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71.
From 1968 to 1984, 250 patients with cirrhosis and bleeding esophageal varices underwent portal disconnection of the esophagus using either Murphy's button (before 1974) or an esophageal device developed by one of the authors (after 1974). One hundred and thirty-four patients underwent operation on an elective basis and 116 underwent emergency procedures. With the use of Child's classification, 62 patients were class A, 125 were class B and 63, class C. The over-all operative mortality rate was 24.4 per cent but this varied with the hepatic functional status and whether or not the operation was done on an elective or emergency basis. The long term survival rates were 53 per cent at one year, 36 per cent at three years, 24 per cent at five years and 8 per cent at ten years. Ninety-six per cent of the patients were without proved recurrent esophageal bleeding at one year, 88 per cent at three years, 79 per cent at five years and 66 per cent at ten years. Portal disconnection of the esophagus using an anastomotic button is a simple and effective procedure which can benefit many patients with cirrhosis who undergo an operation for bleeding varices on an elective or emergency basis. It constitutes an efficacious prophylactic means for preventing recurrent bleeding from esophageal varices.  相似文献   
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AIMS: To obtain pharmacokinetic data for artesunate (ARTS) and its active metabolite dihydroartemisinin (DHA) following i.m. ARTS and rectal DHA administration. METHODS: Twelve Vietnamese patients with uncomplicated falciparum malaria were randomized to receive either i.v. or i.m. ARTS (120 mg), with the alternative preparation given 8 h later in an open crossover design. A further 12 patients were given i.v. ARTS (120 mg) at 0 h and rectal DHA (160 mg) 8 h later. RESULTS: Following i.v. bolus, ARTS had a peak concentration of 42 microm (16 mg l(-1), elimination t1/2 = 3.2 min, CL = 2.8 l h(-1) kg(-1) and V = 0.22 l kg(-1) . The Cmax for DHA was 9.7 microm (2.7 mg l(-1) ), t1/2 = 59 min, CL = 0.64 l h(-1) kg(-1) and V = 0.8 l kg(-1) . Following i.m. ARTS, Cmax was 2.3 microm (3.7 mg l(-1)), the apparent t1/2 = 41 min, CL = 2.9 l h(-1) kg(-1) and V = 2.6 l kg(-1). The relative bioavailability of DHA was 88%, Cmax was 4.1 microm (1.16 mg l(-1)) and t1/2 = 64 min. In the rectal DHA study, relative bioavailability of DHA was 16%. CONCLUSIONS: For patients with uncomplicated falciparum malaria i.m. ARTS is a suitable alternative to i.v. ARTS, at equal doses. To achieve plasma DHA concentrations equivalent to parenteral administration of ARTS, rectal DHA should be given at approximately four-fold higher milligram doses. Further studies are needed to determine whether these recommendations can be applied to patients with severe malaria.  相似文献   
74.
Gimm O  Niederle BE  Weber T  Bockhorn M  Ukkat J  Brauckhoff M  Thanh PN  Frilling A  Klar E  Niederle B  Dralle H 《Surgery》2002,132(6):952-9; discussion 959
BACKGROUND: In patients with multiple endocrine neoplasia type 2A syndrome, prophylactic thyroidectomy is generally recommended at the age of 5 to 6 years. Whether this recommendation is justified for exon 13 mutations is unknown. METHODS: We analyzed the clinical data from 40 patients harboring RET codon 790/791 mutations (exon 13) who had been treated in 4 specialized centers. RESULTS: Mean age was 35.2 +/- 21.6 years (range, 5.1-69.0 years). Thirteen patients were index patients (mean age, 57.7 +/- 11.3 years), 27 patients were screening patients (mean age, 24.4 +/- 16.5 years). In the index group, pT-category was: T0, n = 2; T1, n = 6; T2, n = 2; T3, n = 1; and T4, n = 2. Lymph node metastases were found in 5 patients and distant metastases in 1 patient. Postoperatively, 69% of index patients were biochemically cured. In the screening group, pT-category was: T0, n = 19; T1, n = 7; and T2, n = 1. Lymph node metastases were found in 2 patients. Postoperatively, 93% of screening patients were biochemically cured. The youngest patient with medullary thyroid carcinoma was 13.8 years, the youngest patient with lymph node metastases was 46.4 years. CONCLUSIONS: Patients with RET codon 790/791 mutations seemed to have a less aggressive clinical course compared with patients with classic multiple endocrine neoplasia type 2A syndrome. Still, index patients had a lower biochemic cure rate in comparison with screening patients. Timely total thyroidectomy including lymph node dissection is warranted.  相似文献   
75.
