[Change of cholinesterase relative activity under modulated ultra high frequency electromagnetic radiation in experiments in vitro].

Changes in the activity of enzyme cholinesterase (ChE) have been experimentally investigated under the influence of amplitude-modulated super-high-frequency electromagnetic radiation (carrier frequency of 2.375 MHz; power flux density of 8 mW/cm2, 20 mW/cm2 and 50 mW/cm2; modulation frequency range 10 to 210 Hz; exposure time 5 min). The appearance of peaks of the cholinesterase increased relative activity, as well as the changes in the direction and intensity of the reaction associated with the modulation frequency and power flux are observed at equal power flux densities and exposure times.

[Congelation of cryoprotective solutions and cryopreservation of fish sperm].

The influence of additional components and the velocity of cooling on the freezing of cryoprotective solutions has been studied using the cryomicroscopy technique. It was shown that additional components and the rate of cooling of cryoprotective medium fundamentally change the ice area of microparticles and the survival of fish spermatozoa during the freezing-thawing procedure.

Use of ultrasonic standing wave in biological studies and cell technologies.

In experiments on rat erythrocytes and yeast cells, we studied processes of concentration, separation, and isolation of native cells in suspensions by using standing ultrasonic wave field. Fifteen parameters essential for these processes were determined, and the applications of ultrasonic stratification, concentration, and cell separation methods under experimental conditions were determined.

[Thermoelastic excitation of acoustic waves in biological models under the effect of the high peak-power pulsed electromagnetic radiation of extremely high frequency].

The capability of high peak-power pulsed electromagnetic radiation of extremely high frequency (35,27 GHz, pulse widths of 100 and 600 ns, peak power of 20 kW) to excite acoustic waves in model water-containing objects and muscular tissue of animals has been experimentally shown for the first time. The amplitude and duration of excited acoustic pulses are within the limits of accuracy of theoretical assessments and have a complex nonlinear dependence on the energy input of electromagnetic radiation supplied. The velocity of propagation of acoustic pulses in water-containing models and isolated muscular tissue of animals was close to the reference data.

[Survival of amphibian embryos after continuous ultrasound treatment].

The influence of continuous ultrasound on the embryonic development of grass frog Rana temporaria has been investigated. Intact embryos at the blastula stage were treated by ultrasound of different frequency (0.88 and 2.

[Changes in the permeability of amphibian embryo envelope for fluorochromes under the action of ultrasound].

It was determined whether high-frequency ultra sound can change the permeability of gray toad Bufo bufo and grass frog Rana temporaria under the action of high-frequency ultrasound. The changes in the permeability of embryonic envelope were assessed by using slowly penetrating fluorochromes ANS, FDA, and fluorescein. It was found that the ultrasound of 0.

The effect of gas bubbles on the production of ultrasound hyperthermia at 0.75 MHz: a phantom study.

Transparent phantoms, made of bovine hide gelatine, have been constructed in order to study the consequences of the occurrence of cavitation in tissues. Gas pockets of about resonant size, physically introduced into the gel, lead to a mean temperature rise of 41 +/- 15 degrees C in 1 min, when the gel of concentration 11.4% (w/v) is sonicated in the continuous-wave (cw) mode at 1 W cm-2 (spatial average) and 0.

Interaction of therapeutic ultrasound with purified enzymes in vitro.

The effects of ultrasound on the rates of the catalytic reactions of four purified enzymes in vitro have been extensively investigated under a wide range of biochemical and physical exposure conditions. In general, it can be concluded that therapeutic intensities of continuous wave 0.88 MHz ultrasound had no detectable direct effects on the rates of the reactions catalysed by creatine kinase, lactate dehydrogenase, hexokinase and pyruvate kinase.