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941.
942.
943.
Abstract: Drug-induced oesophageal lesions have attracted increasing attention during the past few years. A test model is presented for assessing irritative or ulcerogenic effects of potential drugs on the oesophagus. In this model the pig oesophagus is used, as it is more similar to the human oesophagus than models used in other techniques that have been suggested. The β-blockers, alprenolol and propranolol, displayed the same ulcerogenic properties with this test model as reported with other test models in the literature. The β1-selective blocker metoprolol, did not have such ulcerogenic effects. The pig model is suggested as the method of choice in evaluating the potential irritative or ulcerogenic effects of pharmaceutical formulations intended for human use.  相似文献   
944.
Specimens from the ovarian cortical stroma of 15 postmenopausal women were examined histologically and were incubated for 4 hours in Krebs' bicarbonate buffer containing 5.5 mM glucose and 1% bovine serum albumin. Specimens of normal postmenopausal stroma produced measurable amounts of androstenedione, estradiol, and progesterone in vitro. Specimens with stromal hyperplasia produced larger amounts of androstenedione and estradiol than those with normal stroma. Androstenedione was the predominant steroid produced in both groups. The nonnegligible formation of estradiol indicated an aromatizing capacity of the stromal tissue. The addition of hCG elicited a significant increase in cyclic AMP formation in specimens from ovaries with stromal hyperplasia, indicating a preserved responsiveness to gonadotropin in this type of ovaries.  相似文献   
945.
Two patients with dystrophia myotonica and pleomorphic adenoma of the parotid gland are described. The probability that this coincidence could be due to chance is less than 1 to 1,000 (P less than or equal to 0.001). There are several reports in the literature of the association of myotonic dystrophy with neoplasia. The reason for their association is not understood.  相似文献   
946.
947.
Six dogs were subjected to halothane anaesthesia under hypoxic and non-hypoxic conditions. Plasma fluoride levels in hepatic venous and arterial blood, as well as blood flow to the liver, were measured during anaesthesia. The amount of fluoride released by the liver could thus be calculated. Release of fluoride took place in all animals during non-hypoxic halothane anaesthesia. The amount released varied between the individual animals and in three of them it rose further during hypoxic anaesthesia. The occurrence of defluorination of halothane, even under non-hypoxic conditions, may indicate a reductive metabolism in at least some parts of the liver. The significance of this hypothesis is discussed.  相似文献   
948.
949.
SYNOPSIS
The preventive effect of propranolol on migraine attacks was compared to placebo in a double-blind cross-over trial. Thirty-two patients with serious and prolonged migraine participated in the 12-week study. The effect of propranolol was significantly better than that of placebo. The number of migraine attacks during the propranolol period was reduced in 22 patients (69%), and in 11 of these (34%) a reduction of more than 50% was seen. The intensity of headache was significantly reduced during the propranolol period. The intake of analgesics and preparations containing ergotamine was significantly reduced during the propranolol period also. No serious side effects were noted.  相似文献   
950.
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