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991.
Absorption of vitamin E in children with biliary obstruction   总被引:1,自引:0,他引:1       下载免费PDF全文
J. T. Harries  D. P. R. Muller 《Gut》1971,12(7):579-584
Serum vitamin E levels and red cell haemolysis were measured in 17 children with biliary obstruction after oral and intramuscular loading tests, and during long-term oral administration of differing doses of a fat-soluble and water-miscible preparation of alpha-tocopheryl acetate. The results suggested a severe defect in the intestinal absorption of both preparations. In three of the children who were studied during periods of improving biliary obstruction, absorption was shown to have improved. Bile plays a major role in the absorption of vitamin E from the intestinal tract and the exact mechanism of its action requires further elucidation.  相似文献   
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994.
To assess the molybdenum supply and requirements of preterm infants, Mo concentration was determined in milk from mothers of 6 term and 11 preterm newborns; no difference was found between fore- and hindmilk and no diurnal variations were found during 24-h collections. Respective values (means +/- SD) of term and preterm milks were 10.2 +/- 3.7 and 4.0 +/- 3.7 micrograms/L (106.2 +/- 38.5 and 41.7 +/- 38.5 nmol/L) at 3-5 d of lactation, 4.8 +/- 3.9 and 3.7 +/- 3.8 micrograms/L (50.0 +/- 4.6 and 38.5 +/- 39.6 nmol/L) at 7-10 d, 1.5 +/- 1.4 and 1.4 +/- 0.9 micrograms/L (15.6 +/- 14.6 and 14.6 +/- 9.6 nmol/L) at 14 d, 2.6 +/- 2.2 and 1.9 +/- 1.4 micrograms/L (27.1 +/- 22.9 and 19.8 +/- 14.6 nmol/L) at 1 mo, and 0.2 and 1.2 +/- 0.5 micrograms/L (2.1 and 12.5 +/- 5.2 nmol/L) at 2 mo. A statistical difference was found between term and preterm milk at 3-5 d of lactation. During lactation significant changes were found between the periods 3-5 d and 7-10 d, 14 d, 1 mo (p less than 0.01) and 2 mo (p less than 0.05) of lactation and between 7-10 d and 14 d (p less than 0.05). According to the requirements of the preterm infant, a supplementation of 2-3 micrograms.kg-1.d-1 by enteral route is suggested.  相似文献   
995.
Timliness and equity of access   总被引:1,自引:1,他引:0       下载免费PDF全文
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It is known that a single dose of a neuroleptic can elicit dopaminergic supersensitivity in animals. On the other hand, the clinical syndrome of tardive dyskinesia takes many months or years to develop. To resolve this apparent discrepancy, it is possible that subclinical or latent tardive dyskinesia is fully compensated in most patients taking neuroleptics. In others, where the tardive dyskinesia is full-blown and grossly apparent, the dopaminergic supersensitivity may be decompensated. Such compensatory and decompensatory phases have been proposed earlier by Hornykiewicz (1974), in the case of Parkinson's Disease.Dopaminergic supersensivity persists for a period proportional to the length of the neuroleptic treatment. It is not yet clear whether the relation between the length of treatment and the persistence of supersensitivity holds for very long treatments but in principle the relationship might account for the persistence of tardive dyskinesia after years of neuroleptic pretreatment.  相似文献   
998.
Nifedipine, a calcium channel blocking agent, has been shown safe and effective in the treatment of various cardiac disorders. In Prinzmetal's variant angina, nifedipine relieves the acute spasm of a large coronary artery, and thereby reverses the sudden decrease in myocardial oxygen supply. In chronic stable angina, the efficacy of nifedipine stems from an interplay of direct and reflex effects. A decrease in systemic vascular resistance, and thus, in myocardial oxygen demand, is considered the most important effect. Although this is partially offset by baroreceptor-mediated reflex increases in blood pressure and heart rate, the net effect is a decrease in myocardial oxygen consumption. The importance of nifedipine-induced increases in coronary blood flow in relieving stable angina remains controversial. Numerous clinical trials in patients with chronic angina have demonstrated that nifedipine increases exercise tolerance by lowering the heart rate-blood pressure product (an approximation of myocardial oxygen consumption). The maximal double product during exercise, however, does not increase, suggesting that the drug does not importantly improve myocardial oxygen supply. Nifedipine may also be of value in the therapy of unstable angina, acute myocardial infarction, and hypertension, as well as in the protection of the myocardium at risk during open heart surgery. However, definite recommendations on the use of the drug for these indications must await results of ongoing randomized studies. The effects of nifedipine are dose-related. Larger doses have been shown more effective than smaller doses, as long as an appropriate blood pressure is maintained. The side effects of nifedipine are mild and related to its vasodilating action.  相似文献   
999.
The usefulness of Arfonad-induced controlled hypotension in the management of severe hemorrhagic shock is demonstrated in a patient with a ruptured abdominal aneurysm. Operative treatment had to be delayed for twenty-two hours during which time the systolic blood pressure was maintained artificially at 70 to 90 mm Hg with an intravenous Arfonad drip. No further signs of bleeding were seen and adequate organ perfusion was maintained as evidenced by the absence of renal and cardiac complications thereafter.  相似文献   
1000.
Peer review     
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