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   54161篇
  免费   2235篇
  国内免费   30篇
  56426篇
  2020年   667篇
  2019年   837篇
  2018年   1196篇
  2017年   1183篇
  2016年   1226篇
  2015年   832篇
  2014年   1005篇
  2013年   4765篇
  2012年   1790篇
  2011年   1942篇
  2010年   1117篇
  2009年   1159篇
  2008年   1727篇
  2007年   1704篇
  2006年   1492篇
  2005年   1345篇
  2004年   1317篇
  2003年   1182篇
  2002年   1227篇
  2001年   1769篇
  2000年   1662篇
  1999年   1282篇
  1998年   680篇
  1997年   579篇
  1996年   521篇
  1995年   525篇
  1994年   503篇
  1993年   522篇
  1992年   1014篇
  1991年   960篇
  1990年   946篇
  1989年   857篇
  1988年   817篇
  1987年   805篇
  1986年   812篇
  1985年   857篇
  1984年   671篇
  1983年   579篇
  1982年   477篇
  1979年   656篇
  1978年   487篇
  1976年   450篇
  1975年   591篇
  1974年   621篇
  1973年   594篇
  1972年   541篇
  1971年   473篇
  1968年   540篇
  1967年   540篇
  1966年   475篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
901.
Although cerebral anoxia is not thought to be responsible for triggering near-death experiences (NDEs), the issue is not so clear in the case of hypercapnia. Detection of normal blood gases in Michael Sabom's (1982) case study seems to be the major reply to suggestions that hypercapnia may have a causal role in NDEs. We argue, however, that routine arterial measures of blood gases are not a reliable indicator of cerebral levels.  相似文献   
902.
The authors present an introductory overview of the history of near-death phenomena, followed by a synopsis of near-death research representative of three historical eras: 1880s–1930; 1930s–1960; and 1960 to the present.  相似文献   
903.
In this article the perspective shifts to the “upstream” end of the agricultural knowledge and information system (AKIS). Because knowledge policy and strategic decision-making are not the prerogative of the public sector, organizations such as cooperative unions and multinational companies are included. After considering the influence of the changing environment on the nature of the AKIS, the role of knowledge management and policy in the emerging knowledge and information market is examined. Special attention is given to public and private R&D. The article then looks where information technology (IT) fits in and what considerations determine strategic investment in IT projects and sustained services. Some of the European experiences with this strategic investment are evaluated.  相似文献   
904.
905.
906.
The statistical simulation program DATASIM is designed to conduct large-scale sampling experiments on microcomputers. Monte Carlo procedures are used to investigate the Type I and Type II error rates for statistical tests when one or more assumptions are systematically violated-assumptions, for example, regarding normality, homogeneity of variance or covariance, mini-mum expected cell frequencies, and the like. In the present paper, we report several initial tests of the data-generating algorithms employed by DATASIM. The results indicate that the uniform and standard normal deviate generators perform satisfactorily. Furthermore, Kolmogorov-Smirnov tests show that the sampling distributions ofz, t, F, χ2, andr generated by DATASIM simulations follow the appropriate theoretical distributions. Finally, estimates of Type I error rates obtained by DATASIM under various patterns of violations of assumptions are in close agreement with the results of previous analytical and empirical studies; These converging lines of evidence suggest that DATASIM may well prove to be a reliable and productive tool for conducting statistical simulation research.  相似文献   
907.
Hardware and software modifications are presented that allow for collection and recognition by a Commodore computer of spoken responses. Responses are timed with millisecond accuracy and automatically analyzed and scored. Accuracy data for this device from several experiments are presented. Potential applications and suggestions for improving recognition accuracy are also discussed.  相似文献   
908.
909.
Pascal routines are described for several real-time operations on Macintosh computers. Methods are presented for millisecond timing and for high-speed transfer of arbitrary bit-image displays to the screen. All routines are based on Toolbox procedures available on virtually all Macintosh computers.  相似文献   
910.
The effects of usage of eight verbal response modes by trainee counsellors during an initial interview were determined by reference to client-perceived rapport. Data on rapport were gathered via a standardized client's minute-by-minute ratings of his experience of rapport on a five-point scale during the interview. A total of ten counselling interviews were conducted, and data were examinedfor overall effects (i.e. during the interview as a whole) and minute-by-minute effects. Restatements, Minimal Encouragers and Verbosity were significantly dafferent in occurrence in high versus low rated interviews. Minute-by-minute data revealed that these overall differences were not consistent at all stages of the interviews. Implications for counsellor training are discussed.  相似文献   
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