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881.
In this study, 410 college students completed a survey assessing their personal substance use patterns and sexual behavior and their perceptions of other students' substance use and sexual behavior. Two parallel sets of questions were presented to reflect the two contextual conditions of being drunk or high versus being not drunk or high. Results indicated that number of recent sexual partners and normative perceptions of HIV-risky sexual behavior were the strongest predictors of personal HIV-risky behavior when not drunk or high. HIV-risky behavior when drunk or high was predicted by personal substance use as well as by number of recent partners and normative perceptions of peer sexual behavior. These findings suggest that HIV-prevention programs for college students should aim to correct overinflated perceptions of other students' high-risk sexual behavior.  相似文献   
882.
There is growing evidence that Mexican-American adolescents may be at increased risk for depressive symptoms. We sought to replicate and explain this result in a study of adolescent girls attending an obstetric-gynecologic clinic. Three hundred and four girls of diverse ethnic backgrounds completed measures of depressive symptoms, negative attributional style, and locus of control. Consistent with predictions, we found that Mexican-American adolescent girls reported more depressive symptoms than adolescent girls from other ethnic backgrounds, and that Mexican-American adolescent girls displayed more negative cognitive styles than girls from other ethnic backgrounds. Depression differences appeared to be partly explained by differences in negative cognitive style. Implications of the results for a theory of increased Mexican-American adolescent depression, and for applied work, were discussed.  相似文献   
883.
Obsessions are a key feature of obsessive-compulsive disorder (OCD), and chronic worry is the cardinal feature of generalized anxiety disorder (GAD). However, these two cognitive processes are conceptually very similar, and there is a need to determine how they differ. Recent studies have attempted to identify cognitive processes that may be differentially related to obsessive features and worry. In the current study we proposed that (1) obsessive features and worry could be differentiated and that (2) a measure of the cognitive process thought-action fusion would distinguish between obsessive features and worry, being strongly related to obsessive features after controlling for the effects of worry. These hypotheses were supported in a sample of 173 undergraduate students. Thought-action fusion may be a valuable construct in differentiating between obsessive features and worry.  相似文献   
884.
This study examined the hypothesis that, in schizophrenia, elevated trait social anhedonia (SA) is a stable individual difference, whereas in depression, increased SA is a reflection of a current clinical state that will diminish with recovery. Differences in trait Negative Affect (NA) and Positive Affect (PA) were also examined. Individuals with schizophrenia (n = 55) and depression (n = 34) were evaluated at baseline during hospitalization and compared with nonpsychiatric control participants (n = 41). Participants were assessed again at a 1-year follow-up. At baseline, compared with control participants, individuals with schizophrenia and depression were both characterized by elevated SA, greater NA, and lower PA. In schizophrenic individuals, elevated SA remained stable over the follow-up. However, in recovered depressed patients, SA declined over the follow-up period. Group differences remained in NA and PA over the 1-year follow-up. These results support the view that elevated SA is enduring in schizophrenia but that elevated SA is transiently related to clinical status in depression.  相似文献   
885.
In two experiments we studied developmental changes in reasoning about intensive quantities. In contrast to previous studies, color--an intensive quantity that is readily perceivable--was chosen as stimulus material. Children between 6 and 12 years of age and adults predicted the mixture intensity of pairs of liquids with different intensities of red color, the liquid volumes in the two source glasses either being the same (Experiment 1) or different (Experiment 2). The data show that cognitive averaging in this domain develops late and slowly. An extensitivity bias, a strong tendency to use rules (adding in particular) that hold for extensive but not for intensive quantities, predominated up to the age of 12 years and was not totally absent in adults. Contrary to common expectation, children's use of the correct averaging rule became more likely when an extensive quantity, volume, was also varied and thus the task increased in complexity.  相似文献   
886.
This study investigates the relationship between individual differences and the incidence of workplace aggression in a sample of employees from a transportation company and a public school system. Hierarchical multiple regression analysis indicated that measures of trait anger, attribution style, negative affectivity, attitudes toward revenge, self-control, and previous exposure to aggressive cultures accounted for 62% of the variance in the participants' self-reported incidence of workplace aggression. Further research on workplace aggression is advocated, focusing on the role of individual differences and their interactions with organizational and group-level variables.  相似文献   
887.
This functional MRI study examined how people mentally rotate a 3-dimensional object (an alarm clock) that is retrieved from memory and rotated according to a sequence of auditory instructions. We manipulated the geometric properties of the rotation, such as having successive rotation steps around a single axis versus alternating between 2 axes. The latter condition produced much more activation in several areas. Also, the activation in several areas increased with the number of rotation steps. During successive rotations around a single axis, the activation was similar for rotations in the picture plane and rotations in depth. The parietal (but not extrastriate) activation was similar to mental rotation of a visually presented object. The findings indicate that a large-scale cortical network computes different types of spatial information by dynamically drawing on each of its components to a differential, situation-specific degree.  相似文献   
888.
Participants were asked to generate a single sequence of numbers in between two bounds. By varying the requested sequence length and way in which the question is posed, this paradigm enables assessment of the contributions to central executive functioning of schema, focus of attention, and load. With sequences of three or four numbers, a quarter of the sample failed fully to comply with the instructions. They generated an incorrect number of numbers or went outside the specified bounds. With sequences of six numbers, more than half of the sample infringed one or more of the constraints. Participants consistently generated sequences with particular generic properties. The overall frequency and patterns of infringements suggest that a substantial proportion of participants focused their conceptual attention on sequence content and often neglected the problem of how thelength and boundary constraints were going to be evaluated either before or during response delivery.  相似文献   
889.
890.
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