全文获取类型
收费全文 | 55268篇 |
免费 | 1036篇 |
国内免费 | 8篇 |
专业分类
56312篇 |
出版年
2020年 | 561篇 |
2019年 | 653篇 |
2018年 | 845篇 |
2017年 | 867篇 |
2016年 | 996篇 |
2015年 | 700篇 |
2014年 | 828篇 |
2013年 | 4071篇 |
2012年 | 1550篇 |
2011年 | 1581篇 |
2010年 | 968篇 |
2009年 | 1031篇 |
2008年 | 1383篇 |
2007年 | 1331篇 |
2006年 | 1195篇 |
2005年 | 1078篇 |
2004年 | 1032篇 |
2003年 | 986篇 |
2002年 | 1025篇 |
2001年 | 1614篇 |
2000年 | 1603篇 |
1999年 | 1169篇 |
1998年 | 549篇 |
1997年 | 513篇 |
1992年 | 1028篇 |
1991年 | 991篇 |
1990年 | 956篇 |
1989年 | 938篇 |
1988年 | 900篇 |
1987年 | 847篇 |
1986年 | 880篇 |
1985年 | 961篇 |
1984年 | 795篇 |
1983年 | 732篇 |
1982年 | 548篇 |
1981年 | 565篇 |
1979年 | 860篇 |
1978年 | 620篇 |
1977年 | 566篇 |
1976年 | 566篇 |
1975年 | 733篇 |
1974年 | 854篇 |
1973年 | 902篇 |
1972年 | 761篇 |
1971年 | 715篇 |
1970年 | 658篇 |
1969年 | 697篇 |
1968年 | 854篇 |
1967年 | 782篇 |
1966年 | 748篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
Eugene C. Goldfield 《Developmental Review》1983,3(4):371-404
The ecological thesis of direct realism is used as a framework for examining the development of knowing in human infancy. When information for perceiving is defined ecologically (i.e., relative to the situational context and to the physical dimensions, capabilities, and needs of the perceiver), knowing need not be construed as the act of using representations to give meaning to acts or percepts. Knowing, alternatively, is the act of noticing affordances, situation and perceiverspecific meanings of objects, according to their value to the perceiver for achieving specific goals. Changes with development in infant sensorimotor functioning may, in this view, be explained by a process of increasing economy in noticing potentially available affordances, rather than a process of constructing a representational system for making present something not present. Studies of three infant skills widely attributed to the onset of representation are examined with regard to this ecological thesis. Results indicate that the noticing of affordances is critically involved in each of these skills. 相似文献
992.
Interactions of 16 adults (eight married couples whose youngest child was less than 2 1/2 years old) with a single actor infant, dressed as either a male or a female, were recorded and analyzed in four categories: direction of gaze, facial expression, physical contact with the infant, and toy used. After the interaction period, a 45-minute interview on child rearing was conducted with each member of the couple. Observed interactions were then compared with interview data. The results support previous studies which show that both male and female parents behave differently toward unfamiliar infants on the basis of perceived sex. However, parents, especially mothers, appeared unaware of their differential treatment of male and female infants. These results suggest subtle sex-typing of infants by adults. 相似文献
993.
Valerie Tate Angel C.S.W. Carole Katz C.S.W. Arlene Litwack M.S. Mary Maffia Ph.D. Robert A. Mednick Ph.D. Richard Mingoia C.S.W. Rene Rocha Ph.D. 《Group》1983,7(3):55-61
This paper reflects the working through of a group's fantasy that the deceased group leader wished the group to continue. As in any defense, the fantasy protected members from the pain of the finality of the leader's death. This article reveals the subjective experience concerning the effect of the leader's death on the group and members' intrapsychic struggle to separate and individuate from the deceased leader, while attending to and striving toward the group's continuation. The group's painful and growing individuation enabled the group to follow its own tasks without the spector of the deceased leader. 相似文献
994.
The deterrent effect of capital punishment during the 1950s 总被引:1,自引:0,他引:1
W C Bailey 《Suicide & life-threatening behavior》1983,13(2):95-107
This investigation examines the deterrence hypothesis of an inverse relationship between state execution rates and homicides. Although this question has received some attention in recent studies, the findings of these investigations are mixed. Cross-sectional analyses of states have typically shown execution and homicide rates to be positively associated, while at least two national time-series studies report support for the deterrence hypothesis. To test whether these divergent findings are result of the two different methodologies employed (cross-sectional vs. time-series), a methodology that combines the strengths of each is used in the present study. For the period 1950 to 1960, we examine cross-sectionally for states the relationship between changes in execution rates and changes in murder rates. This analysis does not find support for the deterrence argument for the certainty of the death penalty when a number of models of the execution rate--murder rate relationship are considered, and when a variety of imprisonment and socio-demographic factors are considered as control variables. 相似文献
995.
Patrick C. L. Heaven 《Personality and individual differences》1983,4(6):693-694
In the present study scores on Ray's Directiveness scale were subjected to Varimax rotation. Three factors explaining more than 50% of the variance of authoritarianism were interpreted and labelled Submissiveness, Dominance and Aggressiveness, respectively. Although these are in line with Ray's earlier conception of the nature of authoritarianism and do, to some extent, support other findings, it is suggested that the Directiveness scale be expanded to accommodate more characteristics of authoritarianism such as rigidity, hostility and superstitiousness. 相似文献
996.
Recently reported cases involving the malpractice of psychiatrists have also focused attention on the potential liability for similar acts by clinical social workers. While there is no appellate case authority holding social work clinicians liable for malpractice at this time, the potential for such litigation is enormous. This article explores some of the more common areas of concern and suggests several prophylactic measures that clinicians may employ to safeguard both their professional career and their continued financial independence. 相似文献
997.
This article describes guidance and counseling in multicultural New Zealand as a professional service facing social change and supported by training, research, and a national association. 相似文献
998.
A method for identifying eggs laid by different subsections or individual members of groups of domestic hens is described. Fat-soluble dyes are placed in gelatin capsules and fed to selected birds. These dyes produce discrete colored bands in the yolks of eggs laid by those birds. The presence of dye in eggs can be detected through the shell, and different patterns of rings can be distinguished by boiling and sectioning eggs. Application of the method to other species and other circumstances is considered. 相似文献
999.
A system is decribed that collects visual data using a solid-state photodiode image sensor at rates of up to 600 frames/sec in a binary format suitable for image-analysis techniques. Of particular interest is the system’s ability to analyze high-speed movement of animals without prior modification of the subject (e.g., attachment of lamps or reflectors to the subject). 相似文献
1000.
It is a well documented finding that letter identification may be impaired by the presence of neighboring characters. There is much less agreement about the exact nature of such lateral interference. Evidence has been obtained for feature-specific interference, and even feature-specific facilitation. Santee and Egeth (1980) suggested that feature-specific interference will mainly be observed in data-limited situations where stimuli are presented for short durations and positional uncertainty is involved. They further suggested that interference would be revealed in accuracy rather than latency measures.In our first experiment, similar exposure conditions were used to those suggested by Santee and Egeth. In a second experiment, however, a longer exposure duration was used, and latency measurements were also collected. In a third experiment, positional uncertainty was removed by foveal presentation, and with this high quality stimulus presentation only latency measurements could be obtained.In all these experiments clear evidence for feature-specific interference was found, both in accuracy and latency data, and these results also held up under the detectability/criterion analysis proposed by Estes (1982). From these findings it can be concluded that feature-specific interference occurs under a wide range of conditions, including those representative of normal reading. 相似文献