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   2528篇
  免费   1005篇
  国内免费   32篇
  3565篇
  2018年   29篇
  2017年   33篇
  2016年   33篇
  2013年   168篇
  2012年   64篇
  2011年   89篇
  2010年   121篇
  2009年   189篇
  2008年   114篇
  2007年   117篇
  2006年   85篇
  2005年   87篇
  2004年   96篇
  2003年   88篇
  2002年   61篇
  2001年   120篇
  2000年   52篇
  1999年   78篇
  1998年   77篇
  1997年   53篇
  1996年   88篇
  1995年   70篇
  1994年   77篇
  1993年   71篇
  1992年   86篇
  1991年   91篇
  1990年   76篇
  1989年   77篇
  1988年   62篇
  1987年   47篇
  1986年   41篇
  1985年   33篇
  1984年   32篇
  1982年   40篇
  1981年   26篇
  1980年   26篇
  1979年   26篇
  1973年   32篇
  1972年   44篇
  1971年   42篇
  1970年   27篇
  1969年   29篇
  1968年   57篇
  1967年   38篇
  1966年   48篇
  1965年   40篇
  1964年   81篇
  1963年   73篇
  1962年   49篇
  1961年   38篇
排序方式: 共有3565条查询结果,搜索用时 0 毫秒
151.
The purpose of this investigation was to further define the role of anxiety sensitivity, in relation to physiological arousal and the cognitive perception of anxiousness, as a determinant of anxiety. One hundred and thirty-two undergraduates at an urban university served as subjects. Two physiological measures of arousal and two cognitive measures of anxiety were used following an anxiety inducing task (mental arithmetic). The general expectation, which was supported, was that individual differences in anxiety sensitivity levels are more closely related to subjects' reported anxiousness in stressful conditions than are the actual physiological changes. Additionally, anxiety sensitivity was related to poststress levels of anxiety whereas trait anxiety was only related to pre- and postrelaxation levels of anxiety. Implications of the findings are addressed.  相似文献   
152.
153.
154.
The presence of nonobservational vocabulary is shown to be necessary for wide application of a conservative principle of theory revision.Support for this research was provided by the Office of Naval Research under contract No. N00014-87-K-0401. We thank Daniel Andler and Clark Glymour for helpful discussion.  相似文献   
155.
156.
157.
Abstract: Do memories change as we acquire new information? Recent research on memory distortion using implicit tests along with research using confidence is reviewed and new studies are presented. Two new studies asked misinformed subjects to provide reasons for their answers. In each study 15% to 27% of subjects said they remembered seeing items they had only read about. In another study subjects were asked to identify the source of misleading items they had seen in slides or read in misleading questions. Subjects were more likely to say they had seen in slides something they read about in the questions than they were to confuse information from two nearly identical sets of slides. Recent work shows that, not only is it possible to distort memory for events, it is possible to implant an entire memory for something that never happened. The evidence is now clear that we can become mentally tricked into making large as well as small changes in the way we recall the past.  相似文献   
158.
159.
160.
Pigeons were trained to peck a key on a variable-interval 2-min schedule of food reinforcement. Prior to each session, either 2.0 mg/kg methadone (n = 3), 3.0 mg/kg cocaine (n = 4), or 5.6 mg/kg cocaine (n = 2) was administered. When each pigeon's rate of pecking was stable, a range of doses of the training drug and saline were administered prior to 20-min extinction sessions separated by at least four training sessions. Rate of pecking during these extinction tests was generally an increasing function of dose, with the lowest rates obtained following saline and low doses and the highest rates obtained following doses near the training doses. Dose functions from pigeons trained with 5.6 mg/kg cocaine were steeper than those from pigeons trained with 3.0 mg/kg cocaine. Pigeons trained with methadone or 3.0 mg/kg cocaine were then given discrimination training, in which food reinforcement followed drug administration and 20-min extinction sessions followed saline administration. Rates of pecking under these conditions quickly diverged until near-zero rates were obtained following saline and high rates were obtained following drug. Discrimination training steepened dose functions for the training drugs, and the effects of several other substituted drugs depended on the pharmacology of the training drug. The pigeons trained with 5.6 mg/kg cocaine were tested with d-amphetamine, methadone, and morphine prior to discrimination training. d-Amphetamine increased rates dose dependently, and methadone and morphine did not. The results suggest that discriminative control by methadone and cocaine was established without explicit discrimination training.  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