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41.
目的:探讨腹膜透析(PD)和血液透析(HD)对终末期肾脏疾病(ESRD)患者钙磷代谢及微炎症状态的影响。方法:选择2016年1月~2017年2月我院收治的ESRD患者94例为研究对象,采用随机数字表法分为PD组(47例)和HD组(47例),PD组给予非卧床持续性PD治疗,HD组给予HD治疗,治疗6个月后比较两组血清钙磷代谢水平和微炎症状态,并统计两组并发症的发生率。结果:治疗6个月后,两组血清钙水平与治疗前相比显著升高,血清磷水平显著降低(P0.05),但HD组与PD组比较无差异(P0.05);治疗6个月后,两组血清C-反应蛋白(CRP)水平较治疗前明显升高,且HD组高于PD组,差异有统计学意义(P0.05),治疗6个月后,两组降钙素原(PCT)水平与治疗前相比显著降低,差异有统计学意义(P0.05),但HD组与PD组比较无差异(P0.05);PD组感染、低蛋白血症的发生率高于HD组,HD组高血压、心律失常、充血性心衰的发生率高于PD组,差异均有统计学意义(P0.05)。结论:PD和HD治疗均可改善ESRD患者钙磷代谢紊乱,但两者都将加剧患者微炎症反应,其中HD对患者微炎症状态的影响更大。  相似文献   
42.
目的 调查腹膜透析患者相关感染情况,探讨护理对策以降低腹膜透析患者相关感染的发生率。方法 选取2010年5月至2014年8月宁波市鄞州区第二医院收治腹膜透析患者165例,观察腹膜透析患者相关性感染的发生、感染致病菌的分布以及透析护理中发病情况,分析腹膜透析患者相关感染发生的原因。结果 165例腹膜透析患者共有79例发生108次相关感染,其中腹膜炎32例共41次,出口感染17例共28次,出口处合并隧道感染28例共37次,隧道感染2例共2次;79例感染患者共有58例细菌培养为阳性,阳性率为73.42%。分离出病原菌63株,其中革兰阳性菌40株(占63.49%),革兰阴性菌19株(占30.16%),真菌4株(占6.35%);108次腹膜透析相关感染发生的原因:操作因素共67次,患者因素36次,环境因素3次,原因不明2次。结论 腹膜透析患者相关感染的致病菌主要为革兰阳性菌和革兰阴性菌,接触性感染和患者身体因素是腹膜透析患者相关感染的重要原因,采用恰当的护理对策能够有效降低感染发生率,有利于患者生活质量的提高。  相似文献   
43.
The effect of K+, Mg2+ and serotonin on the interaction between Ca2+ and different phospholipids as well as glycosphingolipids (gangliosides) was studied by equilibrium dialysis using 45Ca as tracer. The highly polar phosphatidylinositol-4,5-bisphosphate (TPI) was found to bind more Ca2+ per lipid molecule than all other lipids tested and Ca2+ could not be released as easily as in the other lipids by K+, Mg2+ and serotonin. Ca2+ is released from all lipid-Ca2+ complexes most effectively by Mg2+, serotonin is less effective but enhances K+ in its capacity to displace Ca2+ from the respective binding sites. A remarkable dissociating influence of serotonin on ganglioside-Ca2+ and phosphatidylserine-Ca2+ complexes is observed. This effect is less pronounced with phosphatidylinositol-Ca2+ complexes under comparable comparable conditions. The possible functional role of phospholipids and gangliosides in vivo is discussed with regard to the specific Ca2+-binding properties of these lipids.  相似文献   
44.
Beta-2 microglobulin (β2m) is the light chain of class I major histocompatibility complex (MHC-I). β2m is an intrinsically amyloidogenic protein that can assemble into amyloid fibrils in a concentration dependent manner. β2m is accumulated in serum of haemodialysed patients, and deposited in the skeletal joints, causing dialysis related amyloidosis. Recent reports suggested that the loop comprised between β2m strands D and E is crucial for protein stability and for β2m propensity to aggregate as cross-β structured fibrils. In particular, the role of Trp60 for β2m stability has been highlighted by showing that the Trp60 → Gly β2m mutant is more thermo-stable and less prone to aggregation than the wild type protein. On the contrary the Asp59 → Pro β2m mutant shows lower Tm and stronger tendency to fibril aggregation. To further analyse such properties, the Trp60 → Val β2m mutant has been expressed and purified; the propensity to fibrillar aggregation and the folding stability have been assessed, and the X-ray crystal structure determined to 1.8 Å resolution. The W60V mutant structural features are discussed, focusing on the roles of the DE loop and of residue 60 in relation to β2m structure and its amyloid aggregation trends.  相似文献   
45.
Cell‐free expression has become a highly promising tool for the efficient production of membrane proteins. In this study, we used a dialysis‐based Escherichia coli cell‐free system for the production of a membrane protein actively integrated into liposomes. The membrane protein was the light‐driven proton pump bacteriorhodopsin, consisting of seven transmembrane α‐helices. The cell‐free expression system in the dialysis mode was supplemented with a combination of a detergent and a natural lipid, phosphatidylcholine from egg yolk, in only the reaction mixture. By examining a variety of detergents, we found that the combination of a steroid detergent (digitonin, cholate, or CHAPS) and egg phosphatidylcholine yielded a large amount (0.3–0.7 mg/mL reaction mixture) of the fully functional bacteriorhodopsin. We also analyzed the process of functional expression in our system. The synthesized polypeptide was well protected from aggregation by the detergent‐lipid mixed micelles and/or lipid disks, and was integrated into liposomes upon detergent removal by dialysis. This approach might be useful for the high yield production of functional membrane proteins.  相似文献   
46.
