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BackgroundLymphoma is the third most common pediatric malignancy. The purpose of this study was to analyze the incidence rates of lymphoma in children and adolescents in Brazil.MethodsAll cases of Hodgkin lymphoma (HL), non-Hodgkin lymphoma (NHL), and Burkitt lymphoma (BL) were extracted from 14 population-based cancer registries (PBCRs) from 2000 to 2005, and included children and adolescents 0–19 years old. Analyses included age-adjusted incidence rates (AAIRs) and age-specific incidence rates (ASIRs) by each PBCR. A social exclusion index (SEI) was built and used as proxy for socioeconomic status (SES) levels. Correlations between SES and incidence rates were investigated using Spearman's test.ResultsThe median incidence of lymphoma was 22.7/million. AAIRs of lymphomas varied from 12.9 (Salvador) to 34.5 per million (São Paulo). Median AAIR was 8.8/million, 9.8/million, and 2.9/million for NHL, HL, and BL, respectively. In all PBCRs except that of Recife, AAIR was slightly higher in males than females. The median ASIR was highest for HL (18.5/million) at 15–19 years for both genders. For NHL there were two peaks for ASIR: 11.1/million (1–4 years of age) and 13.2/million (15–19 years of age). The median ASIR for BL was highest among children aged 1–4 years (4.7/million) and in males. Higher SEI correlated with higher incidence of HL (P = 0.06), whereas rates of NHL and BL did not correlate with SEI. Borderline different incidence rates were observed in HL correlated with cities with higher SEIs.ConclusionIncidence rates of lymphomas in Brazil do not differ compared to rates reported worldwide, although SES differences deserve further investigation.  相似文献   
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BACKGROUND: Recurrence infection following successful eradication of Helicobacter pylori is usually low, except for countries with high prevalence of H. pylori. The aim of this study was to verify H. pylori recurrence rate in patients with duodenal ulcer after eradication and the possible relationship with environmental factors, histologic pattern of the mucosa and bacterial genotype. MATERIALS AND METHODS: One-hundred and ninety-four patients with an active duodenal ulcer and who were successfully treated for H. pylori infection from 1990 to 1999 were studied. A questionnaire was answered about their living conditions, and a 14C-urea breath test was performed. Patients with a positive breath test underwent an upper endoscopy to investigate for possible ulcer recurrence; gastric biopsy samples were than collected for rapid urease test and for histologic assessment. H. pylori vacA and cagA genotype was determined by polymerase chain reaction in those samples with positive urease test. RESULTS: H. pylori infection was detected in 11 patients (recurrence rate of 5.7%) that were not associated with the type of bacterial virulence. In 10 patients the ulcer was healed and all of them were clinically asymptomatic. In eight, histology showed an intensification of gastritis. All 11 patients had adequate housing and sanitary conditions and no other risk for H. pylori recurrence was identified. CONCLUSIONS: The recurrence rate of H. pylori in Brazil was higher than that reported in developed countries, but lower than usually reported in developing ones. Ulcer relapse rarely occurs even in long-term follow up.  相似文献   
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The hormonal oscillations that occur during the female reproductive cycle influence the morphophysiology of several organs of the reproductive system. The female prostate is a functional organ sensitive to the action of steroidal hormones, but it is not known whether the hormonal oscillations that occur during the reproductive cycle can alter the biology of this gland. Thus, the present work aims to evaluate the morphofunctional aspects of the female prostate during the gerbil estrous cycle. For this purpose, morphological, morphometric-stereological, serological, and immunocytochemical analyses were carried out. The results of the present study show that the hormonal oscillations that occurred during the estrous cycle altered both the structure and functionality of the gerbil female prostate. These alterations include increased prostatic growth and augmented secretory activity during the proestrus and estrus phases and a gradual decrease of the secretory activity and glandular development in the diestrus I and II phases. These cyclical oscillations appear to be determined by the hormonal peaks of estrogen in diestrus II and by the high levels of progesterone during estrus, since the androgen levels remained constant throughout the estrous cycle.  相似文献   
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The penises of bats are taxonomically distinctive in size and shape. In addition, they are variable in microscopic anatomy, indicating that histomorphological studies of copulatory organs of bats may help understanding their successful reproductive strategies. We studied adult males of 13 species of vespertilionid and phyllostomid bats. Both families exhibited the basic structure of the vascular penis of mammals: the hydrostatic elements of the corpora cavernosa and the corpus spongiosum surrounding the urethra, as well as accessory cavernous tissue. Variation in the position and amount of the tissues were observed in these families. Vespertilionid bats have a small glans penis with abundant accessory cavernous tissue on the prepuce and a highly variable baculum. The baculum varied in size and morphology, even among congeneric species, such as the three Lasiurus species and the two Myotis species. Phyllostomid species possess no bacula, but vascular structures are present to produce penile stiffening, particularly on the glans. Variation in the microscopic anatomy of the phyllostomid prepuce was observed, for example, Artibeus species had accessory cavernous tissue surrounded by a tunica albuginea, but Carollia perspicillata had two bundles of striated musculature and some adipose tissue; abundant pigments were present in the prepuce of most species.  相似文献   
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Mycopathologia - Systemic infections due to Candida tropicalis are conditions which can frequently lead to death. The aim of this report is to describe the features of C. tropicalis biofilm in a...  相似文献   
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The goal of treatment of chronic hepatitis C is to achieve a sustained virological response, which is defined as exhibiting undetectable hepatitis C virus (HCV) RNA levels in serum following therapy for at least six months. However, the current treatment is only effective in 50% of patients infected with HCV genotype 1, the most prevalent genotype in Brazil. Inhibitors of the serine protease non-structural protein 3 (NS3) have therefore been developed to improve the responses of HCV-infected patients. However, the emergence of drug-resistant variants has been the major obstacle to therapeutic success. The goal of this study was to evaluate the presence of resistance mutations and genetic polymorphisms in the NS3 genomic region of HCV from 37 patients infected with HCV genotype 1 had not been treated with protease inhibitors. Plasma viral RNA was used to amplify and sequence the HCV NS3 gene. The results indicate that the catalytic triad is conserved. A large number of substitutions were observed in codons 153, 40 and 91; the resistant variants T54A, T54S, V55A, R155K and A156T were also detected. This study shows that resistance mutations and genetic polymorphisms are present in the NS3 region of HCV in patients who have not been treated with protease inhibitors, data that are important in determining the efficiency of this new class of drugs in Brazil.  相似文献   
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