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71.
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Sixty isolates of Mycobacterium tuberculosis identified as multidrug-resistant (MDR) at a reference laboratory in Rio Grande do Sul State during the years 1999 and 2000 were analyzed using the IS6110-restriction fragment length polymorphism (RFLP) technique. We also genotyped 202 susceptible strains to compare the genotyping results, as well as the clinical and demographic data. Spacer oligotyping (spoligotyping) analysis was performed for isolates presenting low IS6110 copy number. Patients with identical DNA pattern strains were considered clustered. From 262 isolates, 94 (36%) belonged to 20 distinct RFLP clusters, and after spoligotyping analysis, 89 of the isolates (34%) remained in cluster. MDR isolates did not differ statistically in clustering proportion from susceptible strains. A significant association between the occurrence of MDR and previous tuberculosis (TB) treatment was observed (p < 0.001), as well as failure on TB treatment (p < 0.001). Human immunodeficiency virus (HIV)-positive patients were associated with susceptible tuberculosis (p = 0.024). We also identified that unmarried patients were more likely to develop TB due to recent transmission than married patients (p < 0.005). The introduction of directly observed therapy short-course (DOTS) strategy will be important in decreasing default and failure rates and avoiding the development of new MDR strains.  相似文献   
73.
Caveolae are cell plasma membrane microdomains implicated in organizing and concentrating many signaling molecules. In the lung, caveolae are in endothelium, smooth muscle, fibroblasts, and pneumocytes. Caveolin is the main structural protein of caveolae. Caveolin 1 is down-regulated in transformed cells and may be a tumor suppressor protein. Caveolin 2 is coexpressed and hetero-oligomerizes with caveolin 1. Because the cells of the plexiform lesions in severe pulmonary hypertension (PH) are phenotypically altered, we wondered whether these cells lack caveolin. We now demonstrate by immunolocalization that while caveolin is expressed in lung endothelial, smooth-muscle, and alveolar septal cells, its expression is absent or decreased in plexiform lesions and in some muscularized precapillary arterioles. In contrast, Western blot analysis of total lung extracts from patients with severe PH shows no significant reduction in caveolin. Similar to the human lung tissue, a rat model of severe PH demonstrates absent-to-decreased caveolin expression in the complex vascular lesions. Additionally, it appears that caveolin and heme oxygenase 1 (HO-1) [a heat shock protein] are co-expressed since HO-1 expression parallels caveolin expression in vascular lesions. We propose that loss of caveolin expression in the cells of the complex vascular lesions in severe PH reflects the proliferating and apoptosis-resistant nature of these cells.  相似文献   
74.
Although there are specific guidelines regarding the treatment of dyslipidemia in highly risk patients, these recommendations are usually inadequately followed. The aim of this study is to investigate risk factors in patients with increased cardiovascular risk currently treated in Brazil and Venezuela. Medical charts of 412 patients were selected in 4 institutions. Patients were divided into groups according to the use of lipid-lowering drugs (LLD), particularly statins. Patients who did not use LLD showed higher levels of total cholesterol (p< 0.001), LDL cholesterol (p< 0,001) and HDL cholesterol (p< 0.001), besides lower levels of triglycerides (p< 0.001). The use of statins was associated with a decrease in levels of total cholesterol (from 251.0 +/- 40.0 to 196.0 +/- 46.0), LDL cholesterol (from 168.0 +/- 36.0 to 116.0 +/- 39.0), HDL cholesterol (from 51.0 +/- 46.0 to 46.0 +/- 12.0) and triglycerides (from 181.0 +/- 120.0 to 160.0 +/-79.0). Finally, only a small percentage of patients, even those under treatment with LLD, showed cholesterol levels according to currently available guidelines. Therefore, although the guidelines for the treatment of dyslipidemia are widely known, only a small percentage of patients achieve adequate levels of cholesterol. It is necessary to decrease lipid levels of these patients by increasing the dose of the statins or using a second drug.  相似文献   
75.
This study compared the clinical performance of a nanofilled resin composite for posterior restorations with 2 microhybrid and 1 packable composite after 12 months of clinical service. Forty-two patients with at least 5 Class I or II restorations under occlusion were enrolled in this study. A total of 148 restorations were placed, 25% for each material (Filtek Supreme, Pyramid, Esthet-X or Tetric Ceram). Two calibrated operators placed all restorations, according to the manufacturers' instructions. One week later, the restorations were finished/polished. Two independent examiners evaluated the restorations at baseline and after 12 months according to the USPHS modified criteria. All patients attended the 12-month recall and 148 restorations were evaluated. Friedman repeated measures analysis of variance by rank and Wilcoxon sign-ranked test for pair-wise comparison was used for data analysis (alpha=0.05). All materials showed only minor modifications, and no differences were detected between their performance at baseline and after 12 months. After 1 year, the nanofilled resin composite showed similar performance to the other packable and microhybrid resin composites.  相似文献   
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This report shows images of a case of subcutaneous phaeohyphomycosis caused by Exophiala jeanselmei in a patient who has undergone renal transplantation. The paper comments briefly on the disease and emphasizes the need to take this mycosis into account in the differential diagnosis of other dermatoses, including non-infectious dermatoses.  相似文献   
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Cytopathic effects related to the human papillomavirus (HPV) infection are more frequently found in cervical intraepithelial neoplasia (CIN) 1; however, there are indications that at least half the histological diagnoses of CIN2 and CIN3 include koilocytosis areas. The objective of this study was to evaluate the frequency of the cytological criteria suggestive of HPV infection in the cervical smears of women with a histological diagnosis of CIN. One hundred and sixty-two women with abnormal cervical smears and a diagnosis of CIN confirmed by histopathology were selected, including 46 cases of CIN 1, 42 of CIN 2 and 74 cases of CIN 3. Koilocytosis was found in 63% of the smears from women with a histopathological diagnosis of CIN 1. This sign was observed in 26.2% and 25.7% of smears of women with a diagnosis of CIN 2 and CIN 3, respectively. Cytomegaly also was frequent in cervical smears of women with histopathological diagnosis of CIN 1 (71.8%). On the other hand, spindle cells and atypical metaplasia were more frequent in women with CIN 2 and CIN 3. Atypical parakeratosis showed similar frequency in all grades of CIN diagnosis. Koilocytois and cytomegaly were inversely correlated with the diagnosis of CIN2 or CIN 3, with OR values respectively of 0.30 (95%CI 0.13-0.68) and 0.26 (95%CI 0.11-0.58). The others signs analyzed did not show any significant association. Koilocitosis and cytomegaly can provides good reassurance that a patient with atypical cervical smear have CIN 1.  相似文献   
80.
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