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991.
BACKGROUND/AIMS: MELD-Na (model for end-stage liver disease with incorporation of serum sodium) was suggested to provide better survival prediction than MELD alone for patients with end stage liver disease. However, there is no data verifying the usefulness of MELD-Na for predicting short term mortality of cirrhotic patients in Korea. This study was aimed to determine whether MELD-Na would be more accurate in predicting short term mortality than other scoring systems such as Child-Turcotte-Pugh (CTP) or MELD. METHODS: Data from 355 patients admitted due to liver cirrhosis were retrospectively reviewed. The cumulative survival rates were obtained. Prediction of mortality rate for three months and one year were analyzed using the area under the receiver's operating characteristics curve (AUC). RESULTS: One hundred patients (28%) died during the study period. All of the three systems showed significant differences in the cumulative survival rate according to the scores on admission (p0.001). The AUC of CTP, MELD, and MELD-Na in predicting three-months mortality were 0.828, 0.845, and 0.862 (p0.05), and the AUC of each score system for death within one year were 0.792, 0.800, and 0.831, respectively (p0.05). The AUC of MELD-Na in predicting short term death were the highest, although it was not statistically significant. Multivariate analysis showed that only MELD-Na was significantly related to three-month mortality (p=0.012). CONCLUSIONS: MELD-Na is more appropriate in predicting short term mortality, but larger scale studies are needed to confirm the superiority of MELD-Na to MELD and CTP in patients with liver cirrhosis.  相似文献   
992.
BACKGROUND: Although EUS-guided drainage procedures have been used to collect peripancreatic fluids, little is known regarding EUS-guided transmural gallbladder drainage for high-risk patients with acute cholecystitis. OBJECTIVE: Our purpose was to evaluate the technical feasibility and outcomes of EUS-guided transmural cholecystostomy as rescue management in elderly and high-risk patients with acute cholecystitis. DESIGN: Single-center prospective study. SETTING: Tertiary referral center. PATIENTS: Nine elderly or high-risk patients diagnosed with acute cholecystitis. INTERVENTIONS: All inflamed gallbladders were drained by EUS-guided transmural cholecystostomy. MAIN OUTCOME MEASUREMENT: Clinical resolution of acute cholecystitis. RESULTS: After the drainage procedures, there were no immediate complications such as bleeding, bile leak, or peritonitis, except for 1 patient who had pneumoperitoneum. After EUS-guided transmural cholecystostomy, all patients showed rapid clinical improvement within 72 hours. LIMITATIONS: Small number of patients. CONCLUSION: EUS-guided transmural cholecystostomy may be feasible and safe as initial, interim, or even definitive treatment of patients with severe acute cholecystitis who are at high operative risk for immediate cholecystectomy.  相似文献   
993.
Chang BC  Lim SH  Kim DK  Seo JY  Cho SY  Shim WH  Chung N  Kim SS  Cho BK 《The Journal of heart valve disease》2001,10(2):185-194; discussion195
BACKGROUND AND AIM OF THE STUDY: The clinical evaluation and comparison of St. Jude Medical (SJM) and CarboMedics (CM) prosthetic heart valves implanted between 1988 and 1997 is presented. METHODS: In total, 648 SJM valves were implanted in 641 patients, and 601 CM valves in 591 patients. There were 684 mitral valve replacements, 256 aortic valve replacements, 252 mitral and aortic (double) valve replacements, 16 triple valve replacements, and 41 other tricuspid-related valve replacements. Total follow up was 98%. The overall incidence of valve-related events was compared before and after establishment of a 'valve clinic' in 1993. RESULTS: The overall hospital mortality was 3.4%; late mortality was 8.2%. The five- and ten-year survival for all patients was 92.1% and 86.2%, respectively. There were 31 episodes of thromboembolism in 27 patients (including valve thrombosis in three), 21 episodes of bleeding events in 20 patients, and 18 re-replacements of implanted valves. No structural valve deterioration was observed. Freedom from thromboembolism was 97.8% at five years and 96.3% at ten years; freedom from bleeding episodes was 98.1% and 97.6%, respectively. In terms of hospital and late mortality, and incidence of thromboembolism, hemorrhagic episodes and structural valve failure, no statistically significant differences were found between the SJM and CarboMedics patient groups. Freedom from thromboembolism was 96.7% at five years before initiation of an intensive follow up program, and 99.0% thereafter (p = 0.031). In contrast, freedom from bleeding episodes fell from 99.3% to 96.1% during the same time period (p = 0.0004). CONCLUSION: Both the SJM and CM prosthetic heart valves performed well in our study, and no discernible differences in clinical performance of the two valves were detected. The intensive follow up program resulted in a reduced incidence of thromboembolism, but an increased number of bleeding complications. An optimum anticoagulation regimen to manage these two conflicting problems has yet to be elucidated.  相似文献   
994.
BACKGROUND: An ectopic opening of the common bile duct in the duodenal bulb is extremely rare, and the clinical significance of this anomaly has not been clarified. This study analyzed the clinical implications and cholangiographic findings of this anomaly. METHODS: A total of 18 patients (15 men, 3 women; median age, 51 years) with an ectopic opening of the common bile duct in the duodenal bulb were studied. Medical records, endoscopic findings, and cholangiographic and other radiographic findings were reviewed. RESULTS: All 18 patients had biliary pain; 7 had fever and chills. Fifteen (83%) had diffuse dilatation of the extrahepatic bile ducts with or without intrahepatic bile duct dilation. Associated bile duct stones were found in 10 (56%) patients. The papilla in the bulb had an orifice stained with bile at endoscopy, which was associated with duodenal ulcer disease found in 13 (72%) patients. The distal end of the common bile duct was tapered and narrowed and had a hook shape in all patients. CONCLUSION: An ectopic opening of the common bile duct in the duodenal bulb may be associated with clinical entities such as recurrent or intractable duodenal ulcer, choledocholithiasis, or acute cholangitis. Although these openings are rare, knowledge of the endoscopic and radiographic findings of an ectopic opening of the common bile duct in the duodenal bulb may help to clarify the cause of chronic recurrent duodenal ulcer disease in some patients and prevent damage to the bile duct during surgery.  相似文献   
995.
The shortage of donor organs occasionally mandates the use of hepatic allografts from anti-HBc (+) donors. HBIG and/or lamivudine are recommended for the prevention of de novo HBV infection in naive patients, but there are attendant problems, such as mutant strain emergence and high cost. Active immunization presents a better alternative than the use of HBIG or lamivudine, if it can be proven to be effective. Accordingly, we investigated the outcome of HBV vaccination in pediatric hepatic transplant recipients. Between July 1999 and October 2001, 19 pediatric recipients were administered HBV vaccinations after liver transplantation at Seoul National University Hospital. Nine patients received a graft from anti-HBc (+) donors and 10 from anti-HBc (-) donors. When steroid was withdrawn, recombinant HBV vaccine was administered. The median follow-up period after vaccination was 10.0 +/- 5.2 months. Seventeen of the 19 patients showed a positive response to vaccination. In 9 patients who received grafts from anti-HBc (+) donors, 2 patients showed no response, 4 patients low response (peak HBsAb titer <1,000 IU/L), and 3 patients high response (peak HBsAb titer >/=1,000 IU/L). De novo HBV infection developed in 1 of 2 patients who showed no response to vaccination. In 10 patients who received grafts from anti-HBc (-) donors, 5 showed a low response and 5 a high response. In conclusion, HBV vaccination in pediatric patients after liver transplantation appeared to exhibit some effectiveness at protecting young children that received a graft from anti-HBc (+) donors from de novo HBV infection.  相似文献   
996.
Small intestinal primary adenocarcinomas, carcinoids, gastrointestinal stromal tumors (GISTs) were cleared up inadequately because it was hard to examine for small intestine by modalities in the 20th century. Obscure gastrointestinal bleeding (OGIB) is often caused by these tumors. In future, these tumors will be more diagnosed in patients with OGIB by new modalities such as capsule endoscopy and double balloon endoscopy. We attempt to present these small intestinal malignant tumors using by capsule endoscopy and double balloon endoscopy.  相似文献   
997.
Catalytic methane steam reforming was conducted at low temperature using a Pd catalyst supported on Ce1−xMxO2 (x = 0 or 0.1, M = Ca, Ba, La, Y or Al) oxides with or without an electric field (EF). The effects of the catalyst support on catalytic activity and surface proton hopping were investigated. Results show that Pd/Al-CeO2 (Pd/Ce0.9Al0.1O2) showed higher activity than Pd/CeO2 with EF, although their activity was identical without EF. Thermogravimetry revealed a larger amount of H2O adsorbed onto Pd/Al-CeO2 than onto Pd/CeO2, so Al doping to CeO2 contributes to greater H2O adsorption. Furthermore, electrochemical conduction measurements of Pd/Al-CeO2 revealed a larger contribution of surface proton hopping than that for Pd/CeO2. This promotes the surface proton conductivity and catalytic activity during EF application.

