全文获取类型
收费全文 | 7225篇 |
免费 | 208篇 |
国内免费 | 4篇 |
出版年
2018年 | 128篇 |
2017年 | 101篇 |
2016年 | 103篇 |
2015年 | 79篇 |
2014年 | 95篇 |
2013年 | 633篇 |
2012年 | 197篇 |
2011年 | 191篇 |
2010年 | 103篇 |
2009年 | 127篇 |
2008年 | 178篇 |
2007年 | 202篇 |
2006年 | 170篇 |
2005年 | 170篇 |
2004年 | 166篇 |
2003年 | 140篇 |
2002年 | 150篇 |
2001年 | 239篇 |
2000年 | 226篇 |
1999年 | 162篇 |
1998年 | 79篇 |
1997年 | 73篇 |
1996年 | 78篇 |
1993年 | 69篇 |
1992年 | 146篇 |
1991年 | 139篇 |
1990年 | 130篇 |
1989年 | 111篇 |
1988年 | 102篇 |
1987年 | 117篇 |
1986年 | 119篇 |
1985年 | 116篇 |
1984年 | 109篇 |
1983年 | 98篇 |
1982年 | 69篇 |
1981年 | 81篇 |
1979年 | 117篇 |
1978年 | 88篇 |
1977年 | 75篇 |
1976年 | 66篇 |
1975年 | 82篇 |
1974年 | 109篇 |
1973年 | 119篇 |
1972年 | 86篇 |
1971年 | 84篇 |
1970年 | 92篇 |
1969年 | 89篇 |
1968年 | 115篇 |
1967年 | 90篇 |
1966年 | 98篇 |
排序方式: 共有7437条查询结果,搜索用时 15 毫秒
121.
Arthur Peacocke 《Zygon》1984,19(4):395-432
Abstract. The basic features of thermodynamics as the "science of the possible" are outlined with a special emphasis on the role of the concept of entropy as a measure of irreversibility in natural processes and its relation to "order," precisely defined. Natural processes may lead to an increase in complexity, and this concept has a subtle relationship to those of order, organization, and information. These concepts are analyzed with respect to their relation to biological evolution, together with other ways of attempting to quantify it. Thermodynamic interpretations of evolution are described and critically compared, and the significance of dissipative structures, of "order through fluctuations," is emphasized in relation both to the evolutionary succession of temporarily stable forms and to kinetic mechanisms producing new patterns. 相似文献
122.
D I Radin 《Perceptual and motor skills》1984,58(3):887-888
A double-blind experiment with 58 adults tested the hypothesis that proximity to sugar reduces human grip strength. An analysis of variance supported the hypothesis. 相似文献
123.
124.
One of the most serious psychosocial problems worldwide is substance abuse because of its repercussions not only on the physical and psychological health of the abuser but also on their relational functioning. Among the well-established therapeutic approaches for the treatment of substance abuse is family therapy, which, in addition to influencing personal variables, promotes changes in family dynamics. The main objective of this study is to review the scientific literature published from 2010 to the present on the efficacy and effectiveness shown by family-based treatment approaches for substance use problems both in adolescent and adult samples. In addition, the effect on secondary variables such as family functioning and behavioral problems is evaluated. The empirical evidence accumulated in the last decade and reviewed in the present study indicates that the incorporation of family members in the treatment of substance abuse produces benefits by diminishing consumption and improving family functioning. Limitations of this study and of the research reviewed are discussed and directions for future research are provided. 相似文献
125.
Gunst Noëlle Pellis Sergio M. Wandia I Nengah Leca Jean-Baptiste 《Animal cognition》2023,26(2):639-654
Animal Cognition - Self-handicapping behaviors evolved as honest signals that reliably reflect the quality of their performers. In playful activities, self-handicapping is described as... 相似文献
126.
Few studies have evaluated best friendship dissolutions and especially the circumstances surrounding the dissolutions. In this exploratory study of young adolescents (N = 273, Mage = 11.83 years; 51% boys), we investigate young adolescents' experiences with two types of best friendship dissolution (complete dissolutions, downgrade dissolutions) and two characteristics of such experiences: initiation status (self- versus friend-initiation) and emotional reactions (degree of happiness, anger, sadness, and embarrassment). We also consider whether these characteristics of best friendship dissolutions are related to psychological difficulties (loneliness, depressive symptoms). Results indicated that most young adolescents perceive their friends initiated their recent complete and downgrade dissolutions. When young adolescents did initiate their complete dissolutions, however, they reported less negative (anger) and more positive (happiness) emotional responses. Initiation status was not related to psychological difficulties, but variability in several types of emotional responses (e.g., embarrassment) was related to variability in loneliness and depressive symptoms. Findings underscore the importance of considering not only the type of dissolution, but also the circumstances surrounding dissolutions, during early adolescence. 相似文献
127.
128.
Factor analysis by generalized least squares 总被引:1,自引:0,他引:1
Aitken's generalized least squares (GLS) principle, with the inverse of the observed variance-covariance matrix as a weight matrix, is applied to estimate the factor analysis model in the exploratory (unrestricted) case. It is shown that the GLS estimates are seale free and asymptotically efficient. The estimates are computed by a rapidly converging Newton-Raphson procedure. A new technique is used to deal with Heywood cases effectively.The work on this project was done when the first author was Research Statistician at Educational Testing Service, Princeton, N. J. The second author was in part supported by a grant from the Research Committee of the University of Wisconsin Graduate School. The authors wish to thank Michael Browne for many helpful comments and Marielle van Thillo for valuable assistance in the numerical computations. 相似文献
129.
130.
A. L. Wilkes P. Lloyd I. Simpson 《Quarterly journal of experimental psychology (2006)》1972,24(1):48-54
An investigation is reported into pausing and grouping during the serial learning of letter strings, when presented randomly by length and when presented in ascending order. Mean pause times for the reading and recall of longer lists were significantly greater than for lists of shorter span due to extended pausing at specific list positions. In general, reading rhythms were duplicated during recall. Subjects were highly consistent in maintaining their level of pause duration across lists and responded to additions in list length by increasing their number of groups, not by increasing group size. Triadic sequences were the most popular form of spontaneous organization. Pausing measures are discussed as indices of organizational strategies. 相似文献