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81.
Summary The objective of this study was to follow the development of microalbuminuria and nerve conduction velocity under continuous i.v. insulin therapy over a limited period of 4 months. For this purpose, 8 labile type I diabetics were selected (age 33±8 years, duration of diabetes 16±9 years) and treated conventionally with two insulin injections daily over 4 months. Afterwards, the same patients were treated with continuous i.v. insulin infusion and finally again with two injections daily over 4 months each. This procedure allowed each diabetic to serve as his own control. HbA1, microalbuminuria, nerve conduction velocity and relative refractory period of the ulnar nerve were checked at montly intervals. During the continuous i.v. infusion over 4 months, blood sugar values were significantly lower, glucosuria had disappeared almost completely and the glycosylated hemoglobin had fallen to near normal values. The mean rate of albumin excretion was 16±5 μg/min at rest and 76±26 μg/min during exercise (normal: 3.9±0.4 and 4.8±1.2 μg/min, respectively) and did not change significantly. Nerve conduction velocity in the ulnar nerve rose significantly under i.v. insulin therapy from 47.9±0.6 m/sec to 52±0.6 m/sec. Similarly, the relative refractory period of the same nerve fell significantly from 3.7±0.2 to 1.9±0.1 msec (i.e. to within normal range). It is concluded that functional disturbances of peripheral nerve can regress by improved blood sugar control with continuous i.v. insulin infusion over 4 months. On the other hand, incipient microangiopathy measured as microalbuminuria remains unchanged over the same period of time. If an improvement is at all possible, considerably longer periods of euglycemia are likely to be necessary. Supported by Grant No. 3.964-0.80 from the Swiss National Science Foundation.  相似文献   
82.
BACKGROUND: Gadolinium (Gd) magnetic resonance imaging (MRI) contrast agents are considered to be safe in patients with impaired renal function. Our study investigates a mechanism of severe iron intoxication with life-threatening serum iron levels in a haemodialysis patient following MRI with Gd-diethylenetriaminepentaacetic acid (Gd-DTPA) administration. His previous history was remarkable for multiple blood transfusions and biochemical evidence of iron overload. We hypothesized that Gd-DTPA may have an iron-mobilizing effect in specific conditions of iron overload combined with prolonged exposure to the agent. METHODS: For the in vitro study, Gd-DTPA was added to mice liver homogenate and iron metabolism parameters were measured after incubation in comparison with the same samples incubated with saline only. For the in vivo study, an experimental model of acute renal failure in iron-overloaded rats was designed. Previously iron-overloaded and normally fed rats underwent bilateral nephrectomy by renal pedicle ligation, followed by Gd-DTPA or saline injection. Iron and iron saturation levels were checked before and 24 h after Gd-DTPA or vehicle administration. RESULTS: Significant mobilization of iron from mice liver tissue homogenate in mixtures with Gd in vitro was seen in the control (saline) and in the experimental (Gd) groups (513+/-99.1 vs 1117.8+/-360.8 microg/dl, respectively; P<0.05). Administration of Gd-DTPA to iron-overloaded rats after renal pedicle ligation caused marked elevation of serum iron from baseline 143+/-3.4 to 570+/-8 microg/dl (P<0.0001). There were no changes of the named parameter, either in iron-overloaded anuric rats after saline injection or in normal diet uraemic animals, following Gd-DTPA administration. CONCLUSIONS: The combination of iron overload and lack of adequate clearance of Gd chelates may cause massive liberation of iron with dangerous elevation of free serum iron. It is highly recommended that after Gd contrast study, end-stage renal disease patients with probable iron overload should undergo prompt and intensive haemodialysis for prevention of this serious complication.  相似文献   
83.
