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   38007篇
  免费   524篇
  国内免费   25篇
教育   26819篇
科学研究   3885篇
各国文化   363篇
体育   3084篇
综合类   30篇
文化理论   429篇
信息传播   3946篇
  2021年   353篇
  2020年   538篇
  2019年   777篇
  2018年   1137篇
  2017年   1130篇
  2016年   1165篇
  2015年   733篇
  2014年   897篇
  2013年   6342篇
  2012年   907篇
  2011年   957篇
  2010年   744篇
  2009年   698篇
  2008年   796篇
  2007年   749篇
  2006年   707篇
  2005年   1183篇
  2004年   1088篇
  2003年   800篇
  2002年   676篇
  2001年   778篇
  2000年   795篇
  1999年   658篇
  1998年   391篇
  1997年   421篇
  1996年   468篇
  1995年   360篇
  1994年   376篇
  1993年   324篇
  1992年   512篇
  1991年   530篇
  1990年   523篇
  1989年   533篇
  1988年   482篇
  1987年   481篇
  1986年   463篇
  1985年   540篇
  1984年   420篇
  1983年   422篇
  1982年   349篇
  1981年   339篇
  1980年   357篇
  1979年   492篇
  1978年   368篇
  1977年   339篇
  1976年   285篇
  1975年   260篇
  1974年   268篇
  1973年   253篇
  1971年   250篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
81.
82.
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   
83.
84.
The roles of academic health sciences librarians are continually evolving as librarians initiate new programs and services in response to developments in computer technology and user demands. However, statistics currently collected by libraries do not accurately reflect or measure these new roles. It is essential for librarians to document, measure, and evaluate these new activities to continue to meet the needs of users and to ensure the viability of their professional role. To determine what new measures should be compiled, the authors examined current statistics, user demands, professional literature, and current activities of librarians as reported in abstracts of poster sessions at Medical Library Association annual meetings. Three new categories of services to be measured are proposed. The first, consultation, groups activities such as quality filtering and individual point-of-need instruction. The second, outreach, includes activities such as working as liaisons, participating in grand rounds or morning report, and providing continuing education. The third area, Web authoring, encompasses activities such as designing Web pages, creating online tutorials, and developing new products. Adding these three measures to those already being collected will provide a more accurate and complete depiction of the services offered by academic health sciences librarians.  相似文献   
85.
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   
86.
87.
The many challenges faced by health sciences libraries of all types and sizes often require innovative solutions. When an innovative solution involves calculated risk taking, the approach is called intrapreneurial. At the University of Miami School of Medicine, an intrapreneurial approach solved the fiscal problems of the biomedical communications unit. The Louis Calder Memorial Library inherited these problems when the Department of the Library and Biomedical Communications was created in the early 1980s. In this paper, two intrapreneurial programs are described, and the benefit and suitability of this management style to information services are demonstrated.  相似文献   
88.
89.
A case presentation method of group supervision, as practiced at a community college, is described. Developmental principles underlying this approach are presented.  相似文献   
90.
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