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Amyloid is characterized by its fibrillary ultrastructure, and more than 20 proteins have been described to date as possible precursors. Among them, insulin and enfuvirtide represent the only medications described as amyloidogenic substances. We describe two diabetic patients, who were undergoing long‐standing subcutaneous insulin treatment, who developed subcutaneous nodules at the sites of insulin injections. Histopathologic examination showed the presence of eosinophilic and amorphous masses in deep dermis, which stained positive with Congo red, amyloid P substance and anti‐human insulin antibody. Whether the type of injected insulin played a role or not in the pathogenesis of the process is still uncertain, because all described patients used both fast‐acting and slow‐acting insulins at the same injection sites. Our second case showed nodular insulin‐derived amyloid tumors only at the sites where exclusively fast‐acting insulin was injected, which supports the notion that fast‐acting insulin may also be the cause of this disorder. Insulin‐derived nodular amyloidosis is probably underdiagnosed because of the small body of literature in comparison with the prevalence of insulin dependent diabetic patients. This underdiagnosis probably is because of its clinical similarity with the lesions of lipohypertrophy at the sites of insulin injections, which is rarely biopsied.  相似文献   
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The aim of this study was to evaluate the usefulness of spectrometrically measured colour parameters of teeth for age estimation in living adults. A total of 329 teeth were selected (162 upper central incisors and 167 upper canines) from 52 men and 50 women aged between 20 and 86 years. Colour measurements were performed in vivo on the vestibular surface of the teeth using a portable contact Spectro-color device. Colorimetric variables (L*, a*, b*), chromaticity coordinates (x, y, z), and indexes of whiteness (WIC, Z%, WI) and yellowness (YI) were calculated. The accuracy of colour values to estimate the age was determined by Receiver Operating Characteristic analysis. A more powerful age discrimination was obtained with upper incisors than with upper canines. Areas under the ROC curve ranged from 0.7 to 0.8 for all dental colour parameters measured in upper central incisors except for the variables L* and Z%, with sensitivity values ranging from 56% to 93% and specificity values from 38% to 92%. We conclude that spectrophotometric dental colour measurement may be an objective and useful tool to estimate age and meets medical ethical standards for application in living adults. However, further research is needed to study the effect of ethnicity and other factors on tooth colour.  相似文献   
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Liver transplantation offers patients with terminal liver disease an effective treatment accompanied by excellent quality of life, but it also has complications, such as hepatic artery thrombosis and development of ischemic cholangiopathy, described in 3%–17% of patients. It is a very important cause of morbidity and mortality. The objective of this report was to analyze the efficacy of the treatment they received in relation to the development of ischemic cholangiopathy and a comparative survival analysis and to propose prophylactic measures for high-risk patients.  相似文献   
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Rural cancer disparities are increasingly documented in the USA. Research has identified and begun to address rural residents’ cancer knowledge and behaviors, especially among women. Little, however, is known about rural female residents’ awareness of cancer inequities and perceived contributing factors affecting them and their families. The purpose of this study was to address these gaps in the literature via a secondary analysis of qualitative needs assessment in Illinois’ rural southernmost seven counties, a geographic region with relatively high rates of cancer incidence, morbidity, and mortality. A convenience sample of 202 rural adult female residents was recruited and participated in 26 focus groups, with 3–13 women per group. Inductive content analysis, guided by the principle of constant comparison, was used to analyze the qualitative data. Most respondents indicated their awareness of disproportionate cancer burden in their communities. Individual-level behaviors and environmental toxins were identified as contributing factors. Interestingly, however, environmental toxins were more often discussed as factors contributing to geographic differences, whereas individual-level behaviors were noted as important for overall cancer prevention and control. This study provides important insight into female rural residents’ perspectives and offers novel venues for educational programs and research in the context of communication to eliminate disparities.  相似文献   
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