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81.
PURPOSE Early-stage colon cancer patients (Dukes A or B; pT1–T3 pNO pMO) are excluded from adjuvant chemotherapy following potentially curative surgery because they are expected to have good long-term survival. However, 20 percent to 30 percent of these patients ultimately succumb from recurrent disease. This indicates that the conventional staging procedures may be unable to precisely predict cancer prognosis.METHODS In 65 early-stage colon cancers, we investigated by immunohistochemistry the role of molecular markers such as p27, p53, and vascular endothelial growth factor in identifying high-risk patients who may benefit from adjuvant treatments.RESULTS No clinicopathologic factor, namely Dukes stage, t parameter, number of resected nodes, and vascular or lymphatic invasion, was found be an independent significant predictor of disease-specific and disease-free survival. In contrast, each molecular marker predicted survival and recurrence rates much better than the conventional Dukes staging system. The best combination of variables for prediction of long-term outcome and recurrence rate included p27, p53, and vascular endothelial growth factor. Interestingly, the greater the number of molecular alterations, the lower the five-year estimated survival function. Nearly all cancer-related deaths were observed among patients whose colon cancers expressed all three molecular alterations. Regardless of Dukes stage, the recurrence rate was found to increase with the increase in the number of molecular alterations. Early-stage colon cancers expressing p27 down-regulation and high p53 and vascular endothelial growth factor immunoreactivity showed a 100 percent actuarial four-year recurrence rate.CONCLUSIONS Assessment of molecular alterations may be useful to identify a higher-risk group of early-stage colon cancer patients who may benefit from adjuvant chemotherapy.  相似文献   
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BACKGROUND: The pathogenesis of alcoholic pancreatitis may involve the metabolism of ethanol (via oxidative and non-oxidative pathways) within the pancreas. The aims of this study were to determine the rate of non-oxidative metabolism in isolated rat pancreatic acini and to compare this to the rate of ethanol oxidation. METHODS: Pancreatic acini were isolated from male Sprague-Dawley rats and incubated with (14)C-ethanol. Radiolabelled fatty acid ethyl esters (non-oxidative metabolites) were isolated from lipid extracts by thin-layer chromatography. Radiolabelled acetate (oxidative metabolite) was isolated from the incubation medium by ion-exchange chromatography. RESULTS: Non-oxidative metabolism by isolated pancreatic acini was demonstrated. At 50 and 100 mmol/l ethanol, fatty acid ethyl ester concentrations were 49.6 +/- 13.3 and 199 +/- 93 micromol/l, respectively. These levels have previously been shown to result in tissue injury. Non-oxidative metabolism was increased 9-fold by addition of oleic acid and inhibited by the lipase inhibitor, tetrahydrolipstatin, by 91.05 +/- 1.99%. The rate of oxidative metabolism was 21-fold higher than that of non-oxidative metabolism. CONCLUSIONS: Intact pancreatic cells metabolize ethanol by the non-oxidative pathway, generating fatty acid ethyl esters at a rate sufficient to cause pancreatic damage. Oxidative metabolism of ethanol occurs at a much higher rate and may also play a role in pancreatitis.  相似文献   
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Time- and dose-dependent changes in plasma catecholamines, heart rate, and blood pressure were studied in response to sublethal doses of intravenous (i.v.) bacterial endotoxin in conscious male rats. Hypotension occurred with high endotoxin (1,000 micrograms/kg), whereas hypertension occurred in the low-dose group (10 micrograms/kg). All groups had significant tachycardia, which was dose and time dependent, but heart rate was unchanged for the first 2 hr in the low-dose groups (100 and 10 micrograms/kg). Plasma levels of norepinephrine (NE) and epinephrine (E) increased with both dose and time and there was significant interaction of dose and time effects. NE levels increased maximally at 0.5 hr following the highest dose of endotoxin and remained elevated during the protocol. Plasma E levels were maximal at 0.5 hr in the high-dose group, but then declined while remaining significantly higher than the 10 and 100 micrograms/kg endotoxin-treated groups for the duration of the protocol. Peak E levels in the 100 and 10 micrograms/kg group occurred at 3.0 hr and then decreased at the 6.0 hr time. Significant increases in plasma catecholamines and heart rate with endotoxin in the absence of significant hypotension present the possibility that factors other than blood pressure may be mediating efferent sympathetic outflow in endotoxicosis.  相似文献   
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The use of thumbtacks in massive presacral bleeding   总被引:4,自引:0,他引:4  
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BACKGROUND/AIMS: Helicobacter pylori (H. pylori) infection is one of the most common gastrointestinal diseases. An increasing number of people undergo different treatment options. Unfortunately, H. pylori therapy may be troublesome for drug side effects and inefficacious for resistance to antibiotics. METHODOLOGY: One hundred and ninety-three (193) H. pylori-positive patients were randomly assigned to one of the following 7-day treatments: Group A (N = 64): amoxicillin, clarithromycin and rabeprazole; Group B (N = 64): tinidazole, clarithromycin and ranitidine bismuth citrate; Group C (N = 65): tinidazole, clarithromycin and rabeprazole Eradication was assessed by 13C-Urea Breath Test 6-8 weeks after the end of the therapy. Not-eradicated patients underwent a second cycle with tinidazole, tetracycline, bismuth and rabeprazole. All patients were asked to complete a validated questionnaire regarding presence and intensity of drug side effects. RESULTS: One hundred and eighty-eight out of the 193 H. pylori-positive patients (96%) completed therapy. No significant difference in eradication rates was observed among the three groups both in intention to treat analysis and in per protocol analysis. No significant difference in incidence of side effects occurred among groups after the first-line regimens: 48% in group A, 44% in group B and 46% in group C. Twenty-two out of the 193 enrolled subjects (11%) were not eradicated after the first-line therapy. Among them, 86% were successfully eradicated by the tinidazole, tetracycline, bismuth and rabeprazole therapy. Moreover, during quadruple therapy, a higher prevalence and intensity of side effects than in each one of the groups submitted to the first-line triple therapy was observed. CONCLUSIONS: This study shows that triple rabeprazole-based eradicating regimens are effective and safe. Incidence of side effects seems low and similar in different three-drug regimens used. Quadruple therapy, which appear highly efficacious as a second line therapy, is associated with a significantly higher incidence of side effects when compared to first-line treatment.  相似文献   
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BACKGROUND/AIMS: The outcome of endoscopic biliary stent insertion for postoperative bile duct stenosis was retrospectively evaluated. METHODOLOGY: Fifty-seven patients with biliary stenosis from laparoscopic cholecystectomy were included from February 1992 to January 2000. One to three stents were inserted for an average of 12.4 months, with stent exchange every 3 months to avoid cholangitis caused by clogging. RESULTS: Successful stent insertion was achieved in 43/57 (75.4%) patients. Stent insertion failed in 10 patients with complete and in 4 patients with incomplete biliary obstruction. Early complications occurred in 4 patients. Late complications occurred in 5/43 patients. Five patients experienced recurrence of stenosis. CONCLUSIONS: Endoscopic treatment should be the initial management of choice for postoperative bile duct stenosis.  相似文献   
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