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A E Kaliuzhny? E S Platonov O V Mironova G T Sukhikh 《Biulleten' eksperimental'no? biologii i meditsiny》1989,108(11):622-624
Opioid peptide DAGO, agonist of opiate mu-receptors and naloxone antagonist of mu-, delta- and kappa-receptors in concentration 3 x 10 M inhibit embryonic development of CBA mice. Inhibition was stage-specific with maximal effect after addition of opioids to zygotes: in the presence of Naloxone no more than 6.7% of embryos reached morula and blastula stages and in the presence of DAGO--36.8%. The other embryos were arrested at two-, four- or, sometimes even, at eight-cell stages without any signs of fragmentation. Four and eight-cell embryos were less sensitive to drug action. Inhibitory effects of these opioids were reduced when they were added simultaneously to zygotes. Agonist of opiate delta-receptors, opioid peptide DADLe, failed to affect embryonic development. 相似文献
997.
O. van Tellingen H. R. van der Woude J. H. Beijnen C. J. T. van Beers W. J. Nooyen 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1989,488(2)
A high-performance liquid chromatographic method for the determination of N5-methyltetrahydrofolic acid, leucovorin, methotrexate and 7-hydroxymethotrexate in plasma and liquor samples is presented. Gradient elution is used to increase the sensitivity. Four sample preparation methods were compared with respect to the stability of the injectable sample. Samples can be pretreated with a simple deproteinization method. For enhanced selectivity a solid-phase extraction procedure is described. 相似文献
998.
The electrogenic action of the basic amino acid, l-arginine, has been compared with the action of the neutral amino acids, l-alanine and glycine, in mouse pancreatic acinar cells. All three amino acids cause membrane depolarization, but while the reversal potential for the action of the neutral amino acids is close to the calculated value of the Na equilibrium potential (+30 m V) the reversal potential for the l-arginine effects is +7 m V. The neutral amino acids exhibit mutual inhibition, but l-arginine did not inhibit the l-alanine-or glycine-evoked depolarization nor did the neutral amino acids inhibit the action of l-arginine. While l-alanine markedly depressed acetylcholine-evoked depolarization, l-arginine had no such effect. It is concluded that there are at least two quite different types of electrogenic amino acid action in pancreatic acinar cells. 相似文献
999.
L L Klimenko L V Kozlov L P Kudriashova O V Protasova I A Maksimova M N Komarova A A Konradov A A Turna E L Soiustova G N Matveev 《Biofizika》1999,44(1):128-131
The activity of serum complement proteins and the level of steady brain potential in patients with systemic lupus erythematosus and rheumatoid arthritis were determined. The statistical analysis indicated that there is a correlation between the parameters of the complement system and neurophysiological characteristics. The differences between rheumatoid arthritis and systemic lupus erythematosus are observed in the mean values of activity of complement proteins and the steady potential, their dispersions, and the structure of correlations between immunological and neurophysiological parameters. 相似文献
1000.