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201.
Listeners had the task of following a target speech signal heard against two competitors either located at the same spatial position as the target or displaced symmetrically to locations flanking it. When speech was the competitor, there was a significantly higher separation effect (maintained intelligibility with reduced target sound level), as compared with either steady-state or fluctuating noises. Increasing the extent of spatial separation slightly increased the effect, and a substantial contribution of interaural time differences was observed. When same- and opposite-sex voices were used, a hypothesis that the similarity between target and competing speech would explain the role for spatial separation was partly supported. High- and low-pass filtering showed that both parts of an acoustically similar competing signal contribute to the phenomenon. We conclude that, in parsing the auditory array, attention to spatial cues is heightened when the components of the array are confusable on other acoustic grounds.  相似文献   
202.
Examined patterns of friendship participation, stability, and quality among previously unfamiliar, ethnically diverse girls with attention-deficit/hyperactivity disorder (ADHD; n = 140) and comparison (n = 88) girls, aged 6–12 years, who attended 5-week naturalistic summer camps. Each girl completed sociometric nominations during Weeks 1, 3, and 5 of the camps; friendships were indexed by examining patterns of reciprocal nominations. At each assessment point, girls with ADHD had fewer mutual friends and were more likely to have no friends. Girls with Combined-type ADHD exhibited difficulties maintaining friendships from the beginning to middle of camp, whereas girls with Inattentive-type ADHD demonstrated poor friendship stability from the middle to end of camp. In general, girls with ADHD had higher levels of negative relationship features—including conflict and relational aggression—than did comparison girls, but levels of positive relationship features did not differ across subgroups. Friendship status predicted positive and negative peer regard, controlling for Verbal IQ and diagnostic status. Overall, although girls with ADHD were able to make friends to some extent, they differed from comparison girls in terms of the likelihood of doing so, the ability to maintain the friendships that they did form, and the levels of negative features found in their friendships.  相似文献   
203.
This study investigated mother-infant interactions in lowland gorillas (Gorilla gorilla gorilla) with particular focus on the relative role of mothers and infants in creating situations that are potentially conducive to infant social learning. Eleven gorilla mother-infant dyads were focally observed in weekly 1-hr sessions for 12 months. Spatial relationships were affected by age as well as by ambient temperature. Although the youngest infant was encouraged by its mother to walk and climb, mothers showed little or no encouragement in other contexts. In contrast, infants were quite interested in their mothers' activities, on some occasions repeated their mother's behavior, and actively encouraged their mothers to share food, play, or follow them. These findings suggest that gorilla infants are more active than their mothers in creating situations that are potentially conducive to the acquisition of knowledge or skills.  相似文献   
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205.
The authors attempted to use scores on the Video Suggestibility Scale for Children (VSSC, M. H. Scullin & S. J. Ceci, 2001) to predict 50 preschool children's performance during a field study in which they were interviewed suggestively 4 times about both a true event and a suggested event. Among the 25 children over age 4 years 6 months, tendencies on the VSSC to respond affirmatively to suggestive questions ("yield"), change answers in response to negative feedback ("shift"), and the sum of these ("total suggestibility") were all related to lack of accuracy about the true event in the field study and to both accuracy and lack of accuracy about the suggested event. Results support a 2-factor model of suggestibility.  相似文献   
206.
The Collaborative Multimodal Treatment Study of Children with Attention Deficit Hyperactivity Disorder (ADHD), the MTA, is the first multisite, cooperative agreement treatment study of children, and the largest psychiatric/psychological treatment trial ever conducted by the National Institute of Mental Health. It examines the effectiveness of Medication vs. Psychosocial treatment vs. their combination for treatment of ADHD and compares these experimental arms to each other and to routine community care. In a parallel group design, 579 (male and female) ADHD children, aged 7–9 years, 11 months, were randomly assigned to one of the four experimental arms, and then received 14 months of prescribed treatment (or community care) with periodic reassessments. After delineating the theoretical and empirical rationales for Psychosocial treatment of ADHD, we describe the MTA's Psychosocial Treatment strategy applied to all children in two of the four experimental arms (Psychosocial treatment alone; Combined treatment). Psychosocial treatment consisted of three major components: a Parent Training component, a two-part School Intervention component, and a child treatment component anchored in an intensive Summer Treatment Program. Components were selected based on evidence of treatment efficacy and because they address comprehensive symptom targets, settings, comorbidities, and functional domains. We delineate key conceptual and logistical issues faced by clinical researchers in design and implementation of Psychosocial research with examples of how these issues were addressed in the MTA study.Deceased  相似文献   
207.
