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Preschool‐aged children (n = 274) were examined in the laboratory to assess behavioral and cortisol responses to nonsocial and social threat. Parents also responded to scales on the Children's Behavior Questionnaire reflecting exuberant approach to novel/risky activities (reversed scored) and shyness. Multi‐method measures of Nonsocial and Social Inhibition were computed. Parents and children were observed engaging in a series of interactive tasks and the Emotional Availability scales were scored for parental sensitivity, nonintrusiveness, nonhostility, and structuring. These scores were factored to yield one measure of Parenting Quality. Analyses revealed that Nonsocial and Social Inhibition could be distinguished and that associations with cortisol response were stressor specific. Moderation analyses revealed that parenting quality buffered cortisol elevations for extremely socially, but not nonsocially inhibited children. These findings are consistent with evidence that sensitive, supportive parenting is an important buffer of the HPA axis response to threat in infants and toddlers, and extends this finding to the preschool period. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 521–532, 2009.  相似文献   
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We assessed the effects of varying the treatment integrity of a prompting procedure on appropriate toy manipulation in two preschool-aged children with autism. Following an assessment to identify toys with high levels of inappropriate toy manipulation, each of three toys was associated with implementation of the prompting procedure at a different integrity level (10%, 50%, or 100%). For one participant, only the 100% integrity condition produced increases in appropriate toy manipulation. For the second participant, both the 50% and 100% integrity conditions produced increases in appropriate toy manipulation. These results suggest that integrity errors negatively impacted the acquisition of appropriate toy manipulation in children with autism, although the necessary level of treatment integrity varied across participants.  相似文献   
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Recovery heart rate (RHR) has been used in adults to evaluate cardiovascular (CV) fitness, but less is known about RHR in children. Data from 1,276 participants in Project Healthy Schools, a school-based intervention in southeast Michigan, were collected. In addition, to demographic characteristics, physiologic factors examined included body mass index (BMI), lipid and glucose levels, blood pressure, and HR. Information on diet, physical activity, and sedentary behavior was collected through self-report. RHR was determined by measurement of HR after a 3-minute step test. Using quartiles of RHR as a marker of fitness, associations with demographic, physiologic, and behavioral factors were explored using χ2 and Student t tests. Compared with children in the lowest quartile of RHR (i.e., most fit), those in the upper quartile of RHR (i.e., least fit) had greater mean LDL cholesterol (93.0 vs. 86.7 mg/dL; P = 0.02) and lower mean HDL cholesterol (50.9 vs. 55.9 mg/dL; P < 0.001). Children in the upper 95 % of BMI had greater mean RHR compared with those in the normal BMI range (116.6 vs. 100.3 kg/m2). Children in the upper quartile of RHR reported fewer days of vigorous to moderate exercise per week compared with children in the lowest quartile of RHR [4.8 vs. 4.1 (P < 0.001) for moderate exercise and 3.6 vs. 3.0 (P = 0.001) for vigorous exercise]. Among middle school children, RHR appears to be associated with physiologic parameters and health behaviors. RHR may be useful for identifying children at increased risk for developing CV risk factors.  相似文献   
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Lysophosphatidic acid (LPA) is a signaling lipid that binds to six known lysophosphatidic acid receptors (LPARs), named LPA1-LPA6. These receptors initiate signaling cascades relevant to development, maintenance, and healing processes throughout the body. The diversity and specificity of LPA signaling, especially in relation to cancer and autoimmune disorders, makes LPA receptor modulation an attractive target for drug development. Several LPAR-specific analogues and small molecules have been synthesized and are efficacious in attenuating pathology in disease models. To date, at least three compounds have passed phase I and phase II clinical trials for idiopathic pulmonary fibrosis and systemic sclerosis. This review focuses on the promising therapeutic directions emerging in LPA signaling toward ameliorating several diseases, including cancer, fibrosis, arthritis, hydrocephalus, and traumatic injury.  相似文献   
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