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   22026篇
  免费   918篇
  国内免费   13篇
  2020年   256篇
  2019年   245篇
  2018年   419篇
  2017年   370篇
  2016年   392篇
  2015年   258篇
  2014年   365篇
  2013年   1630篇
  2012年   643篇
  2011年   693篇
  2010年   369篇
  2009年   451篇
  2008年   610篇
  2007年   604篇
  2006年   559篇
  2005年   500篇
  2004年   476篇
  2003年   474篇
  2002年   427篇
  2001年   798篇
  2000年   803篇
  1999年   589篇
  1998年   245篇
  1997年   214篇
  1996年   196篇
  1992年   484篇
  1991年   423篇
  1990年   489篇
  1989年   412篇
  1988年   384篇
  1987年   368篇
  1986年   390篇
  1985年   441篇
  1984年   343篇
  1983年   288篇
  1982年   220篇
  1979年   324篇
  1978年   260篇
  1977年   206篇
  1976年   200篇
  1975年   298篇
  1974年   349篇
  1973年   352篇
  1972年   274篇
  1971年   241篇
  1970年   208篇
  1969年   228篇
  1968年   288篇
  1967年   252篇
  1966年   272篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
Results of 1,579 observations of cars entering or exiting campus parking lots showed direct relationships between seat belt wearing and the intrusiveness of the engineering device designed to induce belt usage, and between device intrusiveness and system defeat. For example, all drivers with working interlocks or unlimited buzzer reminders were wearing a seat belt; but 62% of the systems with interlocks or unlimited buzzers had been defeated, and only 15.9% of the drivers in these cars were wearing a seat belt. The normative data indicated marked ineffectiveness of the negative reinforcement contingencies implied by current seat belt inducement systems; but suggested that unlimited buzzer systems would be the optimal system currently available if contingencies were developed to discourage the disconnection and circumvention of such systems. Positive reinforcement strategies are discussed that would be quite feasible for large-scale promotion of seat belt usage.  相似文献   
992.
Within the context of a prospective longitudinal research design, the structure of personality and initial levels of drug use were used to predict, multivariately, later drug use among male and female adolescents. The findings indicated that personality and belief measures of nonconventionality provide a significant increment in the prediction of later drug use beyond a level achieved by knowing initial usage rates. In addition, other personality and belief measures yield further increments in the prediction of subsequent drug use. Developmentally, the results revealed a differentiation of drug use patterns across the year's time, with one pattern primarily reflecting alcohol use, and a second pattern primarily reflecting use of marijuana and ‘hard’ drugs. While both patterns were related to measures of nonconventionality, certain personality features distinguished between them. Emergent use of marijuana and ‘hard’ drugs was related to depression, mistrust and attractiveness, while emergent alcohol use was related to generosity, ambition, agility and cheerfulness. These results were cross-validated in two samples of subjects. Implications of the findings for adolescent psychosocial development are discussed.  相似文献   
993.
Left-handers with an inverted handwriting posture have been found by Levy and Reid to have relatively bilateral representation of tachistoscopically tested verbal and spatial functions. On the assumption that such bilateral representation is inefficient, it was hypothesized that left-inverted subjects (N = 20) would score lower than left- and right-handers with normal handwriting postures (Ns = 64, 66 respectively) on spatial reasoning. Results were consistent with the hypothesis. Possible alternative explanations and directions for future research are outlined.  相似文献   
994.
Planning: Theoretical considerations and empirical evidence   总被引:1,自引:0,他引:1  
Summary A study of processes rather than of abilities characterizes much of Luria's work on cognitive functions. The three major functional organizations in terms of cognitive functions are: arousal, coding, and planning. Each of these has been described with a special emphasis on planning. Tasks appropriate for demonstrating the processes of planning are discussed and the emergence of a planning factor through factor analytic work has been described. Considerations relating to the independence of planning and coding processes in the context of normal and abnormal development are presented next. Finally, planful behavior as an integral part of purposive behavior in humans is considered in the context of consciousness.  相似文献   
995.
996.
This experiment investigated Allport's (1977) claim that normal subjects can be induced to make semantic errors of the type characterised by “deep dyslexia”. The procedure followed that used by Allport except that a subject based control for the chance level of semantic errors was included. The results replicated the original finding by producing a semantic error rate of 12·7%. It was shown, however, that this rate was not significantly higher than the calculated chance rate of 11·5%. It was concluded, therefore, that the semantic error rates reported by Allport can be accounted for in terms of a guessing artefact and thus they bear no relevance to the problem of deep dyslexia.  相似文献   
997.
A model of childhood hyperkinesis, using the Telomian-beagle hybrid dog, is described, demonstrating the interactions of genetics and separation in the development of this syndrome and in the favorable responses of some of these dogs to amphetamine. This work represents the collaboration of three laboratories, utilizing chiefly methods of inhibitory training. Inducing separation distress enhanced the resistance to inhibitory training and the favorable responses to amphetamine.  相似文献   
998.
Hand differences in the rate and variability of rapid tapping were evaluated for the intertap interval and its constituents-the key depression and key release phases of each tap. To accentuate potential hand differences, only subjects with a clear manual superiority in one hand were included. Relative manual proficiency on Fitts' reciprocal tapping task was used to exclude individuals with less-defined hand superiority or dominance, and to categorize subjects as having a dominant left (n=13) or right (n=11) hand. Analysis of variance indicated the dominant hand to have a shorter average intertap interval and thus a faster tapping rate. This hand difference in rate was found to be significant for the key-depression phase, but not the key-release.phase, of the tap. In each handedness group the dominant hand exhibited less variability in the intertap interval and both constituents. Potential associations of these findings with hemispheric asymmetries in sequential ability are discussed.  相似文献   
999.
A practicing physician reviews the contribution of Jewish ethics, as it relates to the structure of Jewish law, to the issue of abortion. The topics approached include the status of the fetus, the relationship of fetus to mother, abortion and murder, therapeutic abortion, and the rights of the mother. The discussion describes rabbinic answers to abortion requests and is followed by a summary of the Jewish attitudes toward termination of fetal life. An appendix is provided, dealing with central aspects of Jewish ethics, the structure of Jewish law, their relationship, and a note on abortion legislation in Israel.  相似文献   
1000.
The development of sexual identity was studied in 686 individuals, using a fantasy measure of sexual identity that does not depend on learned sex-role stereotypes. The results showed a marked differentiation between the sexes at pre-adolescence, a loss of differentiation during the freshman year of college that most closely resembled the lack of differentiation in sexual identity of preschool children, and a reemergence of a clear sexual identity during the last years of college. Possible biological, social context, and psychodynamic-maturational explanations for this pattern of development are discussed.  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