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   28003篇
  免费   919篇
  国内免费   14篇
  28936篇
  2019年   265篇
  2018年   423篇
  2017年   444篇
  2016年   452篇
  2015年   294篇
  2014年   380篇
  2013年   2081篇
  2012年   762篇
  2011年   815篇
  2010年   486篇
  2009年   472篇
  2008年   681篇
  2007年   695篇
  2006年   623篇
  2005年   579篇
  2004年   560篇
  2003年   503篇
  2002年   567篇
  2001年   900篇
  2000年   913篇
  1999年   678篇
  1998年   312篇
  1997年   265篇
  1996年   257篇
  1992年   555篇
  1991年   517篇
  1990年   548篇
  1989年   508篇
  1988年   480篇
  1987年   489篇
  1986年   496篇
  1985年   518篇
  1984年   422篇
  1983年   376篇
  1982年   279篇
  1981年   267篇
  1979年   472篇
  1978年   353篇
  1977年   314篇
  1976年   274篇
  1975年   409篇
  1974年   463篇
  1973年   450篇
  1972年   397篇
  1971年   355篇
  1970年   332篇
  1969年   395篇
  1968年   454篇
  1967年   400篇
  1966年   410篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
982.
983.
An experiment was conducted to relate individual components of the event-related brain potential to specific stages of information processing in a two-choice reaction time (RT) task in a group of undergraduate students. Specifically, the latency of the P300 component and the lateralized readiness potential (LRP) were studied as a function of variations in stimulus degradation and response complexity. It was hypothesized that degrading the stimulus would delay the P300 and LRP to the same extent as RT, and that increasing response complexity would affect RT but not P300 latency. The extant literature did not permit any hypothesis regarding the effect of response complexity on LRP latency. The two task variables were found to have additive effects on RT. As predicted, variations in stimulus degradation influenced the latencies of both components, whereas alterations in response complexity had no effect on P300 latency. A significant new finding was that the onset latency of the LRP remained unchanged across levels of response complexity. The overall pattern of results supports the notion of temporal selectivity of stage manipulations that is derived from discrete stage models of human information processing. Furthermore, these results refine the functional interpretation of the LRP by indicating that within the conceptual framework of a stage model the processes this component indexes succeed the start of response choice but precede the start of motor programming.  相似文献   
984.
985.
This paper considers the question: what becomes of the notion of a logic as a way of codifying valid arguments when the customary assumption is dropped that the premisses and conclusions of these arguments are statements from some single language? An elegant treatment of the notion of a logic, when this assumption is in force, is that provided by Dana Scott's theory of consequence relations; this treatment is appropriately generalized in the present paper to the case where we do not make this assumption of linguistic homogeneity. Several applications of the resulting concept of a heterogeneous logic are suggested, but the main emphasis is on the formal development. One topic touched on is a certain contrast between the boolean and the intensional sentence-connectives in this more general setting.  相似文献   
986.
Latent Structure of the Sources of Mathematics Self-Efficacy   总被引:2,自引:0,他引:2  
General social cognitive theory and its career-specific elaborations posit four primary sources through which self-efficacy beliefs are acquired and modified: personal performance accomplishments, vicarious learning, social persuasion, and physiological states and reactions. We present two studies exploring the dimensionality of these sources within the context of career-relevant mathematics activities. In Study 1, 295 college students completed measures of the source variables. Testing two- through five-factor models, we found strongest support for a four-factor latent structure of the efficacy sources. In Study 2, involving 481 high school students, a five-factor model fit the data well. We also found evidence of a higher order factor structure in both samples. Several directions for further research on the sources of efficacy information are considered, along with implications for career and academic interventions.  相似文献   
987.
Ninety-two dual-wage and 103 single-wage Indian families with a preschool-age child residing in extended and nuclear households provided assessments regarding their beliefs about the division of household chores, financial responsibilities, childcare, and filial obligations. Analysis focused on possible differences in belief structures that may be attributed to the gender of the parent, family structural living arrangement, and maternal employment outside of the home. Husbands and wives did not differ in ideological beliefs on any of the components assessed, but differences did emerge as a function of family structural arrangements and whether or not the wife worked outside of the home. Data are discussed in terms of possible changes in ideological beliefs about family functions and practices and the broader socio-cultural factors operating within Indian society.  相似文献   
988.
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   
989.
In this study, we sequentially administered up to four components of the habit-reversal treatment to 4 children with motor tics within a multiple baseline design. The habit-reversal components included (a) awareness training; (b) awareness training and self-monitoring; (c) awareness training, self-monitoring, and social support; and (d) awareness training, social support, and the use of a competing response. Results demonstrated that the combined use of awareness training, social support, and competing response training was effective in eliminating motor tics in 2 of 4 children, that awareness training alone was effective for 1 child, and that a combination of awareness training and self-monitoring was effective for the 4th child. The treatment and ensuing improvement were found to be socially valid. We discuss possible explanations for these results and recommend directions for future research.  相似文献   
990.
This study builds on previous theory of planned behavior (TPB) studies in which we identified the beliefs and values which predict intention to commit driving violations. Four short experimental videos were developed in order to assess the effectiveness of an intervention grounded in the TPB. Three of the videos featured the major constructs of the TPB model. The fourth video featured anticipated regret, an addition to the TPB model which had previously been shown to add significantly to its predictive performance (Parker, Manstead, & Stradling, 1995). Results indicated that two of the videos brought about statistically significant belief changes with respect to scores on TPB items, and significant changes in general attitudes toward speeding. Discussion centers on the problems encountered in operationalizing the TPB constructs and on the potential of theory-based interventions to induce attitude change.  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