Complex phase dynamics in coupled bursters.

The phenomenon of phase multistability in the synchronization of two coupled oscillatory systems typically arises when the systems individually display complex wave forms associated, for instance, with the presence of subharmonic components. Alternatively, phase multistability can be caused by variations of the phase velocity along the orbit of the individual oscillator. Focusing on the mechanisms underlying the appearance of phase multistability, the paper examines a variety of phase-locked patterns in the bursting behavior of a model of coupled pancreatic cells.

[The use of oxidant-antioxidant system indices in forming groups at high genetic risk].

While studying the pathogenetic mechanisms of Down syndrome, the imbalance of oxidant-antioxidant system in donors of extrachromosome 21 was detected. This fact was a basis for screening of new prenatal biochemical markers of Down syndrome. The ratio of free radical processes intensity and SOD activity was found as most informative index reflecting the state of oxidant-antioxidant system.

[The biochemical marker dynamics of the maternal serum in different chromosomal disorders of the fetus].

The reasons for false-positive results of Down syndrome screening have been analysed. It has been found that the family pericentric inversions of chromosome 9 in fetus are accompanied by AFP and HCG changes equal to Down syndrome pregnancies. The average marker's levels in cases of per inv (9) were: AFp-0.

[The prenatal diagnosis of Down's syndrome based on the biochemical screening of maternal serum markers].

The role of maternal alpha-fetoprotein and chorionic gonadotprin screening in complex prenatal diagnosis of Down syndrome had been studied. The average markers' values in cases of fetus trisomy 21 were 0.67 MoM (AFP) and 2.