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   33320篇
  免费   1394篇
  国内免费   15篇
  2020年   370篇
  2019年   394篇
  2018年   622篇
  2017年   597篇
  2016年   631篇
  2015年   432篇
  2014年   595篇
  2013年   2895篇
  2012年   1019篇
  2011年   1121篇
  2010年   634篇
  2009年   733篇
  2008年   1029篇
  2007年   981篇
  2006年   938篇
  2005年   875篇
  2004年   860篇
  2003年   836篇
  2002年   825篇
  2001年   1003篇
  2000年   963篇
  1999年   771篇
  1998年   433篇
  1997年   403篇
  1996年   342篇
  1995年   354篇
  1994年   319篇
  1993年   357篇
  1992年   640篇
  1991年   556篇
  1990年   617篇
  1989年   523篇
  1988年   498篇
  1987年   488篇
  1986年   498篇
  1985年   576篇
  1984年   509篇
  1983年   465篇
  1982年   395篇
  1981年   353篇
  1979年   447篇
  1978年   422篇
  1977年   350篇
  1976年   345篇
  1975年   431篇
  1974年   489篇
  1973年   449篇
  1972年   343篇
  1968年   353篇
  1966年   326篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
921.
Two investigations examine the effect of similarity of sexual attitudes on (a) attraction to a stranger and (b) marital sexual satisfaction. In an experiment using undergraduates, manipulation of subject-stranger similarity in general affective orientation to sexuality affected attraction and other evaluative dependent variables. In the second investigation, married couples revealed sexual attitudes and sexual satisfaction. Husbands and wives were similar (r= 0.58, p < 0.001) in their affective orientations to sexuality. Discrepancy between the partners’ scores predicted sexual dissatisfaction in both partners. In addition, the wife's affective orientation to sexuality predicted more indices of sexual satisfaction and adjustment in both the wife and the husband than did the husband's affective orientation to sexuality. Finally, spouses with a positive affective orientation to sexuality were more accurate when judging their partner's sexual enjoyment, compared to spouses with a negative orientation. The findings have implications for the effects of similarity of attitudes on interpersonal attraction and on relationship quality.  相似文献   
922.
There is growing evidence to suggest that the ways in which people think about their health problems may have significant implications for psychological and physical well-being. This possibility has the greatest consequences for those groups facing health problems on a daily basis, in particular, the elderly. This study examined the role of perceived health barriers and value for health in later life. A Perceived Health Barriers (absent, present) by Health Value (low, medium, high) 2.3 factorial design was analyzed for younger and older seniors on: number of life-threatening diseases, need for health care, and life satisfaction. In addition, a longitudinal design was used to examine the joint roles of perceived health barriers (PHBs) and health value (HV) on mortality. Findings generally indicated that individuals’ PHBs and HV are associated with health-related outcomes; however, the results differed for young and old elders. Among young elders, those with PHBs and those with high HV had the most negati e profile. That is, they had more diseases, higher health care needs, and lower life satisfaction. Among older elders, the findings were more complicated in that the relationship between PHB and the outcomes depended on HV. Overall, the patterns for old elders suggest that perceived health barriers are most relevant among those with medium value for health and least relevant among those with low value for health.  相似文献   
923.
A proximal-distal theoretical framework was developed to examine the multivariate roots of homophobia. Using data from a sample of 288 undergraduates who had participated in a computer-assisted panel study over a three-year period, the effects on homophobia of distal and proximal family factors (e. g., parental education and family environment), distal and proximal individual factors (e. g., personality constructs and current beliefs), and proximal individual-situational factors (e. g., acquaintance with homosexuals) were tested in regression analyses. Both analyses employing sets of variables varying in proximity to the homophobic attitude and hierarchical regression employing variables contributing significantly in each set supported the proposed framework. All sets predicted significantly when regressed separately on homophobia; the sets containing the distal factors contributed most weakly, and the sets containing the proximal factors contributed most strongly. In hierarchical regression analysis, this pattern maintained such that the incremental increase in r2 decreased with the addition of each more distal set, with the most distal factors failing to contribute significantly to the prediction. The importance of study findings for attitude change efforts is discussed.  相似文献   
924.
Child-to-parent transmission of cytomegalovirus may be reduced by increasing protective behaviors (handwashing and glove use) and decreasing risky behaviors (intimate contact between child and parent). This study showed that an educational intervention resulted in increases in reported and objective measures of protective behaviors and decreases in reported risky behaviors. Further study must determine if changes in protective and risky behavior are maintained and prevent cytomegalovirus transmission.  相似文献   
925.
