全文获取类型
收费全文 | 173910篇 |
免费 | 7946篇 |
国内免费 | 157篇 |
出版年
2020年 | 2769篇 |
2019年 | 3436篇 |
2018年 | 3510篇 |
2017年 | 3934篇 |
2016年 | 4602篇 |
2015年 | 3903篇 |
2014年 | 4787篇 |
2013年 | 23396篇 |
2012年 | 4479篇 |
2011年 | 3538篇 |
2010年 | 3851篇 |
2009年 | 4734篇 |
2008年 | 3830篇 |
2007年 | 3334篇 |
2006年 | 3919篇 |
2005年 | 3906篇 |
2004年 | 3417篇 |
2003年 | 3066篇 |
2002年 | 2854篇 |
2001年 | 3458篇 |
2000年 | 3299篇 |
1999年 | 3252篇 |
1998年 | 2815篇 |
1997年 | 2669篇 |
1996年 | 2597篇 |
1995年 | 2420篇 |
1994年 | 2390篇 |
1993年 | 2337篇 |
1992年 | 2700篇 |
1991年 | 2540篇 |
1990年 | 2397篇 |
1989年 | 2299篇 |
1988年 | 2271篇 |
1987年 | 2266篇 |
1986年 | 2282篇 |
1985年 | 2476篇 |
1984年 | 2572篇 |
1983年 | 2346篇 |
1982年 | 2371篇 |
1981年 | 2355篇 |
1980年 | 2198篇 |
1979年 | 2263篇 |
1978年 | 2193篇 |
1977年 | 2167篇 |
1976年 | 1976篇 |
1975年 | 2066篇 |
1974年 | 2121篇 |
1973年 | 2017篇 |
1972年 | 1621篇 |
1971年 | 1548篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
881.
Many studies directed at demonstrating perception without awareness have relied on the dissociation paradigm. Although the logic underlying this paradigm is relatively straightforward, definitive results have been elusive in the absence of any general consensus as to what constitutes an adequate measure of awareness. We propose an alternative approach that involves comparisons of the relative sensitivity of comparable direct and indirect indexes of perception. The only assumption required by the proposed approach is that the sensitivity of direct discriminations to relevant conscious information is greater than or equal to the sensitivity of comparable indirect discriminations. The proposed approach is illustrated through an evaluation of Avant and Thieman’s (1985) recent claim that an indirect measure of perception based on judgments of apparent visual duration provides a more sensitive indicator of perception than does a direct measure based on forced-choice recognition. Contrary to this claim, when direct and indirect indexes are measured under comparable conditions, an indirect measure based on judgments of perceived duration provides a less sensitive index of perceptual processing than do comparable direct measures. The proposed approach provides a general conceptual/methodological framework for using the dissociation paradigm in studies directed at establishing unconscious processes. 相似文献
882.
The present study examined the relationship between adolescents' attitudes toward suicide and their psychosocial background. It also evaluated the association between attitudes toward suicide and the subjects' own suicidal tendencies. A questionnaire assessing these issues was administered to 525 Israeli adolescents. Results indicated that significantly more females, nonreligious adolescents, those exposed to suicidal behavior, and those with increased suicidal risk held more accepting attitudes. Ethnic origin, socioeconomic status, and living in intact/nonintact families were not associated with adolescents' attitudes toward suicide. 相似文献
883.
Differences in school behavior and achievement between students from intact, reconstituted, and single-parent families were analyzed. Students from intact two-parent families had fewer absences and tardies, higher grade point averages, and fewer negative and more positive teacher behavioral ratings than did those from reconstituted and single-parent families. 相似文献
884.
885.
Use of approximate weights would greatly simplify decision analysis under certainty since detailed weight elicitation could be avoided. This paper examines the degree to which rank order information about weights can be used to identify a best alternative, or falling uniqueness prescribes an easily implemented rule for selecting a ‘best’ alternative. The prescribed rule uses as weights the centroid of the feasible region defined by the rank order information. In conjunction with the rule, the value of the rank order information can be determined using an ‘expected gain from weight precision’ (EGWP) measure, analogous to ‘expected value of perfect information’ in decision analysis under uncertainty. 相似文献
886.
The main issue of this paper concerns the mediating role of risk appraisal in the relation between past and future behavior. We expected previous risky behavior to heighten risk appraisal, which, in turn, should stimulate preventive behavior. Results ofthree tests of this mediation hypothesis showed that past behavior was strongly related to future behavior; people who behaved hazardously in the past indicated that they tend to do so in the future. Generally, the expected relation between past behavior and risk appraisal was supported. More risky behavior in the past was associated with a heightened risk appraisal. Results also indicate a relation between risk appraisal and future behavior, but in the opposite direction as predicted. Heightened risk appraisal was related to increased levels of risk in future behavior. When predicting future behavior by both risk appraisal and past behavior the effect of risk appraisal on future behavior disappeared, while past behavior remained a strong predictor of future behavior. In a few cases risk appraisal still predicted future behavior when past behavior was controlled for. Unfortunately, these cases showed the opposite relation; i.e., heightened risk appraisal was related to more risky future behavior. Implications of these findings for research on the role of risk appraisal will be discussed. 相似文献
887.
A series of focus group interviews was used to identify major sources of stress and coping responses of Grade 10 students. Relationships with parents and family, work, and lack of money were found to be important sources of stress. Major coping responses included substance use and diversionary activities. Differences between academic streams (tracks) in sources of stress and coping responses were examined. 相似文献
888.
To study malevolent representations, earliest memories were reliably coded on scales of affect tone. Ss were diagnosed with borderline personality disorder: 31 without and 30 with concurrent major depression. Nonborderline comparison subjects had either major depressive disorder (n = 26) or no psychiatric diagnosis (n = 30). Borderline subjects were discriminated from comparison subjects by their more malevolent representations; they more frequently produced memories involving deliberate injury; and they portrayed potential helpers as less helpful. Results suggest the diagnostic significance of malevolent representations, which need to be explained by any theory of borderline personality disorder. 相似文献
889.
Eighty-two women, presenting as normal-weight bulimics, obese binge eaters, social phobics, and individuals with panic disorder, were compared on anxiety, depression, and substance abuse. All were administered the Anxiety Disorder Interview Schedule-Revised and completed the Michigan Alcohol Screening Test, Drug Abuse Screening Test, and Self-Consciousness Scale. A striking proportion of eating disorder subjects were comorbid for one or more anxiety disorders, the most frequent diagnoses being generalized anxiety disorder and social phobia. The results suggest that the place of anxiety in bulimia nervosa goes beyond that discussed within the context of the anxiety reduction model. Conflicting comorbidity findings among this and prior investigations are noted, however, and discussed in terms of the issue of differential diagnosis between eating and anxiety disorders. 相似文献
890.
J M Gold C Randolph C J Carpenter T E Goldberg D R Weinberger 《Journal of abnormal psychology》1992,101(3):487-494
Effortful and automatic memory task performances were examined in 36 schizophrenic patients and 18 normal control Ss. Tasks included free recall, recognition, and frequency estimation. Patients demonstrated impairment in recall, in recognition, in semantic encoding, and in frequency estimation. Deficits were observed across tasks despite differences in attentional demands. The results suggest a basic compromise of memory function, which is consistent with recent neuroimaging evidence of structural or physiological abnormalities in frontal and temporal lobe structures in schizophrenia. 相似文献