Characteristic Features of Ultrafine-Grained Ti-45 wt.% Nb Alloy under High Cycle Fatigue.

The paper presents the results of fatigue-testing ultrafine-grained and coarse-grained Ti-45 wt.% Nb alloy samples under very high cycle fatigue (gigacycle regime), with the stress ratio R = -1. The ultrafine-grained (UFG) structure in the investigated alloy was formed by the two-stage SPD method, which included multidirectional forging (abc-forging) and multipass rolling in grooved rollers, with further recrystallization annealing.

[An experimental study of anti-amnestic activity of piracetam in orchidectomized rats].

The decrease of learning ability by 50% as assessed by passive avoidance test and the increase 28% of microviscosity of synaptosomal membranes from brain cortex were observed in rats in a month after orchidectomy as compared with that of intact or sham--operated animals. The treatment of orchidectomized rats with piracetam either by single application or in the course of 10 days applications in the daily dose of 250 mg/kg intraperitoneally failed to improve learning ability of animals in passive avoidance test and to produce a normalizing effect on the structure of membrane lipid matrix. The testosterone content in blood of orchidectomized rats was 10 times lower as compared with control and was not affected by treatment with piracetam.

[Effect of piracetam on rat reproductive function and the sexual development of their progeny].

Administration of piracetam to infantile rats in a daily dose of 100 mg/kg for 10 days caused acceleration of sexual maturation of females and a slight delay of maturation of males. Antenatal administration of the same dose of piracetam exerted a depressive action on the development of the organs of the reproductive system in males from the offspring with a simultaneous increase in the pituitary gonadotropic activity.