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21.
Primary omental leiomyosarcomas are rare intra-abdominal tumours. A few cases only have been reported in the literature. We present a case of a 79-year old woman, whose tumour was surgically removed. We include a hort review of the literature.  相似文献   
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Summary The anticancer activity of carminomycin was investigated in a human tumor cloning assay. No efficacy could be identified in the WiDr and the MCF7 cell lines which were highly responsive to doxorubicin. In addition, drug testing experiments were carried out in samples of various malignancies freshly obtained from 86 patients of whom 54 had not received prior anthracyclines. A reduction in the number of tumor colony forming units by 50% or more was seen in 1/26 breast cancers, 1/22 ovarian cancers and 1/7 melanomas. Cross-resistance studies indicated that eight tumors were responsive to doxorubicin only and one to carminomycin only whereas two were sensitive to both and 73 were resistant to both. This in vitro Phase II study corroborates the disappointing clinical results achieved with carminomycin.  相似文献   
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delta 3-7 alpha-Phenylacetamidodesacetoxycephalosporanic acid was prepared by ring expansion of 6-epi-benzylpenicillin-S-sulfoxide, using N,O-bis(trimethylsilyl)acetamide (BSA) as silylating and dehydrating agent and alpha-picoline/alpha-picoline hydrobromide as catalyst. In some experiments 7 alpha-phenylacetamido-3 beta-bromo-3 alpha-methylcepham-4 alpha-carboxylic acid was obtained as a side product. 7-Epimers in the desacetoxycephalosporanic series were also prepared by base-catalyzed epimerization of the benzyl 7 beta-(p-nitrobenzylideneimino)desacetoxycephalosporanate and of the S-sulfoxide of natural methyl 6-phenylacetamidodesacetoxycephalosporanate. In both reactions 1,5-diazabicyclo(4.3.0)non-5-ene (DBN) was used as epimerization catalyst.  相似文献   
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In order to evaluate the incidence and risk factors of infection by hepatitis C virus (HCV) among injecting drug users (IDUs), we conducted a prospective cohort study of HCV- and human immunodeficiency virus (HIV)-negative IDUs in the North and East of France. A total of 231 HCV and HIV IDUs who had injected drugs at least once in their lifetime were followed up every 3 months over a 12-month period. Serum anti-HCV and anti-HIV were tested at inclusion in the study and at the end of the follow-up. Data on injecting practices were collected at inclusion and at each visit. Of the 231 participants included, 165 (71.4%) underwent a final HCV and HIV serum test. The incidence was nil for HIV infection and 9/100 person-years (95% CI 4.6-13.4) for HCV infection. In a multivariable analysis, we found that syringe and cotton sharing were the only independent predictive factors of HCV seroconversion.  相似文献   
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Consumption of concentrated barley beta-glucan lowers plasma cholesterol because of its soluble dietary fiber nature. The role of molecular weight (MW) in lowering serum cholesterol is not well established. Prior studies showed that enzymatic degradation of beta-glucan eliminates the cholesterol-lowering activity; however, these studies did not evaluate the MW of the beta-glucan. The current study was conducted to evaluate whether barley beta-glucan concentrates, partially hydrolyzed to reduce MW, possess cholesterol-lowering and antiatherogenic activities. The reduced MW fraction was compared with a high MW beta-glucan concentrate from the same barley flour. Concentrated beta-glucan preparations were evaluated in Syrian Golden F(1)B hamsters fed a hypercholesterolemic diet (HCD) with cholesterol, hydrogenated coconut oil, and cellulose. After 2 wk, hamsters were fed HCD or diets that contained high or reduced MW beta-glucan at a concentration of 8 g/100 g at the expense of cellulose. Decreases in plasma total cholesterol (TC) and non-HDL-cholesterol (non-HDL-C) concentrations occurred in the hamsters fed reduced MW and high MW beta-glucan diets. Plasma HDL-C concentrations did not differ. HCD-fed hamsters had higher plasma triglyceride concentrations. Liver TC, free cholesterol, and cholesterol ester concentrations did not differ. Aortic cholesterol ester concentrations were lower in the reduced MW beta-glucan-fed hamsters. Consumption of either high or reduced MW beta-glucan increased concentrations of fecal total neutral sterols and coprostanol, a cholesterol derivative. Fecal excretion of cholesterol was greater than in HCD-fed hamsters only in those fed the reduced MW beta-glucan. Study results demonstrate that the cholesterol-lowering activity of barley beta-glucan may occur at both lower and higher MW.  相似文献   
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