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We studied the course of aggressive behavior in an epidemiologically defined sample of first graders with and without comorbid anxious symptoms. Our primary purpose in doing so was to understand whether the stability of aggression in young children was attenuated or strengthened in the presence of comorbid anxiety. Previous studies of older children and adolescents had produced equivocal findings in this regard. Data on anxious symptoms were obtained through an interview of the children, whereas aggressive behavior was assessed through the use of a teacher interview and peer nominations. Assessments were performed in the fall and spring of first grade. In contrast to children classified as aggressive alone in the fall of first grade, boys and girls classified as aggressive and anxious in the fall of first grade were significantly more likely to be classified as aggressive in the spring in terms of teacher ratings and/or peer nominations of aggression. Thus our findings suggest that the link between early and later aggression may be strengthened in the presence of comorbid anxious symptoms, rather than attenuated. Future studies are needed to identify the mechanisms by which the course of aggression is influenced by the presence of comorbid anxiety.The writing of this paper was supported by the following National Institute of Mental Health grants: Epidemiologic Prevention Center for Early Risk Behavior (P50 MH38725); Periodic Outcome of Two Preventive Trials (1RO1 MH42968). The authors would like to thank the Baltimore Public City School System and the children and parents who participated in this study.  相似文献   
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Considerable scientific evidence demonstrates the reduction in risk for neural tube defects (NTDs) associated with maternal preconceptional folic acid supplementation. The National Society of Genetic Counselors (NSGC) endorses the U.S. Public Health Service recommendations for folic acid supplementation at the 0.4 mg level for women in the general population and at the 4.0 mg level for women at high or increased risk for NTD pregnancies for at least 4 weeks prior to active pursuit of conception. We encourage targeted educational efforts and surveillance to assess results of this dietary supplementation. The NSGC further urges the Food and Drug Administration to fortify staple foodstuffs with folic acid for a population-based approach to minimize the number of NTD births.  相似文献   
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Previous experiments have shown that overshoot rate in a linear positioning task is determined by the distance of the target from the boundary of the task in the direction of movement. Present experiments have served to specify distance more precisely as being relative rather than absolute, and as proximal rather than distal, and to show that the position of the boundary depends on the movements demanded by the task and not the visual and proprioceptive limits of the display. The operational boundary may be regarded as a cognitive construct by reference to which subjects locate targets.  相似文献   
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The purpose of the present research was to assess the relative influence of instigation or inhibition in mediating retaliation after arbitrary or non-arbitrary frustration. Sixty-four men were asked to learn a concept that was being taught by a peer. Although all men were frustrated, half were deliberately frustrated while the other half were not deliberately frustrated by the teacher. Following the task, the learner was given the opportunity to prevent the teacher from gaining employment under conditions where his evaluation was either anonymous or to be made public. The results of a 2 × 2 analysis of variance yielded several significant effects. The data revealed that subjects rejected the teacher more when the frustration was arbitrary than when it was non-arbitrary. Moreover, when the evaluation was anonymous, subjects rejected the teacher more than when the evaluation was to be made public. Furthermore, the difference in the amount of rejection expressed between arbitrary and non-arbitrary conditions was greater when the evaluation was anonymous than when it was public. These results were interpreted as demonstrating the greater contribution of instigatory rather than inhibitory factors in expressing aggression following deliberate or non-deliberate frustration.  相似文献   
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The short form of the Coopersmith Self-Esteem Inventory was administered to 952 fourth- and fifth-grade children (482 males, 470 females) from 41 classes. The children's teachers completed Coopersmith's Behavior Rating Form, a measure of self-esteem-related behavior. In the self-ratings, girls were significantly lower than boys; in the teachers' ratings, girls were significantly higher. In 32 of the 41 classes, boys ranked higher in their self-ratings than in the teacher ratings; the reverse was true for girls — a highly significant difference. This pattern of findings did not occur in the 8 classes which had male teachers. Issues concerning the measurement and conceptualization of self-esteem are discussed.This research was supported by Lehigh University, using Institutional Grant funds from the National Science Foundation. The authors wish to express their appreciation to Patricia Horton for her assistance in the collection of the data.  相似文献   
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