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PurposeThe first purpose was to identify barriers to physical activity that students in grade seven through first-year university experienced. A second purpose was to classify barriers using an ecological framework and to examine the pattern of barrier categories (i.e., intrapersonal, interpersonal, institutional, community, public policy, and physical environmental) and specific barrier types as grade increased. The use of an ecological model addressed limitations in prior research revolving around the identification of salient barriers in a manner that makes the design of effective interventions difficult.MethodsParticipants in grades 7–8 (n = 35), 9–10 (n = 67), 11–12 (n = 80), and the freshmen year of university (n = 109) listed barriers to physical activity on an open-ended measure.ResultsFindings revealed a trend for the average number of barriers reported per student to increase as grade in school increased. First-year university students reported significantly more barriers than all other grade groupings. The frequency of barriers reported within the ecological categories was dependent on the specific grade groupings. Further, within each ecological category, distinct barriers were reported across the different grade groupings.ConclusionsFindings highlight the utility of using an ecological model to categorize barriers, rather than simply classifying barriers as internal or external to an individual, as done in prior research. Understanding the pattern of ecologically based barrier categories and specific types of barriers will help to inform the content of future research and interventions designed to alleviate salient barriers to physical activity.  相似文献   
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Disrupted-In-Schizophrenia-1 (DISC1) is a promising candidate gene for schizophrenia (SZ) and bipolar disorder (BP), but its basic biology remains to be elucidated. Accumulating genetic evidence supports that DISC1 is associated with some aspects of cognitive functions relevant to SZ and BP. Here, we provide a summary of the current updates in biological studies of DISC1. Disrupted-In-Schizophrenia-1, preferentially expressed in the forebrain, has multiple isoforms with potential posttranslational modifications. Disrupted-In-Schizophrenia-1 protein occurs in multiple subcellular compartments, which include the centrosome, microtubule fractions, postsynaptic densities, actin cytoskeletal fractions, the mitochondria, and the nucleus. Recent studies have clarified that DISC1 mediates at least centrosome-dynein cascade and cyclic adenosine monophosphate (cAMP) signaling. Furthermore, both cytogenetic and cell biological studies consistently suggest that an overall loss of DISC1 function (either haploinsufficiency or dominant-negative, or both) may be associated with SZ and BP. On the basis of these findings, production of DISC1 genetically engineered mice is proposed as a promising animal model for SZ and BP. Several groups are currently generating DISC1 mice and starting to characterize them. In this review, the advantages and disadvantages of each animal model are discussed.  相似文献   
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Early Intervention for Trauma: Current Status and Future Directions   总被引:5,自引:0,他引:5  
Although psychological debriefing (PD) represents the most common form of early intervention for recently traumatized people, there is little evidence supporting its continued use with individuals who experience severe trauma. This review identifies the core issues in early intervention that need to be addressed in resolving the debate over PD. It critiques the available evidence for PD and the early provision of cognitive-behavioral therapy (CBT). Based on available evidence, we propose that psychological first aid is an appropriate initial intervention, but that it does not serve a therapeutic or preventive function. When feasible, initial screening is required so that preventive interventions can be used for those individuals who may have difficulty recovering on their own. Evidence-based CBT approaches are indicated for people who are at risk of developing posttraumatic psychopathology. Guidelines for managing acutely traumatized people are suggested and standards are proposed to direct future research that may advance our understanding of the role of early intervention in facilitating adaptation to trauma.  相似文献   
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To determine the utility of the lateral view of the chest in emergency department patients, records of all patients who had had 2-view chest x-rays ordered in the emergency department were reviewed retrospectively. A study radiologist recorded a reading of the posteroanterior (PA) radiograph alone. The lateral radiograph was then provided, along with the PA view, and a second reading was recorded. A comparison was then made between the first and second readings.A total of 417 sets of x-rays were included. The PA view alone successfully diagnosed or suspected 92% of pulmonary nodules, 95% of effusions, 97% of cases of emphysema, 98% of pneumonias, and 100% of cases of cardiomegaly, pulmonary edema, interstitial pulmonary disease, and atelectasis.In the emergency department patient population, lateral views of the chest have minimal diagnostic yield and therefore may be used selectively to safely decrease the amount of breast radiation exposure to young women.  相似文献   
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D-cycloserine augmented exposure therapy for obsessive-compulsive disorder.   总被引:1,自引:1,他引:0  
BACKGROUND: D-cycloserine (DCS), a glutamatergic partial N-methyl-d-aspartate (NMDA) agonist, can facilitate extinction learning related to cued fear in animals and humans. We predicted that DCS would accelerate obsession-related distress reduction in patients with obsessive-compulsive disorder (OCD) undergoing extinction-based exposure therapy. METHODS: We administered DCS (125 mg) or placebo in a double-blind fashion to individuals with OCD approximately 2 hours before each exposure session. RESULTS: D-cycloserine decreased both the number of exposure sessions required to achieve clinical milestones and the rate of therapy dropout. After four exposure sessions, patients in the DCS group reported significantly greater decreases in obsession-related distress compared with the placebo group; however, after additional sessions, the placebo group tended to catch up. CONCLUSIONS: D-cycloserine augmentation has the potential to increase the efficiency, palatability, and overall effectiveness of standard exposure therapy for OCD.  相似文献   
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