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   62509篇
  免费   2614篇
  国内免费   23篇
  2020年   804篇
  2019年   903篇
  2018年   1297篇
  2017年   1295篇
  2016年   1399篇
  2015年   1008篇
  2014年   1201篇
  2013年   5461篇
  2012年   2227篇
  2011年   2237篇
  2010年   1350篇
  2009年   1377篇
  2008年   1922篇
  2007年   1901篇
  2006年   1715篇
  2005年   1492篇
  2004年   1519篇
  2003年   1446篇
  2002年   1393篇
  2001年   2038篇
  2000年   1887篇
  1999年   1464篇
  1998年   713篇
  1997年   625篇
  1996年   696篇
  1995年   631篇
  1994年   607篇
  1993年   596篇
  1992年   1191篇
  1991年   1090篇
  1990年   1069篇
  1989年   1008篇
  1988年   980篇
  1987年   929篇
  1986年   923篇
  1985年   970篇
  1984年   796篇
  1983年   693篇
  1979年   822篇
  1978年   637篇
  1977年   539篇
  1976年   539篇
  1975年   665篇
  1974年   743篇
  1973年   745篇
  1972年   633篇
  1971年   597篇
  1968年   650篇
  1967年   556篇
  1966年   552篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
931.
In four experiments we examined the effect of an irrelevant drive on classical conditioning with food and water. In the first experiment the irrelevant drive weakened the conditioned response in extinction. In Experiments 2 and 3, this suppressive effect was found also in acquisition. Furthermore, the presence of an irrelevant drive during nonreinforced presentations of the conditioned stimulus was found to protect the conditioned response from extinction. Experiment 4 showed that the depressive effect of the irrelevant drive is manifested only when the relevant drive is present. Taken together, these results suggest that an irrelevant drive can influence conditioned responding by modulating the representation of the unconditioned stimulus.  相似文献   
932.
The results of three different experiments suggested that the relation between an object in the fovea on fixation n and an object subsequently brought into the fovea on fixation n + 1 affects the time to identify the second object. In Experiment 1 we extended previous work by demonstrating that a previously seen related priming object speeded the time to name a target object even when a saccade intervened between the two objects. In Experiment 2 we replicated this result and further showed that the benefit on naming time was due to facilitation from the related object rather than inhibition from the unrelated object. In addition, naming of the target object was much slower in both experiments when there was not a peripheral preview of the target object on fixation n. However, because the effect of the foveal priming object was greater when the target was not present than when it was present, priming did not appear to make extraction of the extrafoveal information more efficient. In Experiment 3, fixation times were recorded while subjects looked at four objects in order to identify them. Fixation time on an object was shorter when a related object was fixated immediately before it, even though the four objects did not form a scene. The size of the facilitation was roughly comparable to that in several analogous experiments where scenes were used. The results suggest that the effects of a predictive scene context on object identification may be explainable in terms of an object-to-object or "intralevel" priming mechanism.  相似文献   
933.
A considerable percentage of depressed patients do not respond to antidepressive treatment. Early indicators of prognosis are needed. The aims of this study are to examine (a) whether the interpersonal behavior of patients and psychiatrist, as assessed by means of direct observation of behavior during a baseline clinical interview, might have predictive value with respect to therapeutic outcome and (b) which predictive potency measures of psychomotor activation, as assessed by less refined methods, such as global clinical judgment, might have. In the analysis used, speech-pause behavior was taken as the basic structure of the interaction. The relations of other behaviors such as looking and hand and head movement with this structure were determined. Evidence is presented that in a group of 31 depressives, improvement after a period of 10 weeks was related to observed behaviors during a baseline interview. The behaviors of the patients are interpreted as relational or nonrelational. The relational behaviors (i.e., looking yesnodding, gesturing) occur less in patients who will improve, whereas the nonrelational behaviors (i.e., intensive body touching, head movements) occur more in these patients. The nonrelational behaviors are presumed to be indicative of the state of arousal. The predictive potency of these variables could not be explained by their relationship with the baseline severity of depression, which in itself also predicted improvement. Moreover, global clinical assessment of psychomotor activation (i.e., retardation and agitation) could not be related to outcome.  相似文献   
934.
The authors review the literature on the relationship between menstruation and crime, focusing upon the methodological limitations of these studies in the broader context of criminological and menstruation research. Based on this review, they conclude: the present state of scientific knowledge is such that it is unknown whether there is an association between any phases of the menstrual cycle and crime; there is no evidence linking fluctuations in reproductive hormones to criminal behavior; and, this lack of scientific knowledge is so glaring that evidence regarding menstruation and crime should not be admissible in criminal trials.  相似文献   
935.
