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251.
252.
P. Pani A. Sanna M. I. Brigaglia A. Columbano L. Congiu 《Cellular and molecular life sciences : CMLS》1976,32(11):1449-1451
Summary Acute toxicity induced by DMN was partially prevented by previously administering methyl mercuric chloride (MMC), a chemical inhibitor of the drug metabolizing enzyme system (DMES). We have studied the early changes occurring during the course of DMN-intoxication, namely disaggregation of polysomal profiles and necrosis, evaluated morphologically and by the release of S-GPT.This work was supported by Consiglio Nazionale delle Ricerche, Roma, Italy. 相似文献
253.
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
254.
255.
Possible role for cyclic nucleotides and phosphorylated membrane proteins in postsynaptic actions of neurotransmitters. 总被引:2,自引:0,他引:2
P Greengard 《Nature》1976,260(5547):101-108
The postsynaptic actions of some neurotransmitters may be mediated through cyclic nucleotides and cyclic nucleotide-dependent phosphorylation of specific membrane proteins in postsynaptic cells. In addition to providing a molecular basis for the actions of several neurotransmitters and of certain drugs affecting behaviour, the model suggests a mechanism by which neurotransmitter signals may be converted into electrophysiological responses in postsynaptic cells. 相似文献
256.
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
257.
The hyperthermic effect of a bacterial pyrogen has been studied in rabbits pretreated or not with p-chlorophenylalanine or 5, 6-dihydroxytryptamine. The results obtained indicate that a selective reduction of cerebral 5-hydroxytryptamine levels by these drugs do not significantly affect pyrogen hypertermia. 相似文献
258.
V. R. Osório E Castro M. G. P. Vale A. P. Carvalho 《Cellular and molecular life sciences : CMLS》1976,32(4):424-426
Summary The effect of the antibiotic X-537A on the phosphorylated ATPase (EP) was investigated. The results show that X-537A depresses the level of EP which is dependent on the Ca2+ gradient, while the Ca2+-independent EP is not affected.
Acknowledgments. This work was supported by grants from the Instituto de Alta Cultura of the Portuguese Ministry of Education (No. CB/2) and the Calouste Gulbenkian Foundation. 相似文献
259.
G. M. Hanozet M. Simonetta D. Barisio A. Guerritore 《Cellular and molecular life sciences : CMLS》1976,32(10):1246-1249
Summary The three enzymes of ethanol metabolism alcohol dehydrogenase, aldehyde dehydrogenase and acetyl-CoA synthetase in the obligate aerobic yeastRhodotorula gracilis are repressed by glucose and induced by C2 metabolic fuels with a regulatory pattern indicating a correlation in the control mechanisms. To try an identification of the molecular signals involved in the transmission of the inducing stimulus, experiments were carried out by blocking with 2 mM pyrazole the ethanol acetaldehyde metabolic step. Results indicate that ethanol is not specifically required as a molecular signal for induction.This work was supported by a grant from the Italian Consiglio Nazionale delle Ricerche. 相似文献
260.
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