Aims: The aim of this study was to identify and determine the diversity, occurrence and distribution of fungi in water used at a haemodialysis centre. Methods and Results: Samples in the hydraulic circuit for the distribution of the water, dialysate samples and samples of sterilization solution from dialysers were collected over a 3‐month period, and 500 ml of each sample was filtered through membranes. All together 116 isolates of fungi were recovered from 89% of all water samples collected inside the haemodialysis unit, with prevalence of moulds in tap water samples and of yeasts in dialysate samples. Fusarium spp. was the most abundant genus found, whereas Candida parapsilosis was the predominant yeast species. Conclusions: This study demonstrated that various fungi were present in the water system. These data suggest the inclusion of the detection and quantification of fungi in the water of haemodialysis. Significance and Impact of the Study: The recovery of fungi from aqueous haemodialysis environments implies a potential risk for haemodialysis patients and indicates the need for continuous maintenance and monitoring. Further studies on fungi in haemodialysis water systems are required to investigate the organism ability to persist, their role in biofilm formation and their clinical significance.  相似文献   
47.
3-((±)-2-Carboxypiperazin-4-yl)propyl-1-phosphonic acid (CPP) is an antagonist at the N-methyl-D-aspartate (NMDA) subtype of glutamate receptor. In the present study, levels of dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and 5-hydroxyindolacetic acid (5-HIAA) were measured after intracerebroventricular injection of NMDA, CPP or both in rat striatum using a brain dialysis method. The injection of NMDA produced a significant increase in DOPAC level. HVA level was also increased by NMDA injection. The level of 5-HIAA was not affected by NMDA injection. The injection of CPP had no effect on DOPAC, HVA and 5-HIAA levels. The injection of CPP restrained the increase of DOPAC and HVA levels induced by NMDA injection. The results suggest that intracerebral injection of NMDA may increase dopamine release from rat striatum, but have no effect on serotonin release. Furthermore, CPP inhibits NMDA induced release of dopamine.  相似文献   
48.
The availabilities of single-stranded 5S rRNA regions c, d and d' for base pairing interactions were analyzed by using synthetic DNA oligomers. Hybrid formation was detected by the endonucleolytical mode of the RNA-DNA specific action of RNase H. Provided that the hybrid interaction involved 6 successive base pairs, 5S rRNA loop c nucleotides 42-47 displayed accessibility in Escherichia coli, Bacillus stearothermophilus and Thermus thermophilus 5S rRNAs as well as in eukaryotic 5S rRNAs from Saccharomyces carlsbergensis, Rattus rattus and Equisetum arvense. Investigating eubacterial 5S rRNA regions d and d' (nucleotides 71-76 and 99-105, respectively), susceptibility was observed in E. coli 5S rRNA which, however, decreases in B. stearothermophilus and even more so in T. thermophilus 5S rRNA. For additional evaluation of the data obtained by RNase H cleavage, association constants of the hexanucleotides were determined by equilibrium dialysis at 4 degrees C for B. stearothermophilus 5S rRNA. The results obtained reveal that nucleotides 36-41 of B. stearothermophilus 5S rRNA are inaccessible for Watson-Crick interaction, which suggests that this part of loop c is in a structurally constrained configuration, or buried in the tertiary structure or involved in tertiary interactions.  相似文献   
49.
Abstract: The effects of chronic treatment with the specific, mechanism-based, irreversible inhibitors of 4-aminobutyrate aminotransferase (EC 2.6.1.19; GABA transaminase), ethanolamine O -sulphate (EOS), and 4-aminohexenoate [vigabatrin; γ-vinyl-GABA (GVG)] on the extracellular concentrations of GABA in the hippocampus have been studied using in vivo microdialysis in conscious animals. Oral dosing [3 mg/ml of drinking water, giving doses of GVG of 194 ± 38 mg/kg/day and of EOS of 303 ± 42 mg/kg/day (mean ± SD)] was followed by microdialysis at 2, 8, and 21 days. The basal outflow of GABA (in the range of ∼1–2 pmol/30 µl/30-min sample) after 2 and 8 days of treatment was not significantly different from that in control animals, but the 21-day treatment gave significant rises in the extracellular GABA concentration (up to ∼6–8 pmol/30 µl/30-min sample). Both inhibitors gave similar results. Depolarisation with 100 m M K+ gave large increases in GABA release in control (∼20–60 pmol/30 µl/30-min sample) and treated animals. The 8- and 21-day-treated animals showed significant increases in the stimulated release compared with control animals (∼80–100 pmol/30 µl/30-min sample). Excluding Ca2+ had no significant effect on either basal or stimulated release. The significant increases in K+-evoked release of GABA show that the increased intracellular pool of GABA is available for release, and this may be related to the anticonvulsant action of these compounds.  相似文献   
50.
The pH of the medium during the formation of liposomes by the cholate dialysis method affects their size. Liposomal size as measured by electron microscopy and volume equilibration is greatest if the dialysis step is carried out at pH 6 and decreases as the pH increases. The effect of liposome size on estimations of their incorporated choline carrier activity is illustrated.  相似文献   
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