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The aim of this study was to analyze maternal mortality in Brazil in the last 30 years, by means of a literature review. The authors performed an electronic search of scientific articles from 1980 to 2010 in LILACS and MEDLINE and found 486 abstracts, of which 50 articles were selected. Studies showed a decrease in the maternal mortality ratio (MMR), although varying across regions of the country. A few articles evaluated maternal mortality factors, identifying social inequalities associated with skin color and schooling. There was persistent underreporting of maternal deaths and inadequate completion of death certificates. Direct obstetric causes were the most frequent, mainly hypertensive diseases of pregnancy. Analysis of avoidability revealed deficiencies in prenatal and childbirth care. Despite the relevance of maternal mortality in Brazil, there are few studies on the subject. Although MMR has decreased, it is still above the desired levels. Improvements are thus needed in the quality of prenatal and perinatal care.  相似文献   
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The phase behavior of EPR/hexane mixtures over the whole range of composition has been investigated by means of DSC. When the hexane content is lower than 37%, vitrification of the mixture hinders solvent crystallization and the composition dependence of the glass transition temperature (Tg) is well described by the Gordon-Taylor equation. At higher diluent concentration, Tg is sufficiently lowered to allow crystallization and all hexane in excess with respect to 37% separates from the mixture. Calorimetric curves also reveal the presence of a small amount of low-melting crystallinity due to EPR component, strictly dependent on polymer concentration. The conclusion is drawn that the increase of mobility induced by plasticization does not enhance the crystallization capability of EPR macromolecules.  相似文献   
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The prognostic significance of macrophage and natural killer (NK) cell infiltration in colorectal carcinoma (CRC) microenvironment is unclear. We investigated the CRC innate inflammatory infiltrate in over 1,600 CRC using two independent tissue microarrays and immunohistochemistry. Survival time was assessed using the Kaplan–Meier method and Cox proportional hazards regression analysis in a multivariable setting. Spearman's rank correlation tested the association between macrophage and lymphocyte infiltration. The Basel study included over 1,400 CRCs. The level of CD16+ cell infiltration correlated with that of CD3+ and CD8+ lymphocytes but not with NK cell infiltration. Patients with high CD16+ cell infiltration (score 2) survived longer than patients with low (score 1) infiltration (p = 0.008), while no survival difference between patients with score 1 or 2 for CD56+ (p = 0.264) or CD57+ cell (p = 0.583) infiltration was detected. CD16+ infiltrate was associated with improved survival even after adjusting for known prognostic factors including pT, pN, grade, vascular invasion, tumor growth and age [(p = 0.001: HR (95% CI) = 0.71 (0.6–0.9)]. These effects were independent from CD8+ lymphocyte infiltration [(p = 0.036: HR (95% CI) = 0.81 (0.7–0.9)] and presence of metastases [(p = 0.002: HR (95% CI) = 0.43 (0.3–0.7)]. Phenotypic studies identified CD16+ as CD45+CD33+CD11b+CD11c+ but CD64? HLA‐DR‐myeloid cells. Beneficial effects of CD16+ cell infiltration were independently validated by a study carried out at the University of Athens confirming that patients with CD16 score 2 survived longer than patients with score 1 CRCs (p = 0.011). Thus, CD16+ cell infiltration represents a novel favorable prognostic factor in CRC.  相似文献   
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Introduction

The aim of this study was to determine in anterior teeth, bicuspids, and molars (1) the accuracy of 3 different electronic apex locators (EALs) in detecting the apical foramen and (2) the accuracy of digital radiography in determining the working length (WL), compared with visible control under a microscope.

Methods

By using radiovideography (RVG), we measured the lengths of 120 root canals with 3 different EALs (Endex, ProPex II, and Root ZX) and compared them with the actual lengths. The accuracy of EALs and RVG was related to each dental category. An endodontic training kit (Pro-Train) was used during experimental procedures.

Results

Statistical analysis showed that the 3 EALs and RVG were less accurate in anterior teeth and molars than in bicuspids. The paired-sample t test showed no statistically significant difference between mesiodistal plane and buccolingual plane digital radiography in all groups.

Conclusions

The 3 EALs tested were more accurate in detecting the apical foramen in bicuspids than in both molars and anterior teeth. Radiographic measurements were not reliable for determining WL in all dental groups in both radiographic planes.  相似文献   
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