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The relationship between brain and liver damage in chronic alcoholic patients. 总被引:1,自引:1,他引:0 下载免费PDF全文
W Acker E J Aps S K Majumdar G K Shaw A D Thomson 《Journal of neurology, neurosurgery, and psychiatry》1982,45(11):984-987
CT scan measures of topographical brain changes, liver status as determined by biopsy, and clinical factors were studied in a group of detoxified chronic alcoholic patients. It was found that greater topographical brain changes were associated with greater severity of liver disease. 相似文献
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CHANGES IN CHROMOSOMES OF BONE MARROW AFTER INTRAVENOUS INJECTIONS OF 7,12-DIMETHYLBENZ(A)ANTHRACENE AND RELATED COMPOUNDS 总被引:2,自引:0,他引:2 下载免费PDF全文
E. Douglas Rees S. K. Majumdar Amy Shuck 《Proceedings of the National Academy of Sciences of the United States of America》1970,66(4):1228-1235
Multiple intravenous injections of an emulsion containing 7,12-dimethylbenz(a)anthracene (DMBA) or 7,8,12-trimethylbenz(a)anthracene (TMBA) induce a high incidence of leukemia in rats. Twenty-four hours after a single injection, about half of the metaphase cells in the marrow have chromosomes with breaks. Although breaks were inflicted on chromosomes of various sizes and morphology, these aberrations were nonrandom in that members of the nos. 1 and 2 chromosome pairs were involved to an extent greater than expected on the basis of their size and number. Distinctive karyotypic abnormalities involving the no. 2 chromosome were observed in half of the leukemic rats, whereas these abnormalities were not observed in nonleukemic, DMBA-treated rats. Benzo(a)pyrene and benzo(e)pyrene, polycyclic aromatic hydrocarbons which did not induce leukemia, produced fewer breaks of the no. 2 (and other) chromosomes than did DMBA or TMBA. 相似文献
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OBJECTIVE: To systematically review the evidence for the prevention of type 2 diabetes by pharmacological therapies. RESEARCH DESIGN AND METHODS: Randomized controlled trials and cohort studies examining the effect of oral hypoglycemic agents, antiobesity agents, antihypertensive agents, statins, fibrates, and estrogen on the incidence of type 2 diabetes were identified from MEDLINE, EMBASE, the Cochrane Controlled Trials Registry, and searches of reference lists. Two reviewers independently assessed studies for inclusion and performed data extraction. RESULTS: Ten studies of oral hypoglycemic agents and 15 studies of nonoral hypoglycemic agents were found. Oral hypoglycemic agents and orlistat are the only drugs that have been studied in randomized controlled trials with diabetes incidence as the primary end point. In the largest studies of 2.5-4.0 years' duration, metformin (relative risk [RR] 0.69, 95% CI 0.57-0.83), acarbose (0.75, 0.63-0.90), troglitazone (0.45, 0.25-0.83), and orlistat (hazard ratio [HR] 0.63, 95% CI 0.46-0.86) have all been shown to decrease diabetes incidence compared with placebo; however, follow-up rates varied from 43 to 96%. Current evidence for statins, fibrates, antihypertensive agents, and estrogen is inconclusive. In addition, the critical question of whether drugs are preventing, or simply delaying, onset of diabetes remains unresolved. CONCLUSIONS: Currently, no single agent can be definitively recommended for diabetes prevention. Future studies should be designed with diabetes incidence as the primary outcome and should be of sufficient duration to differentiate between genuine diabetes prevention as opposed to simple delay or masking of this condition. 相似文献
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Effect of 5-hydroxytryptamine on protein synthesis in gastrointestinal and other tissues and on serum gastrin concentrations in rats. 下载免费PDF全文
1 The effect of 5-hydroxytryptamine (5-HT) on protein synthesis in the gastrointestinal tissues as well as in the liver, heart and brain was studied by measuring [3H]-leucine incorporation into total tissue protein in vivo in rats. 2 A single injection of 5-HT (10 mg/kg) produced a marked inhibition (45 to 65%) in protein synthesis in the stomach (oxyntic gland area), intestine (jejunum + ileum), colon and brain, but not in the liver and heart. 3 Dose- and time-dependent studies of 5-HT-induced changes in protein synthesis in the stomach of fed rats revealed that the maximal inhibition of about 65% occurred 1 h after a dose of 12.5 mg/kg. 4 Animals deprived of food for 24 h differed from their fed counterparts only in the degree of responsiveness, in that a greater inhibition (75%) of [3H]-leucine incorporation into total protein of the stomach was observed 30 min after 5-HT injection. 5 Pretreatment of animals with methysergide (0.25 mg/kg) essentially abolished the 5-HT-mediated inhibition of protein synthesis in the stomach. 6 Serum gastrin concentration in fasted animals remained slightly elevated during the initial period of 5-HT treatment (up to 1 h). 7 The results demonstrate that in certain tissues, 5-HT markedly inhibits protein synthesis. The inhibition in protein synthesis in the gastrointestinal tract cannot be attributed to changes in the concentration of gastrin. 相似文献