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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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This case study illustrates the chronic nature of hyperlipidemia type IIa and the important contribution of the nurse in helping the client adjust life style, manage complex health regimes, and cope with the uncertainty of disease progression and its associated risks.  相似文献   
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Research investigating predictors of risky sexual behavior of rural MSM is sparse, even though the prevalence of HIV in rural areas has increased. This study explored two sets of predictors of 93 rural MSM's levels of risky sexual behavior: mental health variables and stigma emanating from men's family members, health care professionals, and people in the rural communities in which they live. Over 47% of the men were found to be at modified high to high risk. Logistic regression using a continuation logit model was used to test the relationship of the predictor variables and the four levels of risk. Findings indicate that self-esteem was predictive of the highest sexual risk behavior but not lower levels of risk. Stigma was predictive of modified high sexual risk when compared to low and no risk categories. No variables differentiated men at low risk from men at no risk.  相似文献   
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A numerical model based on Navier-Stokes equations was used in conjunction with an experimental model in rabbits to study the effects of acute intracranial hypertension on basilar artery blood flow velocity. The hypertension was induced by pressure transmission via an epidural pressure sensor inserted into a parietal intracranial opening. A critical value of half of the diastolic arterial pressure for the intracranial cerebral pressure was determined by both numerical and experimental models. At this intracranial cerebral pressure level, the total input resistance and total input compliance, determined by the numerical model, exhibited an increase of 27% and 10%, respectively, and the tissular compliance a decrease of 25% from their physiologic baseline values. When the intracranial cerebral pressure reaches the level of the diastolic arterial pressure, a zero diastolic flow is observed into the cerebral vascular system. This study validates the theoretical model, which could be used in assessing intracranial cerebral pressure noninvasively in humans when O2 pressure can be stabilized.  相似文献   
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