全文获取类型
收费全文 | 35584篇 |
免费 | 1440篇 |
国内免费 | 10篇 |
专业分类
37034篇 |
出版年
2020年 | 336篇 |
2019年 | 485篇 |
2018年 | 632篇 |
2017年 | 656篇 |
2016年 | 680篇 |
2015年 | 475篇 |
2014年 | 619篇 |
2013年 | 2719篇 |
2012年 | 1112篇 |
2011年 | 1173篇 |
2010年 | 693篇 |
2009年 | 675篇 |
2008年 | 1007篇 |
2007年 | 1015篇 |
2006年 | 946篇 |
2005年 | 876篇 |
2004年 | 847篇 |
2003年 | 767篇 |
2002年 | 790篇 |
2001年 | 1063篇 |
2000年 | 971篇 |
1999年 | 750篇 |
1998年 | 437篇 |
1997年 | 364篇 |
1996年 | 335篇 |
1992年 | 581篇 |
1991年 | 561篇 |
1990年 | 544篇 |
1989年 | 566篇 |
1988年 | 563篇 |
1987年 | 517篇 |
1986年 | 538篇 |
1985年 | 594篇 |
1984年 | 486篇 |
1983年 | 466篇 |
1982年 | 389篇 |
1981年 | 361篇 |
1979年 | 544篇 |
1978年 | 413篇 |
1976年 | 385篇 |
1975年 | 448篇 |
1974年 | 507篇 |
1973年 | 527篇 |
1972年 | 412篇 |
1971年 | 384篇 |
1970年 | 380篇 |
1969年 | 410篇 |
1968年 | 488篇 |
1967年 | 425篇 |
1966年 | 423篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
161.
D. E. McMillan PhD. 《Integrative psychological & behavioral science》1988,23(2):57-66
Pigeons were trained to acquire a new four-response position sequence each day by pecking three response keys in a predetermined order. The key color varied after each correct response prior to food delivery. Acute administration of Γ9-tetrahydrocannabinol (Δ9-THC) up to a dose that completely eliminated responding, had no effect on total acquisition errors, or on within session patterns of error elimination. Chronic administration of Δ9-THC (3–10 mg/kg/day), either before or after the session for 4–7 weeks, also did not affect these error measures, although rates of responding were markedly suppressed and at times no responding occurred Discontinuation of Δ9-THC administration for periods of 4–6 weeks also was without effect on errors. These experiments suggest that neither acute nor chronic Δ9-THC produce specific effects on the repeated acquisition of serial position responses in pigeons. 相似文献
162.
This study investigated social sensitivity and self-concept in students with learning disabilities (LD) and their non-learning-disabled (non-LD) peers. Thirty students each from public junior and senior high schools and a community college participated in the study; at each grade level, half were identified as learning disabled and half experienced no learning problem. Students were individually assessed in 30-minute interviews for their accuracy in interpreting the thoughts and feelings of actors in tape-recorded stories depicting two adults in happy angry, anxious, and sad interactions. A questionnaire assessing four dimensions of self-concept in learning situations (motivation, task orientation, problem-solving ability, and class membership) was also administered. LD students at all grade levels were significantly less accurate at interpreting social situations than were their non-LD peers, and had significantly lower self-concepts. These results support the need for remediation efforts specifically aimed at social skills for overcoming social deficits in adulthood. 相似文献
163.
164.
165.
This paper suggests that aspects of paranoid character are structured around fantasies of magical and concrete connectedness to objects; these fantasies serve to avoid the terrors of object inconstancy. The authors describe how these fantasies are expressed in the psychoanalytic situation and explore their relation to common paranoid phenomena. The paranoid person must maintain these fantasies of connectedness at all cost or risk experiencing unbearable indifference between self and object. Paradoxically, the sacrifice of self and object boundaries inherent in these fantasies makes object constancy even more difficult to achieve because of the secondary defensive use of anger mobilized to protect the boundaries of the self. 相似文献
166.
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
167.
Twenty depressed patients with major depressive disorder, 20 nondepressed matched control subjects, and 17 patients with anxiety disorders were compared in different measures of social problem solving. Problem solving was assessed with the Means-Ends Problem-Solving Test (Study 1), the solution of personal problems, and a problem-solving questionnaire (Study 2). Results showed that, as predicted, depressed subjects suffered from a deficit in problem solving in all three measures. The majority of these deficits were also displayed by the clinical control group rather than being specific to a diagnosis of depression. However, depressed subjects produced less effective solutions than did normal and clinical control subjects. The results suggest that depressed and anxious patients may have difficulties at different stages of the problem-solving process. 相似文献
168.
To test Coyne's (1976b) theory of depression, students' levels of depressive symptoms, reassurance seeking, and self-esteem were assessed at Time 1, and their same-gender roommates' appraisals of them were assessed 5 weeks later. Mildly depressed students engaged in the type of reassurance seeking described by Coyne. Among men, but not women, mildly depressed students were rejected if they strongly sought reassurance and had low self-esteem but not if they did not seek reassurance or had high self-esteem. Although induction of depressed symptoms in roommates did occur, this contagion effect did not account for the depression-rejection relationship. The prediction that unsupportive, intolerant, or unempathic others would be particularly likely to respond with rejection to reassurance-seeking depressed students with low self-esteem received partial support. Implications for future work on the interpersonal aspects of depression are discussed. 相似文献
169.
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
170.
Predictors and consequences of childhood depressive symptoms: a 5-year longitudinal study. 总被引:31,自引:0,他引:31
A 5-year longitudinal study investigated the interrelationships among children's experiences of depressive symptoms, negative life events, explanatory style, and helplessness behaviors in social and achievement situations. The results revealed that early in childhood, negative events, but not explanatory style, predicted depressive symptoms; later in childhood, a pessimistic explanatory style emerged as a significant predictor of depressive symptoms, alone and in conjunction with negative events. When children suffered periods of depression, their explanatory styles not only deteriorated but remained pessimistic even after their depression subsided, presumably putting them at risk for future episodes of depression. Some children seem repeatedly prone to depressive symptoms over periods of at least 2 years. Depressed children consistently showed helpless behaviors in social and achievement settings. 相似文献