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Washout of autacoids using a repeated change of serosal Ringer solution of the frog urinary bladder was accompanied by a pronounced rise in the osmotic water permeability. A decrease in the osmotic water permeability was achieved by addition at the serosal Ringer solution of different eikosanoids at concentrations of 10(-10)-10(-6) M. According to efficiency of the recovery of the low osmotic water permeability, the substances studied showed the following order: prostaglandin E1 > prostaglandin > E2 > prostaglandin F2 alpha > (prostaglandin I2). The data obtained indicate a role of the endogenous prostaglandin production in maintaining of the low osmotic water permeability. 相似文献
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G. E. Mitchell W. I. Furman E. V. Lychagin A. Yu. Muzichka G. V. Nekhaev A. V. Strelkov E. I. Sharapov V. N. Shvetsov Yu. I. Chernuhin B. G. Levakov V. I. Litvin A. E. Lyzhin E. P. Magda B. E. Crawford S. L. Stephenson C. R. Howell W Tornow 《Journal of research of the National Institute of Standards and Technology》2005,110(3):225-230
Although crucial for resolving the issue of charge symmetry in the nuclear force, direct measurement of nn-scattering by colliding free neutrons has never been performed. At present the Russian pulsed reactor YAGUAR is the best neutron source for performing such a measurement. It has a through channel where the neutron moderator is installed. The neutrons are counted by a neutron detector located 12 m from the reactor. In preliminary experiments an instantaneous value of 1.1 × 1018/cm2s was obtained for the thermal neutron flux density. The experiment will be performed by the DIANNA Collaboration as International Science & Technology Center (ISTC) project No. 2286. 相似文献
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EI Levy AM Scarrow E Kanal G Rubin H Yonas L Kirby 《Canadian Metallurgical Quarterly》1998,19(10):1943-1946
Intraarterial thrombolytic therapy decreases mortality in the treatment of acute basilar artery occlusion. An acute decrease in cerebral blood flow (CBF) (<12 mL/100 g per minute) has been reported to invariably result in infarction. We report a case of acute basilar artery occlusion, recanalized within 90 minutes, with reversal of CBF of less than 6 mL/100 g per minute. After reperfusion, areas with persistent CBF of 6 mL/100 g per minute resulted in infarctions on subsequent CT studies. Parenchymal viability is possible after 90 minutes of posterior CBF of 6 mL/100 g per minute. 相似文献
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EI Korpelainen MJ Karkkainen A Tenhunen M Lakso H Rauvala M Vierula M Parvinen K Alitalo 《Canadian Metallurgical Quarterly》1998,143(6):1705-1712
Vascular endothelial growth factor (VEGF) is a key regulator of endothelial growth and permeability. However, VEGF may also target nonendothelial cells, as VEGF receptors and responsiveness have been detected for example in monocytes, and high concentrations of VEGF have been reported in human semen. In this work we present evidence that overexpression of VEGF in the testis and epididymis of transgenic mice under the mouse mammary tumor virus (MMTV) LTR promoter causes infertility. The testes of the transgenic mice exhibited spermatogenic arrest and increased capillary density. The ductus epididymidis was dilated, containing areas of epithelial hyperplasia. The number of subepithelial capillaries in the epididymis was also increased and these vessels were highly permeable as judged by the detection of extravasated fibrinogen products. Intriguingly, the expression of VEGF receptor-1 (VEGFR-1) was detected in certain spermatogenic cells in addition to vascular endothelium, and both VEGFR-1 and VEGFR-2 were also found in the Leydig cells of the testis. The infertility of the MMTV-VEGF male mice could thus result from VEGF acting on both endothelial and nonendothelial cells of the male genital tract. Taken together, these findings suggest that the VEGF transgene has nonendothelial target cells in the testis and that VEGF may regulate male fertility. 相似文献
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EI Burtseva AN Slepushkin AL Beliaev LV Kolobukhina LN Merkulova VV Boltenko AI Stepnova NA Beregovski? LG Rudenko 《Canadian Metallurgical Quarterly》1998,(4):40-45
The paper describes a clinical case of the cerebral hyperperfusion syndrome, a rare complication of carotid endarterectomy. The syndrome appeared as the generalized convulsive syndrome in the patient in the early postoperative period. In the context of clinical observation, the results of analysis of the literature are presented and the pathogenesis, diagnosis, therapy, and prevention of the cerebral hyperperfusion syndrome considered. 相似文献
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