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   15464篇
  免费   186篇
  国内免费   11篇
教育   10583篇
科学研究   2014篇
各国文化   120篇
体育   1055篇
综合类   5篇
文化理论   102篇
信息传播   1782篇
  2021年   160篇
  2020年   210篇
  2019年   311篇
  2018年   475篇
  2017年   420篇
  2016年   406篇
  2015年   250篇
  2014年   389篇
  2013年   2676篇
  2012年   333篇
  2011年   364篇
  2010年   320篇
  2009年   288篇
  2008年   347篇
  2007年   288篇
  2006年   280篇
  2005年   250篇
  2004年   287篇
  2003年   207篇
  2002年   214篇
  2001年   308篇
  2000年   302篇
  1999年   275篇
  1998年   160篇
  1997年   192篇
  1996年   182篇
  1995年   133篇
  1994年   147篇
  1993年   149篇
  1992年   262篇
  1991年   230篇
  1990年   216篇
  1989年   231篇
  1988年   207篇
  1987年   194篇
  1986年   194篇
  1985年   203篇
  1984年   167篇
  1983年   184篇
  1982年   153篇
  1981年   144篇
  1980年   135篇
  1979年   196篇
  1978年   153篇
  1977年   146篇
  1976年   126篇
  1975年   102篇
  1974年   122篇
  1973年   115篇
  1972年   98篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.
33.
34.
35.
36.
Acquiring both published and unpublished documents produced in Africa is, generally, a difficult task due to the existing poor state of bibliographic control and the publishing industry. It is even more difficult to obtain unpublished documents in a specialized area of study such as demography--a diffuse area which cuts across several disciplines. This paper discusses the problems encountered on acquisition trips to some African countries to acquire unpublished population material. To help solve the problems, the Population Association of Africa must persuade its members to send copies of their publications to population libraries and documentation centers in their individual countries for dissemination to the other users in Africa. The various organizations and institutions in Africa engaged in the teaching and research of population studies should have an agreement to exchange copies of their theses. The Economic Commission for Africa (ECA) and the Organization of African Unity (OAU) should make representations to the various African member countries on the need to disseminate the results of vital censuses and surveys conducted. Finally, the Population Information Network for Africa (POPIN-AFRICA) with its coordinating unit at the population division of ECA should ensure that all the nodes of the network have the financial and other resources to be able to acquire the relevant documents needed for their operations.  相似文献   
37.
38.
Computers are integral to medical practice, education, and research. While medical students learn computer skills during their training, many practicing physicians do not have the same computer experience. To familiarize this group with the exciting developments in medical informatics, the Himmelfarb Health Sciences Library and Department of Computer Medicine at the George Washington University Medical Center organized a workshop "Introducing Your Office Computer!" for attending physicians. The workshop featured a short lecture/video presentation on computer applications in medicine followed by a "computer fair" of five computer applications. Eleven physicians attended the workshop. Feedback was very positive; many called later to request more detailed instructions on using the programs demonstrated. It was a valuable experience for the staff, and new bridges were built between departments and clients.  相似文献   
39.
The National Library of Medicine has had an enormous impact on health information services all over the world. Although NLM is primarily a national institution, it has become an important international resource by responding to requests from the international community. NLM has been influential in three major ways. First, NLM has provided a model for other national and regional health information services. Second, it has been a catalyst, in that MEDLARS and other services it provides formed the nucleus of many regional networks. NLM helped such networks get started by giving advice on how to set up services and build collections and by "training the trainers" on the MEDLARS system. Third, NLM has supported national and regional operations by providing the additional training and materials needed for day-to-day service.  相似文献   
40.
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