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   48243篇
  免费   850篇
  国内免费   3篇
  49096篇
  2020年   548篇
  2019年   677篇
  2018年   942篇
  2017年   986篇
  2016年   1021篇
  2015年   715篇
  2014年   861篇
  2013年   3619篇
  2012年   1546篇
  2011年   1564篇
  2010年   1013篇
  2009年   932篇
  2008年   1390篇
  2007年   1376篇
  2006年   1216篇
  2005年   1077篇
  2004年   1003篇
  2003年   947篇
  2002年   982篇
  2001年   1504篇
  2000年   1429篇
  1999年   1078篇
  1998年   472篇
  1997年   447篇
  1995年   438篇
  1993年   427篇
  1992年   905篇
  1991年   838篇
  1990年   876篇
  1989年   776篇
  1988年   811篇
  1987年   752篇
  1986年   754篇
  1985年   698篇
  1984年   648篇
  1983年   585篇
  1982年   458篇
  1979年   698篇
  1978年   482篇
  1977年   431篇
  1975年   577篇
  1974年   635篇
  1973年   680篇
  1972年   534篇
  1971年   514篇
  1970年   458篇
  1969年   519篇
  1968年   624篇
  1967年   546篇
  1966年   482篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
This research investigated the buffering role of social support in the relationship of work load to both tension-anxiety and coping for police radio dispatchers ( N = 60). Each dispatcher was observed throughout an entire 8-hour work shift by a trained observer. Objective load consisted of the hourly rate of incoming telephone calls, police radio transmissions, and face-to-face or written communications from superiors, co-workers, and others. At the end of each shift, measures were taken of dispatchers' perceived load, felt tension-anxiety, and coping actions. Hierarchical regression revealed that support from superiors moderated the effects of both objective and perceived loads; no main effects of support were found. Statistically significant interactions confirmed the hypothesized buffering role of support: under high perceived load, dispatchers with high social support engaged in more coping actions and felt less tension-anxiety than did low-support dispatchers. No differences were found when perceived load was low. Support also buffered effects of objective load on tension-anxiety but not on coping.  相似文献   
42.
W Lüders 《Psyche》1988,42(3):216-220
  相似文献   
43.
44.
45.
46.
47.
The IES Arrow-Dot was administered to 41 cocaine detoxification patients. This group's scores indicated lower ego functioning and higher impulsivity and superego functioning than other clinical samples. No significant differences were noted between the Arrow-Dot scores of patients who successfully completed the program and those who did not.  相似文献   
48.
49.
We obtain in this paper a representation of the formulae of extensions ofL by generalized quantifiers through functors between categories of first-order structures and partial isomorphisms. The main tool in the proofs is the back-and-forth technique. As a corollary we obtain the Caicedo's version of Fraïssés theorem characterizing elementary equivalence for such languages. We also discuss informally some geometrical interpretations of our results.  相似文献   
50.
Multiunit activity (MUA) was recorded chronically in the hippocampus (CA3) and the medial geniculate body (mMG) during habituation to a tone followed by conditioning (tone paired with footshock) or pseudoconditioning (tone/footshock unpaired) in rats previously trained in a lever-pressing for food task (VI 60). In the conditioned group pairing tones with footshocks rapidly induced an increase in the initial CS-evoked response in the mMG, followed by the emergence of a hippocampal response and a marked conditioned suppression of lever-pressing to the tone. In contrast, in the pseudoconditioned group, the stimulus induced only transient cellular changes in the hippocampus and in the mMG, while no behavioral suppression to the tone could be seen. Moreover, presentations of the CS 45 days later induced multiunit and behavioral responses in both structures, only in the conditioned group. These results are used for discussion of the role of learning-induced changes in the sensory structure (mMG) as compared with changes in an associative structure (hippocampus), during acquisition and retention of a conditioned response.  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