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41.
Re-resection for gallbladder carcinoma incidentally discovered after cholecystectomy is routinely advocated. However, the incidence of finding additional disease at the time of re-resection remains poorly defined. Between 1984 and 2006, 115 patients underwent re-resection at six major hepatobiliary centers for gallbladder carcinoma incidentally discovered during cholecystectomy. Data on clinicopathologic factors, operative details, TNM tumor stage, and outcome were collected and analyzed. Data on the incidence and location of residual/additional carcinoma discovered at the time of re-resection were also recorded. On pathologic analysis, T stage was T1 7.8%, T2 67.0%, and T3 25.2%. The median time from cholecystectomy to re-resection was 52 days. At the time of re-resection, hepatic surgery most often consisted of formal segmentectomy (64.9%). Patients underwent lymphadenectomy (LND) (50.5%) or LND + common bile duct resection (43.3%). The median number of lymph nodes harvested was 3 and did not differ between LND alone (n = 3) vs LND + common duct resection (n = 3) (P = 0.35). Pathology from the re-resection specimen noted residual/additional disease in 46.4% of patients. Of those patients staged as T1, T2, or T3, 0, 10.4, and 36.4%, respectively, had residual disease within the liver (P = 0.01). T stage was also associated with the risk of metastasis to locoregional lymph nodes (lymph node metastasis: T1 12.5%; T2 31.3%, T3 45.5%; P = 0.04). Cystic duct margin status predicted residual disease in the common bile duct (negative cystic duct, 4.3% vs positive cystic duct, 42.1%) (P = 0.01). Aggressive re-resection for incidental gallbladder carcinoma is warranted as the majority of patients have residual disease. Although common duct resection does not yield a greater lymph node count, it should be performed at the time of re-resection for patients with positive cystic duct margins because over one-third will have residual disease in the common bile duct. Presented at the 48th Annual Meeting of the Society for Surgery of the Alimentary Tract at Digestive Week 2007, Plenary Session, Washington, DC, March 23, 2007.  相似文献   
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Many quantitative imaging protocols that make use of a metabolite-corrected arterial input function require the use of a mathematic model to describe the rate of metabolism of the radioligand. Commonly, parametric models are fit to metabolism data and then the fitted model is used to correct the plasma input function. (11)C-WAY 100635 is a rapidly metabolized radioligand used extensively in mapping the 5-hydroxytryptamine receptor 1A system. METHODS: To evaluate the adequacy of fit of 4 metabolite models, we examined data from 92 subjects who received an injection of (11)C-WAY 100635, were imaged with PET, and underwent measurement of total plasma concentration and metabolites. The performance of these models was assessed according to residual plots, as well as fit and information criteria. RESULTS: The study showed that the choice of model has a substantial effect on the resulting estimates of outcome measures. CONCLUSION: Among the models considered, the Hill model provides the best fit across all criteria.  相似文献   
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BACKGROUND: The Heart Failure Survival Score (HFSS) has been previously shown to effectively risk-stratify patients under evaluation for heart transplantation. However, this model was developed before broad use of beta blockade. We hypothesized that the prognostic tool would retain its ability to risk stratify patients treated with beta-blockers. METHODS: We collected clinical data on 524 consecutive patients referred for heart transplantation from 1994 to 2001. Kaplan-Meier survival analysis and multivariable Cox regression analysis were performed with events defined as death, left ventricular assist device placement, or United Network of Organ Sharing 1 heart transplantation. RESULTS: Kaplan-Meier analysis of the patient population revealed effective discrimination by the survival score both for beta-blocker treated and untreated patients (both p <0.0001). Two-year event-free survival was 94% +/- 2% and 84% +/- 4% for beta-blocker and no beta-blocker patients in the low-risk HFSS strata. Cox proportional hazard modeling showed that HFSS strata (medium risk: HR 2.65, 95% CI 1.75-4.02, p <0.001; high risk: HR 5.51, 95% CI 3.64-8.33, p <0.001) and beta-blocker treatment (HR 0.45, 95% CI 0.31-0.64, p <0.001) were significant predictors of event-free survival. Receiver operating curves (area under the curve) for HFSS strata used to predict 2-year events were similar for beta-blocker treated (0.78 +/- 0.04) and untreated (0.80 +/- 0.03) patients. CONCLUSIONS: The HFSS provides effective risk stratification with or without beta-blocker therapy. Consideration of beta-blocker therapy with survival score strata improves outcome prediction in patients evaluated for heart transplantation.  相似文献   
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Conclusion  The ACCF/ASNC AC for SPECT MPI provides recommendations for the appropriate use of SPECT MPI. After the publication of the AC document in 2005, the AC has been used by nuclear cardiology practices with many clinical studies evaluating the list of indications in routine clinical practice. From these data. ASNC recommends minor but important changes to the indication list, suggesting the addition of 6 new indications and the modification of the definitions for “chest pain syndrome” and “CHD high risk.”. An objective review of existing indications focused on only those indications that had significant variability among the reviewers (n=20). These indications were reviewed in the presence of existing and new evidence-based data, and ASNC recommends that the grades for 6 indications be re-evaluated. The AC for SPECT MPI will require periodic review as new evidence becomes available or as clinical practice evolves. ASNC recognizes the importance of these criteria to improve the quality of patient care, and it will continue to play a key role in assembling the information for this ongoing review. From the current summary of evidence, ASNC consensus opinions, and ASNC recommendations in this document, ASNC strongly recommends that the AC guidelines be reviewed Prepared by the American Society of Nuclear Cardiology Quality Assurance Subcommittee for Quality in Imaging Standards. Reviewed by members of the American Society of Nuclear Cardiology Quality Assurance Committee. Approved by the American Society of Nuclear Cardiology Board of Directors, September 6, 20.  相似文献   
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Dapsone, used for prevention of Pneumocystis jirovecii infections, has been reported to cause hemolytic anemia and methemoglobinemia; its tolerability in solid organ transplant recipients is not well described. We investigated dapsone-related adverse events in patients undergoing solid organ transplantation from 1999 to 2004. Transplant providers identified patients for the investigators who then reviewed the patients' hospital and outpatient records. Sixteen solid organ transplant recipients fit case definitions for dapsone-related hemolytic anemia (n = 11) or methemoglobinemia (n = 5). Median time from event to dapsone discontinuation was 15 days; all patients improved after drug discontinuation. G6PD enzyme activity was normal in all patients whose test results were available. Dapsone may be associated with hemolytic anemia or methemoglobinemia, even with normal G6PD levels. These events are often not promptly recognized, and drug discontinuation is delayed. Dapsone-related hemolytic anemia or methemoglobinemia should be considered in solid organ transplant recipients with unexplained anemia or hypoxia.  相似文献   
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