Temperature dependence of electron/ion conductivity of Pd/CeO2 and Pd/Al-CeO2 under wet conditions with application of an electric field.  相似文献   
998.
When synthesizing nanoparticles in the liquid phase, polymeric materials (mainly polyvinylpyrrolidone, PVP) are applied as capping and/or stabilizing agents. The polymer layer on the nanoparticles must likely be removed since it blocks the active sites of the catalyst and inhibits mass transfer of the reactants. However, we have found that the polymer can have a positive effect on the direct synthesis of hydrogen peroxide. By testing Pd/SiO2 catalysts with different amounts of PVP, it was revealed that an adequate amount of PVP resulted in a higher rate of hydrogen peroxide production (1001 mmolH2O2 gPd−1 h−1) than pristine Pd/SiO2 did (750 mmolH2O2 gPd−1 h−1), unlike other PVP added Pd/SiO2 catalysts containing excess PVP (less than 652 mmolH2O2 gPd−1 h−1). The effect of PVP on the catalysts was examined by transmission electron microscopy, Fourier transform infrared spectroscopy, CO chemisorption, thermogravimetric analysis, and X-ray photoelectron spectroscopy. For the catalysts containing PVP, the oxidation state of the palladium 3d shifted to high binding energy due to electron transfer from Pd to the PVP molecules. Consequently, the presence of PVP on the catalysts inhibited oxygen dissociation and decomposition of the produced hydrogen peroxide, resulting in a high selectivity and high production rate of hydrogen peroxide.

