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931.
Numerous lines of evidence implicate a role of myeloperoxidase (MPO) in the pathogenesis of cardiovascular disease (CVD). It is a well accepted fact that patients with chronic kidney disease (CKD) are at an increased risk for CVD. MPO is a pro-oxidant enzyme which could be involved in the increased susceptibility of these patients to CVD. Hence, the levels of plasma MPO was determined in healthy controls as well as in patients with CKD [stratified with the level of their kidney failure as CKD stages II–V (end stage renal disease)]. Plasma MPO was assayed by a spectrophotometric method. Serum urea and creatinine were estimated on a clinical chemistry analyzer using standard laboratory procedures. The mean plasma MPO levels were significantly lower with advancing stages of renal failure (P < 0.001). There was a positive correlation between MPO and GFR (r = +0.89, P < 0.001) and a negative correlation with urea (r = −0.85, P < 0.001) and creatinine (r = −0.82, P < 0.001). While an inverse association was observed between plasma MPO and urea in CKD patients, such an association was not observed in control subjects (P = 0.43). In conclusion, the decline in plasma MPO levels may be due to the inhibitory effect of uraemic toxins on the enzyme.  相似文献   
932.
We report a case of a diabetic, heterozygote with near normal hematology, marginally low level of hemoglobin A2(HbA2) having an increased level of hemoglobin F(HbF) that was pancellularly distributed among the red cells. BioRad DiaSTAT measurements gave a high glycated hemoglobin A1c(HbA1c) of 31.5% and the BioRad Variant analyzer recorded an HbA1c value which was very low, in discordance with the detected blood glucose levels. Flow cytometry and polymerization chain reaction (PCR) based studies were carried out which revealed the case to be that of the common hereditary persistence of fetal hemoglobin (HPFH)-3, an Asian Indian mutation. Fructosamine estimation and HbA1c by Boronate affinity chromatography were able to resolve the discordant value detected and was able to confirm the diabetes status. The case would have been a diagnostic dilemma, if reported without correlation.  相似文献   
933.
基于AHP的旅游搜索引擎评价分析   总被引:1,自引:0,他引:1  
在简要介绍旅游搜索引擎基本概念和特点的基础上,运用层次分析法建立以流量速度指标、检索范围及功能指标、服务功能指标为一级指标,下设15个二级指标的旅游搜索引擎评价指标体系,探讨合理分配指标权重的方法,指出各指标的数据来源,并用于对目前国内主要旅游搜索引擎的分析,从而得到旅游搜索引擎的发展现状和现今所存在的问题。  相似文献   
934.
张维朋 《科技通报》2011,27(4):479-483
研究女性胆固醇随年龄变化的趋势.采集大最女性胆固醇数据,以10岁为年龄段,计算每个年龄段健康女性胆固醇平均值,并以女性70岁以下6个年龄段的胆固醇为原始数列,建立了女性胆固醇随年龄变化的灰色系统(GM(1,1))模型预测.后验差检验合格,预测70~79岁、80以上年龄段的女性胆固醇.预测分析结果表明,灰色系统GM(1,...  相似文献   
935.
数字电视整体转换给广电运营商带来前所未有的历史机遇,"三网融合"政策为广电综合业务的开展拓展了更宽阔的途径。通过技术和政策的推动,广电运营商彻底改变了以往业务单一、经营粗放的困境。运营支撑系统由于其自身的灵活性和可扩展性,作为广电整体转换后,所有业务统一接入和管理的综合平台,在广电实际运营过程中扮演着越来越重要的角色。本文通过介绍现代广电运营支撑系统的基础"eTOM模型"和一个实际建设的案例,说明在实际运营中,系统所起到的重要作用。  相似文献   
936.
翻译与二语习得关系的研究普遍受到我国外语教师及学者们的关注,基于不同角度的研究给我们呈现了这一课题的潜在研究价值。本文拟从建构主义生成学习理论视角,分析翻译在二语习得中的作用:为学习者通过翻译更好地习得二语提供理论支撑。也为该课题的研究展示一个新的切入点.  相似文献   
937.
The aim of this paper is to present a reliability modeling and analysis of a two-unit system of a continuous casting (CC) plant. Real maintenance data of a steel production plant have been used for the purpose. Three types of failures were noted: repairable, replaceable and reconditioning/reinstallation. The two-unit system is operating in parallel, on full-reduced installed capacity. Upon the unit failure, an inspection is carried out to decide the type of maintenance task to be performed. Optimized reliability indices of the plant such as mean time to system failure, availability, expected busy periods of the repairman for various maintenance tasks, expected number of visits by the repairman, expected number of repairs, replacements and reconditioning/reinstallation are obtained. Semi-Markov processes and regenerative point techniques are used for the analysis. Profit incurred to the CC plant is also evaluated and related graphs are plotted to demonstrate the results.  相似文献   
938.
Enterprise Information Portals (EIPs) have been widely adopted as platforms for the integration of knowledge management and information technology (IT). This study has been conducted from the knowledge management perspective in order to examine the influence of EIPs on collaborative commerce in the automobile industry. This study explores the integration of internal and external business processes and the coordination of collaborative design teams. An initial qualitative investigation explores the practical applications of an EIP in an automobile company. A research model is then formulated and tested using a questionnaire survey of the R&D department of a motor company in Taiwan. The results of the data analysis reveal that presence of EIPs can help a company realize the benefits of c-commerce. EIPs also can improve collaborative commerce performance by promoting the degree of integration of the enterprise process and by strengthening the process innovation and communication of collaborative design teams. The results suggest that managers should reinforce important factors, including knowledge management tools, process integration, and the quality of design teams, in order to achieve success in collaborative commerce.  相似文献   
939.
Customer relationship management (CRM) and knowledge management (KM) have become key strategic tool for all companies, especially in the current competitive environment. Moreover, customer knowledge is an important issue for CRM implementation. Reviewing the literature, we found many studies that analyze the crucial role played by KM initiatives as determinants of the success of CRM. Moreover, we found also diverse studies that show high rates of failure when implementing that strategy, so there is still no integrated conceptual framework to guide companies to their successful implementation. In this paper, with data of 153 Spanish hotels, we examine the relationships between KM and CRM success using a structural equation model. The main contribution is that having knowledge management capabilities is not sufficient for the success of CRM, but there are other factors to consider. In particular, organizational factors indeed impact CRM success and they appear to be intermediaries of the impact of other factors (KM capabilities/technological/customer orientation factors) in the success of CRM (in financial and marketing terms).  相似文献   
940.
简单介绍了射频识别的基本原理,特别是在室内定位中的应用。重点介绍了LANDMARC室内定位系统理论及其改进,使其可以更好地应用于实际环境。实验结果表明,改进的算法比原来的算法在定位精度上提高了10%~30%。  相似文献   
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