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151.
This longitudinal study of the effects of iron deficiency in infancy assessed motor development over time in 185 healthy Costa Rican children who varied in iron status at 12-23 months. Longitudinal analyses (hierarchical linear modeling) used the Bayley Psychomotor Index before and both 1 week and 3 months after iron treatment in infancy and the Bruninks-Oseretsky Test of Motor Proficiency - long form at 5 years and short form at 11-14 years. Children with chronic severe iron deficiency in infancy had lower motor scores at the beginning of the study and a lower but parallel trajectory for motor scores through early adolescence. Thus, there was no evidence of catch-up in motor development, despite iron therapy in infancy that corrected iron deficiency anemia in all cases.  相似文献   
152.
Cognitive models have guided effective intervention strategies in the treatment of depression. However, little is known about the cognitive model's relevance in different cultural ethnic groups in the United States. This study examines the cross-sectional and longitudinal associations among cognitive variables and depressive symptoms among African American, Caucasian, and Hispanic adolescents in the United States. Community adolescents (N = 450) ages 14-18 years (African American n = 79; Caucasian n = 273; Hispanic n = 98) provided information regarding their depressive symptoms and cognitions at two surveys, 6 months apart. Self-efficacy, cognitive errors, and hopelessness were associated with concurrent depressive symptoms at baseline. In addition, cognitive errors at baseline, controlling for baseline depressive symptoms and the occurrence of stressful events, predicted depressive symptoms at follow-up. Ethnic differences disappeared when parent education level was controlled. Our findings demonstrate support for the cognitive model of depression across ethnic groups. The importance of controlling for social class when examining ethnic differences in psychological variables is highlighted by our findings.  相似文献   
153.
Kinematic (relative phase error), metabolic (oxygen consumption, heart rate) and attentional (baseline and cycling reaction times) variables were measured while participants practised a high energy-demanding, intrinsically unstable 90 degrees relative phase coordination pattern on independent bicycle ergometers. The variables were found to be strongly inter-correlated, suggesting a link between emerging performance stability with practice and minimal metabolic and attentional cost. The effects of practice of 90 degrees relative phase coordination on the performance of in-phase (0 degrees-phase) and antiphase (180 degrees-phase) coordination were investigated by measuring the relative phase attractor layouts and recording the metabolic and attentional cost of the three coordination patterns before and after practice. The attentional variables did not differ significantly between coordination patterns and did not change with practice. Before practice, the coordination performance was most accurate and stable for in-phase cycling, with antiphase next and 90 degrees-phase the poorest. However, metabolic cost was lower for antiphase than either in-phase or 90 degrees-phase cycling, and the pre-practice attractor layout deviated from that predicted on the basis of dynamic stability as an attractor state, revealing an attraction to antiphase cycling. After practice of 90 degrees-phase cycling, in-phase cycling remained the most accurate and stable, with 90 degrees-phase next and antiphase the poorest, but antiphase retained the lowest metabolic energy cost. The attractor layout had changed, with new attractors formed at the practised 90 degrees-phase pattern and its symmetrical partner of 270 degrees-phase. Considering both the pre- and post-practice results, attractors were formed at either a low metabolic energy cost but less stable (antiphase) pattern or at a more stable but higher metabolic energy cost (90 degrees-phase) pattern, but in neither case at the most stable and accurate (in-phase) pattern. The results suggest that energetic factors affect coordination dynamics and that coordination modes lower in metabolic energy expenditure may compete with dynamically stable modes.  相似文献   
154.
One defining characteristic of skilled motor performance is the ability to complete the task with minimum energy expenditure. This experiment was designed to examine practice effects on coordination and control, metabolic energy expenditure, and muscle activation. Participants rowed an ergometer at 100 W for ten 16-min sessions. Oxygen consumption and perceived exertion (central and peripheral) declined significantly with practice and movement economy improved (reliably) by 9%. There was an associated but non-significant reduction in heart rate. Stroke rate decreased significantly. Peak forces applied to the ergometer handle were significantly less variable following practice and increased stability of the post-practice movement pattern was also revealed in more tightly clustered plots of hip velocity against horizontal displacement. Over practice trials muscle activation decreased, as revealed in integrated EMG data from the vastus lateralis and biceps brachii, and coherence analysis revealed the muscle activation patterns became more tightly coordinated. The results showed that practice reduced the metabolic energy cost of performance and practice-related refinements to coordination and control were also associated with significant reductions in muscle activation.  相似文献   
155.
