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   31839篇
  免费   473篇
  国内免费   22篇
教育   22892篇
科学研究   2431篇
各国文化   415篇
体育   2920篇
综合类   10篇
文化理论   338篇
信息传播   3328篇
  2021年   311篇
  2020年   502篇
  2019年   759篇
  2018年   1016篇
  2017年   977篇
  2016年   955篇
  2015年   611篇
  2014年   769篇
  2013年   6092篇
  2012年   712篇
  2011年   750篇
  2010年   606篇
  2009年   596篇
  2008年   734篇
  2007年   640篇
  2006年   612篇
  2005年   541篇
  2004年   537篇
  2003年   489篇
  2002年   491篇
  2001年   590篇
  2000年   625篇
  1999年   545篇
  1998年   361篇
  1997年   356篇
  1996年   426篇
  1995年   377篇
  1994年   371篇
  1993年   320篇
  1992年   457篇
  1991年   473篇
  1990年   444篇
  1989年   455篇
  1988年   422篇
  1987年   390篇
  1986年   390篇
  1985年   442篇
  1984年   357篇
  1983年   382篇
  1982年   311篇
  1981年   321篇
  1980年   335篇
  1979年   417篇
  1978年   310篇
  1977年   286篇
  1976年   252篇
  1975年   226篇
  1974年   221篇
  1973年   208篇
  1971年   203篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
Co-production occurs when two or more institutions contribute funds and labour to the processes of making course components for distance teaching. The author summarises reasons for international co-production of multimedia distance-teaching courses and provides a checklist of questions that should be considered before entering upon such co-production.
The second half of the article consists of a composite case study based on the UK's Open University experience of international co-production. The paper ends with three questions: Is international co-production of this kind worth trying? Can the chances of success be made high enough by careful planning to justify risking capital in such ventures? Are other forms of collaboration more likely to be cost-effective?  相似文献   
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.
黄维  David 《文化交流》2006,(4):50-52
她是世界上惟一一位集奥赛、世界杯和世锦赛三项冠军于一身的棋手,也是继谢军、诸宸之后的第三位世界“棋后”,她的名字叫许昱华。  相似文献   
66.
67.
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   
68.
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   
69.
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   
70.
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