全文获取类型
收费全文 | 54087篇 |
免费 | 1015篇 |
国内免费 | 8篇 |
专业分类
55110篇 |
出版年
2020年 | 526篇 |
2019年 | 640篇 |
2018年 | 879篇 |
2017年 | 876篇 |
2016年 | 967篇 |
2015年 | 660篇 |
2014年 | 821篇 |
2013年 | 3964篇 |
2012年 | 1512篇 |
2011年 | 1549篇 |
2010年 | 995篇 |
2009年 | 1018篇 |
2008年 | 1380篇 |
2007年 | 1341篇 |
2006年 | 1233篇 |
2005年 | 1065篇 |
2004年 | 1056篇 |
2003年 | 999篇 |
2002年 | 1029篇 |
2001年 | 1584篇 |
2000年 | 1571篇 |
1999年 | 1204篇 |
1998年 | 548篇 |
1997年 | 543篇 |
1995年 | 528篇 |
1992年 | 1033篇 |
1991年 | 974篇 |
1990年 | 936篇 |
1989年 | 897篇 |
1988年 | 899篇 |
1987年 | 815篇 |
1986年 | 877篇 |
1985年 | 889篇 |
1984年 | 760篇 |
1983年 | 699篇 |
1982年 | 538篇 |
1979年 | 828篇 |
1978年 | 629篇 |
1977年 | 568篇 |
1976年 | 584篇 |
1975年 | 662篇 |
1974年 | 815篇 |
1973年 | 878篇 |
1972年 | 704篇 |
1971年 | 666篇 |
1970年 | 610篇 |
1969年 | 651篇 |
1968年 | 807篇 |
1967年 | 729篇 |
1966年 | 719篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
We distinguish three different readings of the intuitionistic notions of validity, soundness, and completeness with respect to the quantification occurring in the notion of validity, and we establish certain relations between the different readings. For each of the meta-logical notions considered we suggest that the most natural reading (which is not the same for all cases) is precisely the one which is required by the recent intuitionistic completeness theorems for IPC.This paper was partly written while the first author, H. C. M. de Swart, was a Visiting Fellow at Princeton University for the academic year 1976–1977. This opportunity was given to him by the Niels Stensen Stichting in Amsterdam, the department of philosophy of the Catholic University in Nijmegen and by Princeton University. He is happy to express his appreciation for that opportunity. 相似文献
942.
943.
Although performance expectancies have been shown to be important mediators of achievement behavior, few specific determinants of personal expectancies have been identified, the ecological validity of previous results is limited, and factors influencing group performance expectancies have not been determined. Therefore, the purpose of this field study involving 11- and 12-year-old male soccer players was twofold. First, we examined specific intrapersonal and situational factors influencing players' pregame personal and team performance expectancies. Second, we investigated the effects of winning and losing a competitive soccer game on players' postgame team expectancies involving a hypothetical rematch with the identical opponent. The pregame findings revealed that (a) the intrapersonal factors of ability and self-esteem were related to personal performance expectancies while competitive trait anxiety was not, and (b) the situational factors of past win-loss record and a prior game win or loss against the same opponent influenced team performance expectancies. The postgame findings revealed that future expectancies were affected by the interactive effects of game win-loss and self-esteem. 相似文献
944.
Rats were trained to bar-press for water in the presence of a simultaneous compound tone-light stimulus using a discrete-trial procedure. Different groups were given between 300 and 3900 trials. When subsequently tested in extinction, all rats showed consistent levels of responding to the compound stimulus but responding to the tone and light components declined as a function of number of training trials. This is a demonstration of spontaneous configuring. Two other experiments showed that with similar procedures generalization from a component of the training stimulus to other values on the same continuum decreases with increased training with the compound stimulus. It was concluded that configuring and generalization from a single stimulus involve the same processes. 相似文献
945.
The effects of modifying consummatory behavior on the topography of the autoshaped pecking response in pigeons 总被引:1,自引:1,他引:0
下载免费PDF全文

The autoshaped responses of two debeaked pigeons that had developed modified eating behavior were compared to the autoshaped responses of three control subjects that ate grain normally. The control subjects exhibited keylight responding that was judged normal by two independent raters. The debeaked subjects pecked the key and ate grain with both normal and modified responses. The results of this study demostrate that an autoshaping procedure using grain as an appetitive stimulus may be used to establish a response that is not biologically preorganized. 相似文献
946.
Separate factor analyses of responses to the Tennessee Self-concept Scale using item and scale data are reported for a sample of 255 disabled veterans. A global self-satisfaction factor and several subsidiary factors roughly approximate the external dimension of the scale. The internal dimension interacts with the external one in defining several factors but does not emerge as an independent dimension. Scale data yield a self-esteem factor incorporating both external and internal scales and a self-concept conflict-integration factor. The evidence supports the external dimension more than the internal dimension. The findings are consistent with previous studies that have not validated the two-dimensional design of the scale. 相似文献
947.
C E Sluzki 《Family process》1983,22(4):469-476
Therapeutic modalities centered in interpersonal processes, in structural phenomena, and in reality constructions--the three care orientations in the field of family therapy--are here defined as mutually nonexclusive "translations" of the systemic paradigm into clinical practice. This definition does not attempt to blur the distinctions among these models but seeks to show their common denominator and thus expands the conceptual and clinical repertoire of the systems-oriented family therapist. 相似文献
948.
949.
A framework for assessing multiple levels of the family system by using multiple methodologies is proposed in this paper. This approach for measuring family phenomena is referred to as Multisystem-Multimethod (MS-MM) family assessment. Ideas from systems theory, measurement theory, and clinical application are used to describe the measurement strategy. A clinical case example is offered illustrating one way in which a MS-MM procedure can be implemented with families. Several currently available assessment tools are utilized to assess the individual, marital, and family levels of the family system. This diversity of measurement techniques provides convergent and divergent information within and across system levels. An MS-MM procedure has the capacity to assess the wholistic qualities of systems as well as specific issues within the boundaries of particular family subsystems. 相似文献
950.
JOHN W. MYERS JETTIE McWILLIAMS JOHN FLANDERS JERALDINE KOHUT 《Journal of Employment Counseling》1983,20(2):51-60
This project's goals were to sensitize job service counselors to the needs and employment problems of older rural job-seekers and to develop a model in-service program. 相似文献