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41.
Dialysis amyloidosis is one of the most incapacitating complicationsof long-term dialysis treatment. Quantitative assessment ofamyloid deposition using radiolabelled tracers has been recentlyproposed but convincing evidence of its validity in uraemicpatients remains to be provided. We studied the plasma kineticsof i.v. administered 125I-labelled serum amyloid P component(125I-SAP) in 20 chronic haemodialysis patients compared withthose of nine healthy volunteers and three non-dialysed patientswith systemic amyloidosis. Plasma clearance of the tracer wasabnormal in 17 of 20 dialysis patients in whom plasma radioactivitydeclined in a bi-exponential mode, in contrast to the single-exponentialslope observed in all healthy controls. 125I-SAP plasma half-lifeof the second component, probably reflecting metabolic clearance,was significantly prolonged in these dialysis patients comparedwith the healthy controls (35.3 versus 24.6 h, P<0.001).Among the long-term haemodialysis patients the calculated extravasculardistribution of 125I-SAP was significantly greater in thosewith severe arthropathy than in asymptomatic patients. Thesefindings demonstrate for the first time that SAP clearance isdisturbed in haemodialysis patients due to both failing renalelimination and retention in extravascular sites. The extravasculardiffusion is greatly enhanced in patients with clinical evidenceof amyloidosis. Therefore the study of plasma 125I-SAP kineticspromises to be a valuable tool to quantitate the extent of amyloidosis.  相似文献   
42.
Aspergillus peritonitis is a rare complication of continuousambulatory peritoneal dialysis. The case is described of a 68-year-oldman in whom Aspergillus fumigatus was isolated from the peritonealdialysate after recurrent peritonitis with Gram-negative rodsin association with diverticulosis. Treatment consisting ofremoval of the catheter and intravenous administration of amphotericinB followed by oral itraconazole was successful. A review of the sparse literature (12 cases) displays uncertaintiesregarding diagnostic awareness, culture diagnosis, and therapeuticmanagement. Next to institution of appropriate antifungal therapy,early removal the peritoneal dialysis catheter is recommended,as delayed removal of the catheter appears to be associatedwith increased mortality and morbidity.  相似文献   
43.
以P(St-Am·MG)对染料活性艳红(X-3B)溶液进行絮凝试验,考察了高聚物剂量及外加盐对絮凝效果的影响,并与无疏水基团的阳离子聚丙烯酰胺PAm·MG的絮凝能力进行了比较。发现絮凝体系无外加盐时,高聚物与染料的作用主要是通过静电力;有外加盐时,高聚物的电荷受到屏蔽,高分子链卷曲,PAm·MG的絮凝效果受到较大影响。而P(St-Am·MG)与X-3B之间存在疏水相互作用,受影响较小,此时P(St-Am·MG)的絮凝性能优于PAm·MG。用平衡渗析法研究了不同温度时甲醇和脲存在下P(St-Am·MG)与X-3B相互作用的热力学。证明了它们之间确实存在疏水相互作用。  相似文献   
44.
The formation of 1.25-dihydroxycholecalciferol (1.25-(OH)2D3after single intravenous injections of 1-hydroxycholecalciferol(1-OHD3) was examined in four patients with chronic renal failureon regular haemodialysis. Following 1–3µg 1-OHD3administered at weekly intervals, 1.25-(OH)2D3 appeared in thecirculation within 1 h, and peak concentrations were reachedbetween 2 h and 5 h. By 8 h serum 1.25-(OH)2D3 concentrationshad started declining and by 44 h they had returned to baselineafter 1µg 1-OHD3 but they were still above basal after2 and 3 µg by an average of 30 pmol/l. One week afterinjections, concentrations were back to basal in all patientsstudied. The serum 1,25-(OH)2D3 dose response to injected la-OHDwas linear, indicating ample capacity of the liver 25-hydroxylaseto further hydroxylate 1-OHD. However, examination of the individualresponses revealed lower increments in serum 1.25-(OH)3 concentrationsin the patients with the highest basal serum 25-hydroxyvitaminD concen trations. Intravenous 1-OHD3 may be useful in the furtherstudy of the interactions between 1.25-(OH)23 calcium and PTHin chronic renal failure, as well as of the hepatic metabolismof vitamin D.  相似文献   
45.
The five-factor taxonomy of personality traits has received increasing attention in the literature regarding personality correlates of health outcomes and behaviors. We examined the association of the five NEO Five-Factor Inventory dimensions to medical regimen adherence in a sample of 72 renal dialysis patients. Results indicated that Conscientiousness (Dimension III) is a five-factor trait significantly associated with adherence to the medication regimen. No other NEO-FFI dimension was significantly associated with patient adherence.  相似文献   
46.
