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41.
The increasing use of products derived from nanotechnology has raised concerns about their potential toxicity, especially at the immunocompetence level in organisms. This study compared the immunotoxicity of cadmium sulfate/cadmium telluride (CdS/Cd‐Te) mixture quantum dots (QDs) and their dissolved components, cadmium chloride (CdCl2)/sodium telluride (NaTeO3) salts, and a CdCl2/NaTeO3 mixture on four animal models commonly used in risk assessment studies: one bivalve (Mytilus edulis), one fish (Oncorhynchus mykiss), and two mammals (mice and humans). Our results of viability and phagocytosis biomarkers revealed that QDs were more toxic than dissolved metals for blue mussels. For other species, dissolved metals (Cd, Te, and Cd‐Te mixture) were more toxic than the nanoparticles (NPs). The most sensitive species toward QDs, according to innate immune cells, was humans (inhibitory concentration [IC50] = 217 μg/mL). However, for adaptative immunity, lymphoblastic transformation in mice was decreased for small QD concentrations (EC50 = 4 μg/mL), and was more sensitive than other model species tested. Discriminant function analysis revealed that blue mussel hemocytes were able to discriminate the toxicity of QDs, Cd, Te, and Cd‐Te mixture (Partial Wilk's λ = 0.021 and p < 0.0001). For rainbow trout and human cells, the immunotoxic effects of QDs were similar to those obtained with the dissolved fraction of Cd and Te mixture. For mice, the toxicity of QDs markedly differed from those observed with Cd, Te, and dissolved Cd‐Te mixture. The results also suggest that aquatic species responded more differently than vertebrates to these compounds. The results lead to the recommendation that mussels and mice were most able to discriminate the effects of Cd‐based NPs from the effects of dissolved Cd and Te at the immunocompetence level. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 9–25, 2015.  相似文献   
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In an effort to make intensive lifestyle modification programs more accessible to patients with cardiovascular disease, the Ornish Program was offered at eight independent medical centers located across the United States. The purpose of this study was to determine if one of these independent sites was able to replicate outcomes produced by the original Ornish Program. Fifty program participants from six different cohorts provided baseline, 3- and 12-month data consisting of blood lipids, body fat, blood pressure, anginal pain, quality of life, stress, depression, social support, and hostility. A pooled analysis showed significant reductions in almost all physiological and psychosocial variables with most reductions persisting for at least 12 months. These findings suggest that cardiovascular disease patients who choose to participate in an independent, intensive lifestyle modification program can experience significant improvements in both physiological and psychosocial cardiovascular disease risk factors.  相似文献   
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Paraganglioma in pregnancy is an exceedingly rare and potentially life‐threatening diagnosis. It is important that the clinicians consider secondary causes when women present with hypertension in early pregnancy.  相似文献   
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After 30 years of hematopoietic stem cell use for various indications, umbilical cord blood is considered as an established source of cells with marrow and postmobilization peripheral blood. The limited number of cells still remains a problematic element restricting their use, especially in adults who require to be grafted with a higher cell number. Improving the quality of harvested cord blood, at least in terms of volume and amount of cells, is essential to decrease the number of discarded units. In this review, we examine several variables related to parturient, pregnancy, labor, delivery, collection, the newborn, umbilical cord, and placenta. We aim to understand the biologic mechanisms that can impact cord blood quality. This knowledge will ultimately allow targeting donors, which could provide a rich graft and improve the efficiency of the collection.  相似文献   
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AIDS and Behavior - We previously demonstrated that village community mobilization (CM) was associated with reduced HIV incidence among adolescent girls and young women (AGYW) in South Africa....  相似文献   
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AIDS and Behavior - Adolescents and young adults (AYA; 13–24&nbsp;years-old) comprise 22% of new HIV infections in the United States (US), most of whom live in the South. We used the...  相似文献   
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The overall objective of this study was to analyze the effects of a combined prenatal and postnatal (entire gestational human chronic drinking model) ethanol exposure on T-cell development in mice. Specifically, this study evaluated the effects of chronic exposure to prenatal ethanol on lymphocyte makeup and proliferative capabilities of postnatal offspring's (4 and 12 weeks) peripheral lymphoid tissues. Chronic exposure regimens were conducted over the entire gestational period and through postnatal day 14 or 21. Thymus, spleen, and intestinal intraepithelial lymphocytes were harvested and analyzed by flow cytometry for percentages of T-cell subsets. Splenic lymphocytes were also analyzed for their ability to proliferate in response to a T-cell mitogen. Limited effects of chronic ethanol exposure were seen.  相似文献   
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