical perspective on the use of meta-analysis in medicine with emphasis on the medical library. The authors conclude that in the future, medical librarians will play a significant role in the application of this useful technique.  相似文献   
68.
This investigation was undertaken in an effort to establish physiological characteristics of soccer players and to relate them to positional roles. A total of 135 footballers (age 24.4 +/- 4.6 years) were assessed for body mass, % body fat, haemoglobin, maximal oxygen uptake (VO2 max), leg power, anaerobic capacity and speed prior to an English league season. The sample included 13 goalkeepers, 22 full-backs, 24 centre-backs, 35 midfield players and 41 forwards. The goalkeepers were significantly heavier (86.1 +/- 5.5 kg; P < 0.01) than all groups except the centre-backs, had significantly higher estimated body fat percentages than centre-backs, forwards, midfield players (P < 0.01) or full-backs (P < 0.05), significantly lower estimated VO2 max values (56.4 +/- 3.9 ml kg-1 min-1; P < 0.01) and were slowest over 60 m (12.71 +/- 0.42 s). The midfield players had the highest predicted VO2 max values (61.4 +/- 3.4 ml kg-1 min-1), this being significantly greater (P < 0.05) than for the centre-backs. The forwards were the fastest group over 60 m (12.19 +/- 0.30 s), being significantly quicker than goalkeepers or centre-backs (P < 0.01) and full-backs (P < 0.05). Anaerobic power, as well as knee extensor torques (corrected for body mass) and extensor-flexor ratios, were similar between groups. No difference in estimated body fat percentage was observed between any of the outfield players, and haemoglobin concentrations were similar among players of all positions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
69.
初论举重运动员的重量感   总被引:2,自引:0,他引:2  
重量感是举重运动员在运动过程中的 1种专门化的运动知觉。从训练和比赛实践中积累的大量资料中列举部分实例来说明重量感在训练和比赛中的典型表现形式 ,着重讨论了重量感的定义、形成过程及主要特征。由于目前举重界对重量感形成的机制、原理尚不清楚 ,在一定程度上影响了选材和训练过程 ,对此问题进行深入的研究和开发十分必要  相似文献   
70.
Buxton  William J. 《Minerva》2003,41(2):133-153
John Marshall is best remembered asthe first resident director of the RockefellerFoundation's Study and Conference Center atBellagio. Yet, his influence on knowledge,thought, and practice rivalled that of any ofhis contemporaries at the Rockefeller. Thispaper describes how he `went about hisbusiness' as a Foundation officer, and examineshis contribution to the creation of atransatlantic community of like-mindedtheorists and practitioners of communications.  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