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Hemodialysis catheter (HDC) dysfunction due to thrombosis is common, and dysfunction incidence can reach up to 50% within 1 year of use. Although administration of intraluminal alteplase (tissue plasminogen activator [tPA]) is the standard of practice to pharmacologically restore HDC function, there are no evidence‐based guidelines concerning the optimal tPA dose. The purpose of this study was to compare the efficacy of 1.0‐mg vs. 2.0‐mg tPA dwell protocols in restoring the HDC function in thrombotic dysfunctional catheters. A retrospective, single‐center study was conducted on two independent cohorts of patients; the first (n = 129) received 2.0 mg tPA/catheter lumen, while the second (n = 108) received 1.0 mg tPA/catheter lumen. Kaplan–Meier and Cox regression analyses were performed to compare the catheter survival time between patients who received 1.0 mg tPA and those who received 2.0 mg tPA. Catheter removal occurred in 25 (19.4%) of those catheters treated with 1.0 mg tPA compared with 11 (10.2%) of catheters treated with 2.0 mg tPA (P = 0.05). The hazard ratio (HR) for catheter removal was 2.75 (95% confidence interval [95%CI] = 1.25–6.04) for the 1.0‐mg tPA cohort compared with the 2.0‐mg tPA cohort. Correction added on 3 December 2012, after first online publication: The tPA cohort values were changed. Female gender (HR = 2.51; 95%CI = 1.20–5.27) and age (HR = 0.96; 95%CI = 0.94–0.98) were also associated with catheter survival. Our findings suggest that treatment of dysfunctional HDC with 2.0‐mg tPA dwells is superior to 1.0‐mg tPA dwells.  相似文献   
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Wireless Personal Communications - The performance of wireless communication network is important in emergency rescue operations while ensuring optimum usage of limited wireless resources. Due to...  相似文献   
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A new method to grow single crystals with stoichiometry close to 1:1:2 of CuInTe2, an important member of the Cu-III-VI2 family of semiconductors is described. This consists of tellurization in the liquid phase of stoichiometric Cu and In and later solidification under directional freezing. It is found from energy dispersive spectroscopy that the ingots obtained with the evaporation temperature (Tt) of Te at 590 and 635°C were very close to the ideal stoichiometry 1:1:2. Samples of all ingots obtained with Tt between 530 and 690°C, as studied by x-ray and differential thermal analysis, were of single phase having chalcopyrite structure and p-type conductivity. Optical and electrical characterization of different ingots were made. The acceptor ionization energy EA and the density of states effective mass m p * of the holes are estimated from the temperature dependence of the hole concentration p in samples of different ingots. m p * = (0.78 ± 0.02) me agrees quite well with the reported value. From a combined analysis of the variation of EA with p1/3 and the knowledge of molecularity and valence stoichiometry of each sample, it is established that the shallow acceptor level observed in different samples with EA (0) ⋍ 30 meV is due to VIn.  相似文献   
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Sodium nitrite (SNT) widely used as a curative agent in meat processing industry possesses cell-transforming mutagenic and cytogenic properties. Dietary omega-3 polyunsaturated fatty acids (ω-3 PUFA) has been shown to reduce the severity of certain types of cancers, cardiovascular and renal diseases. The present study examined whether feeding of fish oil (FO)/flaxseed oil (FXO) has protective effect against SNT-induced toxicity. SNT significantly altered the activities of serum creatinine (Crt), blood urea nitrogen (BUN), metabolic and brush border membrane (BBM) enzymes. SNT caused significant imbalances in the antioxidant system associated with increased lipid peroxidation (LPO). Feeding of FO and FXO with SNT ameliorated the changes in various parameters caused by SNT. Nephrotoxicity parameters lowered and enzyme activities of carbohydrate metabolism, BBM and radioactively labeled inorganic phosphate (32Pi) transport were improved to near control values. The results of the present study suggest that ω-3 PUFA-enriched FO and FXO from sea-foods and plant sources respectively are similarly effective in reducing SNT-induced nephrotoxicity and oxidative damage.  相似文献   
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UV-vis absorption spectra and cyclic voltammograms of a selection of substituted thiophenes and their oligomers carrying trifluoracetyl acetone functional groups have been obtained. A comparison with calculated values of HOMO-LUMO energies (the former corresponding to the ionization potentials Ei) shows strong correlations between calculated and experimentally obtained data; they are in close agreement with estimates in terms of electron-donating and -withdrawing effects from an empirical point of view.  相似文献   
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In this work, shape optimization of a wire-wrapped fuel assembly in a liquid metal reactor has been carried out by combining a three-dimensional Reynolds-averaged Navier–Stokes analysis with the Kriging method, a well-known metamodeling technique for optimization. Sequential quadratic programming (SQP) is used to search the optimal point from the constructed metamodel. Two geometric design variables are selected for the optimization and design space is sampled using Latin Hypercube Sampling (LHS). The optimization problem has been defined as a maximization of the objective function, which is as a linear combination of heat transfer and friction loss related terms with a weighing factor. The objective function value is more sensitive to the ratio of the wire spacer diameter to the fuel rod diameter than to the ratio of the wire wrap pitch to the fuel rod diameter. The optimal values of the design variables are obtained by varying the weighting factor.  相似文献   
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有源滤波电路设计总结   总被引:1,自引:0,他引:1  
滤波器是一种能使有用信号通过而大幅抑制无用信号的电子装置。在电子电路中常用来进行信号处理、数据传输和抑制噪声等。在运算放大器广泛应用以前滤波电路主要采用无源电子元件--电阻、电容、电感连接而成,由于电感体积大而且笨重导致整个滤波器功能模块体积大而且笨重。本文介绍由集成运算放大器、电阻和电容设计有源滤波器,着重讲解低通、高通、带通滤波电路。  相似文献   
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