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191.
192.
This study examines the quality of the transition into employment roles among a socioeconomically diverse cohort of 1,143 high school seniors who were interviewed as seniors in 1998 and 2 years later. Focusing on both subjective and objective dimensions of work adaptation, analyses examine differences in these outcomes associated with taking a high school career-major versus a more traditional academic program. This type of major is intended to assist in the career development and economic adaptation of more disadvantaged young adults and follows from an ecological model emphasizing the importance of connections between educational and employment institutions in the socialization of young people. Results indicate small but significant effects of having the career-major for the perceptual variables. Group differences were not found for the variables assessing more objective qualities of their jobs. The discrepancy between subjective and objective outcomes may suggest a short-term psychological optimism in the absence of an objective situation that would justify this view. Discussion centers on the need for stronger institutional support for school-work connections.  相似文献   
193.
Children with attention deficit hyperactivity disorder (ADHD) face an increased risk of poor achievement in school. Thus, knowledge of the cognitive processing abilities of children with ADHD is critical to understanding and improving their academic performance. Although many studies have focused on the specific nature of the attention deficit experienced by children with ADHD, few have examined higher order cognitive processing such as comprehension of stories. The present study examined the processes of encoding story information, building a story representation, and modifying a story representation in boys with ADHD and nonreferred boys. Boys were asked to narrate a story from a picture book twice. Boys with ADHD showed deficits in representing goals and goal plans in their narrations, as compared to nonreferred boys. Boys with ADHD also committed more errors than nonreferred boys, but did correct certain types of errors on their second telling. Implications are discussed in terms of future research needed to identify the cognitive deficits that account for these narrative deficits.  相似文献   
194.
A 14-min continuous performance test (CPT) requiring a high rate of responding was administered to a probability-weighted random sample of 816 9–17-year-old children drawn from a population of 17,117 children in an ongoing epidemiological and longitudinal study in Western North Carolina. Systematic main effects of improved performance with older age were found in this age range for all variables, including reaction time (RT), RT standard error, errors of omission, errors of commission, and signal detection parameters (d' and ). Significant gender main effects included more impulsive errors, less variability, and faster RT by males, with no interactions between age and gender. There were no main effects of ethnicity or interactions of ethnicity with age and/or gender. Large main effects of interstimulus interval (ISI; 1, 2, or 4-s intervals) and time block were present for most CPT performance measures. The normative data from the CPT should provide a useful framework for interpreting similar data in future studies of child and adolescent psychopathology.  相似文献   
195.
People often place undue weight on specific sources of information (case cues) and insufficient weight on more global sources (base rates) even when the latter are highly predictive, a phenomenon termed base-rate neglect. This phenomenon was first demonstrated with paper-and-pencil tasks, and also occurs in a matching-to-sample procedure in which subjects directly experience case sample (cue) accuracy and base rates, and in which discrete, nonverbal choices are made. In two nonverbal experiments, subjects were exposed to hundreds of trials in which they chose between two response options that were both probabilistically reinforced. In Experiment 1, following one of two possible samples (the unpredictive sample), either response was reinforced with a .5 probability. The other sample (predictive) provided reinforcement for matching on 80% of the trials in one condition but in only 20% of the trials in another condition. Subjects' choices following the unpredictive sample were determined primarily by the contingencies in effect for the predictive sample: If matching was reinforced following the predictive sample, subjects tended to match the unpredictive sample as well; if countermatching the predictive sample was generally reinforced, subjects tended to countermatch the unpredictive sample. These results demonstrate only weak control by base rates. In Experiment 2, base rates and sample accuracy were simultaneously varied in opposite directions to keep one set of conditional probabilities constant. Subjects' choices were determined primarily by the overall accuracy of the sample, again demonstrating only weak control by base rates. The same pattern of choice occurred whether this pattern increased or decreased rate of reinforcement. Together, the results of the two experiments provide a clear empirical demonstration of base-rate neglect.  相似文献   
196.
