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101.
等温滴定微量热法(ITC)是近年来发展起来的一种研究生物分子相互作用的重要方法。在研究蛋白质与外源小分子的相互作用时,优化样品的预处理,通过将蛋白质进行3次透析、准确定量蛋白质实际浓度、调控pH值和使用第3次透析缓冲溶液作为溶剂,实现了"相对零背景"的反应系统。将未优化组和优化处理组样品所进行的ITC检测结果进行比较,表明进行样品预处理的优化对获得有效的检测结果十分必要。  相似文献   
102.
介绍了采用扩散渗析技术从铜冶炼废酸中回收硫酸的研究,与传统处理工艺相比,扩散渗析法能耗低、环境污染小,酸回收率达到90%以上,并能有效截留主要杂质。  相似文献   
103.
Peritoneal dialysis (PD) is an efficient renal replacement therapy for patients with end-stage renal disease. Even if it ensures an outcome equivalent to hemodialysis and a better quality of life, in the long-term, PD is associated with the development of peritoneal fibrosis and the consequents patient morbidity and PD technique failure. This unfavorable effect is mostly due to the bio-incompatibility of PD solution (mainly based on high glucose concentration). In the present review, we described the mechanisms and the signaling pathway that governs peritoneal fibrosis, epithelial to mesenchymal transition of mesothelial cells, and angiogenesis. Lastly, we summarize the present and future strategies for developing more biocompatible PD solutions.  相似文献   
104.
Outcome of acute renal failure (ARF) and use of continuous renal replacement therapy (CRRT) have shown a consistently high mortality. (1) Evaluate the short-term patient survival. (2) Evaluate dialysis-free survival. (3) Evaluate risk factors associated with overall survival and the continued need for intermittent dialysis. We identified adults (≥18 years) needing CRRT, treated in the critical care units of Froedtert Medical and Lutheran Hospital from January 1, 2003 till December 31, 2005. Patients were divided into two major groups needing CRRT, end stage renal disease (ESRD) (chronic dialysis) and non-ESRD with ARF. Continuous renal replacement therapy was performed with an average of 2 L replacement fluid exchanges/h. Sigma stat software was used for analysis. Comparison was done for noncontinuous variables by chi-square and t test for categorical and continuous variables, respectively. A total of 110 (ESRD 24/non-ESRD 86) patients received CRRT during study period. Over all in-hospital mortality among non-ESRD patients was 63% vs. 46% for ESRD. Among non-ESRD patients who survived, 47% needed intermittent hemodialysis on intensive care unit discharge and 28% continued to need hemodialysis at last follow-up. Among non-ESRD patients alive at discharge, those who were dialysis dependent on last follow-up were older (64.5) than those who did not require dialysis on last follow-up (58.4) P=0.347. Non-ESRD patients who died were in the hospital for an average of 17.5 days compared with 29 days for those who were discharged from the hospital. Patients with ARF needing CRRT have high in-hospital mortality. A significant percentage of patients remained dialysis dependant on last follow-up.  相似文献   
105.
Peritoneal dialysis (PD) represents the dialysis modality of choice for pediatric patients with end-stage kidney disease. Indeed, compared with hemodialysis (HD), it offers many advantages, including more flexibility, reduction of the risk of hospital-acquired infections, preservation of residual kidney function, and a better quality of life. However, despite these positive aspects, PD may be associated with several long-term complications that may impair both patient’s general health and PD adequacy. In this view, chronic inflammation, caused by different factors, has a detrimental impact on the structure and function of the peritoneal membrane, leading to sclerosis and consequent PD failure both in adults and children. Although several studies investigated the complex pathogenic pathways underlying peritoneal membrane alterations, these processes remain still to explore. Understanding these mechanisms may provide novel approaches to improve the clinical outcome of pediatric PD patients through the identification of subjects at high risk of complications and the implementation of personalized interventions. In this review, we discuss the main experimental and clinical experiences exploring the potentiality of the proteomic analysis of peritoneal fluids and extracellular vesicles as a source of novel biomarkers in pediatric peritoneal dialysis.  相似文献   
106.
