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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   
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Background In recent years, the technique of sentinel lymph node (SLN) mapping has been applied to colorectal cancer. One aim was to ultrastage patients who were deemed node negative by routine pathologic processing but who went on to develop systemic disease. Such a group may benefit from adjuvant chemotherapy.Methods With fully informed consent and ethical approval, 37 patients with primary colorectal cancer and 3 patients with large adenomas were prospectively mapped. Isosulfan blue dye (1 to 2 mL) was injected around tumors within 5 to 10 minutes of resection. After gentle massage to recreate in vivo lymph flow, specimens were placed directly into formalin. During routine pathologic analysis, all nodes were bivalved, and blue-staining nodes were noted. These later underwent multilevel step sectioning with hematoxylin and eosin and cytokeratin staining.Results SLNs were found in 39 of 40 patients (98% sensitivity), with an average of 4.1 SLNs per patient (range, 1–8). In 14 of 16 (88% specificity) patients with nodal metastases on routine reporting, SLN status was in accordance. Focused examination of SLNs identified occult tumor deposits in 6 (29%) of 21 node-negative patients. No metastatic cells were found in SLNs draining the three adenomas.Conclusions The ability to identify SLNs after formalin fixation increases the ease and applicability of SLN mapping in colorectal cancer. Furthermore, the sensitivity and specificity of this simple ex vivo method for establishing regional lymph node status were directly comparable to those in previously published reports.Presented at the British Society of Gastroenterology, Glasgow, United Kingdom, 2004; the American Society of Colon and Rectal Surgeons, Dallas, Texas, 2004; and the Association of Coloproctologists of Great Britain and Ireland, Birmingham, 2004.  相似文献   
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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   
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Background: There are little data available on the prevalence of chronic obstructive pulmonary disease (COPD) in the United Kingdom. The Northern Ireland Cost and Epidemiology of Chronic Obstructive Pulmonary Disease (NICECOPD) study is a two-stage survey to examine the prevalence of obstructive lung disease in a general population sample in the Greater Belfast area. Methods: In stage one 4000 subjects aged 40–69 years were selected at random from the general population. They were posted a short screening questionnaire concerning respiratory symptoms. Respondents were divided into ‚symptomatic’ and ‚asymptomatic’ groups according to their responses. In stage two, a sample of symptomatic and asymptomatic subjects completed a more intensive assessment that included a detailed questionnaire on medical history, spirometry, skin allergy testing and serial peak flow measurements. Spirometric criteria for airflow obstruction were FEV1/FVC ratio of <70% with FEV1 < 80% predicted. Subjects were assigned diagnoses according to a pre-arranged protocol. Results: The survey was conducted from May 1999 to May 2001. There was a 67% response rate to the stage 1 screening questionnaire and 1330 responders were identified as being eligible to take part in stage 2. In total, 722 subjects completed a detailed assessment (50.8% Male, symptomatic, n = 326; asymptomatic, n = 396). COPD was diagnosed in 12.3% (8.8, 15.8) of the symptomatic and 2.2% (0.8, 3.6) of the asymptomatic group. The estimated prevalence of obstructive lung disease in the total population age 40–69 years was 14.4%: 6.3% COPD; 7.2% asthma; 0.9% with indeterminate airflow obstruction. In men, the prevalence of COPD varied from 4.9% in those aged 40–49 years to 12.3% in those aged 60–69 years and in women, varied from 1.4% in 40–49 years of age to 4.5% in 60–69 years. Conclusion: The data suggest that COPD and asthma are common conditions in the general population and should inform future plans to address the burden of disease  相似文献   
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BACKGROUND: The effects of vitamin B-6 status on steady-state kinetics of homocysteine metabolism in humans are unclear. OBJECTIVE: The objective was to determine the effects of dietary vitamin B-6 restriction on the rates of homocysteine remethylation and synthesis in healthy humans. DESIGN: Primed, constant infusions of [(13)C(5)]methionine, [3-(13)C]serine, and [(2)H(3)]leucine were conducted in healthy female (n=5) and male (n=4) volunteers (20-30 y) before and after 4 wk of dietary vitamin B-6 restriction (<0.5 mg vitamin B-6/d) to establish whether vitamin B-6 status affects steady-state kinetics of homocysteine metabolism in the absence of concurrent methionine intake. Effects of dietary vitamin B-6 restriction on vitamin B-6 status, plasma amino acid concentrations, and the rates of reactions of homocysteine metabolism were assessed. RESULTS: Dietary vitamin B-6 restriction significantly reduced plasma pyridoxal 5-phosphate (PLP) concentrations (55.1 +/- 8.3 compared with 22.6 +/- 1.3 nmol/L; P=0.004), significantly increased plasma glycine concentrations (230 +/- 14 compared with 296 +/- 15; P=0.008), and significantly reduced basal (43%; P < 0.001) and PLP-stimulated (35%; P=0.004) lymphocyte serine hydroxymethyltransferase activities in vitro. However, the in vivo fluxes of leucine, methionine, and serine; the rates of homocysteine synthesis and remethylation (total and vitamin B-6-dependent); and the concentrations of homocysteine, methionine, and serine in plasma were not significantly affected by dietary vitamin B-6 restriction. CONCLUSIONS: Moderate vitamin B-6 deficiency does not significantly alter the rates of homocysteine remethylation or synthesis in healthy young adults in the absence of dietary methionine intake.  相似文献   
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The methylenetetrahydrofolate reductase (MTHFR) 677C-->T polymorphism is thought to influence the partitioning of 1-carbon units between methylation and other components of 1-carbon metabolism and to influence the risk and etiology of several major cancers and cardiovascular disease. Our objective was to determine the effect of the MTHFR 677C-->T polymorphism and folate status on the relative rate and extent of in vivo synthesis of DNA precursors. Adequately nourished, healthy women (9 CC, 9 TT) were infused with [3-(13)C]serine and [(13)C(5)]methionine for 9 h before and after 7 wk of consumption of a low-folate diet. Blood was drawn over 5 d for monocyte DNA isolation. Isotopic enrichment of the nucleosides in DNA digests was determined by LC-MS/MS. Maximum thymidine enrichment tended to be higher (P = 0.07) in TT than in CC subjects, suggestive of marginally higher mean thymidylate synthesis. However, the subset of TT subjects who exhibited formyltetrahydrofolate in erythrocytes (an indicator of 1-carbon partitioning) had greater (P = 0.036) thymidine enrichment than CC subjects, who had no erythrocyte formyltetrahydrofolate. Purine enrichment was not affected by genotype or folate depletion. However, the deoxyadenosine to deoxyguanosine enrichment ratio was significantly higher in TT subjects, suggesting a greater relative rate of adenine synthesis. The approximately 40% greater (P = 0.012) labeling of the methyl group of methyldeoxycytidine during folate depletion suggests a change in the origin of this 1-carbon unit. This is the first time that 1-carbon incorporation into human DNA has been measured in vivo after infusion of (13)C-labeled 1-carbon precursors. These findings support the feasibility of further assessment of factors affecting deoxynucleotide synthesis and DNA methylation in human 1-carbon metabolism.  相似文献   
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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   
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