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111.
H. Goldman R. Fischer N. Nicolov S. Murphy 《Cellular and molecular life sciences : CMLS》1975,31(3):328-330
Zusammenfassung Die i.v. Verabreichung von LSD an Ratten steigert den Blutkreislauf im Hirnstamm sowie im frontalen und parietalen Cortex selektiv. Es wurden durch 6-Nor-LSD, 2-Methyl-LSD und
8, 9-LSD weder wahrnehmbare Verhaltensänderungen noch Änderungen des regionalen Blutkreislaufs verursacht. 相似文献
112.
By comparing the melting temperature of DNA-DNA duplexes between related species, it is shown that total single-copy DNA evolves at a faster rate that DNA which is transcribed into poly (A)-containing RNA. Such a comparison suggests that at least 70% of rat single-copy DNA does not code for protein. 相似文献
113.
Summary The crucial functional groups of phorbol-12-myristate-13-acetate (PMA) are superimposable with those of the glucocorticoid cortisol in a unique manner which suggests a mechanism for PMA activity, i.e. the alkylation of a cortisol receptor. 相似文献
114.
115.
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
116.
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
117.
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
118.
119.
The non-steroidal ecdysone agonist RH-5849 (1,2-dibenzoyl-l-tert-butylhydrazine) was found to be an effective neurotoxicant on injection into the American bird grasshopper,Schistocerca americana (Drury). Treated grasshoppers became immediately hyperactive, followed by loss of coordination, paralysis and eventually death. We also discovered that this compound induced bilateral autotomy of the metathoracic legs during the early stages of intoxication. However, no evidence of ecdysonergic or morphogenetic activities was observed. Synergism studies with neurotoxins of known mode of action suggested that RH-5849 has a mechanism of action similar to that of 4-amino pyridine, which blocks potassium channels. 相似文献
120.
Antioxidant survey to assess antagonism to redox stress using a prokaryotic and an eukaryotic system
H. Baker B. DeAngelis O. Frank M. Khalil S. H. Hutner E. R. Baker 《Cellular and molecular life sciences : CMLS》1996,52(6):597-599
Using a prokaryote (Escherichia coli) and a metazoa-resembling eukaryote (Ochromonas danica), we surveyed antioxidants which might overcome redox stress imposed by menadione sodium bisulphite (MD) and buthionine sulphoximine (BSO). BSO oxidant stress was evident only inO. danica; MD oxidant stress was evident in both organisms. Glutathione, its precursors, e.g. cysteine, homocysteine, and 2-oxo-4-thiazolidine carboxylic acid, and red blood cells, emerged as prime antioxidants for relieving BSO and MD oxidant stress. BSO and MD oxidant activity and antioxidant-annulling effect inO. danica were judged comparable to those found in animal cells whereas the resultsE. coli were not entirely equivalent. TheO. danica system emerged as a practical, rapid, and useful system for pinpointing oxidant stressors and antioxidants, and shows promise for studies with mammalian systems. 相似文献