Introduction: End‐stage renal disease (ESRD) is associated with perturbations in thyroid hormone concentrations and an increased prevalence of hypothyroidism. Few studies have examined the effects of hemodialysis dose or frequency on endogenous thyroid function. Methods: Within the Frequent Hemodialysis Network (FHN) trials, we examined the prevalence of hypothyroidism in patients with ESRD. Among those with endogenous thyroid function (without overt hyper/hypothyroidism or thyroid hormone supplementation), we examined the association of thyroid hormone concentration with multiple parameters of self‐reported health status, and physical and cognitive performance, and the effects of hemodialysis frequency on serum thyroid stimulating hormone (TSH), free thyroxine (FT4), and free tri‐iodothyronine (FT3) levels. Conventional thrice‐weekly hemodialysis was compared to in‐center (6 d/wk) hemodialysis (Daily Trial) and Nocturnal (6 nights/wk) home hemodialysis (Nocturnal Trial) over 12 months. Findings: Among 226 FHN Trial participants, the prevalence of hypothyroidism was 11% based on thyroid hormone treatment and/or serum TSH ≥8 mIU/mL. Among the remaining 195 participants (147 Daily, 48 Nocturnal) with endogenous thyroid function, TSH concentrations were modestly (directly) correlated with age (r = 0.16, P = 0.03) but not dialysis vintage. Circulating thyroid hormone levels were not associated with parameters of health status or physical and cognitive performance. Furthermore, frequent in‐center and nocturnal hemodialysis did not significantly change (baseline to month 12) TSH, FT4, or FT3 concentrations in patients with endogenous thyroid function. Discussion: Among patients receiving hemodialysis without overt hyper/hypothyroidism or thyroid hormone treatment, thyroid indices were not associated with multiple measures of health status and were not significantly altered with increased dialysis frequency.  相似文献   
107.
刘光明  任艳  李川  杨宁  唐常杰 《软件学报》2017,28(3):732-743
信息网络数据立方(InfoNetCube)的计算是进行信息网络在线分析处理的基础.然而,不同于传统的数据立方,信息网络数据立方由多个子方体格组成,每个方体格中的任意方体(cuboid)的任意单元格都包含一个主题图(或称图度量),因而空间开销较传统数据立方大2个数量级以上.如何快速、高效进行信息网络数据立方的部分物化是极具挑战的研究课题.本文提出基于“透析计算”思想的信息网络立方物化策略,通过主题图度量在信息维和拓扑维上反单调性运用,提出基于“透析计算”的空间剪枝算法,快速透析掉不可能命中的子图度量、方体单元、方体乃至方体格.实验结果表明,本文提出的基于“透析计算”的部分物化策略,可以对信息网络方体进行有效剪枝,算法较基于基本方体的部分物化策略运行时间平均降低75%.  相似文献   
108.
Arabinoxylans (AX) treated with protease and dialyzed (AXP) or only dialyzed (AXD) formed gels showing an increase in the elastic modulus G′ (1291 and 1419 Pa, respectively) and the ferulic acid dimers (3.34 and 3.10 μg/mg polysaccharide, respectively) and trimers (0.51 and 0.53 μg/mg polysaccharide, respectively) in comparison to AX gels (767 Pa, 0.56 and 0.12 μg/mg polysaccharide, respectively). Nevertheless, the G′ values and crosslinking contents were not different among the AXP and AXD gels, suggesting that the amount of protein removed (54%) does not affect these parameters. Confocal laser scanning microscopy analysis showed that AXP treatment promotes the homogeneity of the gels. In addition, scanning electron microscopy observations indicated that AXD and particularly AXP gels had a more compact microstructure. Thus, the partial removal of protein associated with AX does not impact the viscoelasticity and crosslinking content of the gels formed but could improve their microstructural characteristics. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47300.  相似文献   
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