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141.
CT导引下胸部病变穿刺活检影响诊断正确率因素分析   总被引:4,自引:0,他引:4  
目的 :探讨影响CT导引下胸部病变穿刺活检诊断正确率的因素。方法 :复习有手术病理、临床和影像学随访的胸部病变CT导引下穿刺活检 2 4 4例 ,依据手术病理、治疗反应及临床随访结果对活检病灶作出最终诊断 ,观察因素包括患者相关因素 (性别、年龄、有无肺气肿 )、病灶相关因素 (病灶大小、位置、有无空腔及病灶深度 )和操作相关因素 (患者的体位 )。结果 :胸部病变CT导引下穿刺活检诊断正确率为 82 .4 % ( 2 0 1 /2 4 4)。活检诊断正确率与病灶大小有关 ,诊断正确组和非正确组病灶大小分别为 3 .97± 1 .80cm和 3 .1 1± 1 .4 4cm(P <0 .0 5 )。患者性别、年龄、有无肺气肿、病灶位置、深度、有无空腔及患者体位对穿刺活检诊断正确率的影响无统计学意义。结论 :病灶大小是影响CT导引下胸部病变穿刺活检诊断正确率的主要因素  相似文献   
142.
CT引导下经皮穿刺活检对纵隔占位病变的诊断价值   总被引:6,自引:0,他引:6  
目的评价CT引导下经皮穿刺活检术在纵隔占位病变中的应用价值和安全性。方法采用弹簧式自动活检枪,在CT精确定位下对纵隔内占位病变行经皮穿刺活检,所获标本送病理组织学检查,并对穿刺准确性、病理确诊率和并发症发生情况进行分析。结果本组33例病灶穿刺成功率100%,病理确诊率85%,无一例发生并发症。结论CT引导下经皮穿刺活检术是一项操作方便,定位精确,穿刺准确率和病理确诊率高,安全可靠的介入放射诊断技术,对纵隔占位病变的定性诊断很有价值,值得临床推广应用。  相似文献   
143.
A technique for transperineal high-dose-rate (HDR) prostate brachytherapy and needle biopsy in a standard 1.5 T MRI scanner is demonstrated. In each of eight procedures (in four patients with intermediate to high risk localized prostate cancer), four MRI-guided transperineal prostate biopsies were obtained followed by placement of 14-15 hollow transperineal catheters for HDR brachytherapy. Mean needle-placement accuracy was 2.1 mm, 95% of needle-placement errors were less than 4.0 mm, and the maximum needle-placement error was 4.4 mm. In addition to guiding the placement of biopsy needles and brachytherapy catheters, MR images were also used for brachytherapy treatment planning and optimization. Because 1.5 T MR images are directly acquired during the interventional procedure, dependence on deformable registration is reduced and online image quality is maximized.  相似文献   
144.
目的 回顾性研究终末期肾脏疾病(end stage renal disease,ESRD)血液透析病人原发疾病构成及其相关因素。方法 收集ESRD血液透析病人1108例,分析其原发疾病构成、年龄、性别、透析治疗持续时间、转归、生存率和死亡原因。结果 301例病人透析时间超过3个月,其中43.9%仍在进行血液透析治疗,最长者已存活13年;13.0%病人已行肾脏移植;19.9%转至外院治疗;7.3%改为腹膜透析;1.3%因经济困难放弃治疗;14.6%病人死亡。ESRD维持性血液透析病人1年生存率为93.53%,3年生存率为68.92%。5年生存率62.51%。死亡原因为心血管事件占54.5%,脑血管意外占20.5%。结论 本组病人以中、老年为主,男性多见。ESRD血液透析病人主要原发疾病为慢性肾小球肾炎,主要死亡原因为心血管事件和脑血管意外。  相似文献   
145.
