Search

The work is devoted to the assessment of gastric carcinoma spread using the method of spiral CT. It is established that CT is highly effective at carcinoma advanced stages (II-IV), that's why this method should be the main one in determining the disease spread. Besides the CT possibilities in determining the depth of tumor invasion into gastric wall are not unequivocal. The method is more informative at the advanced tumor (pT2-pT4). Without contrast amplification the CT doesn't allow to conduct differentiation according to T1-T2 invasion degree. At the same time the method gives great opportunities in revealing the tumor spread to gastric serous membrane, i.e. in detection of T3 invasion degree that is of great significance for disease prediction. The use of bolus contrast amplification widens the CT possibilities in detection of tumor invasion into gastric wall and in some cases it permits to differentiate T1 and T2 degrees.

Since Dec 1988, date of the French-Soviet joint space mission "ARAGATZ", the CIRCE device (Compteur Intégrateur de Rayonnement Complexe dans l'Espace) had recorded dose equivalent and quality factor inside the MIR station (380-410 km, 51.5 degrees). After the initial gas filling two years ago, the low pressure tissue equivalent proportional counter is still in good working conditions. Some results of three periods, viz Dec 1988, Mar-Apr 1989 and Jan-Feb 1990 are presented. The average dose equivalent rates measured are respectively 0.6, 0.8 and 0.6 mSv/day with a quality factor equal to 1.9. Some detailed measurements show the increasing of the dose equivalent rates through the SAA and near polar horns. The real time determination of the quality factors allows to point out high LET (Linear Energy Transfer) events with quality factors in the range 10-20.

Using data from dosimetry-radiometry system "Liulin" on board of "Mir"-space station the particle flux and doserate during September-October, 1989 has been studied. The orbit of the station was 379 km perigee, 410 km apogee and 51.6 degrees inclination. Special attention has been paid to the flux and doserate changes inside the station after intensive solar proton events (SPE) on 29 of September, 1989. The comparison between the doses before and after the solar flares shows increase of the calculated mean dose per day by factor of 10 to 200. During the SPE on the 29 of September the additional dose was 310 mrad. The results of the experiment are compared with the data for the solar proton fluxes obtained on the GOES-7 satellite.

Clinical, epizootological, and laboratory data for 9 endemic foci of hemorrhagic fever with renal syndrome (HFRS) were compared. The analysis covered 5120 cases of HFRS. It was established that in the foci, where the leading role is played by field mouse and Japanese field mouse, HFRS is caused by the 1st serotype of HFRS virus, and the clinical course of the disease is quite severe. In the natural foci with the predominance of redbacked vole, the 2nd serotype of the virus circulates and the disease is of moderate severity or mild. In each individual case, however, both serotypes of the virus may produce both mild and severe diseases.

This paper considers the possibility of characterizing space flight radiation safety, using a value which is integrated over the flight time, takes into account the radiation processes in an irradiated body and averages the probability of adverse radiobiological effects with respect to the distribution of solar proton flares of varying intensity. The proposed characteristic is compared with the current standards with reference to a hypothetic interplanetary flight.

The paper describes the radiation environment in the compartments of the orbital station Salyut-4 and in its flight orbit. It also discusses the measures taken to provide radiation safety of the crewmembers and the main results of radiation monitoring. During the flight the dose received by the crew was 1400 mrem.