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851.
The binding of charged substances from external aqueous media to hair has been investigated through the use of fluorescence microscopy. Eleven hair samples, reflecting various ethnic groups and cosmetic treatments, were tested. Rhodamine 6G, a cationic dye representative of drugs such as cocaine and opiates, showed incorporation throughout the hair of all samples except one. In contrast, fluorescein, an anionic dye representative of drugs such as THC carboxylic acid, was not readily incorporated. The incorporation of rhodamine 6G was faster for chemically 'straightened' and bleached African-American female hair than for untreated hair. Incorporation of rhodamine 6G followed a pH dependence, but an ionic strength dependence could not be established. These studies support three postulates: (1) electrostatic interactions explain the preferential binding of cationic drugs of abuse to hair; (2) the hair matrix, or the non-helical portion of hair, is accessible to external solutions and thus subject to contamination; and (3) cosmetic treatments may alter the helical portion of hair thereby increasing its accessibility to external contamination. 相似文献
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The authors wished to study some of the internal psychological dynamics of achievement in a nonpatient identified high school population. Questionnaires were administered to the Grade 13 students and their parents in a large high school. A number of students whose achievement and educational plans were not congruous with their general background were selected for interview. The findings suggest that a wide variety of ages and developmental stages can be discerned as critical points in the development of a student's attitude toward higher education. These students have many values in common, and their values appear related to a positive or negative identification with parental values. The students themselves show a wide range of personality integration. They relate in a special way to a wide variety of teachers' personalities.Received M.D. from University of Alberta, Edmonton, in 1969 and completed specialty training in psychiatry at University of Toronto in 1974. Main interests include psychoanalysis, community psychiatry, and currently antabuse implants.Received M.D. from University of Toronto in 1960, D. Psych. from University of Toronto in 1963, C.R.C.P.(c) in 1965, and F.R.C.P. in 1972. Main interests include adolescent psychiatry, psychoanalysis, psychiatric residency training programs, and mental health delivery systems. 相似文献
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This bibliography covers publications noticed between Septemberand November, 1953. It has been compiled with the co-operationof Professor T. Heyse (lately of the Belgian Ministry of Colonies)and Miss Ruth Jones (International African Institute). 相似文献
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