[The use of the deuterated internal standard for morphine quantitation for the purpose of doping control by gas chromatography with mass-selective detection].

The objective of this study was to demonstrate the possibility to use deuterated compounds as internal standards for the quantitative analysis of morphine by gas chromatography with mass-selective detection for the purpose of doping control. The paper is focused on the problems associated with the use of deuterated morphine-D3 as the internal standard. Quantitative characteristics of the calibration dependence thus documented are presented along with uncertainty values obtained in the measurements with the use of deuterated morphine-D6.

[Frequency of chromosome aberrations induced by a single exposure to stress in rats selected for excitability of the nervous system].

The effect of short-term emotional and algesic stress on chromosomal aberration rate in bone marrow cells was studied in four lines of rats selected for excitability of the nervous system. The exposure induced an increase in chromosomal aberration rate only in highly excitable animals; the effect was classified as a low mutagenic. Possible mechanisms of the effect of stress factors on the chromosomal apparatus of cells are discussed.

[The effect of acute hypoxia on the cytogenetic effect of cyclophosphamide in rat bone marrow cells, differing in resistance to oxygen deficiency].

The frequency of chromosomal aberrations in rat bone marrow cells injected with intraperitoneal cyclophosphamide (CF) during the 24 h after acute hypoxia was studied. We used two groups of rats: a group with low resistance (LR) to acute hypoxia that was unable to endure more than 5 min in a vacuum chamber at the altitude of 11,000 m, and a group of highly resistant (HR) rats able to endure 25 min or longer under the above conditions in vacuum chamber. Acute hypoxia was shown to enhance the cytogenetic activity of cyclophosphamide, and the number of chromosomal aberrations was higher in HR rats than in LR animals.

[Frequency of chromosome aberrations induced by stress and cyclophosphane in bone marrow cells of rats selected for the threshold of nervous system excitability].

The frequency of chromosomal aberrations in bone marrow cells under the effect of long-term stress and cyclophosphamide was studied in rat lines selected for different levels of nervous system excitability. After both kinds of treatment, differences between lines in frequencies of chromosomal aberrations were observed. Stress had a weak mutagenic effect on rats with a low level of excitability, but no such effect on highly excitable rats.

[Frequency of chromosome aberrations induced by hypoxia in cells of the rat bone marrow differing in resistance to this trait].

The frequency of hypoxia induced chromosome aberrations in bone marrow cells of rats was researched. According to the resistance to acute hypoxia 2 groups from the population of the laboratory animals were singled out. One of the groups is low resistant animals capable of being at "the height" 11 thousand metres during 5 minutes, the other group is high resistant animals capable of being in the state of acute hypoxia during 25 minutes and even longer.