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   31744篇
  免费   509篇
  国内免费   6篇
  2023年   67篇
  2022年   61篇
  2021年   122篇
  2020年   218篇
  2019年   254篇
  2018年   3712篇
  2017年   3038篇
  2016年   2537篇
  2015年   426篇
  2014年   403篇
  2013年   1386篇
  2012年   1103篇
  2011年   2847篇
  2010年   2839篇
  2009年   1826篇
  2008年   2203篇
  2007年   2639篇
  2006年   522篇
  2005年   633篇
  2004年   623篇
  2003年   527篇
  2002年   471篇
  2001年   209篇
  2000年   245篇
  1999年   198篇
  1998年   205篇
  1997年   174篇
  1996年   114篇
  1995年   147篇
  1994年   146篇
  1993年   132篇
  1992年   124篇
  1991年   115篇
  1990年   118篇
  1989年   110篇
  1988年   117篇
  1987年   112篇
  1986年   89篇
  1985年   104篇
  1984年   118篇
  1983年   99篇
  1982年   111篇
  1981年   115篇
  1980年   107篇
  1979年   103篇
  1978年   112篇
  1977年   91篇
  1976年   94篇
  1975年   66篇
  1974年   78篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
201.
There have been continuing concerns about the extent to which maternal depression may influence maternal reports of child behavior. To examine this issue, a series of structural equation models of the relationships between maternal depression and errors in maternal reports of child behavior was proposed and tested. These models assumed that (a) maternal depression was unrelated to maternal reporting behavior; (b) maternal depression causally influenced maternal reporting accuracy; (c) maternal depression was correlated with reporting accuracy. These models were fitted to data on maternal depression and multipleinformant (mother, teacher, child) reports of conduct disorder and attention deficit behaviors for a birth cohort of 12 and 13yearold New Zealand children. The results of model fitting suggested the presence of small to moderate correlations (@#@ r=+.13 to+.40) between maternal depression and maternal reporting errors, indicating the presence of a tendency for increasing maternal depression to be associated with a tendency for mothers to overreport child behavior problems. However, independently of any effects of maternal depression on maternal reporting errors there was evidence of small but significant associations (r=.10 to .17; p<.05)between maternal depression and child conduct disorder and attention deficit behaviors.This research was funded by grants from the Health Research Council of New Zealand.  相似文献   
202.
203.
204.
Summary A comparison was made between trajectories of reaches to visual targets by 6-months-old infants, with and without lateral prismatic displacement. In the No Prism condition, the major element of the movement veered towards the target, confirming the results of Mathew and Cook (1990). In the Prism condition, the prism did not affect hand position or movement direction at the beginning of the major element, but a lateral displacement was evident by the end of the element. This is taken as evidence that shifts in trajectory during the element were not due to visual guidance. It is suggested instead that these shifts may reflect correction based upon somatic feedback about position in relation to the visually specified goal of the movement. Evidence that the hand approached the virtual target supports the suggestion that any visual guidance was confined to the approach phase of the reach. Nevertheless, it appears that visual guidance was operating at this stage, since movement direction was displaced away from the virtual target and towards the real target.  相似文献   
205.
206.
The utility of verbal and behavioral assessments of value.   总被引:1,自引:1,他引:0       下载免费PDF全文
Subjects lived in a laboratory apartment for up to 30 days, engaging in ordinary activities such as reading, sewing, and artwork. The amount of time devoted to each activity was recorded and compared with periodic verbal ratings of the amount of time devoted to the activities. The verbal and observational assessments of the time distribution were very similar, but there were some discrepancies. Based on self-reports and on observation of time actually devoted to the activities, contingencies were arranged in which time devoted to one activity produced time available for a second activity. When the contingency relation was based on behavioral assessment, predictions of time redistribution were more accurate than when the relations were based on verbal assessment. The close correspondence between observed distributions of time and verbally assessed distributions was probably due to the well-specified situation and rigorous assessment methods. Contrary to some cognitive-behavioral accounts, the contingency results suggest that verbal assessment is not necessarily preferable to observation when the two make discrepant predictions. It is suggested that verbal reports might be used more often in behavior analysis in place of lengthy or difficult observations, and attention is drawn to a personality model that parallels important components of behavior analysis.  相似文献   
207.
208.

Using a Findley changeover procedure, two groups of rats were exposed to various concurrent variable-time (VT) schedules of milk presentation. The rules governing the operation of the timers for the stimulus events differed for the two groups with resulting differences in the overall degree of changeover responding but not with respect to time allocation measures, which in both cases consisted of undermatching. When an interrupted VT reinforcement timer was reset upon re-entry of that component, the rats tended to emit changeover responses almost exclusively to the more favorable component. When the VT reinforcement timers were left running regardless of which components the rats selected, changeover responses were significantly more frequent and equally distributed among both the more and less favorable components. In comparing the present results with those from a similar procedure in which shock was used (Deluty & Church, 1978), it is apparent that what is basic to choice in concurrent interval schedules is not matching or some mathematical variation of it. Instead, it is a tendency to optimize on the basis of the favorability of the stimulus events and the contingencies regarding how those events are timed and administered.

  相似文献   
209.
210.
The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  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