目的 分析持续性腹膜透析(PD)治疗老年慢性肾功能衰竭(CRF)患者的临床效果,探讨PD在老年CRF患者中的应用经验.方法 回顾性分析89例老年CRF患者接受PD(简称老年PD组)治疗后的临床表现和生化指标、主要并发症、存活率、死亡原因等,并与53例非老年PD组相比较.结果 老年PD组的原发疾病以糖尿病(37.08%)、原发性高血压(30.34%)为主,而非老年PD组则以肾小球肾炎(54.72%)为主.两组患者的1年与3年存活率差异无统计学意义,腹膜炎仍是两组患者退出PD的主要原因.老年组的病死率明显高于非老年组,感染与心脑血管病是两组患者的主要并发症和死亡原因.低钾血症在老年PD患者中非常普遍.结论 腹膜透析在老年CRF患者的治疗中有效,但长期存活仍受腹膜炎、心脑血管病并发症的影响,老年PD患者的低钾血症应引起足够的重视.  相似文献   
47.
A serological and molecular study of hepatitis B virus (HBV) infection was carried out in dialysis units in Central Brazil. Between 1995 and 1999, serum samples from all HBsAg-positive hemodialysis patients (n = 43) were tested for HBeAg/anti-HBe and subtyping by monoclonal ELISA. HBV DNA was detected by PCR and positive samples were genotyped by restriction fragment polymorphism pattern (RFLP) methodology. TheHBsAg prevalence declined in this population during the survey period (12-5.8%). HBeAg and anti-HBe were detected in 23 (53.5%) and 18 (41.9%) sera, respectively. Thirty-six samples could be HBsAg subtyped: 21 were subtype ayw(3), 14 belonged to adw(2) and one was identified as adw(4). HBV DNA was present in 30 serum samples. Of these, 20 (66.7%) were genotype D, 9 (30%) genotype A, and 1 (3.3%) genotype F. In addition, the RFLP pattern could be determined in samples from 18/20 genotype D patients: D3 (10 strains), D7 (7 strains) and D4 (1 strain); from 8/9 genotype A patients: A1 (6 strains) and A3 (2 strains); and from the patient infected with genotype F: F1. Patterns D3 and D7 were associated closely with HBV infection in the two largest hemodialysis units studied. These findings confirm the value of the RFLP method as an effective molecular epidemiological tool for elucidating HBV transmission in hemodialysis units.  相似文献   
48.
A dialysis tubing was implanted in the adrenal gland of rats. Adrenomedullary secretion products were dialysed into Ringer solution in the awake animal. Catecholamines (CAs) and methionine-enkephalin (Met-Enk) were measurable under resting conditions. Epinephrine, norepinephrine and Met-Enk-like immunoreactive material increased following application of an immobilization stress for 5 min. The results demonstrate that adrenomedullary CAs and peptides are coreleased. They also demonstrate that Met-Enk-like immunoreactive material is released under stress.  相似文献   
49.
本实验比较糖元、鸡红细胞及两者复合使用对小鼠腹腔渗出细胞的影响,结果表明鸡红细胞和糖元一样能激活巨噬系和组织嗜碱系细胞,影响巨噬系细胞分化,鸡红细胞较糖元快;而影响组织嗜碱系细胞分化,糖元较鸡红细胞快。由于腹腔渗出细胞中存在原、幼巨噬细胞,按照血细胞发育是不可逆回的理论,推测腹腔巨噬细胞不是来源于血液循环中的单核细胞,而是来自血循环中的定向干细胞。本实验在腹腔渗出细胞中,首次发现组织嗜碱系细胞并描写其形态特征。  相似文献   
50.
腹膜透析病人的焦虑和抑郁水平与其病情变化的相关分析   总被引:23,自引:0,他引:23  
目的:探讨腹膜透析病人情绪障碍,即焦虑症状和抑郁症状的发生情况,以及与透析相关因素的关系.方法:88例腹膜透析病人,使用Hamilton焦虑量表和Hamilton抑郁量表评估其情绪状况,同时测定其营养状况、残余肾功能和透析充分性、以及炎症水平,记录心脑血管事件发生情况等.结果:本组腹膜透析病人焦虑症状的发生率为44.3%,抑郁症状的发生率为56.8%.具有糖尿病和心脑血管病史者的Hamilton焦虑评分和抑郁评分高于无此类病史者(P<0.05).SGA评分较高的病人Hamilton焦虑评分和抑郁评分也较高;焦虑评分和抑郁评分较高的病人,其血清白蛋白水平、蛋白质摄入水平、体重指数、上臂中段肌肉面积和脂肪面积均较低(r=0.22~0.60,P<0.05或P<0.01).结论:腹膜透析病人焦虑症状和抑郁症状的发生率较高,焦虑症状和抑郁症状与心脑血管系统疾病和糖尿病相关,并可能与营养不良的发生存在一定的关系.  相似文献   
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