To elucidate processes underlying therapeutic change in a large-scale randomized clinical trial, we examined whether alterations in self-reported parenting practices were associated with the effects of behavioral, medication, or combination treatments on teacher-reported outcomes (disruptive behavior, social skills, internalizing symptoms) in children with attention-deficit hyperactivity disorder (ADHD). Participants were 579 children with Combined-type ADHD, aged 7–9.9 years, in the Multimodal Treatment Study of Children with ADHD (MTA). We uncovered 2 second-order factors of parenting practices, entitled Positive Involvement and Negative/Ineffective Discipline. Although Positive Involvement was not associated with amelioration of the school-based outcome measures, reductions in Negative/Ineffective Discipline mediated improvement in children's social skills at school. For families showing the greatest reductions in Negative/Ineffective Discipline, effects of combined medication plus behavioral treatment were pronounced in relation to regular community care. Furthermore, only in combination treatment (and not in behavioral treatment alone) was decreased Negative/Ineffective Discipline associated with reduction in children's disruptive behavior at school. Here, children in families receiving combination treatment who showed the greatest reductions in Negative/Ineffective Discipline had teacher-reported disruptive behavior that was essentially normalized. Overall, the success of combination treatment for important school-related outcomes appears related to reductions in negative and ineffective parenting practices at home; we discuss problems in interpreting the temporal sequencing of such process-outcome linkages and the means by which multimodal treatment may be mediated by psychosocial processes related to parenting.  相似文献   
208.
Parenting and family stress treatment outcomes in the MTA study were examined. Male and female (579), 7–9-year-old children with combined type Attention Deficit Hyperactivity Disorder (ADHD), were recruited at six sites around the United States and Canada, and randomly assigned to one of four groups: intensive, multi-faceted behavior therapy program alone (Beh); carefully titrated and monitored medication management strategy alone (MedMgt); a well-integrated combination of the two (Comb); or a community comparison group (CC). Treatment occurred over 14 months, and assessments were taken at baseline, 3, 9, and 14 months. Parenting behavior and family stress were assessed using parent-report and child-report inventories. Results showed that Beh alone, MedMgt alone, and Comb produced significantly greater decreases in a parent-rated measure of negative parenting, Negative/Ineffective Discipline, than did standard community treatment. The three MTA treatments did not differ significantly from each other on this domain. No differences were noted among the four groups on positive parenting or on family stress variables. Results are discussed in terms of the theoretical and empirically documented importance of negative parenting in the symptoms, comorbidities and long-term outcomes of ADHD.  相似文献   
209.
Differences in perceptions of comfort, exertion, balance, and heart rate were investigated with two types of backpack. Subjects were 20 male volunteers (M age = 24.3 yr., SD: 3.6, M height = 180.02 cm, SD: 8.0, and M weight = 86.46 kg, SD: 14.84). Following oral briefing and practice trials, each subject was fitted at random with either an internal- or external-frame backpack containing 18.2 kg. By random, cross-over design, subjects completed a 30-m simulated hiking trial consisting of 16 separate obstacles designed to resemble actual off-trail hiking. Trials were conducted in a controlled environment with the walking intensity regulated by a metronome. Upon completion of each trial, the subjects rated the experience on perceived comfort, balance and stability, and rating of perceived exertion. Heart rate was recorded immediately prior to and following each trial. Analysis yielded a significant difference only on rating of perceived exertion in favor of the internal-frame backpack. Under limited circumstances, these data suggest that both types of backpacks provide similar comfort and balance and stability; however, internal frames in backpacks may reduce perceived exertion during short, demanding hikes.  相似文献   
210.
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