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991.
AIMS: This study aimed to analyse the current outcome after palliative surgical drainage of malignant biliary obstruction. METHOD: From 1992 to 2003, perioperative parameters and the incidence and indications of readmissions were analysed in 269 patients who underwent a palliative biliary bypass for periampullary carcinoma. RESULTS: Hospital mortality occurred in seven patients and median postoperative stay was 10 days. Anastomotic leakage occurred in three patients and intraabdominal haemorrhage in eight patients. Overall 75 patients experienced a complication. Nine patients underwent a relaparotomy during initial hospital admission. Overall, 142 patients were readmitted, 13 for indications related to the biliary bypass, 11 for surgery-related indications. Twenty-five patients were readmitted for radiochemotherapy, 112 for progressive disease and 23 for indications not related to the disease. Median survival was 7.5 months and the 3-year survival 3%. Survival was significantly lower in patients with metastases and in those who underwent elective bypass for gastric outlet obstruction. CONCLUSION: Current hospital mortality after palliative biliary bypass as well as readmission rates for complications related to the biliary bypass or surgical procedure are low. Surgical biliary bypass is a safe and effective palliative treatment for patients with malignant biliary obstruction.  相似文献   
992.
Des-tyrosine-gamma-endorphin (DT gamma E), a derivative of gamma-endorphin, which has been reported to have some neuroleptic-like properties in man, was administered to eight hospitalized schizophrenic patients (six chronic, one subacute, one acute) in an open study. Following an initial drug-free period, patients were given DT gamma E for 12 days in doses ranging from 1 to 10 mg/day. Two of the patients were markedly improved after receiving DT gamma E. The improvement was sustained for 2 months in one subjects, while the other deteriorated to pretreatment status within 48 hours of the discontinuation of DT gamma E. Of the other six patients, one showed moderate improvement, three showed minimal improvement, and two showed no change. Improvement was mainly in the area of social functioning; change in positive psychotic symptoms was less noticeable. The positive results obtained in this study in some subjects could have been nonspecific effects, rather than pharmacological action, since social functioning, the main area of improvement, may be especially sensitive to expectancy effects in open trials. Nevertheless, further study of DT gamma E in acute schizophrenics for longer periods appears indicated.  相似文献   
993.
Immunohistochemistry (IHC) in clinical practice is hampered by lack of standardization and by subjectivity in interpretation and quantitation. This study aimed to develop a control system for IHC in routinely fixed and histoprocessed tissues. Such a system should be easy to handle in clinical practice and should reflect variations in fixation time, section thickness, section storage conditions, and staining protocols. In addition, in image analysis quantitation of immunostained tissues, when using classifiers computed on IHC-control images, the control system should be very stable. Cultured human fibroblasts were suspended in agarose, transferred into a length of tubing and stored at 4 degrees C. Three pieces of the cellgel control were separately fixed, histoprocessed, and paraffin-embedded as external controls. One piece was prepared together with each of 18 bladder carcinoma biopsies as internal controls. Slides with sections from the biopsy and all types of cellgel controls were stored at different temperatures and then stained using three different IHC protocols. The fibroblasts were homogeneously distributed in the agarose gel. Variation in section thickness did not influence immunostaining as evaluated by the MIB1 labelling index (MIB1 LI). The external controls decreased notably in MIB1 LI with increased fixation time. This was not seen in the 18 internal controls that were each fixed with a fresh biopsy. However, section storage and immunostaining conditions influenced the MIB1 expression equally in all control types and to a similar degree to the biopsies. Furthermore, colour-based image analysis quantitation of MIB1 LI in biopsies proved stable and independent of the control type used to compute the classifier.  相似文献   
994.
995.
The chromosomal translocation t(8;14) is the hallmark of Burkitt's-lymphoma (BL) and fuses the proto-oncogene c-MYC to the IGH locus. We analyzed the genomic structure of MYC/IGH fusions derived from a large series of 78 patients with t(8;14) and asked (i) whether distinct breakpoint clusters exist within the MYC gene and (ii) whether any pairwise association between particular IGH and MYC breakpoints exist. Identification of such associations will help elucidate the etiology of the breaks on the MYC locus. Scan statistic analyses revealed two distinct, but large clusters within c-MYC containing 60/78 (77%) of the breakpoints. Clusters 1 and 2 were 560 and 779 bp in length within a 4555 bp breakpoint cluster region. Breaks within IGH switch mu and joining region did not differ with respect to their corresponding MYC breakpoints. However, there was a highly significant correlation between breakpoints 5' of MYC cluster 1 and fusions to IGH switch gamma region and breakpoints downstream of MYC cluster 2 and fusions to IGH switch alpha region (chi(2)-test: P<0.005). Chromatin changes governing choice of IGH-Fc region recombination may parallel changes in the MYC gene 5' region chromatin leading to some degree of coordinated ontological specificity in breakpoint location.  相似文献   
996.
