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A comparative histopathologic study is made between the hypopigmented and hyperpigmented skin lesions of pityriasis versicolor and normal skin areas utilizing histochemical stains and electron microscopy. There were no differences found between the population of Dopa-positive melanocytes within the hypopigmented and hyperpigmented lesions and the normal skin areas. The total epidermal pigmentation was diminished in hypopigmented lesions. The keratin layer was found to be significantly thicker in hyperpigmented lesions and contained more organisms. In hypopigmented lesions, melanocytes contained fewer and smaller melanosomes and exhibited signs of degenerative cellular changes.  相似文献   
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Background: Despite numerous studies examining the association between competitive sports participation and substance use behaviors among adolescents and young adults, the use of standardized measures to assess potential substance use disorders has been largely neglected. The objective of this study was to examine if past involvement in interscholastic sports (competitive school-sponsored sports) was associated with potential substance use disorders in young adulthood. Methods: Data for this study were taken from the Student Life Survey (SLS). A total of 3442 young adults participated in the SLS during the spring semester in 2013, with 74% of males and 71% of females indicating participation in interscholastic sport during high school. Results: Respondents who participated in interscholastic sports during high school had higher odds of positive screens for potential alcohol use disorders when compared with their peers who did not participate in interscholastic sports. No association was detected between interscholastic sports participation and potential drug abuse disorders. Moreover, previous involvement in certain types of sports was found to be associated with positive screens for potential alcohol use disorders (i.e., crew and football) and positive screens for potential drug abuse disorders (i.e., lacrosse) among the sample of young adults. Conclusions: School and community sport organizations should be aware of the potential link between sports participation and potential substance use disorders, and may consider brief substance use screeners during yearly physicals to monitor potential substance use problems among athletes.  相似文献   
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A facile single-step synthesis was performed to cross-link chitosan with thiocarbohydrazide to yield thiocarbohydrazide-chitosan (TC-Cht) which was for the first time evaluated as an inhibitor for corrosion of stainless steel in 3.5% NaCl solution. A comprehensive electrochemical analysis employing electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), and cyclic voltammetry (CV) was undertaken and showed that the TC-Cht acts by adsorption on the steel surface and exhibits mixed type behavior with predominantly cathodic nature. The adsorption of TC-Cht molecules on the surface of stainless steel followed the Langmuir isotherm. The TC-Cht showed a high inhibition efficiency of >94% at 500 mg L?1 concentration. Surface investigation using SEM and EDX supported the inhibitor adsorption on the steel surface.  相似文献   
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Measuring outcomes of treatments for psychosis such as needs and the quality of the therapeutic relationship is important in research and routine care. However, evidence on the validity of existing outcome measures is limited. We aimed to test the convergent, discriminant, and predictive validity of two widely used patient- and clinician-rated measures of needs and the therapeutic relationship. Multitrait-multimethod (MTMM) analysis was conducted on the Camberwell Assessment of Need Short Appraisal Schedule (CANSAS) and the Helping Alliance Scale (HAS), both the clinician (CANSAS-C, HAS-C) and patient (CANSAS-P, HAS-P) versions, in a pooled sample of 605 psychotic patients and their clinicians. CANSAS-C and CANSAS-P items loaded substantially into one common unmet needs factor. By comparison, substantial factor loadings were found for HAS-C and HAS-P items on two separate clinician- and patient-rated therapeutic relationship factors. Common unmet needs and clinician-rated therapeutic relationship factors significantly predicted reduced psychiatric in-patient days. Our findings support the convergent validity of the CANSAS, discriminant validity of the HAS, and predictive validity of CANSAS and HAS-C. The findings may inform the use of CANSAS and HAS as psychosis outcome measures in research and routine care.  相似文献   
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