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951.
Multiple thyroid adenomas formed by straight or coiled epithelial cords developed in experiments on adult male rats as a result of prolonged intermittent 6-MTU administration. Such epithelial cords could be sometimes observed in thyroid parenchyma regeneration after partial thyroidectomy. These cords originated from thyrocytes of the follicle epithelium. In the proliferating thyroid parenchyma DNA replication mainly terminated in endomitoses (previously reported data) which in thyrocytes of prismatic form resulted in their separation from proximal and distal daughter cells. Proximal daughter cells kept contact with the follicle lumen but distal ones lost it, hence their iodine uptake and origination weakened. Therefore, the biosynthesis of thyroglobulin decreased in cytoplasm of distal daughter cells but the formation of thyroalbumin increased. In consequence the distal daughter cells with this shift in protein biosynthesis underwent hypertrophy and further originated the proliferation of extra follicular epithelial cords. The formation of new follicles mainly took place with the differentiation of interfollicular islets separated from proliferating extrafollicular epithelial cords. Thyrotropin, the principal stimulator of hormonopoietic thyrocyte activity, did not necessarily influence the activation of thyroid parenchyma proliferative processes.  相似文献   
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An experience with the treatment of 106 patients with pyloroduodenal stenosis of ulcerous etiology by vagotomy with draining operations has shown high efficiency of these measures resulting in lower rate of postoperative lethality. Selective proximal and stem vagotomy does not aggravate gastric atony in patients with stenosis. Electro-stimulation was found to be an effective method of treatment of this complication in the postoperative period of patients with gastric atony.  相似文献   
955.
Thyroid function tests were performed on 16 clinically euthyroid patients with end-stage renal failure undergoing regular haemodialysis or continuous ambulatory peritoneal dialysis and compared with 8 healthy subjects. The patient groups were carefully matched, especially regarding relative duration of dialysis (mean of 24 months). Total serum thyroxine, total triiodothyronine, free thyroxine, free triiodothyronine and reverse triiodothyronine were significantly lower in both patient groups than control. The thyrothrophin response to the standard thyrotrophin-releasing hormone test was delayed and blunted. Using a novel concentration technique we measured loss of T4 in peritoneal dialysate effluent and found it to be approximately 10% of daily thyroidal T4 release.  相似文献   
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The chemopreventive efficacy of 11 organosulfur compounds was assessed using the murine nuclear aberration (NA) assay in C57BL/6J mice. The sulfur compounds were introduced by stomach gavage. Benzo[a]pyrene (BP), which is a carcinogen known to a) undergo biotransformation by pathways mediated by P-450 and b) induce NA in the intestine, was used as the challenge. All animals were killed 48 hours after BP injection, and NA per crypt were scored. The results indicated that several agents were active in inhibiting BP nucleotoxicity to the colon, most notably, allyl mercaptan, benzyl mercaptan, and phenylethyl mercaptan. The NA assay was useful in effectively prescreening certain compounds for potential interactions with chemical carcinogens, thus serving as one indicator of chemopreventive activity.  相似文献   
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