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Biomedical subjects

L Novak

Publications and source records attributed to L Novak.

At least 37 records · Page 2Linked to original sources
PubMed1979

Organic solvent soluble lipofuscin pigment in brain tissues of mice fed large amounts of polyunsaturated fats in presence and absence of various antioxidants.

The amount of lipid soluble fluorescent pigment is compared in brain tissues of mice fed a diet containing 10% safflower oil with and without a supplement of antioxidants as Vitamin E, Ascorbyl-Palmitate and Sodium-Selenite. Addition of 0.2 g/kg Vitamin E to the diet gives a high raise in the mortality. The addition of 0.2 g/kg Vitamin E and 0.5 g/kg Ascorbyl-Palmitate leads to higher values of extractable lipid soluble fluorescent pigment in mice brain tissues.

Animals↗
PubMed1976

Heat exchange between the organism and environment under conditions of weightlessness; methodical approach.

The spontaneous streaming of air around surfaces of warm bodies conditioned by gravitation is missing in the weightless condition. This implies a change in the thickness of the surface air layer and its interference with the heat output of an organism. The paper describes the use of an electric dynamic katathermometer (EDK) for automatic and continuous scanning of heat output and presents results of measuring basic characteristics of the surface layer under defined laboratory conditions, and their relation to heat output.

Air Movements↗
PubMed1974

Respiratory gas exchange as an indicator of changed radioresistance in mammals.

The paper deals with the problem of detection of radio-protective effects during irradiation. The method used is based on the fact that the known effective pharmacological and chemical radioprotectives (aminoethylthiouronium bromide HBr (AET), cystamine, sodium fluoroacetate (FAc), 5-hydroxytryptamine (5-HT), 5-methoxytryptamine (5-MT) and others) interfere directly or indirectly with enzymatic steps in energy metabolism of the organism. In mammals they induce at the same time an increase of resistance against ionizing radiation and a decrease in the respiratory gas exchange expressed by a depressed oxygen consumption. In experiments carried out on male mice of the H strain and male rats of the Wistar strain it was found that animals respiring a hypoxic mixture (5-8% O2, STPD), have a lower oxygen consumption during the period of increased radioresistance similar to that seen during the effect of radioprotective drugs. This finding is of practical importance as it enables one to evaluate quantitatively the effect of radioprotective measures (including the hypoxia) in individual experimental animals during the course of irradiation.

Animals↗
PubMedDate not supplied

[Prognostication of man's health status in response to gravity-induced blood shifts based on continuous noninvasive measurement of arterial blood pressure using the Pen'iaz method].

Exposure to +Gz acceleration, orthostatic tilt tests and LBNP tests causes distinct blood shifts and deterioration of cerebral circulation. In this case syncope episodes may be prevented by continuous monitoring of circulation parameters, specifically arterial pressure (AP). Our investigations have shown that continuous AP measurement by the Penjaz noninvasive technique may help earlier prediction of the health status in response to gravity-induced blood shifts. In this situation the development of a pre-collapse state is preceded by an emergence of distinct AP waves of the second-third order accompanied by a critical drop of pulse pressure. It is concluded that continuous AP measurement in the finger according to the Penjaz noninvasive technique holds promise as a medical monitoring method in a altered gravitational field.

Acceleration↗