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61.
Composition on surface lipids of coniferous from Picea, Pinus and Larix genera (six plant species) are studied by spectral and chromatographic methods. Different content of carbonyl compounds in the summary fraction of surface lipids of coniferous, concerning componental content of hydrocarbon fraction and predominance of concrete fatty acids was shown. A substantial quantity of unethereficated fatty acids in surface lipids of plants is shown. 相似文献
62.
The influence of weak perturbations (up to 300 microT) in the natural magnetic field (MF) (induced by the introduction of three constant magnets) on the problem task solving in complex maze was studied in two groups of Wistar rats. Under the action of inhomogeneous magnetic field there were no spontaneous change of the orienting for the explorative activity independently of the individual in the presence of the organization of goal-directed behaviour. Instead of the expected explorative activity, the stable and deep locomotor depression developed after orienting in a new environment. Such a phenomenon was manifested only against the background of informational loading. Nevertheless, under these conditions a short external stimulations resulted in even faster rat learning than in the control animals. It is suggested that the MF characteristics play a crucial role in the transformation of the orienting (unconditioned activity) into the explorative (cognitive) activity. 相似文献
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EB Gurvich EV Gladkova OV Gutnikova AV Kostiukovskaia LE Kuzina VV Saprykova 《Canadian Metallurgical Quarterly》1993,(5-6):4-6
Hygienic, clinical and epidemiologic screening was performed in staff of asbestos and cement goods production enterprise. Various dystrophic processes of pharynx and nasal cavity appeared to prevail among upper respiratory tract diseases. Average exposure to dust during 22 years at the stated production can lead to asbestosis 0-I stage, average exposure during 20.5 years can result in dust bronchitis and occupational allergic dermatosis can result from average exposure to dust during 21 years. Retrospective cohort study of mortality within 1949-1988 failed to find oncologic risk in workers engaged into asbestos and cement goods production higher than in general population. 相似文献
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The acid-base properties and transformation of nystatin in water, methanol, 80 per cent ethanol, 70 per cent propanol and 70 per cent dimethylsulfoxide were studied. The data are indicative of a significant difference in the protolytic properties of the antibiotic in various solutions. Nonreversible conformative conversions of nystatin in water and methanol not connected with the loss of the antibiotic activity were observed. It is suggested that the molecule of nystatin in the above solutions could be in 3 main states, i. e. inert native and activated. The results of the study may be of use in development of the schemes for isolation of nystatin from the mycelium preparation of some of its water soluble forms. 相似文献