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G C Randall 《Journal of developmental physiology》1988,10(1):77-83
The role of cortisol as a factor controlling the deposition of glycogen in the pig fetus was examined by infusing either a low dose (1 mg/day) or a high dose (3 mg/day) of cortisol into chronically-catheterized hypophysectomized fetal pigs for five days beginning on day 100-104 of gestation. After infusion, liver glycogen was significantly higher (P less than 0.05) and lung glycogen significantly lower (P less than 0.05) than in uninfused hypophysectomized litter mates although concentrations were significantly different from intact litter mates (P less than 0.05). Although skeletal and cardiac muscle content increased after infusion this difference was not significant. Changes in tissue glycogen content were similar for both the low and high rates of infusion. These observations indicate that exogenous cortisol alone is able to stimulate liver glycogen deposition and reverse the effect of hypophysectomy. Although other factors may be necessary for maximal response this suggests that cortisol is an important stimulant for liver glycogen deposition in the fetal pig. The effect of cortisol on muscle glycogen was equivocal suggesting that other hormones may play a more important role in this tissue. 相似文献
966.
Paracoenia fumosalis Cresson previously known only from the USA and Canada is recorded in the Palaearctic Region for the first time. The adults were collected near a thermal hydrosulfuric spring in the Geiser Valley in Kamchatka. A key to species of the genus Paracoenia occurring in Russia is given. 相似文献
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968.
Fossil plants of the Chingandzha flora were studied from volcanogenic sediments of the Chingandzha and Rond formations on
the northern coast of the Sea of Okhotsk. It was concluded that all platanaceous leaves earlier described in this flora as
different taxa belong to one highly variable species, Pseudoprotophyllum cordatum Samyl. emend. Shczepetov et Golovneva. 相似文献
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