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BACKGROUND: Oral hairy leukoplakia (OHL) may be an indicator of the progression of Human Immunodeficiency Virus (HIV)-induced immuno-depression, and the evaluation of risk factors leading to OHL is important in the management of these HIV-infected patients. However, there are few studies that analyze risk factors leading to OHL in the Brazilian population. The aim of this case-control study is to present data about prevalence rates and risk factors leading to OHL in a sample of HIV-infected adults in Brazil. METHODS: This case-control study included 111 HIV-infected patients treated at a clinic for sexually transmitted diseases and HIV. In the initial examinations with dentists, variables were collected from all patients. Diagnosis of OHL was performed in accordance with the International Classification System and cytological features. The Fisher and the chi-squared tests were used for statistical analysis. The proportional prevalence and odds ratio were estimated. RESULTS: Outcome presented a positive, statistically significant association among the presence of OHL and viral load of 3000 copies/mul or greater (P = 0.0001; odds ratio (OR) = 5.8), presence of oral candidiasis (P = 0.0000; OR = 11.1), previous use of fluconazole (P = 0.0000; OR = 24.6), and use of systemic acyclovir (P = 0.032; OR = 4.3). Antiretroviral medication presented a negative, statistically significant association with the presence of OHL (P = 0.002; OR = 8.4). CONCLUSIONS: Prevalence of OHL was 28.8%. Viral load, oral candidiasis, previous use of fluconazole, and systemic acyclovir were determined to be risk factors for OHL. Antiretroviral medication proved to be protective against the development of OHL.  相似文献   
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PurposeTo analyze the electroclinical features, aetiology and outcome in patients with normal neurological examination and psychomotor development who presented seizures during a mild gastroenteritis (MG).Patients and methodsEvaluation of the clinical charts of 22 patients who were assessed in the Neurology Department, Hospital Nacional de Pediatría Prof. Dr. JP Garrahan between 1999 and 2007.ResultsTwelve patients were boys and 10 were girls, the age of onset ranged from 5 to 26 months, and the median age was 10 months. Rotavirus antigen test in stool was positive in 9 of 18 studied patients. The seizures were brief, focal with secondary generalization in 15 patients (68.5%), apparently generalized in 5 (22.5%) and focal in two (9%). Seven of the patients (35%) had more than one seizure in 24 h. The interictal EEG was normal in all patients. Neuroradiological studies were performed in 19 patients with a normal result. No patient was put on long-term treatment with antiepileptic drugs. Four patients had subsequent mild gastroenteritis and two of them presented convulsions during the disease. After between 12 and 67 months of follow-up, all patients had normal psychomotor development and neurological examination.ConclusionsIn this study we confirmed the association of benign infantile seizures (BIS) and MG with or without rotavirus. The identification of this entity allows avoiding unnecessary complementary studies and treatment with antiepileptic drugs.  相似文献   
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OBJECTIVE: The objective of this study was to radiographically quantify bone density and bone height preservation in tooth extraction alveolus filled with xenograft. STUDY DESIGN: The maxillary and mandibular fourth deciduous molars and fourth premolars of 6 minipigs were removed. Randomly, in 3 animals the right side was used as the test side and in the other 3 animals the left side was the test side. Intraoral radiographs were performed to compare the condition at the initial time and 3 months later. Measurements of bone height and bone density were performed using KS300 (Zeiss) software. RESULTS: After 3 months, there was a statistically significant smaller bone height loss for the test group. The test group presented a statistically greater bone density immediately after tooth extraction. However, after 3 months there was no statistically significant difference between the groups. CONCLUSIONS: The results suggest that treatment of postextraction alveolus with xenograft can preserve bone height initially but differences in bone density compared to when no xenograft is used are not sustained.  相似文献   
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Acute myelogenous leukemia (AMU is a hematologic disorder that is characterized by an abnormal proliferation of immature myeloid cells. Granulocytic sarcomas are clusters of leukemic myeloid cells that may develop as a result of AML. Oral manifestations of AML are common and often involve enlargements of the gingiva and/or mucosal tissue from direct leukemia cell infiltration. We describe the case history of a 50-year-old man who had an ulcera-tive lesion of the oral mucosa that was determined to be a granulocytic sarcoma of AML-M0 subtype. The combination of both the subtype and clinical presentation of the leukemia makes this presentation unusual, and to the best of our knowledge, of a type that has not been previously reported in the literature.  相似文献   
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Background. Accepted practices of informed consent often result in suboptimal patient understanding of research studies.Methods. This pilot study aimed to assess trial-specific tailored materials, compared to a widely used generic booklet about clinical trials, randomly assigned to 118 candidates for cancer clinical trials. Study outcomes were: satisfaction with decision-making; satisfaction with materials; and subjective understanding of the clinical trial.Results. There were no major differences between groups. Participants rated tailored materials higher as a useful reference.Conclusions. Trial-specific materials hold utility for reference during clinical trials. Studies of informed consent are feasible, although important factors limit research.  相似文献   
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Atrophy of salivary glands may occur by ductal obstruction caused by calculus, infection or neoplastic processes, or as consequence of systemic diseases and aging. In the present work, we have used histochemical methods to study the expression of elastic and collagen fibers during experimental atrophy of the submandibular gland of mice. Glandular atrophy was accompanied by a rapid increase in collagen deposition in both septal and intralobular regions. The expression of elastic fibers was not significantly altered during atrophy; a discrete increase of elastic fibers was noted only around ductal structures. The results showed that experimental ductal obstruction is a useful in vivo model to study molecular events that take part in the remodeling of the extracellular matrix during atrophy of salivary glands.  相似文献   
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