全文获取类型
收费全文 | 13877篇 |
免费 | 210篇 |
国内免费 | 23篇 |
专业分类
教育 | 9637篇 |
科学研究 | 1581篇 |
各国文化 | 130篇 |
体育 | 1225篇 |
综合类 | 6篇 |
文化理论 | 105篇 |
信息传播 | 1426篇 |
出版年
2021年 | 151篇 |
2020年 | 203篇 |
2019年 | 293篇 |
2018年 | 390篇 |
2017年 | 369篇 |
2016年 | 380篇 |
2015年 | 251篇 |
2014年 | 333篇 |
2013年 | 2394篇 |
2012年 | 315篇 |
2011年 | 333篇 |
2010年 | 292篇 |
2009年 | 236篇 |
2008年 | 287篇 |
2007年 | 251篇 |
2006年 | 239篇 |
2005年 | 215篇 |
2004年 | 231篇 |
2003年 | 213篇 |
2002年 | 180篇 |
2001年 | 451篇 |
2000年 | 296篇 |
1999年 | 256篇 |
1998年 | 123篇 |
1997年 | 162篇 |
1996年 | 135篇 |
1995年 | 126篇 |
1994年 | 154篇 |
1993年 | 118篇 |
1992年 | 185篇 |
1991年 | 196篇 |
1990年 | 198篇 |
1989年 | 200篇 |
1988年 | 170篇 |
1987年 | 160篇 |
1986年 | 170篇 |
1985年 | 211篇 |
1984年 | 162篇 |
1983年 | 150篇 |
1982年 | 130篇 |
1981年 | 126篇 |
1980年 | 115篇 |
1979年 | 165篇 |
1978年 | 131篇 |
1977年 | 117篇 |
1976年 | 92篇 |
1975年 | 114篇 |
1974年 | 101篇 |
1973年 | 111篇 |
1971年 | 98篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
PAMELA C. STEWART 《Health information and libraries journal》1986,3(3):153-159
相似文献
53.
54.
55.
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
56.
C A Perry 《Bulletin of the Medical Library Association》1990,78(3):271-282
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
57.
Tseng SC Arcand JL Brugger JM Finn M Olson AJ Somers S 《Library resources & technical services》1990,34(2):139-157
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
58.
59.
60.
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