Addition of polyvinylpyrrolidone to Pd/SiO2 catalyst improved H2O2 selectivity by adjusting electronic state of palladium active species.  相似文献   
999.

Purpose

Accurate assessment of viability of hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE) is important for therapy planning. The purpose of this study is to determine the diagnostic value of a novel image analysis method called parametric response mapping (PRM) in predicting viability of tumor in HCC treated with TACE for dynamic CT images.

Methods

35 patients who had 35 iodized-oil defect areas (IODAs) in HCCs treated with TACE were included in our study. These patients were divided into two groups, one group with viable tumors (n = 22) and the other group with non-viable tumors (n = 13) in the IODA. All patients were followed up using triple-phase dynamic CT after the treatment. We compared (a) manual analysis, (b) using PRM results, and (c) using PRM results with automatic classifier to distinguish between two tumor groups based on dynamic CT images from two longitudinal exams. Two radiologists performed the manual analysis. The PRM approach was implemented using prototype software. We adopted an off-the-shelf k nearest neighbor (kNN) classifier and leave-one-out cross-validation for the third approach. The area under the curve (AUC) values were compared for three approaches.

Results

Manual analysis yielded AUC of 0.74, using PRM results yielded AUC of 0.84, and using PRM results with an automatic classifier yielded AUC of 0.87.

Conclusions

We improved upon the standard manual analysis approach by adopting a novel image analysis method of PRM combined with an automatic classifier.  相似文献   
1000.

Purpose

Quality of life (QoL) and performance status predict survival in advanced cancer patients; these relationships have not been explored in the hospice palliative care setting. The aim of this study was to examine the survival predictability of patient-reported QoL using the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C15-PAL questionnaire in far advanced cancer inpatients at the very end of life.

Methods

This is a retrospective cohort study. Patients reported QoL using the EORTC QLQ-C15-PAL. One hundred sixty-two inpatients in hospice palliative wards of six hospitals in South Korea were followed until death or the end of the study. Additional symptoms and performance status were assessed by the MD Anderson Symptom Inventory—Korean (MDASI-K), Palliative Performance Scale (PPS) and Eastern Cooperative Oncology Group (ECOG) performance status. Correlations between EORTC QLQ-C15-PAL, MDASI-K, PPS, and ECOG were assessed. Survival analyses were performed using Cox proportional hazard models.

Results

Patients’ median survival was less than 1 month. Physician-reported PPS significantly predicted survival (hazard ratio [HR] 0.493; p?<?0.001). From the EORTC QLQ-C15-PAL, patient-reported physical functioning predicted survival (HR?=?0.65; p?<?0.001). Other six domains of EORTC QLQ-C15-PAL were significantly related to survival after adjustment. Those domains were global health status, emotional functioning, fatigue, nausea/vomiting, appetite loss, and constipation.

Conclusions

EORTC QLQ-C15-PAL can be an independent prognostic factor in inpatients with far advanced cancer. Patient-reported physical functioning showed survival predictability as good as physician-reported performance status. It is notable that the QLQ instrument is useful even for patients in their final month of life. Cancer anorexia–cachexia syndrome-related symptoms may be independent prognostic symptoms. Prospective study is warranted.  相似文献   
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