FOREWORDPeritonealdialysisrepresentssoluteandfluidexchangemainlybetweenperitonealcapillarybloodanddialysissolutionintheperitonealcavity'CombinedwithhemodialySisandrenaltransplantation,peritonealdialysisisusedmainlyforthetreatmentofrenalfailure,particularlyforchronicfailure'In1976,Prof'Popovichdevelopedcontinuousambulatoryperitonealdialysis(CAPD)basingontheconceptofcontinuousequilibrationdialysis('1'Fromthenon,peritonealdialysisfounditsclinicaluse'Continuouscyclicperitonealdialysis(CCPD…  相似文献   
84.
心血管外科术后急性肾功能衰竭的处理   总被引:3,自引:0,他引:3  
目的:总结两组心血管外科术后急性肾功能衰竭病例的治疗经验,提出心血管外科术后急性肾功能衰竭的特点、早期诊断标准及处理原则。方法:17例心血管外科术后急性肾功能衰竭病例,以入院先后分为两组。第1组8例,第2组9例。回顾第1组病例的急性肾功能衰竭的治疗经验,总结腹膜透析、血液透析和血液滤过的优缺点。在第2组病例治疗中,以急性肾功能衰竭的早期诊断为前题,早期开始腹膜透析。同时,强调综合治疗的重要性。结果:第1组病例均死亡。第2组病例,7例存活(78%)。结论:心血管外科术后急性肾功能衰竭的早期诊断和早期肾功能替代疗法,是治疗成败的关键。腹膜透析简便易行,在急性肾功能衰竭的早期开始腹膜透析,可以收到良好效果,并以此作为心血管外科术后急性肾功能衰竭的首选肾功能替代疗法。  相似文献   
85.
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   
86.
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   
87.
Management of abdominal sepsis   总被引:2,自引:0,他引:2  
Introduction: Today the management of the different forms of peritonitis is generally standardised. The classification of primary and secondary peritonitis is well accepted. From a pathophysiological point of view, postoperative and post-traumatic peritonitis should be considered as independent entities. The bacteriological isolates from the inflamed peritoneal cavity do not correlate with the clinical course, and the occurrence of enterococci and bacteroides may be slightly related to ongoing infectious complications. Classification: Valuable scoring systems mainly rely on systemic signs of the septic disease and seem to better differentiate the prognosis of the disease than more surgically oriented scores do. Although the scoring systems did not allow any clinical decision, they should be used to help better compare patients treated in different institutions. The observation of the minor relevance of bacteriology and the superiority of general sepsis scores agrees with the fact that pre-existing septic organ dysfunction and pre-existing comorbidity are the main determinants of mortality. Treatment: Surgical therapy focuses on the control of the source of infection because it has been clearly shown that, without resolving the source of infection, the prognosis remains poor. Adjuvant surgical measures aim at the further reduction of the bacterial load in the peritoneal cavity. Planned relaparotomy, relaparotomy on demand, and continuous closed peritoneal lavage are used. Results: Clinical results proved these methods to be equally effective although pathophysiological considerations favour closed peritoneal lavage. Conclusion: Summarising the available data, we need a more sophisticated understanding of the pathophysiology of the peritonitis, and well-designed clinical studies are necessary to define the optimal surgical treatment modalities. Received: 27 November 1997  相似文献   
88.
Peritoneal desmoplastic small round cell tumors with divergent differentiation are recently described highly aggressive neoplasms with characteristic clinical, morphologic, and immunohistochemical features. This review covers 38 cases that have been reported in the literature. The average age of patients is 18.4 years, and males are affected twice as frequently as females. Tumors generally present as multiple peritoneal nodules without obvious organ involvement. Histology shows islands of small cells set in dense desmoplastic stroma. Immunohistochemical stains are usually positive for cytokeratins, epithelial membrane antigen, desmin, and vimentin. Many cases also stain for neuron-specific enolase but rarely for other neuroepithelial markers. Ultrastructural appearances range from undifferentiated small cells to larger epithelial elements. Paranuclear aggregates of intermediate filaments are characteristic. Dense-core granules and other neuroendocrine features have been described in a minority of cases. Some tumors respond to chemotherapy, but most patients die within months to a few years. The histogenesis of these tumors is uncertain.  相似文献   
89.
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   
90.
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   
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