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   8337篇
  免费   156篇
  国内免费   9篇
  2020年   52篇
  2019年   59篇
  2018年   221篇
  2017年   181篇
  2016年   267篇
  2015年   151篇
  2014年   109篇
  2013年   465篇
  2012年   416篇
  2011年   431篇
  2010年   117篇
  2009年   122篇
  2008年   182篇
  2007年   175篇
  2006年   174篇
  2005年   1437篇
  2004年   774篇
  2003年   552篇
  2002年   241篇
  2001年   112篇
  2000年   86篇
  1999年   85篇
  1998年   82篇
  1997年   47篇
  1996年   55篇
  1995年   50篇
  1994年   59篇
  1992年   78篇
  1991年   109篇
  1990年   106篇
  1989年   91篇
  1988年   65篇
  1987年   88篇
  1986年   75篇
  1985年   69篇
  1984年   56篇
  1983年   60篇
  1982年   46篇
  1981年   48篇
  1979年   70篇
  1978年   54篇
  1977年   44篇
  1975年   68篇
  1974年   66篇
  1973年   61篇
  1972年   53篇
  1971年   49篇
  1970年   44篇
  1968年   43篇
  1967年   45篇
排序方式: 共有8502条查询结果,搜索用时 15 毫秒
51.
A common criticism of iterative least squares estimates of communality is that method of initial estimation may influence stabilized values. As little systematic research on this topic has been performed, the criticism appears to be based on cumulated experience with empirical data sets. In the present paper, two studies are reported in which four types of initial estimate (unities, squared multiple correlations, highestr, and zeroes) and four levels of convergence criterion were employed using four widely available computer packages (BMDP, SAS, SPSS, and SOUPAC). The results suggest that initial estimates have no effect on stabilized communality estimates when a stringent criterion for convergence is used, whereas initial estimates appear to affect stabilized values employing rather gross convergence criteria. There were no differences among the four computer packages for matrices without Heywood cases.  相似文献   
52.
53.
54.
55.
The authors present a short review of the pertinent literature and report on their own neuropsychiatric findings following internal craniocerebral injuries, at the same time drawing attention to the necessity of psychological examination. Statistical comparisons with the international literature are complicated owing to the different classifications used for craniocerebral injuries.  相似文献   
56.
Attributional retraining: a review   总被引:18,自引:0,他引:18  
  相似文献   
57.
This paper reports an experiment testing two hypotheses. The first is that the value or utility associated with a payment to one's self and a payment to a co-worker can be represented as an additive function of a utility for own payment (nonsocial utility) and a utility for the difference between own and other's payment (social utility). The second hypothesis is that changes in the amount of work accomplished by one's self and/or the other should influence the social, but not the the nonsocial utilities. Support for both hypotheses is reported.  相似文献   
58.
A reinforced practice procedure was used to facilitate cooperative behavior in five children, aged 3 to 6 years, during dental treatment. In a multiple baseline design across subjects, the children were rewarded with escape, inexpensive stickers, and praise for cooperative behavior in the presence of the sights, sounds, and some sensations of the dental instruments prior to actual dental treatment. Direct observations of disruptive behavior via a 15-s interval recording system indicated baseline levels as high as 90% were reduced to less than 15% by the final treatment visit. In addition, the procedure was effective in reducing overall heart rate and blood pressure reactivity to dental treatment. All children were rated by the involved dental professionals as more cooperative and relaxed following exposure to reinforced practice.  相似文献   
59.
60.
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