BACKGROUND: Total excision of colonic polyps is not always attainable and in some patients it is clinically contraindicated. Also, a resected polyp may be lost at any step between its endoscopic removal and its embedding in paraffin. The aim of this study was to compare the histological features of colonic polyps as analysed by the study of biopsy-forceps obtained samples with those assessed on scrutinizing the totally resected growths. PATIENTS AND METHODS: This prospective study included a cohort of 59 patients in whom, in the course of an elective colonoscopy, a total excision of a 6 mm-sized or larger polyp was called for. Sizeable biopsies were obtained by means of an Olympus Multibyte forceps prior to the total polypectomy. Subsequent to the study of the polypectomy specimens, the forceps biopsy samples were submitted for histological examination. The pathologists were blinded as to the source of the tissue they were studying. The diagnoses rendered by evaluating the biopsy samples and polypectomy specimens of each patient were contrasted with each other. RESULTS: Major discrepancies between the histological features of the fragments captured by the biopsy-forceps and the factual nature of the totally removed polyps were uncovered in 11 (18.6%) of 59 cases. Intriguingly, the grade of the tumours was underrated in all the 11 cases, as judged by contrasting the tentative diagnoses of the forceps-biopsies with the decisive diagnoses of the polypectomies. Importantly, 2 adenocarcinomas would have been missed by just looking at the forceps-retrieved sample. CONCLUSIONS: In our experience, a discordance of 18.6% is to be expected between the diagnoses rendered after examining forceps-biopsies of and totally excised colonic polyps. Nevertheless, it is advisable to procure biopsies prior to the excision of the growths, because on those occasions in which patients' growths cannot be removed or have not been retrieved for one reason or another, a small forceps-captured tissue sample correctly reflects the characteristics of the polyp in 81.4% of the cases. Finally, the biopsies may be discarded in the event that total removal was successful.  相似文献   
146.
神经内镜治疗脑室内病变   总被引:7,自引:2,他引:5  
目的探讨脑室内病变的神经内镜治疗。方法应用神经内镜对68例脑室内病变进行治疗,其中松果体区肿瘤16例,囊性颅咽管瘤15例,丘脑肿瘤14例,脑室内囊肿16例,侵及室管膜下的胼胝体肿瘤3例,侧脑室脉络丛乳头状瘤2例,侧脑室猪囊尾蚴病1例,侧脑室内分流管脱落1例。结果随访17~69个月,56例有效,12例死于肿瘤扩散。无严重并发症。结论对脑室内病变选择性应用神经内镜治疗安全、有效。  相似文献   
147.
BACKGROUND: Cyanide is a toxic agent, and its detoxification product, thiocyanate, may be a major pathogenetic substance in uraemia. Recent studies examining the myeloperoxidase(MPO)/thiocyanate system have suggested a link between thiocyanate and atherosclerosis. However, inaccuracies in conventional assays for cyanide and thiocyanate have limited the understanding of their metabolism in haemodialysis (HD) patients. METHODS: We used high-performance liquid chromatography to measure cyanide in erythrocytes and thiocyanate in plasma in 43 HD patients and in a group of 46 healthy controls that included 15 current smokers. To clarify the metabolic conversion of cyanide to thiocyanate in uraemic patients, we also measured cysteine and sulfate. We then used stepwise regression analysis to analyse factors that determine erythrocyte cyanide and plasma thiocyanate. RESULTS: Mean cyanide and thiocyanate were significantly greater in HD patients than in non-smoking controls. However, cyanide was far below lethal concentrations in dialysis patients. Thiocyanate was six to seven times greater in HD patients than in non-smoking controls, and decreases in thiocyanate following dialysis were only 19.3+/-3.5%. Multiple regression analysis showed a positive correlation between cyanide and thiocyanate in controls, but a negative correlation in HD patients. In patients, an inverse relationship between thiocyanate and BUN was also observed. CONCLUSIONS: The elevation of thiocyanate in patients undergoing dialysis probably is secondary to both limited efficiency of HD and deranged metabolism of cyanide and thiocyanate. Because thiocyanate is a preferred substrate for MPO, it may play a role in uraemic complications including cardiovascular events.  相似文献   
148.
