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ABSTRACT

Increased focus on sports-related concussion (SRC) in football in the media, and mandatory concussion education for parents of youth sport athletes, may result in parental concern that youth athletes will experience long-term effects from concussion. We sought to identify beliefs about long-term effects of concussion in parents of youth soccer athletes. Four hundred and eleven parents from soccer leagues in three states completed a survey assessing parents’ perceptions and knowledge of long-term effects of SRC. Nearly all youth soccer parents surveyed (96.5%) believe there are long-term effects from SRCs, 76% reported concern their child would sustain a concussion, and 71% had talked with their child about concussion symptoms/reporting. Parents ranked tackle football as having the highest risk for concussion, followed by soccer, ice hockey, cheerleading, and lacrosse. Parents of children that had previously sustained a concussion were 8.3x more likely to be concerned their child would sustain a concussion, and parents with a personal history of concussion were 2x more likely to consider not allowing their child to participate in youth sports. There are wide-spread beliefs among youth soccer parents regarding long-term effects of SRCs, and concerns their children will sustain concussions while participating in youth sports.  相似文献   
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Quantitative analysis can reveal the consistency of intervention effects across studies, as well as the variation of effects according to study-level characteristics. After consulting with project experts in methods and content, and reviewing the literatures on research synthesis and on HIV prevention, we developed a systematic protocol of analytical methods for synthesis of behavioral and biologic outcome data from HIV intervention studies. This protocol included procedures for identifying eligible studies; defining, characterizing, and prioritizing outcomes; abstracting and calculating estimates of effect; adjusting for baseline distributions and intraclass correlation; transforming estimates to a common metric; summarizing effects; examining differences in effectiveness among groups of studies; and translating these results into terms useful to HIV prevention practitioners and researchers. We applied these procedures to transform outcome data reported in many different statistical formats into odds ratios that could be combined and compared across studies. We analyzed data on behaviors related to sexual risk for HIV infection (unprotected sex, condom use, and number of partners) as well as data on biologic outcomes (incidence of HIV and other sexually transmitted infections). This framework may be useful for meta-analyses of prevention research in other fields, particularly when primary research features diverse outcome measures and methods of analysis.  相似文献   
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BACKGROUND: Dissociation, defined as a disruption in usually integrated mental functions, is found not only in DSM-IV dissociative disorders, but also in post-traumatic stress disorder and eating disorders. Dissociative phenomena are also common in the general population, and may reflect a constitutionally determined cognitive style rather than a pathological trait acquired through experiencing adverse life events. In pathological dissociation, evidence has been presented for episodic memory dysfunction. In contrast, in high-dissociative subjects increased performance has been found for episodic memory and dual task performance. These findings have been linked to changes in working memory capacity. METHOD: In the present study, the authors sought to extend these findings by using functional magnetic resonance imaging during performance of two parametric working memory tasks. We tested 21 healthy low- and high-dissociative participants. RESULTS: High-dissociative participants performed slightly better during both tasks. Imaging data showed that both groups activated similar networks for both tasks, i.e. (bilateral) dorsolateral (DL) and ventrolateral prefrontal cortex (PFC), parietal cortex, and supplementary motor area. Group x task interactions were found in the high-dissociative group in L DLPFC and L parietal cortex; in the low-dissociative group in R fusiform gyrus. The differences in the high-dissociative group were independent from performance differences, implying that high-dissociative subjects generally recruit this network to a greater extent. CONCLUSIONS: These results confirm earlier findings using a verbal WM task in high-dissociative participants, and are compatible with the conceptualization of non-pathological dissociation as an information-processing style, characterized by distinct attentional and mnemonic abilities.  相似文献   
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Biotinidase is responsible for recycling the vitamin biotin from biocytin that is formed after the proteolytic degradation of the biotin- dependent carboxylases. We have identified a deletion/insertion mutation within exon D of the human biotinidase gene in a child with biotinidase deficiency. The mutation causes a frame shift and premature termination which are predicted to result in a truncated protein. We propose that the mutation occurred during DNA replication by either of two mechanisms. Both mechanisms involve formation of a quasipalindromic hairpin loop in the template and dissociation of DNA polymerase alpha. This mutation supports the formation of palindromic structures as a possible cause of deletions in eukaryotes, and supports the proposal, derived from in vitro studies, that polymerase alpha may preferentially arrest or dissociate at specific template sequences.   相似文献   
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