Potentiometric membrane sensors for polyvinylpyrrolidone determination.

Potentiometric sensors were developed for determining the concentration of the physiologically active polymer polyvinylpyrrolidone (PVP) with the use of its adduct with triphenylmethane and azodyes as electrode-active substances in plasticized membranes. The influences of electrolyte and pH of standard solutions on the electrode characteristics were determined. Polyvinylpyrrolidone determination in aqueous solutions of drug compounds, biological fluids and sewage was offered.

[Role of radionuclide imaging of bone marrow and spleen in choice of therapy and topometric preparation for radiotherapy of patients with Hodgkin disease].

Use of radionuclide methods of bone marrow (BM) and spleen visualization was assessed in 176 patients with primary Hodgkin's disease and 116 relapsing cases. The study was intended to help design treatment modality and carry out topometric measurements for exposure to radiation. Stage of tumor was revised in 19 primary patients as a result of BM scintigraphy, and this factor was responsible for major changes in the treatment modality in 11 patients (6.

[Cleavage of the side chain of sitosterol by R, S and M mycobacteria variants].

The purpose of this work was to study the capability of the R, S and M variants of 12 strains belonging to 5 mycobacterial species to decompose sitosterol and to transform it, in the presence of 8-hydroxyquinoline, yielding pregnenecarboxylic acid, androst-1,4-diene-3,17-dione, androst-4-ene-3,17-dione and sitostenone. All of the cultures decompose sitosterol, the cells of the M variant being most active and the cells of the R variant having the lowest activity. Differences in the products of transformation were observed not only among species, but also, to a strong degree, among variants of one and the same mycobacterial species.