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251.
Summary The serum activities of aspartate aminotransferase, alanine aminotransferase, -hydroxybutyrate dehydrogenase and creatine phosphokinase have been measured in the African elephant. In general, the values were broadly comparable with those of man except that alanine aminotransferase was much lower and creatine phosphokinase higher. No variation due to age, sex, season or location was observed. 相似文献
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255.
The DNP fibres gamma-irradiated under aerobic condition showed a reduction of their diameter, while no remarkable changes were observed in the DNP fibres irradiated under hypoxic condition by scanning electron microscopy. 相似文献
256.
T Dalton 《Experientia》1976,32(11):1421-1423
5-Hydroxytryptamine creatinine sulphate loses its biological activity when maintained at room temperature. The loss of 5-HT activity (in stimulating sodium transport across frog skin) is greater than the loss of creatinine sulphate activity (inhibition of sodium transport). 相似文献
257.
Ca2+-stimulated ATPase activity of sarcoplasmic reticulum (SR) preparations is activated after a short period of preincubation at temperatures between 40 and 45 degrees C, but for temperatures higher than 48 degrees C pronounced denaturation is observed. Heat denaturation is decreased if Mg2+ or K+ are present during heat treatment. 相似文献
258.
A. J. Rein D. D. Saperstein S. H. Pines P. C. Radlick 《Cellular and molecular life sciences : CMLS》1976,32(10):1352-1354
Summary Using Raman spectroscopy, we demonstrate that low levels of -carotene, lycopene, and xanthophyll give rise to resonance enhanced bands in blood plasma. These results explain the significance of previously unidentified spectral maxima which have been related to the state of health of the blood donor. 相似文献
259.
H. N. Nigg J. A. Svoboda M. J. Thompson S. R. Dutky J. N. Kaplanis W. E. Robbins 《Cellular and molecular life sciences : CMLS》1976,32(4):438-439
Summary An ecdysone 20-hydroxylase enzyme system that converts -ecdysone to 20-hydroxyecdysone was prepared from the midgut of the tobacco hornworm prepupa. This partially purified enzyme is NADPH dependent and is localized in the mitochondrial fraction of the midgut tissue. 相似文献
260.
Patricia M. Kralik Beng T. Ho H. R. Matthews 《Cellular and molecular life sciences : CMLS》1976,32(6):723-725
Summary
9 (10 mg/kg, i.p.) administered to mice immediately after withdrawal from a 3-day exposure to ethanol vapor was found to intensify withdrawal reactions. No effect was seen when
9 was administered chronically during the exposure to ethanol. 相似文献