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91.
92.
BACKGROUND: Peritoneal dialysis is associated with changes in membrane function that can lead eventually to ultrafiltration (UF) failure. Factors driving these changes are thought to include hypertonic glucose exposure, but previously reported associations are confounded by the presence of residual renal function. METHODS: Longitudinal membrane function (solute transport and UF capacity) were measured annually in a prospective cohort of 177 functionally anuric patients as part of the European Automated Peritoneal Dialysis Outcomes Study (EAPOS). Subgroup analysis was performed according to glucose exposure and icodextrin use at baseline. RESULTS: The whole cohort experienced an increase in solute transport and reduction in UF capacity at 12 and 24 months that could not be explained by informative censoring. These changes were accelerated and more severe in patients using either 2.27% or 3.86% glucose, or those not using icodextrin at baseline. These differences could not be explained by age, comorbidity score, previous time spent on renal replacement, differential dropout from the study, peritonitis rates, or, by definition, residual renal function. Patients using icodextrin at baseline had worse membrane function and were more likely to be diabetic. There was an association between membrane function changes and achieved 24-hour ultrafiltration over the 2-year study period. CONCLUSION: Anuric automated peritoneal dialysis (APD) patients experience significant detrimental changes in membrane function over a relatively short time period. Glucose appears to enhance these changes independent of residual renal function. Icodextrin use in these circumstances is associated with less deterioration in membrane function.  相似文献   
93.
OBJECTIVE: The prostate specific antigen (PSA) era has been associated with a grade migration towards moderately-differentiated (Gleason 5-7) prostate cancer. We investigated whether changes in interpretation of the Gleason system could be a contributing factor by reviewing the Gleason scores for prostate cancer in our region. PATIENTS AND METHODS: Records of patients with prostate cancer assigned a Gleason score between 1991-2001 were retrospectively reviewed. We analysed trends in Gleason score, method of diagnosis and age at diagnosis. Following this, 50 cases from the dataset were randomly selected (stratified to contain half Gleason 2-4 reports) and reviewed in a blinded manner by an uropathologist and given a new Gleason score. RESULTS: 2737 patients were diagnosed and given a Gleason score; 1484 by prostate biopsy (PB) and 1172 by transurethral resection of prostate (TURP). 273 radical prostatectomy (RP) specimens were received, although the results of pre-operative biopsies were available in only 192 of these patients. Over time, there was an increase in the proportion of patients with Gleason 5-7, and a significant decrease in reporting of Gleason 2-4 cancer (r2 = 0.81, p < 0.0001). In 1991, 24% of cancers were Gleason 2-4; in 2001 this had decreased to 2.4%. TURP was associated with more Gleason 2-4 reports (23%) compared with PB (13.2%) and RP (9.2%). On blinded review, all Gleason 2-4 reports were upgraded to Gleason 5-7 cancer (p < 0.001). CONCLUSION: Over time, the proportion of Gleason 2-4 prostate cancer reported has significantly decreased. Our study suggests that a change in practice by the pathologist is a significant factor in this grade migration.  相似文献   
94.
The United Network for Organ Sharing (UNOS) Expanded Criteria Donor (ECD) system utilizes pre-transplant variables to identify deceased donor kidneys with an increased risk of graft loss. The aim of this study was to compare the ECD system with a quantitative approach, the deceased donor score (DDS), in predicting outcome after kidney transplantation. We retrospectively reviewed 49 111 deceased donor renal transplants from the UNOS database between 1984 and 2002. DDS: 0-39 points; >or=20 points defined as marginal. Recipient outcome variables were analyzed by ANOVA or Kaplan-Meier method. There was a 90% agreement between the DDS and ECD systems as predictors of renal function and graft survival. However, DDS identified ECD- kidneys (10.7%) with a significantly poorer outcome than expected (DDS 20-29 points, n = 5,252). Stratification of ECD+ kidneys identified a group with the poorest outcome (DDS >or=30 points). Predictability of early post-transplant events (i.e. need for hemodialysis, decline of serum creatinine and length of hospital stay) was also improved by DDS. DDS predicted outcome of deceased donor renal transplantation better than the ECD system. Knowledge obtained by stratification of deceased donor kidneys can allow for improved utilization of marginal kidneys which is not achieved by the UNOS ECD definition alone.  相似文献   
95.
OBJECTIVE: To calculate the economic consequences of using alfuzosin 10 mg once daily for managing acute urinary retention (AUR) related to benign prostatic hyperplasia (BPH). METHODS: We examined whether alfuzosin use during hospitalization for AUR and for 6 months after a successful trial without catheter (TWOC) is cost effective compared to placebo and immediate prostatectomy, from the perspective of patients managed in the National Health Service (NHS) in the UK. A decision-analysis model was developed to estimate the costs of various treatment options within the first 6 months after a first episode of AUR. Clinical data were obtained from a large randomized clinical trial comparing alfuzosin 10 mg with placebo, and from published reports. Cost data were obtained from both NHS and resource-use data gathered during the clinical trial. A Monte Carlo analysis, allowing variability in all uncertain variables of the model, was used to calculate the uncertainty surrounding the results. RESULTS: Treating patients with alfuzosin during initial hospitalization for AUR and in the first 6 months after a successful TWOC generates a cost-saving of pounds 349 relative to placebo. Savings related to immediate prostatectomy were pounds 892; both savings were significant (P < 0.05). Alfuzosin treatment was associated with a lower rate of prostatectomy after discharge from hospital after a successful TWOC. CONCLUSION: Treatment with alfuzosin 10 mg once daily before and after a successful TWOC has both clinical and economic benefits. It decreases the need for emergency surgery for BPH and reduces treatment costs in the first 6 months.  相似文献   
96.
Background Flexible endoscopy is a vital component of gastrointestinal surgery. It has and will replace many of the surgical procedures now commonly performed. Flexible endoscopy, unfortunately, is not an integral part of surgical residency training based on resident operative experience as reported by the Residency Review Committee. Moreover, general surgeons have deferred the practice of flexible endoscopy to the gastroenterologists because of concerns over turf battles and referral patterns. The purpose of this study was to assess the overall case load and the economic impact of flexible endoscopy on the practice of general surgery in a community hospital setting.Methods This retrospective review was performed over a 6-month period. The total cases and the total billings of inpatient and outpatient procedures for a group practice of five general surgeons in a community hospital were evaluated. The billings were the actual charges based on current procedural terminology (CPT) codes for these procedures using the Medicare fee schedule.Results Of the 2,159 procedures performed, 1,154 involved flexible endoscopy cases accounting for 54% of all cases (1,154 of 2,159) performed from February 1, 2003 to July 31, 2003. Flexible endocopy accounted for 43% of the total charges. A. total of 46 surgical procedures and 216 future endoscopies were generated from the flexible endoscopic procedures. Future endoscopic cases were for surveillance of colonic neoplasia and Barrett’s esophagus.Conclusions Flexible endoscopy contributed to a major portion of the caseload and revenue generated by the general surgery group studied. The overall impact of flexible endoscopy is even greater than reported because of the future endoscopic surveillance cases or surgical interventions generated on the basis of endoscopic findings.  相似文献   
97.
98.
Long-term anticonvulsant drug therapy may lead to abnormalities of calcium metabolism resulting in osteomalacia. The prevalence and severity of altered calcium metabolism was studied in an adult outpatient population of persons with epilepsy receiving anticonvulsant therapy for a minimum of 2 years. Assessment of calcium metabolism was based on serum concentrations of calcium, phosphorus, alkaline phosphatase and 25-hydroxycholecalciferol and of plasma parathyroid hormone, intestinal absorption of isotopic calcium and skeletal bone mineral mass as determined by in vivo neutron activation or x-ray photodensitometry.

