[Quasichemical models of dynamics of cell populations after treatment with growth inhibitors and activators]. / Kvazikhimicheskie modeli dinamiki kletochnykh populiatsii pod deistviem ingibitorov i aktivatorov rosta.

A uniform procedure is proposed, whereby growth characteristics of biological populations of various levels can be described as quantum chemistry equations. Using approaches of the kinetics of chain processes expressions have been derived, which make it possible to assess the effects of individual chemical substances and mixtures thereof on population dynamics. These expressions describe quantitatively synergistic and antagonistic effects of the substances. The models proposed describe the kinetics of growth of various populations (such as cultures of microorganisms) and can serve as a basis for targeted regulation of biotechnological processes.

[IR-spectroscopic study of the interaction of chromium salts with native DNA]. / IK-spektroskopicheskoe izuchenie vzaimodeistviia solei khroma s prirodnoi DNK.

Infrared spectra of some unoriented films of DNA contained CrCl3, K2Cr2O7 and Cr2(SO4)3 have been obtained at relative humidities (r.h.) 0 to 93%. Chromium cations were shown to interact with phosphoric groups of DNA molecules. Cr2(SO4)3 or K2Cr2O7 content exceeds 0.1 Cr/P, the sugar-phosphate backbone of the double helix becomes irregular and nucleic bases unstacked, i.e. denaturation of DNA occurs. A very small amount of the salt, less than 0.01 Cr/P contained in DNA films prevents the conformational transition of the double helix from the B to A form induced by r.h. decreasing. The efficiency of the chromium salts in preventing the transition falls in the row: Cr2(SO4)3 > K2Cr2O7-CrCl3.

[Toxic effects of heavy metal salts on intact and irradiated cultured mammalian cells]. / Toksicheskoe deistvie solei tiazhelykh metallov na intaktnye i obluchennye kul'tiviruemye kletki mlekopitaiushchikh.

The toxicity of solutions of K2Cr2O7 and NiSO4.8H2O for cultivated Chinese hamster fibroblasts and murine lymphoma Sp-2 cells was determined using three criteria of damage: cell death (dyeing with trypan blue), inhibition of cell proliferation and their colony-forming activity. It was shown that both salts have equal toxicity in (10(-3)-10(-2)) M interval for both culture investigated relative to inhibition of cell proliferation. The threshold of toxicity of K2Cr2O7 relative to reproductive cell death (10(-4) M is smaller than to the inhibition of cell proliferation. The nontoxic concentration of K2Cr2O7 enhanced the radiation-induced reproductive death of fibroblast culture at doses 2 and 4 Gy.

[A variant of an operation of varicose veins of the esophagus and cardia in patients with portal hypertension syndrome]. / Variant operatsii na rasshirennykh ven pischevoda i kardii u bol'nykh s sindromom portal'noi gipertenzii.

On analysing universal experience, the authors suggest their variant of operation on varicose veins of the esophagus and cardia with the use of Doppler ultrasonography and intraoperative packing of the veins with a radiocontrast foamy polymer. With this method the flow of blood in the venous collaterals of the stomach and esophagus can be arrested more radically during the operation, which considerably reduces the percentage of recurrent bleeding from these veins.

[The differential diagnosis of splenic angiosarcoma and idiopathic myelofibrosis]. / O differentsial'noi diagnostike angiosarkomy selezenki i idiopaticheskogo mielofibroza.

The authors have made an analysis of literature and their own data on the differential diagnosis between angiosarcoma of the spleen and idiopathic myelofibrosis that is considered to be necessary due to the similarity of laboratory and clinical symptoms of these diseases.

[A method of suturing of dilated cardial veins in patients with portal hypertension]. / Metodika proshivaniia rasshirennykh ven kardii u bo'lnykh s porta'lnoigipertenziei.

Ultrasonic fluorometry used in 22 patients with portal hypertension facilitates the detection, marking the venous trunks of the cardia with inflammatory alterations of the mucosa. Intraoperative control of surgical treatment with the help of ultrasonic fluorometry allows operations to be performed more radically and to considerably reduce the intraoperative blood loss.

[Molecular mobility of soluble collagen]. / Molekuliarnaia podvizhnost' rastvorimogo kollagena.

Conformation structure of soluble collagen in anhydrous form, films and gels was studied by broad line NMR. An analysis of spectra points to partial ordering of polymer chains in the films and possible formation of secondary structure of collagen molecules by alpha-helix type. Distinction of gel spectra from those of films is explained by unordered rotation movements of the chain fragments at the expense of "superspiralization" of collagen molecules.