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491.
To test the hypothesis of vascular sequestration of parasitized erythrocytes in Plasmodium falciparum malaria in vivo, a pathologic and immunohistochemical study was done of the microvasculature of skeletal muscle biopsy samples from P. falciparum malaria patients at different stages of severity. Parasitized red blood cells sequestered in the skeletal muscle vessels were observed in samples from necropsies but were never demonstrated in biopsy specimens. Vascular cell adhesion molecule-1 and E-selectin expression was consistent only in specimens from cerebral malaria patients. Samples from such patients had strong staining of the constitutive endothelial adhesion molecules tested. The staining intensity gradually decreased in samples from persons with milder forms of the disease. Four of 13 patients with severe malaria had aggregates of red blood cells, occasionally parasitized inside the muscle fibers. These data suggest that skeletal muscle biopsy could be a useful model for the study of the pathogenesis of malaria in vivo.  相似文献   
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A critical aspect in the development of biomaterials is the optimization of their surface properties to achieve an adequate cell response. In the present work, electrospun polycaprolactone nanofiber meshes (NFMs) are treated by radio‐frequency (RF) plasma using different gases (Ar or O2), power (20 or 30 W), and exposure time (5 or 10 min). Morphological and roughness analysis show topographical changes on the plasma‐treated NFMs. X‐ray photoelectron spectroscopy (XPS) results indicate an increment of the oxygen‐containing groups, mainly ? OH and ? C?O, at the plasma‐treated surfaces. Accordingly, the glycerol contact angle results demonstrate a decrease in the hydrophobicity of plasma‐treated meshes, particularly in the O2‐treated ones. Three model cell lines (fibroblasts, chondrocytes, and osteoblasts) are used to study the effect of plasma treatments over the morphology, cell adhesion, and proliferation. A plasma treatment with O2 and one with Ar are found to be the most successful for all the studied cell types. The influence of hydrophilicity and roughness of those NFMs on their biological performance is discussed. Despite the often claimed morphological similarity of NFMs to natural extracellular matrixes, their surface properties contribute substantially to the cellular performance and therefore those should be optimized.  相似文献   
495.
Noncommunicable diseases (NCD) and age-associated diseases (AAD) are some of the gravest health concerns worldwide, accounting for up to 70% of total deaths globally. NCD and AAD, such as diabetes, obesity, cardiovascular disease, and cancer, are associated with low-grade chronic inflammation and poor dietary habits. Modulation of the inflammatory status through dietary components is a very appellative approach to fight these diseases and is supported by increasing evidence of natural and dietary components with strong anti-inflammatory activities. The consumption of bioactive lipids has a positive impact on preventing chronic inflammation and consequently NCD and AAD. Thus, new sources of bioactive lipids have been sought out. Microalgae are rich sources of bioactive lipids such as omega-6 and -3 polyunsaturated fatty acids (PUFA) and polar lipids with associated anti-inflammatory activity. PUFAs are enzymatically and non-enzymatically catalyzed to oxylipins and have a significant role in anti and pro-resolving inflammatory responses. Therefore, a large and rapidly growing body of research has been conducted in vivo and in vitro, investigating the potential anti-inflammatory activities of microalgae lipids. This review sought to summarize and critically analyze recent evidence of the anti-inflammatory potential of microalgae lipids and their possible use to prevent or mitigate chronic inflammation.  相似文献   
496.
This paper proposes a numerical solution for the diffusion equation with convective boundary condition applied to solids obtained through the revolution of arbitrary bi-dimensional geometries, using generalized coordinates. The diffusion equation was discretized using the finite volume method, with a fully implicit formulation. The solution exploits symmetry conditions and that decreases the computational effort demanded, in comparison to the traditional use of three-dimensional grids. The proposed solution was used to describe diffusion processes which have a well-known solution. There was a good agreement among the results obtained through the proposed solution and the correspondent analytical solutions, as well as the experimental data.  相似文献   
497.
In order to account for wide variation in the relationship between leader–member exchange and employees' affective organizational commitment, we propose a concept termed supervisor's organizational embodiment (SOE), which involves the extent to which employees identify their supervisor with the organization. With samples of 251 social service employees in the United States (Study 1) and 346 employees in multiple Portuguese organizations (Study 2), we found that as SOE increased, the association between leader–member exchange and affective organizational commitment became greater. This interaction carried through to in-role and extra-role performance. With regard to antecedents, we found in Study 1 that supervisor's self-reported identification with the organization increased supervisor's expression of positive statements about the organization, which in turn increased subordinates' SOE. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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In vitro studies of chlorpromazine (CPZ) a popular anti-psychotic drug has shown radiation sensitizing effects at higher celluar concentration and protective effect at a lower concentration. The present study was designed to evaluate both sensitizing and protective effects in the treatment of advanced cancer of the cervix treated with hypofractionated external radiation and intratumoural injection of chlopromazine. Twenty patients were treated with intratumoural CPZ and radiation, while, 23 patients received radiation alone. A 52.94% complete response was noted in CPZ arm while 39.1% complete response in the control. A trend towards improved response is seen in CPZ group. Similarly patients who received CPZ showed significantly low proctitis rates.  相似文献   
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A recent suggestion on the applicability of supercritical fluid extraction to the deacidification of olive oils of high acid content was based on solubility data in clear disagreement with the results of other authors. In this work, we measured the solubilities of substances chosen for their importance in that extraction process, namely pure glycerol trioleate, the most abundant triglyceride in olive oil, and of a husk oil with a high acid content. Our results agree well with some of the previous reports on this subject. These seem to be a trustworthy data base, but more results are needed for a definite conclusion about the technical feasibility of the process.  相似文献   
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