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861.
In this report, we examine whether and how altered aspects of perception and attention near the hands affect one’s learning of to-be-remembered visual material. We employed the contextual cuing paradigm of visual learning in two experiments. Participants searched for a target embedded within images of fractals and other complex geometrical patterns while either holding their hands near to or far from the stimuli. When visual features and structural patterns remained constant across to-be-learned images (Exp. 1), no difference emerged between hand postures in the observed rates of learning. However, when to-be-learned scenes maintained structural pattern information but changed in color (Exp. 2), participants exhibited substantially slower rates of learning when holding their hands near the material. This finding shows that learning near the hands is impaired in situations in which common information must be abstracted from visually unique images, suggesting a bias toward detail-oriented processing near the hands.  相似文献   
862.
Changes to our everyday activities mean that adult language users need to learn new meanings for previously unambiguous words. For example, we need to learn that a "tweet" is not only the sound a bird makes, but also a short message on a social networking site. In these experiments, adult participants learned new fictional meanings for words with a single dominant meaning (e.g., "ant") by reading paragraphs that described these novel meanings. Explicit recall of these meanings was significantly better when there was a strong semantic relationship between the novel meaning and the existing meaning. This relatedness effect emerged after relatively brief exposure to the meanings (Experiment 1), but it persisted when training was extended across 7?days (Experiment 2) and when semantically demanding tasks were used during this extended training (Experiment 3). A lexical decision task was used to assess the impact of learning on online recognition. In Experiment 3, participants responded more quickly to words whose new meaning was semantically related than to those with an unrelated meaning. This result is consistent with earlier studies showing an effect of meaning relatedness on lexical decision, and it indicates that these newly acquired meanings become integrated with participants' preexisting knowledge about the meanings of words.  相似文献   
863.
Externalizing psychopathology (EXT) is a framework for understanding diagnostic comorbidity and etiology of antisocial and substance-use behaviors. EXT indicates continuity in adulthood but the structure of adolescent EXT is less clear. This report examines whether adolescent EXT is trait-like, as has been found with adults, or categorical. We use tests of measurement invariance to determine how diagnostic indicators of EXT differ in adolescents compared to adults. The EXT measures employed were DSM-IIIR diagnoses of adult antisocial behavior, conduct disorder, and alcohol, marijuana, and drug dependence. Latent trait, latent class, and hybrid models were fit to two separate data sets: 2,769 seventeen-year-old adolescents and 2,619 adults from the Minnesota Twin Family Study. The best model in both samples was a single-trait LT model. Parameters from the adolescent and adult models were equivalent for all disorders except alcohol dependence. It appears that EXT in adolescence can be accurately represented by a single-trait model, and the measurement properties of EXT are similar during these time periods with the exception of alcohol dependence.  相似文献   
864.
Examined a cognitive-behavioral pathway by which depressive symptoms in mothers and fathers increase risk for later child externalizing problem behavior via parents’ appraisals of child behavior and physical discipline. Participants were 245 children (118 girls) at risk for school-age conduct problems, and their parents and teachers. Children were approximately 3 years old at Time 1 (T1) and 5 ½ years old at Time 2 (T2). At T1, mothers and fathers reported their depressive symptoms, perceptions of their child’s reciprocal affection and responsiveness, frequency of physical punishment, and child externalizing problems. Mothers, fathers, and teachers provided ratings of externalizing behavior at T2. Structural equation modeling revealed that parents’ negative attributions mediated positive relations between their depressive symptoms and frequency of physical punishment for both fathers and mothers. More frequent physical punishment, in turn, predicted increased child externalizing behavior at T2. In future research, transactional mechanisms underlying effects of clinical depression on child conduct problems should be explored at multiple stages of development. For parents showing depressive symptoms, restructuring distorted perceptions about their children’s behavior may be an important component of intervention programs.  相似文献   
865.
As research continues to document differences in the prevalence of mental health problems such as depression across racial/ethnic groups, the issue of measurement equivalence becomes increasingly important to address. The Mood and Feelings Questionnaire (MFQ) is a widely used screening tool for child and adolescent depression. This study applied a differential item functioning (DIF) framework to data from a sample of 6th and 8th grade students in the Seattle Public School District (N = 3,593) to investigate the measurement equivalence of the MFQ. Several items in the MFQ were found to have DIF, but this DIF was associated with negligible individual- or group-level impact. These results suggest that differences in MFQ scores across groups are unlikely to be caused by measurement non-equivalence.  相似文献   
866.
Competing hypotheses for explaining the role of anxiety in the relation between attention-deficit/hyperactivity disorder (ADHD) symptoms and childhood aggression were evaluated. Two studies tested whether anxiety exacerbated, attenuated, or had no effect on the relation between ADHD and aggression subtypes among psychiatrically hospitalized children. In Study 1 (N = 99), children who scored above clinical cut-off levels for anxiety only, ADHD only, and co-occurring ADHD and anxiety were compared on aggression subtypes (i.e., reactive, proactive, overt, and relational aggression). In Study 2, the moderating role of anxiety on the relation between ADHD and aggression subtypes was examined with a larger sample (N = 265) and with continuous variables. No support was found for either the attenuation or exacerbation hypothesis, and results remained consistent when separately examining hyperactivity/impulsivity and inattention symptoms of ADHD. Although ADHD symptoms were significantly associated with all aggression subtypes, this association did not remain when including symptoms of oppositional defiant disorder.  相似文献   
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870.
Research has documented that children and adolescents with attention-deficit/hyperactivity disorder (ADHD) are at increased risk of substance use problems. Few studies, however, have focused on early-onset substance use. This study therefore investigated how the two symptom dimensions of ADHD (hyperactivity/impulsivity and inattention) are associated with early-onset substance use, the role of persistent ADHD for the association, and to what extent the association is influenced by genetic and environmental factors. Twins (1,480 pairs) in the Swedish Twin Study of Child and Adolescent Development were followed from childhood to adolescence. ADHD symptoms were measured at age 8–9 and age 13–14 via parent-report, whereas substance use was assessed at age 13–14 via self-report. Results revealed that hyperactive/impulsive symptoms predicted early-onset “sometimes” tobacco use (adjusted odds ratios, 1.12, for one symptom count), controlling for inattentive symptoms and conduct problem behaviors. There is no independent effect of inattentive symptoms on early-onset substance use. Children with persistent hyperactivity/impulsivity (defined as scoring above the 75th percentile at both time points) had a pronounced risk of both early-onset tobacco and alcohol use (adjusted odds ratios from 1.86 to 3.35, compared to the reference group). The associations between hyperactivity/impulsivity and early-onset substance use were primarily influenced by genetic factors. Our results indicated that hyperactivity/impulsivity, but not inattention, is an important early predictor for early-onset substance use, and a shared genetic susceptibility is suggested to explain this association.  相似文献   
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