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971.
Background: Specialized 12-step based groups have emerged to address the needs of persons recovering from both substance abuse and psychiatric illness. Objective: This study investigates the role of social support in mediating the association between mutual aid participation and subsequent substance use for dually diagnosed persons. Method: A cohort of Double Trouble in Recovery (DTR) members in New York City were studied prospectively over a two-year period. Findings: Longer DTR participation during the first year of the study was associated with lower substance use in the second year; that effect was partially explained by the maintenance of high level of social support. Conclusion: These findings speak of the enduring influence of 12-step attendance on reducing substance use, and underline the importance of both 12-step attendance and supportive networks for dually diagnosed persons.  相似文献   
972.
Three experiments investigated the relationship between subjective experience and attentional lapses during sustained attention. These experiments employed two measures of subjective experience (thought probes and questionnaires) to examine how differences in awareness correspond to variations in both task performance (reaction time and errors) and psycho-physiological measures (heart rate and galvanic skin response). This series of experiments examine these phenomena during the Sustained Attention to Response Task (SART, Robertson, Manly, Adrade, Baddeley, & Yiend, 1997). The results suggest we can dissociate between two components of subjective experience during sustained attention: (A) task unrelated thought which corresponds to an absent minded disengagement from the task and (B) a pre-occupation with one's task performance that seems to be best conceptualised as a strategic attempt to deploy attentional resources in response to a perception of environmental demands which exceed ones ability to perform the task. The implications of these findings for our understanding of how awareness is maintained on task relevant material during periods of sustained attention are discussed.  相似文献   
973.
Subpart D of 45 CFR 46 focuses on research involving children. Section 46.407 addresses research that is not otherwise approvable. The research is not otherwise approvable because either (1) it seeks to enroll healthy children, but offers no prospect of direct benefit and entails more than minimal risk; or (2) it seeks to enroll children with a disorder or condition, but offers no prospect of direct benefit and entails more than a minor increase over minimal risk. According to 46.407, such research can be permissible if it is approved by a panel of experts. Prior to 2000, only two 407 panels had been convened, but in 2001, the Office for Human Research Protections received more than 20 protocols for 407 review. The first, entitled "Precursors to Diabetes in Japanese American Youth," serves here as a case study in human subject protections.  相似文献   
974.
The hippocampus and memory for "what," "where," and "when"   总被引:2,自引:0,他引:2       下载免费PDF全文
Previous studies have indicated that nonhuman animals might have a capacity for episodic-like recall reflected in memory for "what" events that happened "where" and "when". These studies did not identify the brain structures that are critical to this capacity. Here we trained rats to remember single training episodes, each composed of a series of odors presented in different places on an open field. Additional assessments examined the individual contributions of odor and spatial cues to judgments about the order of events. The results indicated that normal rats used a combination of spatial ("where") and olfactory ("what") cues to distinguish "when" events occurred. Rats with lesions of the hippocampus failed in using combinations of spatial and olfactory cues, even as evidence from probe tests and initial sampling behavior indicated spared capacities for perception of spatial and odor cues, as well as some form of memory for those individual cues. These findings indicate that rats integrate "what," "where," and "when" information in memory for single experiences, and that the hippocampus is critical to this capacity.  相似文献   
975.
Mounting evidence concerning obsessive-compulsive disorders points to abnormal functioning of the orbitofrontal cortices. First, patients with obsessive-compulsive disorder (OCD) perform poorly on tasks that rely on response suppression/motor inhibition functions mediated by the orbitofrontal cortex relative to both normal and clinical controls. Second, patients with OCD exhibit functional hyperactivity in lateral orbitofrontal and related structures corresponding with symptom severity. In this article, we compare these neurocognitive correlates of OCD with the executive and neural underpinnings of "compulsive-like" behaviors that are common in normal childhood. We discuss the phenomenology and natural history of normative compulsive-like behaviors as well as the behavioral, emotional, and cognitive continuities between typical and pathological obsessive-compulsive behaviors. We then examine associations between children's executive performance deficits and their observed compulsive-like characteristics. We relate these patterns to executive deficits shown by adults with OCD. Finally, we speculate on the developmental neurobiology of children's compulsive-like behaviors, with particular attention to orbitofrontal functions including behavioral and emotional regulation, and we suggest similarities and differences with the neurobiology of OCD. In making these comparisons, we hope to open a dialogue between researchers who study underlying brain pathologies associated with OCD and those who explore the neurocognitive bases of normal development.  相似文献   
976.
977.
The present study provides evidence that individuals who have different patterns of cerebral lateralization and who develop along different maturational time courses can attain comparable levels of language proficiency. Right-handed individuals with left-handed family members (left-handed familials, LHFs) showed a shorter sensitive period for language acquisition than did right-handed individuals with only right-handed family members (right-handed familials, RHFs). The shorter sensitive period for LHFs may be due to a focus on non-linguistic, word-based conceptual information during language acquisition. RHFs may focus on grammatical relations during language acquisition, which matures later than lexical knowledge. This suggests that there may be different patterns of cerebral lateralization for language in all normal populations as a function of familial handedness.  相似文献   
978.
979.
In the first study, a hierarchical structure of personality traits was identified using data from a longitudinal study tracing two samples of men from adolescence to midlife (i.e., a representative sample of the general population and a sample of individuals adjudicated during their adolescence). The second study examined structural, rank-order, and mean-level continuity. Partial structural continuity was demonstrated through confirmatory factor analysis. Regarding rank-order continuity, the correlations were stronger as age increased, particularly for the adjudicated men. For mean-level continuity, the adjudicated men displayed higher scores from adolescence to midlife for nearly every personality trait related to Disinhibition and Negative Emotionality. Significant decreases were observed in these traits for both samples, supporting the hypothesis of a normative psychological maturation. Although both samples showed this maturation, the adjudicated men displayed a lower rate of change during adolescence and early adulthood. The two samples did not differ in Extraversion and this trait remained more stable, particularly for adjudicated men.  相似文献   
980.
A dynamical model is used to show that global motion pattern formation for several different apparent motion stimuli can be embodied in the stable distribution of activation over a population of concurrently activated, directionally selective motion detectors. The model, which is based on motion detectors being interactive, noisy, and self-stabilizing, accounts for such phenomena as bistability, spontaneous switching, hysteresis, and selective adaptation. Simulations show that dynamical solutions to the motion correspondence problem for a bistable stimulus (two qualitatively different patterns are formed) apply as well to the solution for a monostable stimulus (only one pattern is formed) and highlight the role of interactions among sequentially stimulated detectors in establishing the state dependence and, thereby, the temporal persistence of percepts.  相似文献   
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