OBJECTIVE: To compare endoscopic and surgical drainage of the pancreatic duct for ductal decompression in patients with severe pain due to chronic pancreatitis and a dilated pancreatic duct. DESIGN: Randomized clinical trial. METHOD: All symptomatic patients with chronic pancreatitis and a distal obstruction of the pancreatic duct, but without an inflammatory mass, were eligible for this study. Patients were randomized to endoscopic transampullary pancreatic duct drainage or to operative pancreaticojejunostomy. The primary end point was the average Izbicki pain score, measured during 2 years of follow-up. The secondary endpoints were pain relief at the end of follow-up, physical and mental health, morbidity, mortality, hospital stay and number of procedures performed. RESULTS: Of 118 patients who were evaluated between January 2000-October 2004 39 patients were randomized; 19 were treated endoscopically (16 of whom underwent lithotripsy) and 20 by operative pancreaticojejunostomy. During 24 months of follow-up, compared with endoscopic drainage, surgery was associated with lower Izbicki pain scores (51 versus 25; p < 0.001) and better SF-36 physical health summary scores (p = 0.003). Furthermore, at the end of follow-up, pain relief was achieved in 32% of patients randomized to endoscopic drainage and 75% of patients randomized to surgical drainage (p = 0.007). Complication rates and hospital stay were similar, but endoscopic treatment required more procedures (median 8 versus 3; p < 0.001).  相似文献   
997.
OBJECTIVE: To measure HIV-1 quasispecies diversity in very recently infected male and female plasma donors. METHODS: HIV-1 RNA testing of blood and plasma donations was used to select anti HIV-1 antibody negative, HIV-1 RNA positive plasma samples from 13 males and four females undergoing primary infection. To determine whether these early viral populations were clonal or oligoclonal, heteroduplex mobility assays were performed on multiple independently generated envelope PCR products. Genetically heterogeneous quasispecies where subcloned and their divergent envelope variants sequenced. RESULTS: Because of frequent plasma donations in this population, HIV-1 RNA quasispecies could be studied during very early primary infection. Heteroduplex mobility assays detected the presence of genetically distinct variants in four of the 17 plasma donors. DNA sequence analysis showed that one case was due to a G to A hyper-mutation event and that two cases were caused by the presence of in-frame insertions/deletions resulting in DNA heteroduplex mobility shifts. The early plasma quasispecies of one female contained highly divergent variants differing by up to 6% substitution and multiple insertions/deletions, a level of divergence unlikely to have been generated de novo following transmission. V3 loop sequences analysis indicated the presence of non-syncitium inducing genotypes in 14 out of 17 primary infection cases. CONCLUSION: Plasma viremia is generally genetically homogeneous even during the very early phase of primary infection when viremia is first detected and still rising exponentially. Evidence for the transmission of multiple variants was detected in only one out of four women and none of 13 men undergoing primary infection with subtype B HIV-1.  相似文献   
998.
Incidence and management of biliary leakage after hepaticojejunostomy   总被引:5,自引:2,他引:3  
This study analyzes the change in the management of biliary leakage after hepaticojejunostomy. Between 1993 and 2003 all patients (n = 1033) were studied with a hepaticojejunostomy as part of a pancreatoduodenectomy (n = 486), proximal bile duct resection (without liver resection) (n = 35), and biliodigestive bypass for malignant (n = 302) and benign (n = 210) disease. Biliary leakage was defined as the presence of bile-stained fluid (>50 mL) in the abdominal drain more than 24 hours after surgery, proven radiologically or at relaparotomy. The studied patients were divided into two equal periods to analyze the change in management. Overall, 24 of 1033 patients (2.3%) had biliary leakage. In multivariate analysis, a body mass index greater than 35 kg/m2 (P = .012), endoscopic biliary drainage (P = .044), and an anastomosis on the segmental bile ducts (P < .001) were independent predictors of leakage. Management in the first half of the study period (1993-1998) versus the second half (1999–2003) was maintenance of operatively placed drains (18% vs. 15%, respectively, P = 1.000), percutaneous transhepatic biliary drainage (18% vs. 69%, respectively, P = .012), surgical drainage (55% vs. 8%, respectively, P = .023), and re-hepaticojejunostomy (9% vs. 8%, respectively, P = 1.000). There was no mortality in the patients with biliary leakage. Leakage after a hepaticojejunostomy is a relatively rare complication without mortality and can safely be managed with percutaneous transhepatic biliary drainage. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation).  相似文献   
999.
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