Heart Rate Variability and Sustained Attention in ADHD Children   总被引:4,自引:0,他引:4  
The major goal of the current study was to investigate the association between continuous performance tests (CPTs) and the heart rate variability (HRV) of attention deficit hyperactivity disorder (ADHD) children. The HRV, specifically the 0.10-Hz component, may be considered to be a psychophysiological index of effort allocation (motivation): The less effort the subject allocates, the greater the 0.10-Hz component. Results indicated that, compared to controls, ADHD subjects had a greater 0.10-Hz component, which was associated with poor test performance over time. Thus, using a psychophysiological measure, we were able to confirm the clinical concept of ADHD from a motivational perspective.  相似文献   
197.
We investigated exploratory eye movements to thematic pictures in schizophrenic, attention-deficit/hyperactivity disorder (ADHD), and normal children. For each picture, children were asked three questions varying in amount of structure. We tested if schizophrenic children would stare or scan extensively and if their scan patterns were differentially affected by the question. Time spent viewing relevant and irrelevant regions, fixation duration (an estimate of processing rate), and distance between fixations (an estimate of breadth of attention) were measured. ADHD children showed a trend toward shorter fixations than normals on the question requiring the most detailed analysis. Schizophrenic children looked at fewer relevant, but not more irrelevant, regions than normals. They showed a tendency to stare more when asked to decide what was happening but not when asked to attend to specific regions. Thus, lower levels of visual attention (e.g., basic control of eye movements) were intact in schizophrenic children. In contrast, they had difficulty with top-down control of selective attention in the service of self-guided behavior.  相似文献   
198.
Vigilance deficits have been found in both schizophrenic and ADHD subjects. The two patient groups have never been directly compared on any vigilance measure, however. In the present study 20 early-onset schizophrenics were compared to 20 ADHD adolescents on a Degraded Stimulus Continuous Performance Test (DS-CPT). A comparison group of 30 normal adolescents was also included. Results showed no significant differences between the three groups on any of the DS-CPT measures. Different hypotheses are put forth to explain the findings, among them that the task may be insensitive to identifying sustained attention deficits in adolescent populations.  相似文献   
199.
A wealth of research is available examining children's story comprehension. However, little attention has been directed toward understanding the story comprehension of children with attention deficit hyperactivity disorder (ADHD). The present paper attempts to integrate the developmental literature on children's story comprehension with the little that is known about the story comprehension processes of children with ADHD. This review is guided by a network model of story representation that emphasizes the structure of causal and enabling relations between story events. Examination of the available studies indicates that children with ADHD lag behind their peers in their understanding of causal relations, and that their attentional problems may contribute to difficulties in understanding factual information in the preschool years and causally related information in the elementary years. Some evidence also is presented suggesting that children with ADHD are less effective in taking advantage of story structure features in guiding their recall of story events. Suggestions for future research are offered that would elaborate our knowledge of the developmental progression in the processing of complex information by children with ADHD.  相似文献   
200.
Based on the delay-reduction hypothesis, a less profitable schedule should be rejected if its duration exceeds the mean delay to reinforcement. It should be accepted if its duration is shorter than the mean delay. This was tested for humans, using a successive-choice schedule. The accessibility of the less profitable (variable-interval 18 s) schedule was varied by changing the duration (in terms of a fixed interval) of the waiting-time component preceding its presentation. Forty-eight students were randomly assigned to three groups. In Phase 1, the duration of the less profitable schedule equaled the mean delay to reinforcement in all groups. In Phase 2, waiting time preceding the less profitable schedule was reduced in Group 1 and increased in Group 2. Thus, the schedule was correlated either with a relative delay increase (Group 1) or a delay reduction (Group 2). In Group 3, conditions remained unchanged. As predicted, acceptance of the less profitable schedule decreased in Group 1 and increased in Group 2. The increased acceptance in Group 2 was accompanied by a decreased acceptance of the more profitable (variable-interval 3 s) schedule, resembling a pattern of negative contrast. Response rates were higher under the component preceding (a) the more profitable schedule in Group 1 and (b) the less profitable schedule in Group 2. Implications for the modification of human choice behavior are discussed.  相似文献   
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