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791.
Many family therapies for adolescent drug use include ecological interventions. The purpose of this randomized clinical trial was to establish whether ecological interventions contribute to the impact of family therapy above and beyond the contributions of family process-only interventions. A family-based ecological approach, structural ecosystems therapy (SET), was compared with family process-only condition (FAM) and community services control (CS). One hundred ninety substance-abusing or dependent African American and Hispanic adolescents were randomized to SET, FAM, or CS. Follow-up assessments were conducted at 3, 6, 12, and 18 months postrandomization. SET was significantly more efficacious than FAM and CS in reducing adolescent drug use. However, these improvements were limited to Hispanic adolescents. The study demonstrates the importance of investigating changes in adolescent drug use as a result of treatment condition across more than 1 racial/ethnic group.  相似文献   
792.
This study examines international adoptees and factors associated with searching for birth parents. A total of 1,417 international adoptees in The Netherlands, aged 24 to 30 years, were divided into 4 groups: uninterested nonsearchers, interested nonsearchers, searchers, and reunited searchers. In total, 32% of adoptees had searched. Although the majority of searchers were well-adjusted, they had more problems--mainly internalizing problems--than uninterested nonsearchers. These problems, however, were not caused by the search itself. It is concluded that searching is the product of natural curiosity influenced by external factors such as the divorce of adoptive parents and the options for searching.  相似文献   
793.
I argue that standard decision theories, namely causal decision theory and evidential decision theory, both are unsatisfactory. I devise a new decision theory, from which, under certain conditions, standard game theory can be derived.
Frank ArntzeniusEmail:
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794.
We have developed a process model that learns in multiple ways while finding faults in a simple control panel device. The model predicts human participants' learning through its own learning. The model's performance was systematically compared to human learning data, including the time course and specific sequence of learned behaviors. These comparisons show that the model accounts very well for measures such as problem-solving strategy, the relative difficulty of faults, and average fault-finding time. More important, because the model learns and transfers its learning across problems, it also accounts for the faster problem-solving times due to learning when examined across participants, across faults, and across the series of 20 trials on an individual participant basis. The model shows how learning while problem solving can lead to more recognition-based performance, and helps explain how the shape of the learning curve can arise through learning and be modified by differential transfer. Overall, the quality of the correspondence appears to have arisen from procedural, declarative, and episodic learning all taking place within individual problem-solving episodes.  相似文献   
795.
796.
The study reported here compares two linguistically informed hypotheses on agrammatic sentence production, the TPH [Friedmann, N., & Grodzinsky, Y. (1997). Tense and agreement in agrammatic production: Pruning the syntactic tree. Brain and Language, 56, 397-425.] and the DOP [Bastiaanse, R., & van Zonneveld, R. (2005). Sentence production with verbs of alternating transitivity in agrammatic Broca's aphasia. Journal of Neurolinguistics, 18, 59-66]. To explain impaired production of non-canonical sentences in agrammatism, the TPH basically relies on deleted or pruned clause structure positions in the left periphery, whereas the DOP appeals to limitations in the application of movement rules. Certain non-canonical sentences such as object-questions and object-relative clauses require the availability of nodes in the left periphery as well as movement to these nodes. In languages with relatively fixed word order such as English, the relevant test cases generally involve a coincidence of left periphery and movement, such that the predictions of the TPH and the DOP are identical although for different reasons. In languages with relatively free word order such as German, on the other hand, it is possible to devise specific tests of the different predictions due to the availability of scrambling. Scrambled object sentences, for example, do not involve the left periphery but do require application of movement in a domain below the left periphery. A study was conducted with German agrammatic subjects which elicited canonical sentences without object movement and non-canonical scrambled sentences with object movement. The results show that agrammatic speakers have a particular problem with the production of scrambled sentences. Further evidence reported in the study from spontaneous speech, elicitation of object relatives, questions and passives and with different agrammatic subjects confirms that non-canonical sentences are generally harder to produce for agrammatics. These findings provide evidence in favor of the DOP and it will be argued that a cross-modal explanation of agrammatic deficits is possible if two factors--movement and canonicity--are taken into consideration.  相似文献   
797.
Simmons C  Worrell FC  Berry JM 《Assessment》2008,15(3):259-276
In this study, we examined the internal consistency and the structural validity of scores on the African Self-Consciousness Scale (ASCS), the Multidimensional Inventory of Black Identity (MIBI), and the Cross Racial Identity Scale (CRIS). Participants consisted of 225 African American college students--75 attending predominantly White institutions (PWIs) and 150 attending historically Black colleges and universities (HBCUs). Internal consistency estimates were above .60 for scores on one ASCS subscale, six MIBI subscales, and six CRIS subscales. Exploratory factor analytic procedures supported a two-factor structure for ASCS scores, a five-factor structure for MIBI scores, and a six-factor structure for CRIS scores. Implications for Black racial identity and scale development are discussed.  相似文献   
798.
799.
A pivotal period in the development of language occurs in the second year of life, when language comprehension undergoes rapid acceleration. However, the brain bases of these advances remain speculative as there is currently no functional magnetic resonance imaging (fMRI) data from healthy, typically developing toddlers at this age. We investigated the neural basis of speech comprehension in this critical age period by measuring fMRI activity during passive speech comprehension in 10 toddlers (mean +/- SD; 21 +/- 4 mo) and 10 3-year-old children (39 +/- 3 mo) during natural sleep. During sleep, the children were presented passages of forward and backward speech in 20-second blocks separated by 20-second periods of no sound presentation. Toddlers produced significantly greater activation in frontal, occipital, and cerebellar regions than 3-year-old children in response to forward speech. Our results suggest that rapid language acquisition during the second year of life may require the utilization of frontal, cerebellar, and occipital regions in addition to classical superior temporal language areas. These findings are consistent with the interactive specialization hypothesis, which proposes that cognitive abilities develop from the interaction of brain regions that include and extend beyond those used in the adult brain.  相似文献   
800.
This study examined the separate and combined effects of stimulus valence and arousal on retrieval inhibition. Participants performed Anderson and Green's (2001) memory suppression task with stimuli varying across dimensions of valence and arousal. Memory was tested through free and cued recall as well as speeded recognition. Results showed that both stimulus valence and arousal influenced the extent to which participants successfully inhibited retrieval, but not in the ways anticipated. Specifically, the strongest inhibition effects were for highly arousing, pleasant words. In addition, unpleasant stimuli that were suppressed were better recalled during both cued and free-recall tasks than pleasant stimuli that were suppressed. Across all tests of memory performance, there were no significant differences between the experimental conditions for highly arousing, unpleasant words. The implications of these findings are discussed.  相似文献   
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