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991.
992.
G H Greeley Y S Guo G Gomez F Lluis P Singh J C Thompson 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1988,189(3):325-328
The purpose of this study was to determine whether the inhibitory action of peptide YY (PYY) on gastric acid secretion is attributable to the release of gastric somatostatin in rats. Two groups of rats (six rats/group) were anesthetized with urethane and prepared with gastric fistulas and jugular catheters. Pentagastrin (18 micrograms/kg-h) was given intravenously for 150 min to stimulate gastric acid secretion. Intravenous PYY (130 micrograms/kg-h) inhibited pentagastrin-stimulated gastric acid secretion significantly (P less than 0.05). Administration of iv PYY resulted in a 41% reduction (P less than 0.05) in pentagastrin-stimulated gastric acid secretion. In another group of anesthetized rats, administration of PYY (10(-7), 10(-8) M) failed to stimulate a release of somatostatin from the isolated-perfused rat stomach. Our findings indicate that PYY can inhibit gastric acid secretion independently of release of gastric somatostatin in the rat. 相似文献
993.
J W Osebold Y C Zee L J Gershwin 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1988,188(3):259-264
Inhaled ozone was found to exert an enhancing effect for allergic lung sensitization when mice contracted an aerosolized allergen. The animals were exposed to ozone concentrations of 0.24, 0.16, 0.13, and 0.10 ppm. After 4 days of continuous ozone exposure, the mice had allergen contact from an aerosolized solution of ovalbumin. The animals were then maintained in ambient air for several days before the cycle of ozone and aerosolized allergen was repeated over four allergen contact cycles. Mice were rested in ambient air for a week after the last allergen contact, and they were then tested for allergic sensitization by the intravenous injection of 2 mg of ovalbumin to induce anaphylactic shock in allergic individuals. The control groups of mice were maintained in ambient air throughout the experiment, but they experienced identical allergen contact with the ozone-exposed mice. The phenomenon of allergic enhancement from ozone inhalation was detected at 0.24, 0.16, and 0.13 ppm of ozone. The enhancing effect disappeared at 0.10 ppm of ozone. The study indicated a potential for increasing the number of allergically sensitized individuals when various allergens are inhaled during periods of high ozone exposure with the consequent adverse changes on respiratory membranes. The significance to human health of the allergic enhancement phenomenon by ozone needs investigation. 相似文献
994.
A Yanai I Tange Y Bandoh K Tsuzuki H Sugino S Nagata 《Plastic and reconstructive surgery》1988,82(6):965-972
Our technique for the correction of cryptotia using both Z-plasty and the advancement flap is described. The main advantages are the simple design of the skin incision and the possibility of its application to cryptotia other than severe cartilage deformity and extreme lack of skin. 相似文献
995.
Prefabricated sensate myocutaneous and osteomyocutaneous free flaps: an experimental model. Preliminary report 总被引:1,自引:0,他引:1
Principles of neovascularization have been reported for the successful creation of a variety of muscle and bone free flaps. This study demonstrates a simple and effective technique for construction of prefabricated sensate myocutaneous and osteomyocutaneous free flaps in a rat model. These experiments were carried out in 20 Sprague-Dawley male rats. In half the animals, a sensate myocutaneous flap was constructed by sandwiching the superficial inferior epigastric vessels between a laterally based external abdominal oblique muscle flap and a laterally based skin flap served by an identified cutaneous nerve. A similar preparation included a piece of iliac crest bone. Two to three weeks later, now neovascularized by the sandwiched vessels, the flaps were harvested and transferred as free flaps with high reliability. An increased number of potential donor sites, the versatility of design, and the ability to customize flaps to the specific recipient-site needs are proffered. 相似文献
996.
Metabolism of C26 bile alcohols in the bullfrog, Rana catesbeiana, was studied. [24-14C]-24-Dehydro-26-deoxy-5 beta-ranol (3 alpha,7 alpha,12 alpha-trihydroxy-27-nor-5 beta-cholestan-24-one) was chemically synthesized from [24-14C]cholic acid and incubated with bullfrog liver homogenate fortified with NADPH. 24-Dehydro-26-deoxy-5 beta-ranol was shown to be converted into both 26-deoxy-5 beta-ranol and 24-epi-26-deoxy-5 beta-ranol [(24S)- and (24R)-27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24-tetrols] in addition to 5 beta-ranol [(24R)-27-nor-5 beta-cholestane-3 alpha,7 alpha,12 alpha,24,26-pentol], which is the major bile alcohol of the bullfrog. [24-3H]-26-Deoxy-5 beta-ranol and [24-3H]-24-epi-26-deoxy-5 beta-ranol were prepared from 24-dehydro-26-deoxy-5 beta-ranol by reduction with sodium [3H] borohydride and administered respectively to two each of four bullfrogs by intraperitoneal injection. After 24 h, labeled 5 beta-ranol was isolated from the bile of the bullfrogs that received [24-3H]-26-deoxy-5 beta-ranol. In contrast little if any radioactivity could be detected in 5 beta-ranol or its 24-epimer after administration of [24-3H]-24-epi-26-deoxy-5 beta-ranol. 相似文献
997.
998.
Thermoluminescence dosimetry measurements of gamma rays produced by the atomic bomb in Hiroshima were made by the predose technique using eight ceramic samples collected from five buildings located at distances between 1271 and 2051 m from the hypocenter. The results of our measurements are compared to both the newer dose estimates (Dosimetry System 1986) and older dose estimates (Tentative 1965 Doses) for survivors of the Hiroshima atomic bomb. In comparison with the older estimates, our results are larger by a factor of 2.3 at 1271 m and 3.9 at 2051 m. Our results and the newer estimates for Hiroshima differ by a factor of only 1.14 +/- 0.16 on the average. 相似文献
999.
1000.