全文获取类型
收费全文 | 54647篇 |
免费 | 2237篇 |
国内免费 | 30篇 |
出版年
2020年 | 671篇 |
2019年 | 817篇 |
2018年 | 1207篇 |
2017年 | 1206篇 |
2016年 | 1256篇 |
2015年 | 819篇 |
2014年 | 1013篇 |
2013年 | 4855篇 |
2012年 | 1850篇 |
2011年 | 2023篇 |
2010年 | 1185篇 |
2009年 | 1108篇 |
2008年 | 1813篇 |
2007年 | 1740篇 |
2006年 | 1563篇 |
2005年 | 1364篇 |
2004年 | 1314篇 |
2003年 | 1185篇 |
2002年 | 1225篇 |
2001年 | 1758篇 |
2000年 | 1680篇 |
1999年 | 1276篇 |
1998年 | 672篇 |
1997年 | 577篇 |
1996年 | 520篇 |
1995年 | 518篇 |
1994年 | 500篇 |
1993年 | 522篇 |
1992年 | 1016篇 |
1991年 | 962篇 |
1990年 | 951篇 |
1989年 | 856篇 |
1988年 | 817篇 |
1987年 | 803篇 |
1986年 | 804篇 |
1985年 | 857篇 |
1984年 | 669篇 |
1983年 | 579篇 |
1982年 | 470篇 |
1979年 | 654篇 |
1978年 | 489篇 |
1976年 | 448篇 |
1975年 | 589篇 |
1974年 | 623篇 |
1973年 | 594篇 |
1972年 | 539篇 |
1971年 | 475篇 |
1968年 | 540篇 |
1967年 | 541篇 |
1966年 | 478篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
281.
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
282.
We investigated in a sample of 75 medical students the hypothesis that higher levels of self-criticism, a major vulnerability factor for depression, are related to retrospective reports of less satisfactory parenting, even when the potentially confounding factors of mood state and social desirability response set are controlled. At each of 2 measurement times, there were significant cross-sectional correlations between parental ratings and both depression and self-criticism, but the associations with self-criticism were no longer significant when depression was controlled. However, even after controlling for the effects of mood state and social desirability, persons with high levels of self-criticism at both measurement points (high trait self-criticism subjects) reported significantly worse relationships with their mothers than did the remaining subjects. They were also more likely to report below average relationships with both parents jointly. 相似文献
283.
This research evaluated the relationship between pain and sleep problems, and the role of pain and sleep problems in depression, in a sample of 242 patients who had been diagnosed with definite or classical rheumatoid arthritis (RA). Patients completed the Pain scale of the Arthritis Impact Measurement Scales, the Center for Epidemiological Studies Depression Scale, and self-reports of sleep disturbance at two data waves over a 2-year interval. Cross-sectional multiple regression analysis revealed that the sleep problems variable was independently associated with depression at Time 1. Longitudinal multiple regression analyses demonstrated that prior pain predicted subsequent adverse changes in sleep problems, whereas sleep problems did not affect pain over time, and prior pain and the interaction of high pain and high sleep problems were independently associated with depression from Time 1 to Time 2. These data suggest that pain may exacerbate sleeping difficulty in RA patients, and that both factors may contribute to depression over time. 相似文献
284.
Z Solomon M Waysman G Levy B Fried M Mikulincer R Benbenishty V Florian A Bleich 《Family process》1992,31(3):289-302
While the long-term effects of combat trauma on veterans have been studied extensively, its impact on veterans' wives has yet to be investigated. This study examined the implications of combat-induced psychopathology--wartime combat stress reaction (CSR) and current posttraumatic stress disorder (PTSD)--in a sample of 205 wives of Israeli combat veterans of the 1982 Lebanon war. Results show that both CSR and PTSD were associated with increased psychiatric symptoms in the wives. In addition, current PTSD was particularly found to contribute to impaired social relations among veterans' wives in a broad range of contexts, from inner feelings of loneliness, through impaired marital and family relations, and extending to the wider social network. Implications of these findings for treatment and further research are discussed. 相似文献
285.