Thirty-nine patients who had been receiving anticonvulsant therapy for an average of 20 years were studied; none had clinical evidence of metabolic bone disease. Decreased serum calcium concentration was noted in 10%, decreased serum phosphorus concentration in 10% and elevated serum alkaline phosphatase concentration in 44%. The mean serum 25-hydroxycholecalciferol concentration was significantly lower (P < 0.001) than in a control group (11.6 v. 19.6 mg/mL). None of 18 patients studied had an increased plasma concentration of parathyroid hormone, and only 1 of 17 patients had decreased intestinal absorption of isotopic calcium. Bone mineral mass was decreased in 44% of 32 patients studied.

It was concluded that long-term treatment with anticonvulsant drugs leads to mild abnormalities of calcium metabolism and decreased bone mineral mass in a substantial percentage of adult outpatients with epilepsy. These abnormalities probably predispose the patients to the development of clinically significant metabolic bone disease.

  相似文献   
99.
Long-term follow-up of surgically treated thyrotoxic patients   总被引:2,自引:0,他引:2  
  相似文献   
100.
We report the cases of two laryngectomy patients who were diagnosed with de novo nasal polyposis, more than 15 years after their laryngectomies. This phenomenon has not previously been reported in the literature. We discuss the changes in nasal physiology of the laryngectomy patient, with regards to the aetiology of polyp formation, and highlight the importance of examining the nose in such patients.  相似文献   
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