The aetiological antecedents of the Type A pattern have not been studied widely. In the present study the effects of parental rearing practices on the development of Type A pattern were evaluated. Perceived parental rearing style was assessed by the EMBU and Type A pattern by the JAS. Subjects were drawn from a random sample of residents (older than 21 years) of a Dutch community. Results suggested that a significant amount of variance of Type A behaviour can be accounted for by perceived parental characteristics, especially rejection and lack of emotional warmth. It is suggested that lack of emotional warmth and negative evaluation of children by their parents may lead to an internalized maladaptive cognitive set in the children which may be a developmental antecedent for eliciting the competitiveness, achievement striving, and sense of time urgency characteristic of Type A adults.  相似文献   
936.
This study compared the predictive validity of two types of overall assessment center ratings (clinical and mechanical) and two types of performance ratings (supervisor and subordinate). Data were gathered on approximately 50 law enforcement agency managers over a four-year time span. Results indicated that clinical predictions were not significantly better than mechanical ones and that prior performance ratings were better predictors of future performance ratings than were assessment centers. Further, dimension ratings within the assessment center were found to be unrelated to ratings of the same dimensions on the job four years later, supporting the notion of subtle criterion contamination (Klimoski & Strickland, 1977) and raising questions about the central assumptions underlying the assessment center approach.  相似文献   
937.
The present study was conducted to examine the hypothesis that compliant chronically ill patients, typically described as adjusted, reinforce more positive social environments using behavioral controls than noncompliant patients, typically described as maladjusted. Specifically, it is hypothesized that diet-compliant chronic hemodialysis patients emit significnatly more active involvement-in-treatment behaviors and more social behaviors than diet-noncompliant chronic hemodialysis patients. Subjects, who ranged in age from 30 to 77 years, were outpatients at a kidney center. Behavioral observations were conducted to assess the occurrence or frequency of (1) four involvement-in-treatment behaviors that are routinely taught to all patients and (2) two social behaviors, which were patient verbalizations and smiles. The results showed that compliant patients emitted significantly more involvement-in-treatment behaviors and smiles than noncompliant patients. Results support the proposed control framework that compliant, in contrast to non-compliant, chronically ill patients have recourse through positive behavioral controls when adjusting to the stresses of illness. It was proposed that through these controls, compliant patients reinforce positive environments rather than simply respond to life circumstances as given.  相似文献   
938.
One of the more important and emerging fields in which psychologists collaborate with other disciplines is psychoimmunology. Centuries of clinical anecdote and decades of psychosomatic hypotheses have gained credibility in the eyes of the medical establishment—and many patients—by the systematic investigation of mechanisms potentially explaining how events intrapsychic and interpersonal could affect physical disease processes. The central nervous system is connected with the immune system by both neuronal and endocrinological pathways. The immune system has been found to mediate the organism’s response to aberrations of its own normal functions, as well as to invading organisms from without. AIDS, arthritis, asthma, lupus, and herpes are some of the illnesses in which research is demonstrating important relationships among psychosocial and immunological factors and disease course. In this article, we first discuss the immunological apparatus in order to provide a base for subsequent discussions of the effects of stress on immune function. Then we discuss malignant diseases and current evidence that disease course is related to both psychosocial stressors and immune function. We next discuss a model of these interactions, and finally we talk about interventions incorporating psychosocial factors aimed at influencing immune status and, thus, disease course.  相似文献   
939.
Claire M. Renzetti 《Sex roles》1987,16(5-6):265-277
The attitudes of female subjects toward gender roles, gender inequality, and the women's movement were measured using a 24-item attitudinal inventory. Subjects tended to hold nontraditional but only moderately feminist attitudes toward gender roles. They were, however, highly aware of gender inequality and supportive of the women's movement, although they were also reluctant to identify themselves as feminists. T tests revealed that subjects most supportive of feminism were advanced students (juniors and seniors) and students who had personally experienced discrimination. But when personal experience of sex discrimination was controlled for, the strength of the relationships between class level and gender role attitudes, and between class level and support for the women's movement, diminished. Students who had personally experienced sex discrimination are less traditional and more feminist in their gender role attitudes, and show stronger support for the women's movement, regardless of their class level, than students who have not had such experiences. These findings are interpreted and their implications for the future of the women's movement are discussed.  相似文献   
940.
Several theories have been presented that predict differences between women and men in attitudes toward the environment due to differences in sex roles. Research on which these theories can be tested has tended to examine general environmental concern, and the results have generally been weak and inconclusive. Using an approach suggested in the literature, this study examines sex differences in concern and knowledge, using multi-item scales for each, about one environmental issue — acid rain. The results contradict the theories being tested, however: if there is a sex difference, men are found to be more concerned and knowledgeable about the environmental problem.  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