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101.
Moral reasoning in dental hygiene students   总被引:1,自引:0,他引:1  
Sixty-five students participated in a study designed to identify the level of moral reasoning of dental hygiene students. Comparisons were made with typical college students and a normative group composed of individuals representing a cross-section of ages and educational levels. The relationships among level of moral reasoning and clinical performance, other selected academic measures, and cognitive style were also assessed. The results indicated that post-certificate dental hygiene students reasoned about moral dilemmas at a higher level than the normative group and at the same level as the college student group. In addition, clinical performance, National Board Dental Hygiene Examination scores, Dental Hygiene Aptitude Test (reading scores), high school rank, and cognitive style correlated positively with level of moral reasoning and specific stages of moral development for postcertificate students.  相似文献   
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Microcirculation of the dental pulp in health and disease   总被引:1,自引:0,他引:1  
S Kim 《Journal of endodontics》1985,11(11):465-471
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There is a lack of correlation between specific properties of hydroxyapatite coating surfaces, osseointegration processes, and implant success. The aim of this study was to evaluate the relationship between well-characterized structural and chemical properties of radio-frequency sputtered calcium phosphate (CaP) coatings and their dissolution behavior. Sputtered CaP coatings were evaluated as-sputtered (non-heat treated) or after 1 hour of postsputter heat treatments at 400 degrees C or 600 degrees C. All coatings were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and contact angle measurement. The dissolution behavior of CaP coatings in the presence and absence of proteins was also investigated. It was observed from this study that as-sputtered CaP coatings were amorphous. The 400 degrees C heat-treated CaP coatings exhibited low crystallinity (1.9% +/- 0.4%), whereas the 600 degrees C heat-treated CaP coatings were highly crystalline (67.0% +/- 2.4%). The increase of Ca/P ratio, PO4/HPO4 ratio, and the number of PO4 peaks were observed to be consistent with the increase in heating temperature and the degrees of coating crystallinity. Phosphorus ions released from CaP coatings decreased with the increase of crystallinity of CaP coatings. In addition, immersion of CaP coatings in media containing proteins resulted in an increase in P ions released as compared with coatings immersed in media without proteins. It was concluded that the degree of CaP coating crystallinity can be controlled by varying the postdeposition heat-treatment temperature. It was also concluded that, aside from coating crystallinity, dissolution and reprecipitation of the coatings can be controlled by knowing the presence of proteins in the media and PO4/HPO4 ratio within the coatings.  相似文献   
109.
A 17-year-old white boy with signs, symptoms, and family history of angiokeratoma corporis diffusum universale, Anderson-Fabry disease (AFD), developed recurrent and then persistent swelling of both lips, erythematous hyperplastic gingivae, and a pebbled tongue. Positive blood findings were raised serum IgE, decreased T-cell level, and increased B-cell level. Histopathology of the gingiva showed noncaseating granulomas with multinucleate giant cells containing Schaumann bodies and large plasma-cell infiltrates in which immunofluorescence demonstrated immune globulins of several classes. Electron microscopy and histochemistry demonstrated ceramide in the vasculature. No glycolipid was found in the macrophages or giant cells of the granulomas which, in contrast, resembled sarcoid reactions. Plasma cells with Russell bodies and immune reaction-induced degranulation of mast cells were also identified. The pathogenesis of the oral findings possibly relates to altered immune reactivity associated with damage to the microvasculature analogous to that in Melkersson-Rosenthal syndrome.  相似文献   
110.
OBJECTIVE: The aim of the study was to investigate the relationship between oral Candida carriage and the secretor status of blood group antigens. STUDY DESIGN: Unstimulated whole saliva and oral rinse samples were obtained from 180 healthy subjects. These samples were plated on Sabouraud's dextrose agar media to determine oral Candida carriage. Sodium dodecylsulfate polyacrylamide gel electrophoresis and immunoblotting were performed on whole saliva samples to determine the secretor status of blood group antigens. RESULTS: The oral Candida carriage rate was found to be 45.0%. The sensitivity of the concentrated rinse culture proved to be superior. Oral Candida carriage was not significantly related to the blood group or secretor status of ABH or Lewis antigens. No significant relationship was found between oral Candida carriage and salivary flow rate. However, smoking affected oral Candida carriage. CONCLUSION: Oral Candida carriage in healthy individuals is not significantly related to blood group or secretor status.  相似文献   
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