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31.
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   
32.
PROBLEM: To compare depressive symptoms in children with attention deficit hyperactivity disorder (ADHD) to those in healthy children, and to explore the influence of individual and family factors on level of depression. METHODS: Individual interviews with 68 children, ages 7 to 12 years, in order to complete the Children's Depression Inventory. FINDINGS: Children with ADHD reported significantly more depressive symptoms than did children without ADHD; 14.7% of children with ADHD reached the threshold of a 19 point score, which suggests clinical depression. No significant effects of individual and family factors on level of depression were found. CONCLUSIONS: Children with ADHD are more inclined to experience depressive symptoms than are healthy children. To plan appropriate interventions, nurses evaluating and working with children with ADHD should always consider a possible coexistence of depressive symptoms.  相似文献   
33.
The substitution of leucine for valine at amino acid position 34 of the factor XIII gene is commonly referred to as FXIII Val34Leu polymorphism. The homozygous leucine/leucine genotype has been reported to confer protection against venous thromboembolism, but previous studies have not evaluated a population limited to those with idiopathic venous thromboembolism. The primary objective of the study was to determine whether the FXIII Val34Leu polymorphism is independently associated with the occurrence of idiopathic venous thromboembolism. We prospectively enrolled consecutive patients with at least one objectively confirmed idiopathic venous thromboembolism. Friends of cases were recruited as controls and matched to cases by sex, ethnicity, and age. All participants were tested for the FXIII Val34Leu polymorphism in addition to several well-known thrombophilias. Data from 309 cases and 306 controls were analyzed. The FXIII leucine/leucine genotype was present in 4.9% of cases and 6.5% of controls. An adjusted odds ratio of 0.59 (95% confidence interval, 0.25-1.38) was found for the recessive model and 0.69 (95% confidence interval, 0.46-1.02) for the dominant model. Our results do not support an independent association of the FXIII Val34Leu polymorphism with idiopathic venous thromboembolism in our Caucasian Canadian study population.  相似文献   
34.
The present study investigated the expression of c-erbB-2 in 59 meningiomas, including different histological subtypes and anaplastic variants, by immunocytochemistry and molecular biological techniques. Immunohistochemistry using the monoclonal antibody FWP-51 directed against c-erbB-2-encoded oncoprotein gp185 demonstrated variable degrees of immunoreactivity in all meningiomas. The intensity of immunostaining correlated with the degree of expression as assessed by Western analysis in 28 meningiomas using polyclonal antiserum 21N. There was no correlation between the degree of expression and histological variants. Immunoreactivity of all menigiomas was distinctly less intense, however, than that of the human breast cancer cell line SK-BR-3, and slightly lower than that of brain metastases of breast and ovarian carcinomas that served as positive controls for both methods. By Southern analysis all meningiomas showed a single copy of the c-erbB-2 gene. Non-neoplastic arachnoid cap cells also exhibited c-erbB-2 expression and the degree of immunoreactivity was comparable with the majority of meningiomas. These data argue against an overexpression of c-erbB-2 in meningiomas, but rather indicate a cell-type-specific constitutive expression of the c-erbB-2 gene product in meningiomas and their putative progenitor cells. Since a subgroup of meningiomas is known to express progesterone receptors (PR), gp185 immunoreactivity was compared to the hormone receptor status using monoclonal antibody KD68. Fifty-six percent meningiomas showed PR immunoreactivity, but there was no statistically significant correlation with the degree of gp185 expression.This study was supported by a grant of the Tumorzentrum Heidelberg/Mannheim (M.K., No. 10028060)  相似文献   
35.
Background - A case of primary thyroid T cell lymphoma leading to lethal tracheal perforation during chemotherapy is described.  相似文献   
36.
