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Annals of Surgical Oncology - Although pathological complete response (pCR) after multimodal treatment for esophageal cancer is associated to the best prognosis, recurrence may occur in...  相似文献   
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Although adolescents living on the street tend to have unprotected sex with many partners and substance abuse, little is known about this reality in Brazil. To estimate the prevalence and factors associated with risky sexual behavior among children and adolescents living on the street in Porto Alegre and Rio Grande. A cross-sectional study was carried out using the Respondent-Driven Sampling (RDS) sampling method to quickly and efficiently access populations of difficult access. Poisson regression with robust adjustment of variance was used in the multivariate analysis. The sample consisted of 231 participants aged 10–21 years. Most were male and aged 16- 21 years. More than half (66.7%) of the respondents did not have a school bond, and 64.5% did not live with the family. Half of the sample had been living on the street for at least four years, spending 15 h or more on the street. Most (86.6%) responded that they had already used illicit drugs in their lives, and unprotected sex prevalence was 61.9%. The variables independently associated with unprotected sex were years living on the street, hours spent on the street, having a steady partner, illicit drug use, and sexual intercourse without a condom under the influence of drugs. The high prevalence of unprotected sex points to the need for intervention policies for this population to prevent the main risk factors.

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Receptors for IgM were detected on peripheral blood human eosinophils by a rosette technique with ox red blood cells coated with the IgM fraction of the specific immunserum. Between 14 % and 43 % (mean 27 %) FcµR positive cells were found after an overnight incubation period at 37°C by using this technique. The specificity of the receptors for IgM was assessed by studying the inhibitory capacity of purified human IgM in the rosette assay. From an ultrastructural point of view, the EAM rosette-forming cells are mature eosinophlic granulocytes characterized by a nucleus with a variable number of lobes and a certain number of «first type» granules partially or totally devoid of their content.  相似文献   
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A double-blind, placebo-controlled study was carried out to assess the effects of a three-month treatment with a new ACE inhibitor, Benazepril (BNZ), on systemic and renal hemodynamics, and urine protein excretion, in 20 patients with chronic glomerulonephritis, normal blood pressure (130/83 +/- 16/10 mm Hg), and normal renal function (creatine clearance 106 +/- 25 ml/min). Treatments with placebo or BNZ were assigned randomly. A wide range of proteinuria lowering effect was observed in overall population (from 1 to 84%, average 34%). Following the arbitrary level of a 30% reduction, two well-matched subgroups (10 patients for each one) were obtained: "good responders" (average decrease 51%), and "poor responders" (average decrease 17%). The main distinctive feature between the two groups was a higher plasma renin activity level in good than in poor responders. A positive correlation between the fall in proteinuria and blood pressure was found. Although the decrease in blood pressure seems to represent the major factor in determining the reduction in proteinuria, a multiple correlation analysis showed that the most prominent role (71%) was attributable to the combined decrease in blood pressure and filtration fraction, and then also to the efferent arteriole dilatation. Our conclusion is that ACE inhibitors are capable of also reducing proteinuria in patients with renal disease with normal blood pressure, the effect being more pronounced in those exhibiting humoral, systemic and renal hemodynamic patterns, indicating a greater activity of circulating and renal renin angiotensin system.  相似文献   
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