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Biomedical subjects

G M Nikolaev

Publications and source records attributed to G M Nikolaev.

At least 19 recordsLinked to original sources
PubMed1987

[Determination of the kanamycin B content of kanamycin preparations by column chromatography].

Kanamycin B content in kanamycin preparations was determined with column chromatography and PMR spectroscopy. It was shown that coincidence of the results obtained with both the procedures in analysis of the preparations subjected to additional recrystallization was satisfactory. With the use of nonrecrystallized preparations the admixtures interfered with the results in using the developed procedure.

Anion Exchange Resins↗
PubMed1987

[Azlocillin stability in solutions and the solid state].

Stability of azlocillin in aqueous solutions at pH 1.5-12.5 was studied at various temperatures. It was shown that degradation of the antibiotic proceeded as an irreversible first order reaction. Dependence of 1gk on the reverse temperature was described by the Arrhenius equation. The highest levels of azlocillin stability in solutions were observed at pH about 6.0. In solid state azlocillin was stable under the effect of the environmental factors. In the atmosphere of oxygen and carbon dioxide and on exposure to light the quality parameters of the antibiotic powder maintained at the control levels.

Azlocillin↗
PubMed1980

Photo-induced electron transport and water state in Rhodospirillum rubrum chromatophores.

It is shown that in bacterial chromatophores the pronounced changes in the free water content with a proton spin-spin relaxation time (T2) of 10(-3)--10(-2) s does not influence the efficiency of electron transfer from the photosynthetic reaction centre to the membrane pool of secondary acceptors. An abrupt inhibition of this process occurs only after the loss of the water with faster proton spin-spin relaxation time (T2 of 10(-4) s). The process is reversible. The water fraction in question is obviously bound to the chromatophore proteins and forms the primary hydration layer.

Bacterial Chromatophores↗
PubMedDate not supplied

[Study of the embrotoxic properties of the repellent diethyltoluamide].

With application to the skin of an albino female-rat over the whole period of its pregnancy of the repellent diethyltolueneamide (DETA) in doses of 100 and 1000 mg/kg the overall embryonal fatality was found to go up, the size and weight of the rattlings to be down; there was recorded a lagging development of the newborns and a high postnatal death rate. The preparation could easily overcome the placental barrier, it was demonstrable in the placenta, fetuses, as well as in the bodies of newborn rattlings, even 3 months after their birth.

Administration, Topical↗
PubMedDate not supplied

[NMR spin-echo study of the effect of hydration on the mobility and conformation of linear polyethyleneimine].

It has been shown that mobility of protons in different groups of linear polyethylenimine (LPEI) is sensitive to the formation of H-bonds between amino groups of a polymer. Upon hydration of LPEI most of direct bonds between amino groups are substituted by the bonds via water molecules. This results in a conformational change of the polymer. Similar process may also occur in biopolymers.

Molecular Conformation↗