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   15131篇
  免费   225篇
  国内免费   21篇
教育   10665篇
科学研究   1638篇
各国文化   142篇
体育   1223篇
综合类   8篇
文化理论   124篇
信息传播   1577篇
  2021年   165篇
  2020年   231篇
  2019年   318篇
  2018年   426篇
  2017年   427篇
  2016年   418篇
  2015年   277篇
  2014年   376篇
  2013年   2770篇
  2012年   340篇
  2011年   369篇
  2010年   324篇
  2009年   258篇
  2008年   306篇
  2007年   273篇
  2006年   261篇
  2005年   244篇
  2004年   256篇
  2003年   234篇
  2002年   200篇
  2001年   462篇
  2000年   315篇
  1999年   274篇
  1998年   134篇
  1997年   165篇
  1996年   154篇
  1995年   135篇
  1994年   161篇
  1993年   126篇
  1992年   198篇
  1991年   206篇
  1990年   208篇
  1989年   209篇
  1988年   176篇
  1987年   167篇
  1986年   177篇
  1985年   220篇
  1984年   169篇
  1983年   162篇
  1982年   144篇
  1981年   130篇
  1980年   126篇
  1979年   179篇
  1978年   143篇
  1977年   123篇
  1976年   98篇
  1975年   116篇
  1974年   103篇
  1973年   114篇
  1971年   103篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
The American Hospital Association (AHA) Resource Center indexes journals for the Health Planning and Administration (HEALTH) database and Hospital Literature Index (HLI). These journals, designated special list health journals, are selected to provide access to a wide and balanced coverage of hospital and health care administration and health policy literature. This article provides background information on HEALTH and HLI and describes special list health journals in detail (including historical information, information sources, and broad subject divisions). It also discusses AHA policies relating to journal and article selection and current subject distribution of special list health journals.  相似文献   
63.
Efforts to represent knowledge effectively have been central to progress in various aspects of medical informatics. These efforts range from relatively simple "electronic textbooks" to fairly sophisticated knowledge-based systems, which function as well as, or even better than, human experts faced with similar problems. Knowledge bases have been developed in many fields, but the relatively limited domains and structured language of medicine, as well as the importance of information in the provision of good medical care, have made research in medical knowledge representation an area of intense activity. This paper reviews representative knowledge bases and knowledge-based systems in medicine: electronic textbooks such as PDQ and the Hepatitis Knowledge Base (HKB), rule-based systems such as MYCIN, causal models (e.g., CASNET), and hypothesis- or frame-based systems, exemplified by PIP and INTERNIST-1. The paper describes the relationships among divergent approaches and provides a sense of current and future trends. It examines problems in knowledge-based systems, particularly in knowledge representation and acquisition, and the responses to these challenges. The latter include the use of domain-independent software shells for constructing knowledge bases, the adaptation and use of previously existing knowledge bases, and multiple uses of the same knowledge base for different purposes.  相似文献   
64.
Serials, one of the more complicated areas of library technical endeavors, has lacked the benefit of standards for a long time. Even now, with standards beginning to be available, the majority of institutions are not working within standard serials formats. A survey to determine the use of serials standards in libraries was conducted in 1988 by the American Library Association, Resources and Technical Services Division, Serials Section, Committee to Study Serials Standards. In the spring of 1988 a survey was sent to a group encompassing the Association of Research Libraries members, CONSER participants, United States Newspaper Program participants, Microform Project libraries, and some vendors and librarians who attended the Committee meetings on a regular basis. The survey questionnaire assessed the current level of serials standards awareness of librarians and vendors. Topics included the type of serials systems used, standards relevant to serials control and union listing and whether or not they are implemented, types and levels of training staff received in the application of standards, benefits of the standards, and areas where standards are most needed.  相似文献   
65.
66.
67.
We theorize about the strategic alignment of computing with organizational mission, using the Commonwealth of Pennsylvania's efforts to pursue digital government initiatives as evidence. To do this we draw on a decade (1995–2004) of changes in Pennsylvania to characterize how a state government shifts from an organizational to an enterprise perspective regarding computing. We document and analyze the strategic and operational aspects of a series of information and communications technology (ICT) planning efforts to highlight the nature and roles of strategic alignment used to achieve this transition. Findings from this analysis mark the importance of combining several approaches to strategic planning regarding the adoption and application of ICT.  相似文献   
68.
69.
This study explores faculty deposits in institutional repositories (IR) within selected disciplines and identifies the diverse navigational paths to IR sites from library Web site homepages. The statistical relationship between the development of an IR and the presence of a Web site dedicated to the reform of traditional scholarly communication is also explored. The implications for the development of institutional repositories are highlighted.  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