Antioxidant drugs have been reported to protect pancreatic islets from the adverse effects of chronic exposure to supraphysiological glucose concentrations. However, glucose has not been shown to increase intracellular oxidant load in islets, nor have the effects of increasing or inhibiting glutathione peroxidase (GPx) activity on islet resistance to sugar-induced oxidant stress been studied. We observed that high glucose concentrations increased intracellular peroxide levels in human islets and the pancreatic beta cell line, HIT-T15. Inhibition of gamma-glutamylcysteine synthetase (gammaGCS) by buthionine sulfoximine augmented the increase in islet peroxide and decrease in insulin mRNA levels, content, and secretion in islets and HIT-T15 cells induced by ribose. Adenoviral overexpression of GPx increased GPx activity and protected islets against adverse effects of ribose. These results demonstrate that glucose and ribose increase islet peroxide accumulation and that the adverse consequences of ribose-induced oxidative stress on insulin mRNA, content, and secretion can be augmented by a glutathione synthesis inhibitor and prevented by increasing islet GPx activity. These observations support the hypothesis that oxidative stress is one mechanism for glucose toxicity in pancreatic islets.  相似文献   
76.
BACKGROUND: The Program on the Surgical Control of the Hyperlipidemias (POSCH), a secondary intervention trial, was the only lipid/atherosclerosis randomized clinical trial that used a surgical modality--partial ileal bypass. POSCH provided solid evidence for the clinical and arteriographic benefits of lipid profile normalization. Few longterm followup reports have been published in this field. This report concerns overall mortality, the primary endpoint of POSCH, with a mean followup of 18 years (range 15.5 to 23.0 years). STUDY DESIGN: Overall mortality data were compiled from reports to the POSCH clinics, followup telephone calls, death certificates, and the US National Death Index. RESULTS: There were 144 deaths in the control group (n = 417) and 120 deaths in the intervention group (n = 421), using intent-to-treat analysis. The risk reduction in the intervention group was 0.201 (20%); the risk ratio was 0.799, or 0.8 (95% confidence intervals, 0.628 to 1.018, p = 0.07). The proportion of patients alive was 65.7% in the control group and 72.0% in the intervention group, for a difference of 6.3% in the intervention group (p = 0.05). Kaplan-Meier survival analysis (p = 0.046) and disease-free intervals analysis at 70% survival (p < 0.001) were confirmatory. The gain in life expectancy in the intervention group was 2.7 years. CONCLUSIONS: Longterm followup POSCH data demonstrate that lipid profile normalization will decrease overall mortality and will maintain a persistent and constant increase in life expectancy.  相似文献   
77.
Adult patients with acute lymphoblastic leukemia (ALL) and t(1;19)/E2A-PBX1 or t(4;11)/MLL-AF4 have a poor outcome. We have evaluated the impact of an intensified post-remission therapy using a high-dose chemotherapy course followed by allogeneic or autologous SCT on the outcome of 58 patients with t(1;19)/E2A-PBX1 (E2A group, n=24) or t(4;11)/MLL-AF4 (MLL group, n=34) treated in the LALA-94 multicenter prospective study. Patients in the MLL group had higher WBC counts and more frequent DIC. CR rates achieved by MLL and E2A groups were similar to other B-cell ALL (87, 82 and 86% respectively). While in CR, patients with a donor were assigned to alloSCT (n=22), the remaining patients with were randomized between autoSCT (n=15) or chemotherapy (n=8). Five-year overall survival was 31 and 45% for E2A and MLL groups, respectively. In both groups, DFS was higher in the alloSCT arm as compared to autoSCT and chemotherapy arms. The results of this study show that chemotherapy intensification did not overcome the poor prognosis of adults with t(1;19)/E2A-PBX1. Allogeneic SCT should thus be offered in first CR to patients with t(1;19)/E2A-PBX1 or t(4;11)/MLL-AF4. New therapeutic approaches are needed for patients without donor.  相似文献   
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Chitinolytic activities in Trichomonas vaginalis membrane extracts were assessed by assays of three enzyme systems: N-acetyl-beta-D-hexosaminidase (NAHase), chitobiosidase and chitotriosidase. N-acetyl-beta-D-hexosaminidase was the enzyme that showed the highest specific activity. After successive subcutaneous inoculations into mice and parasite recovery in culture, the enzyme activities increased significantly with the number of inoculations for up to eight passages. In addition, enzyme activities were maximum at the logarithmic phase of growth. Glycol chitin, a chitinase substrate, enhanced all chitinolytic activities by about 30% and a clear-cut correlation is shown between the capacity for erythrocyte lysis by parasites and NAHase expression. Chitobiosidase and chitotriosidase activities were both inhibited at 58% and 100%, respectively, by allosamidine, a chitinase inhibitor used at 3 microM, whereas NAHase activity was not affected. Seven putative NAHase inhibitors (compounds n, 1-7), ureido and thioureido derivatives of 2-amino-2-deoxy-D-glucose were evaluated and five of them had K(i) values in the range 30-70 microM. The most active compound (compound 6) was functionally competitive with respect to the substrate with a K(i) value of 30 microM. The IC(50) values of the most active compounds on T. vaginalis were in the range 62-85 microM. These results indicate that chitinases of T. vaginalis are involved in pathogenicity and they could be an interesting target for drugs since chitinase inhibitors also inhibit parasite growth.  相似文献   
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