Abstract:  Angiotensin-converting enzyme inhibitor (ACEI) has become recognized as agents that have renoprotective effects in the treatment of progressive renal diseases including post-transplant kidneys. Previously we demonstrated the safety and effectiveness of ACEI treatment on the hypertensive proteinuric post-transplant patients ( N  = 10) who had been followed up for 12 months. However, not all patients show good response in urinary protein reduction. We aimed to analyse the histopathological factor(s) affecting the responsiveness of proteinuria to ACEI treatment. Fourteen post-transplant patients with proteinuria who were treated with ACEI and underwent allograft biopsy were analysed. Eight patients showed 50% or more reduction in proteinuria (responder). The other 6 patients showed less (< 50%) reduction in proteinuria (non-responder). There was no difference in clinical characteristics (BP, renal function, donor age, recipient body mass index), dietary sodium or protein intake, and diuretic use between the two groups. As a histopathological characteristic, glomerular size in responder group was significantly larger than that in non-responder group. This suggests that the large glomerular size at least partly contributes to the responsiveness in urinary protein reduction to ACEI treatment in kidney allograft recipients with proteinuria.  相似文献   
149.
INTRODUCTION. This report describes the current status of nephrology and renal replacement therapy (RRT) in Romania, a country with previously limited facilities, highlighting national changes in the European context. METHODS: Trends in RRT development were analysed in 2003, on a national basis, using the same questionnaires as in previous surveys (1991, 1995). Survival data and prognostic risk factors were calculated retrospectively from a large representative sample of 2284 patients starting RRT between January 1, 1995 and December 31, 2001 (44% of the total RRT population investigated). RESULTS: In 2003, RRT incidence [128 per million population (p.m.p.)] and prevalence (250 p.m.p.) were six and five times higher, respectively, than in 1995. The annual rate of increase in the stock of RRT patients (11%) was supported mainly by an exponential development of the continuous ambulatory peritoneal dialysis (CAPD) population (+600%), while the haemodialysis (HD) growth rate was stable (+33%) and renal transplantation made a marginal contribution. Renal care infrastructure followed the same trend: nephrology departments (+100%) and nephrologists (+205%). The characteristics of RRT incident patients changed accordingly to current European epidemiology (increasing age and prevalence of diabetes and nephroangiosclerosis). The estimated overall survival of RRT patients in Romania was 90.6% at 1 year [confidence interval (CI) 89.4-91.8] and 62.2% at 5 years (CI 59.4-65.0). Patients' survival was negatively influenced (Cox regression analysis) by age >65 years (P < 0.001), lack of pre-dialysis monitoring by a nephrologist [P = 0.01, hazards ratio (HR) = 0.8], severe anaemia, lack of erythropoetin treatment (P < 0.001, HR = 0.6), and co-morbidity, e.g. cardiovascular diseases (P < 0.001, HR = 1.8) and diabetes mellitus (P < 0.001, HR = 2.2). CONCLUSIONS: Although the rate of increase in RRT patient stock in 1996-2003 in Romania was the highest in Europe, the prevalence remained below the European mean. As CAPD had the greatest expansion, followed by HD, an effective transplantation programme must be set up to overcome the imbalance. The quality of RRT appears to be good and survival was similar to that in other registries. Further evolution implies strategies of prevention, based on national surveys, supported by the Romanian Renal Registry.  相似文献   
150.
Abstract:  We retrospectively studied the occurrence of vesicoureteral reflux (VUR)-associated pyelonephritis using renal biopsies obtained from the transplanted kidneys, and correlated the histological changes with clinical parameters. Out of a total of 131 renal biopsies performed between 1990 and 2001 on renal transplant patients at the department of Urology of Nagasaki University Graduate School of Biomedical Sciences, 12 patients showed pyuria more than twice in a single year. Seven of these 12 patients were available for determining VUR by voiding cystourethrography (VCUG). Cystoureterography demonstrated VUR in three of seven studied patients with pyuria. A histopathological examination revealed dilatation of both proximal and distal tubules in renal biopsies of transplant patients with VUR, compared to renal biopsies of transplant patients without VUR, or non-transplanted patients with thin membrane disease. One of the patients with VUR showed advanced features of chronic pyelonephritis in four consecutive biopsies at different time points, suggesting a late stage of reflux nephropathy in the transplanted kidney. We conclude from our study that the occurrence of VUR-related pyelonephritis may be one of the important long-term complications in the survival of renal allografts.  相似文献   
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