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21.
Endogenous tumor necrosis factor exerts its protective function intracellularly against the cytotoxicity of exogenous tumor necrosis factor. 总被引:5,自引:0,他引:5
T Okamoto N Watanabe N Yamauchi Y Tsuji N Tsuji Y Itoh H Neda Y Niitsu 《Cancer research》1992,52(19):5278-5281
Based on the findings that expression of endogenous tumor necrosis factor (enTNF), which is not present in TNF-susceptible cells, was generally observed in TNF-resistant cells and that TNF gene transfection gives rise to TNF resistance, the assumption was made that enTNF may be a protective protein against the cytotoxicity of exogenous TNF. However, it remains unknown whether the protection by enTNF is exerted in an intracellular or extracellular (autocrine) manner. We therefore transfected a nonsecretory human TNF gene (pTNF delta pro) into highly TNF-sensitive mouse tumorigenic fibroblasts (L-M cells) and investigated their TNF susceptibility. The transfectants expressed enTNF which was not secreted into the medium and acquired an appreciable degree of resistance to exogenous TNF. A significant increase in the manganous superoxide dismutase level was also noted in the transfectants. These findings suggest that enTNF exerts its protective function intracellularly by inducing manganous superoxide dismutase production. 相似文献
22.
H Iioka I Moriyama M Kyuma M Akasaki Y Katoh K Itoh M Saitoh K Hino Y Okamura Y Itani 《Nippon Sanka Fujinka Gakkai zasshi》1987,39(5):725-730
The placental transport mechanism of glutathione (GSH) was investigated using microvillous membrane vesicles prepared from human term placenta. Using (3H-glycine)-labeled-GSH, it was clarified that GSH in the extravesicular compartment of placental microvillous membranes was rapidly degraded by gamma-GTP (gamma-glutamyltranspeptidase) and resulting amino acid, and 3H-labeled-glycine was actively transported via a sodium cotransport system. AT-125 treated microvillous membrane vesicles almost entirely lost its gamma-GTP activity, and showed intact GSH transport. Using AT-125 treated microvillous membrane vesicles, it was revealed that GSH was transported across the microvillous membrane as an anion via a membrane potential-dependent mechanism. These results indicated that gamma-GTP which existed in microvillous membrane played a role in GSH metabolism and that intracellular GSH was translocated out of the syncythiotrophoblast cell into the maternal blood space via a specific carrier in microvillous membrane because the GSH concentration was higher in intracellular than extracellular and extracellular membrane potential was positively charged. 相似文献
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During past 30 years, we experienced 253 patients who underwent surgery for myasthenia gravis. Among these patients, 9 were associated with Graves' disease. No patients had thymoma. Five patients underwent thymectomy after they had become euthyroid by medical treatment, though four patients required subtotal thyroidectomy before thymectomy. One patient developed myasthenic crisis following thyroidectomy and was treated with respirator for 5 days. But thymectomy was performed without myasthenic crisis in these four patients between 25 days and 60 days after thyroidectomy. They have been doing well and no see-saw phenomenon was presented. Thymectomy is safe and effective even in the patients with Graves's disease, and we recommend to perform it after they become euthyroid by medical or surgical treatment. 相似文献
26.
T Toukairin-Oda E Sakamoto N Hirose M Mori T Itoh H Tsuge 《Journal of nutritional science and vitaminology》1989,35(3):171-180
Through use of a simplified analyzing system, seven vitamin B6 derivatives were determined with a satisfactory sensitivity and precision. This system consisted of a single reversed-phase ODS column with a fluorescence detector employing an isocratic solvent system. Each vitamin B6 derivative in some foods and biological materials was determined, based on the measurement of the integrated peak area. The data obtained by this method were compared with those obtained from a bioassay by Saccharomyces uvarum ATCC 9080, after acid hydrolysis of these materials. 相似文献
27.
T Urakawa Y Nagahata Y Azumi Y Hashimoto A Itoh K Takeda I Sano Y Saitoh 《Scandinavian journal of gastroenterology》1988,23(6):705-711
We experimentally studied the influence of vagotomy on hepatic regeneration in rats after hepatectomy of cirrhotic livers. In animals that underwent hepatectomy plus vagotomy the reduction in gastric pH was suppressed, but gastric mucosal blood flow was less than that in control animals that received hepatectomy alone. The suppression of 3H-thymidine uptake percentage and thymidine kinase activity after hepatectomy was more marked in animals treated with hepatectomy plus vagotomy than in controls treated with hepatectomy alone. Hepatic DNA level tended to be lower in animals treated with hepatectomy plus vagotomy than in controls. In animals treated with hepatectomy plus vagotomy, the peak level of the mitotic index was lower and the hepatic regeneration rate was evidently suppressed. These results suggest that it is not appropriate to apply vagotomy, during hepatectomy of cirrhotic livers, for the prevention of postoperative stress ulcer because it causes a marked reduction in gastric mucosal blood flow and suppresses hepatic regeneration. 相似文献
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Yasuyuki Shimada Masatoshi Kawata Yasushi Iwasaki Hideshi Itoh Hideyuki Kawachi 《Annals of thoracic and cardiovascular surgery》2004,10(5):304-306
We operated on a patient who had been paraplegic since sustaining a spinal cord injury 11 years ago. We made a reversed L-shaped sternum incision and cannulated all tubes for the cardiopulmonary bypass through a wound window. This provided an excellent surgical view without restricting the patient's upper limbs (needed for wheel chair operation), and recovery was good. Just after surgery, however, it was difficult to control blood pressure and the loss of serum albumin. We believe this is the first report of open-heart surgery undertaken in a paraplegic patient and that the reversed L-shaped incision and careful monitoring of hemodynamics each played an important role in the successful outcome. We hope that this report will help in the treatment of other paraplegic patients who need open-heart surgery. 相似文献
30.
背景:人细小病毒B19(B19)感染表现为多种皮损并与很多其他皮肤病相似,因此难以鉴别。B19感染的病原学诊断通常以费时的血清学试验和多聚酶链式反应(PCR)为依据。目的:本研究中使用一种DN A扩增法———回路介导等温扩增法(LAM P)来诊断B19感染,并与PCR法比较。方法:纳入10例B19 相似文献