Rehabilitation for geriatric patients, as well as rehabilitation for patients with a chronic disease, strives to mobilize individuals' residual capacity for optimal function in their usual environment. It is clear from observational studies that chronic dialysis patients often experience marked limitations in physical functioning, and these limitations tend to increase with patients' age. However, both prospective studies and controlled trials conducted with elderly persons demonstrate that muscle strengthening and cardiovascular exercise are related to improved physical functioning, and there is evidence that dialysis patients can also benefit from many of these interventions. Inpatient rehabilitation in a specialized geriatric unit has been shown to be associated with better functional outcomes and decreased need for institutionalization among elderly persons; the process of comprehensive geriatric assessment may also have beneficial outcomes. More controlled studies are needed in order to better specify the effectiveness of various geriatric interventions, for elderly subjects in general and for elderly dialysis patients specifically.  相似文献   
37.
The development of a unifying framework for conceptualizing the commonalities in various forms of substance abuse must encompass the data base focused upon the stimulus functions of drugs. In the first instance, for example, the research on drug self-administration has provided convincing evidence of a remarkable concordance between laboratory animals and human substance abusers in the reinforcing stimulus functions of a range of chemical agents. The recognition of these cross-species and cross-drug generalities has radically changed conceptualizations of substance abuse from a reactive to a more active process and has encouraged the kind of functional analysis of drug-seeking and drug-taking that has proven productive and useful in the study of other behavioral interactions. In this regard as well, recent refinements in the analysis of the discriminative stimulus functions of drugs have provided a more comprehensive basis for characterizing a chemical agent's spectrum of action and evaluating its abuse liability. While the correlation between the discriminative stimulus functions and the reinforcing stimulus functions is remarkably high for some drug classes, there are notable exceptions. Finally, the assessment of abuse liability requires an analysis of the eliciting stimulus functions of drugs as reflected by the physiological and behavioral changes, both acute and chronic, that follow drug administration. The methods used to evaluate both physiological dependence and behavioral toxicity in relationship to sensory and motor effects for a range of abused drugs have depended heavily upon an assessment of the eliciting stimulus functions of such compounds.  相似文献   
38.
The authors systematically evaluated the frequency patterns of cocaine use in 85 cocaine-dependent outpatients and found four patterns of use: continuous (27%), intermittent patterned (35%), intermittent nonpatterned (25%), and occasional (13%). Few subjects reported consistent cycling between binges and crashes. There were no significant differences in patterns of use associated with gender, race, educational level, route of administration, or recency of heroin use. Continuous users and occasional users were older than intermittent users. Because different contingencies may control patterned vs. nonpatterned cocaine use, pattern of use may have implications for treatment, even in individuals reporting similar amounts of cocaine use.  相似文献   
39.
The in vitro permeabilities of Caco-2 monolayers and permeabilities in tissue sections from colon of monkey, rabbit, and dog were compared using a series of compounds. The selected compounds differed in their physicochemical properties, such as octanol/water partition coefficient, water solubility, and molecular weight. Their structure included steroids, carboxylic acids, xanthins, alcohols, and polyethylene glycols. A linear permeability relationship was established between Caco-2 and colon tissue from both rabbit and monkey. The results suggest that Caco-2 is twice as permeable as rabbit and five times as permeable as monkey colon. However, no clear relationship could be established between Caco-2 monolayers and dog colon permeability. A relationship between permeability in Caco-2 monolayers and human absorption was found. The results suggest that within certain limits, permeability of Caco-2 monolayers may be used as a predictive tool to estimate human drug absorption.  相似文献   
40.
This paper concerns the diagnostic classification of nonaffective acute remitting psychosis (NARP), which we also term acute brief psychosis. We argue that NARP can be delineated from both schizophrenia and the affective psychoses and considered as a single diagnosis. As indicated by the term NARP, four criteria would be central to the diagnosis: 1. nonaffective, 2. acute onset (over less than two weeks), 3. recovery within a brief duration (less than six months), and 4. psychosis broadly defined. We review the rationale and the empirical evidence for this proposed classification.  相似文献   
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