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141.
We report a case of leiomyosarcoma of the renal vein, which is a rare tumor with no more than 30 cases found in the published English language literature. This case demonstrates encasement of the renal artery by the tumor mass, a previously unreported manifestation. The present study could be useful in considering this rare tumor in the differential diagnosis of renal hilar tumors.  相似文献   
142.
Background and Aims: Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients.  相似文献   
143.
BACKGROUND: End-stage renal disease patients have a poor quality of life (QoL), suffer from impaired cognitive functioning, and their electroencephalogram (EEG) shows abnormalities. Conventional haemodialysis (CHD) only partially restores these disorders. Short daily haemodialysis (SDHD) has been reported to improve QoL, but effects on cognitive functioning and EEG have yet to be described. METHODS: Of the 13 patients (11 male, 2 female, age 45.5 +/- 8.1 years), 11 completed the Kidney Disease Quality of Life and Affect Balance Scale questionnaires, 10 underwent neuropsychological testing, and all 13 underwent EEG examination. For the neuropsychological assessments, nine patients (six male, three female, age 45.4 +/- 12.6) who remained on the CHD schedule, served as controls. The dialysis schedule of thrice-a-week for 4 h was changed in the experimental group to six times a week for 2 h (SDHD) over a period of 6 months and back to thrice a week for 4 h. RESULTS: When on SDHD, patients rated several dimensions of health-related QoL as being improved. After resuming CHD, one of these dimensions again decreased and several others worsened even lower than baseline. Cognitive functioning did not change when compared with control data. On the EEG, alpha peak frequency increased slightly when on SDHD but decreased significantly after resuming CHD. CONCLUSIONS: SDHD improves health-related QoL, but has no clear effects on cognitive functioning and EEG. Resumption of CHD after SDHD decreases aspects of QoL and EEG alpha peak frequency but has no effect on cognitive functioning.  相似文献   
144.
Objective: To compare renal sodium transport, using fractional excretions of lithium(FELi) as a marker of proximal tubule sodium reabsorption, between hypertensive and non-hypertensive ouabain-treated rats and further to elucidate the role of ouabain in pathogenesis of hypertension. Methods: Thirty male Sprague-Dawley rats weighting 180-200 g were randomly divided into normal control group and ouabain treated group. Rats were infused with 1 ml/kg·d normal saline or 27. 8μg/kg·d ouabain in-traperitoneally once a day respectively. Systolic blood pressure (SBP), heart rate and body weight were recorded weekly. Rats were sacrificed 6 weeks after treatment. Blood and 24-hour urine sample were collected to measure the serum and urinary concentration of sodium, trace lithium and creatinine. Endogenous creatinine clearance rate(Ccr), fractional excretions of sodium (FENa), fractional excretions of lithium (FELi) and fractional reabsorption of sodium in the postproximal tubules (FDRNa) were calculated. Ouabain levels of plasma and renal tissue, plasma renin activity, angiotensin I and aldosterone concentration were determined. Results: 65% of the ouabain-treated rats achieved significantly higher SBP after 4 weeks, compared with that of the saline control groups or self baseline (P<0. 01). But in the other 35% of the ouabain-treated rats, their SBP was similar with control group during the experiment (P>0. 05). The body weight, heart rate and food intake between the 3 groups were no significant differences (P> 0. 05). FELi and FDRNa were significantly lower in ouabain-hypertensive group compared with ouabain-non-hypertensive group and control group(P<0. 01 and P<0. 05). The FEu and FDRn, of ouabain-nonhyper-tensive groups were similar with control group(P>0. 05). Ccr and FENa were comparable between the 3 groups (P>0. 05). Plasma and renal tissue ouabain levels, plasma renin activity, angiotensin I and aldosterone contents in ouabain-hypertensive rats were comparable with ouabain-nonhypertensive rats. Conclusion: Increase of proximal tubule sodium reabsorption play an important role in the pathogenesis of ouabain-hypertensive rats. The change of renal sodium transport may result from regulation to renal Na+ , K + -ATPase by ouabain.  相似文献   
145.
Graft thrombosis is the most common cause of first year graft failure in pediatric renal transplantation. The North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) database was analyzed for cases of graft failure due to thrombosis among patients transplanted from 1998 to 2004. The impact of interleukin-2 (IL-2) receptor antagonists as induction therapy was determined. There were a total of 51 graft failures due to thrombosis among the 2750 reported renal transplants (1.85%) (95% CI (1.39%, 2.41%)). This represents the most common cause of graft loss during the first year post-transplant accounting for 35% of first year losses and 18% of all graft losses. The incidence of thrombosis among patients who received IL-2 receptor antibodies was 1.07% (12/1126) compared to 2.40% (39/1624) among patients who did not (OR 0.44, 95% CI 0.23, 0.84, p = 0.014). Use of IL-2 receptor blockade was the only significant prognostic factor in a multivariate model with previously identified risk factors. Analysis of NAPRTCS data found that the use of IL-2 receptor antibodies as induction therapy is associated with a significantly decreased risk of graft failure due to thrombosis. This provocative finding requires further investigation to determine whether thrombotic failure can be decreased by this therapeutic strategy.  相似文献   
146.