Examined hypothesized gender and comorbidity differences in the observed classroom behavior of children with attention deficit hyperactivity disorder (ADHD). The behavior of 403 boys and 99 girls with ADHD, ages 7–10, was compared (a) to observed, sex-specific classroom behavior norms, (b) by sex, and (c) by comorbid subgroups. Boys and girls with ADHD deviated significantly from classroom norms on 15/16 and 13/16 categories, respectively. Compared to comparison girls, girls with ADHD had relatively high rates of verbal aggression to children. Boys with ADHD engaged in more rule-breaking and externalizing behaviors than did girls with ADHD, but the sexes did not differ on more neutral, unobtrusive behaviors. The sex differences are consistent with notions of why girls with ADHD are identified and referred later than boys. Contrary to hypothesis, the presence of comorbid anxiety disorder (ANX) was not associated with behavioral suppression; yet, as hypothesized, children with a comorbid disruptive behavior disorder (DBD) had higher rates of rule-breaking, and impulsive and aggressive behavior, than did children with ADHD alone and those with ADHD+ANX. Elevated rates of ADHD behaviors were also observed in children with comorbid DBD, indicating that these behaviors are truly present and suggesting that reports of higher ADHD ratings in this subgroup are not simply a consequence of negative halo effects and rater biases.  相似文献   
156.
Using a subsample of 105 children and their parents (100 mothers, 57 fathers) from the Multimodal Treatment Study of Children with ADHD (the MTA), the value of parents' baseline cognitions as predictors of children's treatment outcome at 14 months was examined. Measures of parents' cognitions about themselves, their ADHD children, and their parenting, as well as a self-report measure of dysfunctional discipline were included. Both mothers' and fathers' self-reported use of dysfunctional discipline predicted worse child treatment outcome. Low self-esteem in mothers, low parenting efficacy in fathers, and fathers' attributions of noncompliance to their ADHD child's insufficient effort and bad mood also were associated with worse child treatment outcome. All of these predictive relations were obtained even after MTA treatment effects had been taken into account. Secondary analyses indicated that mothers had a more external locus of control, lower self-esteem, lower parenting efficacy, and a greater tendency to attribute noncompliance to their ADHD child's bad mood than did fathers.  相似文献   
157.
The purpose of this study was to explore the relations between child responses to interparental depressive behavior and subsequent child depressive symptomatology. Data were collected on 156 two-parent families. Families completed questionnaire data and participated in problem-solving interactions, which were coded using a microsocial observational system. Three potential child responses to interparental depressive behavior were examined: facilitative, aggressive, and depressive. Results indicated that for female adolescents the displays of facilitative and depressive behavior as well as the suppression of aggressive behavior in response to interparental depressive behavior were related to increases in depressive symptomatology. For males, on the other hand, the display of aggressive and depressive behavior in response to interparental depressive behavior was related to increases in depression. Results provide preliminary support both for the examination of child responses to conflictual marital behavior and for expanding the conceptualization of conflictual marital behaviors to include depressive as well as the more traditionally examined aggressive behaviors, in order to better understand the link between conflictual marital behavior and child depressive symptomatology.  相似文献   
158.
The idea that a world in which everyone was born “perfect” would be a world in which something valuable was missing often comes up in debates about the ethics of technologies of prenatal testing and preimplantation genetic diagnosis (PGD). This thought plays an important role in the “disability critique” of prenatal testing. However, the idea that human genetic variation is an important good with significant benefits for society at large is also embraced by a wide range of figures writing in the bioethics literature, including some who are notoriously hostile to the idea that we should not select against disability. By developing a number of thought experiments wherein we are to contemplate increasing genetic diversity from a lower baseline in order to secure this value, I argue that this powerful intuition is more problematic than is generally recognized, especially where the price of diversity is the well-being of particular individuals.  相似文献   
159.
There is increasing interest in group therapy for the treatment of eating disorders. However, there is a lack of research evaluating group therapy that reflects on patient feedback in order to inform practice and improve treatment. This exploratory qualitative study attempted to evaluate patient feedback about the group therapy offered on a specialist inpatient eating disorders program. This qualitative analysis of patients’ feedback highlights areas for improvement that can be targeted to increase the effectiveness of the psychotherapy groups in the future. The research has implications for making inpatient hospitalization more effectively tailored to patients’ needs. This study also helps to improve qualitative research protocols.  相似文献   
160.
As part of an investigation into the effects of curricular reforms in the undergraduate program in the College of Engineering, a series of Perry-style interviews were conducted over a 4-year period. The study was undertaken in an attempt to assess the impact of collaborative design-based engineering courses that were being implemented. Students who completed the collaborative design course in their first year were higher on the Perry scale than their peers who did not. However, this effect was not sustained through the rest of the curriculum, as more traditional courses dominated. No statistically significant change in Perry position was observed for students in their 1st and 3rd years; however, a growth of approximately one Perry position was observed between the 3rd and 4th years. The relationship of current curricula to this pattern of intellectual development is discussed, and arguments for altering the curriculum to support intellectual development are made.  相似文献   
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