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781.
782.
B-HT 920, a selective agonist at dopamine (DA) autoreceptors, strongly increased the incidence of penile erections (PE) in male rats, an effect which was dose-related and antagonized by haloperidol. B-HT 920 at 100 and 200 micrograms/kg i.p. significantly altered the copulatory pattern of sexually active male rats, reducing the number of mounts and intromissions as well as the latency to the first ejaculation, a stimulant effect which was confirmed in sluggish males at a dose of 100 micrograms/kg. 相似文献
783.
Summary Poison oak urushiol, a mixture of 3-alk(en)ylcatechol derivatives was found to mediate DNA strand scission in the presence of oxygen and with copper(II) chloride as a catalyst. The reactionis believed to occur via activated reduced oxygen produced during oxidation of the catechol into itso-quinone derivative. 相似文献
784.
785.
786.
Arsenite but not oxamate produce in vitro a distinct depression of estrogen-dominated uterine motility, both in the absence of substrate as well as in the presence of exogenous glucose or lactate. The addition of oxamate to preparations suspended in a medium with lactate as the sole external substrate ameliorates the depression of uterine motility elicited by arsenic. 相似文献
787.
The present study deals with the dissociation of human dopamine beta hydroxylase (DBH) in subunits with a mol. wt of 79,500, and the preparation of specific antibodies in rabbits. No cross-reactivity was observed between human DBH and antibodies against human DBH subunits. 相似文献
788.
789.
The molecular mechanism by which insulin stimulates glycogen synthesis in mammalian skeletal muscle 总被引:37,自引:0,他引:37
The ability of insulin to promote the phosphorylation of some proteins and the dephosphorylation of others is paradoxical. An insulin-stimulated protein kinase is shown to activate the type-1 protein phosphatase that controls glycogen metabolism, by phosphorylating its regulatory subunit at a specific serine. Furthermore, the phosphorylation of this residue is stimulated by insulin in vivo. Increased and decreased phosphorylation of proteins by insulin can therefore be explained through the same basic underlying mechanism. 相似文献
790.
Identification of angiogenic activity and the cloning and expression of platelet-derived endothelial cell growth factor 总被引:55,自引:0,他引:55
F Ishikawa K Miyazono U Hellman H Drexler C Wernstedt K Hagiwara K Usuki F Takaku W Risau C H Heldin 《Nature》1989,338(6216):557-562
Cloning and sequencing of the complementary DNA for platelet-derived endothelial cell growth factor indicates that it is a novel factor distinct from previously characterized proteins. The factor, a protein with a relative molecular mass of about 45,000, stimulates endothelial cell growth and chemotaxis in vitro and angiogenesis in vivo. 相似文献