In this paper, we applied the behavioral-economic concept of unit price to the study of reinforcer magnitude in an attempt to provide a consistent account of the effects of reinforcer magnitude on behavior. Recent research in the experimental analysis of behavior and in behavioral pharmacology suggests that reinforcer magnitude interacts with the schedule of reinforcement to determine response rate and total consumption. The utility of the unit-price concept thus stems from its ability to quantify this interaction as a cost-benefit ratio (i.e., unit price = characteristics of the schedule of reinforcement divided by magnitude of reinforcement). Research employing the unit-price concept has shown that as unit price increases, a positively decelerating function exists for consumption (i.e., a function with an increasingly negative slope, when plotted on log coordinates) and a bitonic function exists for response rate. Based on these findings, the present analysis applied the unit-price concept to those studies of reinforcer magnitude and drug self-administration that examined the effects of reinforcer magnitude on response rate using simple schedules of reinforcement (e.g., fixed-ratio schedule). This resulted in three findings: (a) Reinforcer-magnitude manipulations and schedule manipulations interact in a manner that can be quantified in terms of unit price as benefit and cost factors, respectively; (b) different reinforcer-magnitude manipulations are functionally interchangeable as benefit factors in the unit-price ratio; and (c) these conclusions appear warranted despite the differences in reinforcers (food or drug), species (dogs, monkeys, or rats), and schedules (interval or ratio), and despite the fact that these studies were not designed for a unit-price analysis. In methodological terms, these results provide further evidence that employing the unit-price concept is a parsimonious method for examining the effects of reinforcer magnitude. In theoretical terms, these results suggest that a single process may underlie the effect of combined reinforcer-magnitude and schedule manipulations.  相似文献   
926.
Conclusion In contemporary work, the distinction between the proposition expressed by a sentence and its psychological significance is usually motivated by a familiar kind of counterfactual argument; and the discussion of these issues usually centers around the role of external factors in determining the meaning of our words. My primary goal in this paper has been to show that a similar, though not identical, distinction between two aspects of meaning can be developed entirely on the basis of considerations internal to language users — their cognitive limitations. To make this point, I have focused on symbols introduced through stipulative definitions. In a language containing such symbols, certain expressions and their definitional reductions will seem to differ in psychological significance for creatures with limited intellects, and so in any aspect of meaning that is supposed to correlate with psychological significance; but it seems also that there is some important aspect of meaning that they share.I have argued that a distinction in meaning like this — between sense and psychological significance — should be drawn even in the kind of languages of most concern to Frege, and that his failure to do so led to tensions in his thought. Of course, this observation only touches on the many issues involved in interpreting Frege's theory of definition more generally. I have not tried to describe here, for example, the ways in which the weak interpretation of fruitfulness might interact with the more robust interpretation mentioned earlier; I have only mentioned Frege's view on explicative definitions and the paradox of analysis, and failed even to mention either his treatment of contextual definition, or his peculiar objections to conditional definitions. I do want to emphasize, however, that the distinction drawn here is not simply a matter of Frege scholarship, but that it has some contemporary relevance as well. As we have seen, Frege's semantic goals often coincide with our own; and a number of contemporary writers are explicitly concerned, like Frege, to construct a semantic theory that is able to account for differences in meaning among logically equivalent expressions. Any such theorist should recognize a distinction like that drawn here between sense and psychological significance, and should avoid subjecting an account of one notion to constraints appropriate only for the other.  相似文献   
927.
Gustav Shpet,Appearance and Sense: Phenomenology as the Fundamental Science and Its Problems, Trans. Thomas Nemeth (Dordrecht, Boston, London: Kluwer Academic Publishers, 1991). xxxi+189 pages. $94.00. (Page references to this work are given in parentheses in the text.)  相似文献   
928.
Cross-study differences in the contributions of work attitudes to the turnover process led us to (a) estimate the six relations among job satisfaction, organizational commitment, turnover intention/withdrawal cognitions, and turnover using meta-analysis; (b) assess the effects of several psychometric moderators on those relations; and (c) compare the influences of satisfaction and commitment in the turnover process by applying path analysis to the meta-analytic correlations. Based on aggregations involving a total of 178 independent samples from 155 studies, results showed that (a) satisfaction and commitment each contribute independently to the prediction of intention/cognitions; (b) intention/cognitions are predicted more strongly by satisfaction than by commitment; (c) intention/cognitions mediate nearly all of the attitu-dinal linkage with turnover; and (d) attitudinal contributions to the turnover process vary with the use of single- versus multi-item scales, the 9- versus 15-item version of the Organizational Commitment Questionnaire, and turnover intention versus withdrawal cognition scales.  相似文献   
929.
Lever pressing in rats was maintained by continuous and intermittent schedules of food while defecation was monitored. In Experiment 1, reinforcement densities were matched across variable-ratio and variable-interval schedules for three pairs of rats. Defecation occurred in all 3 rats on the variable-ratio schedule and in all 3 rats on the yoked variable-interval schedule. In Experiment 2, fixed-ratio and fixed-interval schedules with similar reinforcement densities maintained lever pressing. Defecation occurred in 3 of 4 rats on the fixed-ratio schedule and in 4 of 4 rats on the fixed-interval schedule. Almost no defecation occurred during continuous reinforcement in either experiment. These results demonstrate that defecation may occur during both ratio and interval schedules and that the inter-reinforcement interval is more important than the behavioral requirements of the schedule in generating schedule-induced defecation.  相似文献   
930.
In November 1990 the National Institute of Mental Health (NIMH) convened a special conference of over 100 scientists and leaders to outline specific strategies and research initiatives that should be developed to implement the recently released National Plan for Research on Child and Adolescent Mental Disorders.Participants included journal editors, educators from psychology and psychiatry, representatives from private foundations, and leaders of research program areas in public funding agencies. Critical knowledge gaps were identified in five areas of child and adolescent psychopathology, including depression, attention deficit hyperactivity disorder, conduct disorder, the anxiety disorders, and the developmental disorders. For each of these areas, special emphasis was placed on developing new ideas and obtaining critical input from other areas of investigation. This report summarizes the identified research gaps and recommends research initiatives to implement the National Plan, as outlined by the conference participants.  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