Twenty treated and 18 untreated spider phobics were exposed to a series of 72 slides. Three different categories of slides were used: phobia-relevant slides (spiders), alternative fear-relevant slides (weapons), and neutral slides (flowers). Slides were randomly paired with either a shock, a tone, or nothing at all. Despite the absence of a systematic correlation between slides and outcomes, untreated phobics strongly overestimated the covariation between spider slides and shock. Treated phobics did not show a covariation bias, suggesting that such bias can be modulated by behavioral treatment. In addition, untreated subjects were more confident about their contingency estimates than were treated subjects. The present results fit with earlier studies. 相似文献
286.
When thinking under uncertainty, people often do not consider appropriately each of the relevant branches of a decision tree, as required by consequentialism. As a result they sometimes violate Savage's sure-thing principle. In the Prisoner's Dilemma game, for example, many subjects compete when they know that the opponent has competed and when they know that the opponent has cooperated, but cooperate when they do not know the opponent's response. Newcomb's Problem and Wason's selection task are also interpreted as manifestations of nonconsequential decision making and reasoning. The causes and implications of such behavior, and the notion of quasi-magical thinking, are discussed. 相似文献
287.
Event-related potentials (ERPs), accuracy scores, and reaction times were used to examine the recognition of emotional expressions. Adults and 7-year-old children saw upright and inverted chromatic slides of the facial expressions of happiness, fear, surprise, and anger, and were asked to press a button for either "happy" or "angry" faces. A positive-going waveform (P300) was apparent at parietal scalp (Pz) and at left and right temporal scalp. Although the behavioral data were similar for both children and adults (e.g., both had more difficulty recognizing angry expressions than happy ones, and angry expressions were more difficult to recognize upside-down than were happy faces), the ERPs indicated that children responded differently than adults did to happy and angry expressions. Adults showed greater P300 amplitude to happy faces, while children showed greater P300 amplitude to angry faces. In addition, for adults, but not children, there were greater P300 amplitude responses at right vs. left temporal scalp. 相似文献
288.
Light and Humphreys (1981, Journal of Experimental Child Psychology, 31, 521-530) provided evidence that young children's drawings, despite infrequently showing view-specific occlusion, do systematically reflect spatial relations within an array. The present research tested the hypothesis that young children's preferences for canonical "best views" interact with array-faithful tendencies to increase early uses of occlusion. Forty-three children between 4 and 7 years of age drew arrays like Light and Humphreys' end-to-end alignments, with end-on views of objects in depth, and arrays aligned side-to-side, with canonical side-views of objects in depth. Significantly fewer single-object, view-specific occlusions were produced for end-to-end than for side-to-side alignments. Nevertheless, the former reveal that more children are able to use the vertical dimension to depict multiple objects in depth. Other comparisons suggest an interaction in multiple-object depictions of canonicality with spatial dimension and graphic complexity. 相似文献
289.
This study showed that a means-end relationship between two snacks exerts a negative influence on preference for the means snack in the contingency. Two snacks ranked of approximately equal medium appeal were individually chosen from an array by each of 86 children (ages 4 years, 4 months to 7 years, 2 months). Children were then assigned to a means-end condition (where one snack was eaten as a means of gaining the other), a temporal order control group (where one snack was presented and eaten before the other), or a mere exposure control group (where the children chose the order in which they ate the two snacks). Post-treatment rankings of the snacks showed that children in the means-end group came to devalue the means snack relative to the reward snack, despite the demonstrably equal prior appeal of the two snacks. Children in the temporal order and mere exposure control groups did not come to prefer the two snacks preferentially. Implications of the finding that adults can affect children's preferences by relatively minor variations in the manner of presentation are discussed. 相似文献
290.
The intent of this study is to apply a cross-level design to examine the influence of contextual factors upon individuals' performance. The results support the hypothesis that peer group characteristics predict individual performance beyond individual characteristics. The implications for using a cross-level approach to study the effects of contextual variables on individual-level phenomena are discussed. 相似文献