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The main reason why peritoneal dialysis (PD) still has limited use in the management of patients with end-stage renal disease (ESRD) lies in the fact that the currently used glucose-based PD solutions are not completely biocompatible and determine, over time, the degeneration of the peritoneal membrane (PM) and consequent loss of ultrafiltration (UF). Here we evaluated the biocompatibility of a novel formulation of dialytic solutions, in which a substantial amount of glucose is replaced by two osmometabolic agents, xylitol and l-carnitine. The effect of this novel formulation on cell viability, the integrity of the mesothelial barrier and secretion of pro-inflammatory cytokines was evaluated on human mesothelial cells grown on cell culture inserts and exposed to the PD solution only at the apical side, mimicking the condition of a PD dwell. The results were compared to those obtained after exposure to a panel of dialytic solutions commonly used in clinical practice. We report here compelling evidence that this novel formulation shows better performance in terms of higher cell viability, better preservation of the integrity of the mesothelial layer and reduced release of pro-inflammatory cytokines. This new formulation could represent a step forward towards obtaining PD solutions with high biocompatibility.  相似文献   
3.
On education     
The following observations are intended only to outline some concerns about, and to offer observations on, the teaching of design disciplines in the University of Buenos Aires and to rehearse the current educational challenges relating to achieving the standards expected of a professional graduate competent to improve our environmental demands.  相似文献   
4.
进行干粉灭火系统计算研究的主要目的是为干粉灭火系统的设计或设计规范的编写提供依据 ,以保证设计具有科学性、可靠性和可行性。基于这一宗旨 ,干粉灭火系统计算研究的内容主要包括确定系统中各个管段的管径、系统的工作压力和泄压口面积等。1 管道直径的确定管道直径的大小由管道中通过的气固两相流体的体积和适宜的流动速度决定 ,前者可依据管道中需要输送的干粉量、驱动气体的种类、驱动气体系数、环境温度和管道中的压力计算出来 ;而后者则需要通过试验确定。为使干粉灭火系统管道内干粉与驱动气体不分离 ,干粉 -驱动气体二相流必须…  相似文献   
5.
本文引入环境形象整体现,在环境结构原型分析的基础上结合实践探讨了住宅小区环境整体性设计,旨在强调设计的整体性及尝试设计方法上的新思路。  相似文献   
6.
The decomposition of ClO2 and ClO2 by u.v. radiation leads to the production of chlorate, chloride and oxygen as end-products via complex reactions which are initiated by the products generated by the primary reactions of photolysis (Buxton and Subhani, 1972a; Mialocq et al., 1973; Karpel Vel Leitner et al., 1992). As far as the rate of decomposition is concerned, Bowen and Cheung (1932) and Zika et al. (1985) have shown that the quantum yield of photodecomposition of chlorine dioxide (overall reaction) increases when the wavelength decreases [Zika et al. (1985): φ = 0.46 at 366 nm and 1.4 at 296.7 nm]. However, the values of the quantum yield of photodecomposition of ClO2 and ClO2 at 253.7 nm as well as the quantum yields for the primary reactions of photolysis of ClO2 and ClO2 at different wavelengths are not given in the literature.The aim of this work was to study the kinetics of photodecomposition of chlorine dioxide and of chlorite by u.v. irradiation.  相似文献   
7.
The human senses play an important role in assessing the quality of food and of the environment. Particularly the chemical senses of taste and smell determine the pleasantness of foods and drinks and may provide a warning mechanism for the presence of more or less toxic contaminants. Even after the recent rapid development of powerful analytical techniques the human nose can easily detect trace amounts of chemicals at levels manytimes lower than the analytical detection limits.Although taste and odour assessment of drinking water has been practized inmany waterworks laboratories by small panels, relatively unreliable results were obtained and such sensory data played up till now only a minor role in the management of the water treatment plant. More sophisticated and reliable methods for sensory water quality evaluation are discussed. Special attention is given to the characteristics of the human senses of taste and smell, to which the methodology of sensory assessment should be better adapted. High numbers of observations on a sample are generally needed, for which purpose the use of large panels has to be realized. In this respect the help of large consumer panels is an alternative for the presently often used small laboratory groups. As an example the preliminary results of a large ongoing experiment of sensory water quality assessment by 2 consumer panels of 100 persons each in the Rotterdam area are discussed. Drinking water quality is judged at the consumer homes every week. The experiment started September 1979 and will be continued for one year.  相似文献   
8.
一、休闲农业的兴起随着人民生活水平的提高及农业的发展,以种养业为主的自然经济型农业正在向集约化、规模化、深加工的产业经济型农业迅速发展。同时,随着世界人口城市化速度的加快,  相似文献   
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Bulletin of Engineering Geology and the Environment - La fermeture de l'Escaut oriental constitute le couronnement des travaux du Plan Delta aux Pays-Bas. Le danger de l'érosion et de...  相似文献   
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