AIMS: In the presence of impaired renal function, patients require less insulin mainly because insulin clearance is prolonged. The aim of this study was to evaluate the insulin requirement related to glomerular filtration rate (GFR) in nephropathic Type 1 and Type 2 diabetic patients. METHODS: In a retrospective study we compared insulin requirement in 20 nephropathic Type 1 diabetic patients and 20 insulin-treated Type 2 diabetic patients from the onset of overt nephropathy until the final stage of renal disease. All patients had proteinuria > 0.5 g/24 h and creatinine clearance >/= 80 ml/min per 1.73 m2 at baseline. Creatinine clearance, urinary protein excretion, glycated haemoglobin and the required insulin doses were determined 3- to 6-monthly, basal C-peptide was measured at the beginning and the end of the observation period. The required insulin doses were evaluated at creatinine clearance rates of 80, 60, 40, 20 and 10 ml/min per 1.73 m2 (or at the initiation of dialysis treatment). RESULTS: The insulin requirement of patients with Type 1 diabetes was reduced from 0.72 +/- 0.16 IU/kg per day at a creatinine clearance rate of 80 ml/min, to 0.45 +/- 0.13 IU/kg per day at a creatinine clearance rate of 10 ml/min (decrement of 38%, P < 0.001). The insulin dose required by Type 2 diabetic patients was reduced from 0.68 +/- 0.28 IU/kg per day at a creatinine clearance rate of 80 ml/min to 0.33 +/- 0.19 IU/kg per day at a clearance rate of 10 ml/min (decrement 51%, P < 0.001). The fall in GFR, urinary protein excretion and glycated haemoglobin levels was similar in the two groups. In patients with Type 2 diabetes, C-peptide levels at the beginning and the end of renal function impairment were 2.2 (0.4-7.3) vs. 2.7 (0.1-4.9) ng/ml (NS). The reduction in insulin requirement was approximately the same in patients with an initial C-peptide level < 1.0 and in those >/= 1.0 ng/ml (decrement 57% vs. 46%). CONCLUSIONS: The reduction in insulin requirement in renal insufficiency is similar in Type 1 and insulin-treated Type 2 diabetic patients. In subjects with Type 2 diabetes, the residual insulin secretion has no impact on the reduction in insulin requirement dependent on the GFR.  相似文献   
147.
促红细胞生成素心肌保护作用的研究进展   总被引:4,自引:0,他引:4  
促红细胞生成素(erythropoietin,EPO)是一种造血细胞生长因子,主要用于治疗多种原因所致的贫血。近年来其非造血生物作用逐渐引起关注,EPO具有组织保护作用,这一作用涉及多种不同组织和细胞,心肌保护一直是心血管病研究领域重要、关键的课题。EPO对心肌保护的作用近两年已渐有报道,这无疑为临床心肌保护的研究提供了新的思路和方向。现就EPO心肌保护作用的相关研究成果、发现以及有待解决的问题作一综述。  相似文献   
148.
目的评价腹腔镜与开放性肾囊肿去顶术的临床疗效。方法回顾性分析采用经后腹腔镜和经腹腔镜行肾囊肿去顶术21例,其中经腹腔5例,经后腹腔16例,与开放性手术16例比较。结果手术时间,术中平均出血量,术后下床活动时间,术后住院天数,术后并发症腹腔镜组均优于开放手术组,住院费用腹腔镜组略高于开放性手术组。结论腹腔镜肾囊肿去顶术治疗单纯性肾囊肿安全、有效。应成为治疗单纯性肾囊肿的首选方法。  相似文献   
149.
BACKGROUND: Reactive oxygen species play a major role in the development of endothelial dysfunction. It is as yet unspecified whether increased oxidative stress contributes to endothelial dysfunction of the renal vasculature in patients with type 2 diabetes. METHODS: Renal haemodynamics were studied in 20 patients with type 2 diabetes and arterial hypertension (age 62 +/- 5 years) and 20 non-diabetic hypertensive patients at baseline and following infusions of the nitric oxide synthase inhibitor, N(G)-monomethyl-L-arginine (L-NMMA; 4.25 mg/kg); the substrate of nitric oxide synthase, L-arginine (100 mg/kg); and the antioxidant, vitamin C (3 g, co-infused with L-arginine 100 mg/kg). RESULTS: The response of renal plasma flow (RPF) to L-NMMA (-54 +/- 62 and -45 +/- 42 ml/min/1.73 m(2); P = NS) and L-arginine (+46 +/- 36 and +49 +/- 25 ml/min/1.73 m(2); P = NS) was not different between diabetic and non-diabetic patients. In contrast, vitamin C induced a more pronounced increase in RPF in diabetic than in non-diabetic patients when co-infused with L-arginine (+71+/-47 and +43+/-33 ml/min/1.73 m(2); P<0.05). CONCLUSIONS: The difference in the response of renal perfusion to an antioxidant suggests increased formation of reactive oxygen species and thereby reduced nitric oxide bioavailability in the renal vasculature of patients with type 2 diabetes.  相似文献   
150.
AIM: To study the association between age and clinical characteristics of renal cell carcinoma in adult patients. METHODS: Three hundred and ten patients with renal cell carcinoma were classified into three groups: or=60 years group. The clinical characteristics of the three groups were compared to define the association. RESULTS: The male/female ratio was 1.3/1, 2.0/1, 3.3/1 in the three groups, respectively, and a significant difference appeared when comparing the or=60 years group (P=0.010). The respective percentage of incidental renal cell carcinoma was 27.9%, 43.2%, 31.2%, and it was significantly higher in the 41-59 years group than the >or=60 years group (P=0.047). The incidence of poorly differentiated renal cell carcinoma decreased with age increasing (11.6% vs 5.2% vs 2.7%), and there was significant difference between the or=60 years group (P=0.038). In the 相似文献   
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