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181.
182.
This article examines whether various cognitive abilities are associated with symptoms of ADHD. Cognitive ability is conceptualized using Cattell-Horn-Carroll (CHC) theory as measured using the Woodcock-Johnson Tests of Cognitive Ability (3rd ed.). This article also examines whether test session behavior mediates the association between cognitive ability and ADHD. Participants are children ages 6 to 12 with (n= 33) and without (n= 19) ADHD. Results show that inattentive symptoms of ADHD are significantly related to the CHC ability of processing speed above and beyond the effect of test session behavior. Symptoms of ADHD (both inattention and hyperactivity/impulsivity) are also significantly associated with visual spatial processing, but this is completely mediated by test session behavior. It is concluded that inattentive symptoms of ADHD are associated with slower processing speed and that this relationship is not explained by test session behavior.  相似文献   
183.
Levine SR 《CNS spectrums》2005,10(7):567-578
Blood disorders have been implicated in approximately 5% to 10% of ischemic stroke, with an increased frequency in younger patients. Most disorders are associated with an increased thrombotic tendency and, therefore, an increased risk of ischemic stroke. Less commonly, a bleeding diathesis may predispose a patient to intracranial hemorrhage. While many conditions predisposing to thrombosis have been associated with stroke, there are relatively few prospective, epidemiological studies addressing hypercoagulable states and arterial stroke compared with the number of studies on the genetic thrombophilias, which are predominantly associated with venous thrombosis. When ordering tests of coagulation in stroke patients, one should keep in mind whether the results will influence therapy and/or patient outcome. It is generally not advocated to screen all stroke patients for a "hypercoagulable workup". Typically, patients to be screened for coagulation defects will have a prior history of one or more unexplained thromboembolic events. The yield for diagnosing a hypercoagulable state is typically greatest for young stroke patients or those with a family history of thrombosis and who have no other explanations for their stroke (cryptogenic stroke). The yield in typically low in unselected ischemic stroke patients and older patients. Treatment of a first stroke with a documented hypercoagulable state is typically long-term or indefinite duration warfarin, although there is a paucity of clinical trial data supporting this clinical approach.  相似文献   
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Studies of great apes have revealed that they use manual gestures and other signals to communicate about distal objects. There is also evidence that chimpanzees modify the types of communicative signals they use depending on the attentional state of a human communicative partner. The majority of previous studies have involved chimpanzees requesting food items from a human experimenter. Here, these same communicative behaviors are reported in chimpanzees requesting a tool from a human observer. In this study, captive chimpanzees were found to gesture, vocalize, and display more often when the experimenter had a tool than when she did not. It was also found that chimpanzees responded differentially based on the attentional state of a human experimenter, and when given the wrong tool persisted in their communicative efforts. Implications for the referential and intentional nature of chimpanzee communicative signaling are discussed.  相似文献   
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Contemporary cognitive models of obsessive-compulsive disorder emphasize the importance of various types of dysfunctional beliefs, such as beliefs about inflated responsibility, perfectionism and the importance of controlling one's thoughts. These beliefs have been conceptualized as main effects, each influencing obsessive-compulsive symptoms independent of the contributions of other beliefs. It is not known whether beliefs interact with one another in their influence on obsessive-compulsive symptoms. To investigate this issue, data from 248 obsessive-compulsive disorder patients were analyzed. Dependent variables were the factor scores on the 4 Padua Inventory subscales. Predictor variables were the factor scores from the 3 factors (inflated responsibility, perfectionism and controlling one's thoughts) of the Obsessive Beliefs Questionnaire and their 2- and 3-way interactions. Regression analyses revealed significant main effects; in almost all analyses one or more of inflated responsibility, perfectionism, and controlling one's thoughts factors predicted scores on the Padua factors even after controlling for general distress. There was no evidence that beliefs interact in their effects on obsessive-compulsive symptoms, thereby providing a relatively unusual instance in which a simpler explanation (main effects only) is just as powerful as a more complex model.  相似文献   
188.
Exposure to media images of thin-and-beautiful women negatively affects the body image and mood states of young women. However, not all women are equally susceptible to these effects. The present experimental investigation with 123 young college women evaluated the moderating effects of the extent of internalization of media ideals. It also examined the preventative impact of two brief interventions (i.e., media literacy information with and without a dissonance-induction procedure). Results indicated that relative to a control group, the exposure to thin-and-beautiful media images adversely influenced the state body image of participants with high internalization levels. Media-literacy psychoeducation prior to the media exposure prevented this adverse effect. Adding a pre-exposure dissonance-induction procedure did not significantly enhance the preventative effects relative to psychoeducation alone. These results and their implications for the treatment and prevention of body image disturbances are discussed in the context of the empirical literature on the media's effects on body image.  相似文献   
189.
This study examines the relationship between psychosocial and study skill factors (PSFs) and college outcomes by meta-analyzing 109 studies. On the basis of educational persistence and motivational theory models, the PSFs were categorized into 9 broad constructs: achievement motivation, academic goals, institutional commitment, perceived social support, social involvement, academic self-efficacy, general self-concept, academic-related skills, and contextual influences. Two college outcomes were targeted: performance (cumulative grade point average; GPA) and persistence (retention). Meta-analyses indicate moderate relationships between retention and academic goals, academic self-efficacy, and academic-related skills (ps =.340,.359, and.366, respectively). The best predictors for GPA were academic self-efficacy and achievement motivation (ps =.496 and.303, respectively). Supplementary regression analyses confirmed the incremental contributions of the PSF over and above those of socioeconomic status, standardized achievement, and high school GPA in predicting college outcomes.  相似文献   
190.
This study investigated whether the perception of self as socially rejected might contribute to increased physical aggression among elementary-school children. It was hypothesized that physically aggressive children would become more physically aggressive over time if they perceived that they were rejected and tended to blame peers for social failure experiences. Third-grade boys and girls (n = 941) were assessed in the Fall and Spring of the school year. Peer-report data on physical aggression and social preference were collected, along with self-report data on perceived rejection and attributions for social failure experiences. Results for boys were consistent with hypotheses, whereas the results for girls revealed a different pattern of relations. These results constitute prospective evidence that children's self-perceptions of social rejection can uniquely influence externalizing behavior. Results are discussed in terms of mechanisms that might mediate the relation between perceived rejection and physical aggression.  相似文献   
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