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   84156篇
  免费   2918篇
  国内免费   42篇
  2020年   799篇
  2019年   975篇
  2018年   2443篇
  2017年   2331篇
  2016年   2153篇
  2015年   1057篇
  2014年   1240篇
  2013年   6380篇
  2012年   2466篇
  2011年   3259篇
  2010年   2297篇
  2009年   1910篇
  2008年   2818篇
  2007年   2917篇
  2006年   1900篇
  2005年   1835篇
  2004年   1749篇
  2003年   1619篇
  2002年   1674篇
  2001年   2385篇
  2000年   2282篇
  1999年   1725篇
  1998年   912篇
  1997年   805篇
  1996年   731篇
  1992年   1454篇
  1991年   1388篇
  1990年   1390篇
  1989年   1281篇
  1988年   1194篇
  1987年   1203篇
  1986年   1250篇
  1985年   1321篇
  1984年   1079篇
  1983年   973篇
  1982年   734篇
  1981年   746篇
  1979年   1100篇
  1978年   835篇
  1976年   732篇
  1975年   987篇
  1974年   1097篇
  1973年   1079篇
  1972年   949篇
  1971年   863篇
  1970年   820篇
  1969年   823篇
  1968年   1058篇
  1967年   998篇
  1966年   928篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
Lewis Henry Morgan never used the term evolution in any of his major sociological works. If he may be labeled an evolutionist, the specificity of his views must be taken into account. The main "evolutionist" issue that concerned him was that of the unity or diversity of the human species. This was an urgent political and theological issue in the America of his day, and it impinged also on research on the American Indians. Morgan's first major study was designed to demonstrate the unity of origin of the American aborigines and their "Asian" origins. His methods were derived from the tradition of Indo-European philology. It was virtually as an afterthought that he added a social evolutionary component to what he conceived of as an exercise in philology. Later he came under the direct influence of the English evolutionists, and this was crucial for the conception of Ancient Society.  相似文献   
994.
Distributions of reinforcers between two components of multiple variable-interval schedules were varied over a number of conditions. Sensitivity to reinforcement, measured by the exponent of the power function relating ratios of responses in the two components to ratios of reinforcers obtained in the components, did not differ between conditions with 15-s or 60-s component durations. The failure to demonstrate the “short-component effect,” where sensitivity is high for short components, was consistent with reanalysis of previous data. With 60-s components, sensitivity to reinforcement decreased systematically with time since component alternation, and was higher in the first 15-s subinterval of the 60-s component than for the component whose total duration was 15 s. Varying component duration and sampling behavior at different times since component transition may not be equivalent ways of examining the effects of average temporal distance between components.  相似文献   
995.
This essay presents the findings from a study of the effect of divorce on spiritual growth among Protestants. Looking at movement in the areas of love of God, self, and others, it shows that the divorce experience can have varying levels of impact which relate at least partially to the traumatic intensity of the experience itself.Excerpted from The Effect of Divorce on Spiritual Growth: A Study in Protestant Spirituality (unpublished thesis), (c) 1984 Jean M. Blomquist. All rights reserved.  相似文献   
996.
Scores on the Beck Depression Inventory (BDI) were periodically obtained from the roommates of college students who exhibited a persistent mild depression over a 3-month period. For comparative purposes, BDI scores were also obtained from roommates of individuals who were transiently depressed and from subjects with nondepressed roommates. In comparison with control subjects, the roommates of persistently depressed persons displayed a progressive increase in BDI score over the course of the study.  相似文献   
997.
998.
We present four cases of Prader-Willi syndrome. Two of them have an abnormality of a chromosome 15, the other both show different chromosomal abnormalities. Translocations or deletions were found recently in the bands 15q11/12 in about 60% of the cases of Prader-Willi syndrome. The consequences for diagnosis, symptomatology and genetic counselling of the syndrome are discussed.  相似文献   
999.
The emergence of oedipal object relations is a crucial stage in the development toward individuated adult mentation, distinguished from early stages of psychic life which are transindividual (as in Kohut's "selfobject transference"). The latter continue to function as deep layers of individual psychic life; but the development of oedipal/postoedipal object relations, and advanced psychic structure and functioning based on it, represents a norm in psychoanalytic psychology and therapy. The poet John Keats's ideas about the formation of the individual "soul" (identity as an individual) by the intervention of "circumstances" are cited to illustrate this aspect of the oedipus complex.  相似文献   
1000.
Two perspectives on the nature of the social group and psychological group formation are discussed. The traditional social cohesion approach traces group formation to processes of interpersonal attraction, while the social identity approach defines the group in cognitive terms and considers identification, or self-categorization, to be the mechanism of psychological group formation. On the basis of an experiment by Turner, Sachdev and Hogg (1983) it is hypothesized that interpersonal attraction (positive or negative) is related to group formation only in so far as it enhances intergroup distinctiveness. This hypothesis is experimentally tested in a 2 × 3 (interpersonal liking/disliking per se versus no explicit categorization/random categorization/criterial categorization on the basis of affect) factorial design employing the ‘minimal group’ paradigm. People who like each other and were not explicitly categorized formed a group. This effect was enhanced by criterial categorization but disappeared when categorization was random. Although the results do not support the hypothesis, they are not explicable in social cohesion terms. A social identity explanation is furnished—attraction influences group formation by acting, under certain specifiable conditions, as a cognitive criterion for common category membership. This explanation is located in current theorizing and is proposed as part of a reconceptualization of the relationship between interpersonal attraction and group formation.  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