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High reactivity and, at the same time, flexibility of interneuronal contacts were observed after exposure of rat head to 2-100 Gy radiation. At high doses (200-400 Gy) radiation-induced changes played a major role in the development of the cerebral form of radiation sickness. A complete asynapsis is probably one of the causes of the animals death "under the ray" (irradiation of the head with a dose of 1000 Gy). 相似文献
3.
The radioprotective effect of gas hypoxic mixtures containing 5, 7, 8, 10 and 15% of oxygen on mice and rats was comparatively studied. The dependence of DMF upon oxygen concentration in the mixture was approximated by a hyperbolic function similar to the dependence of the radiomodifying effect of circulatory hypoxia caused by radioprotective agents of the indolylalkylamine series. 相似文献
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5.
Knud IB Christensen 《Nordic Journal of Botany》1983,2(6):537-548
Crataegus curvisepala Lindm., C. laevigata (Poiret) DC. and C. monogyna Jacq. (Rosaceae) form hybrid complexes in Denmark due to introgression. C. palmstruchii Lindm. seems to be variously introgressed individuals of C. laevigata. C. eremitagensis Raunk., C. raavadensis Raunk. and C. schumacheri Raunk. apparently belong to C. curvisepala x laevigata. The delimitation between C. curvisepala x laevigata and C. laevigata x monogyna is discussed. 相似文献
6.
Cytochemical activity of succinate dehydrogenase (SDG), L-glycerophosphate dehydrogenase (L-GPDG), lactate dehydrogenase (LDG), and glutamate dehydrogenase (GDG) increased immediately after total-body irradiation with a dose of 129 mC/kg. After 2 h, LDG activity only returned to the control level. Irradiation of the head with the same dose caused less pronounced changes. Changes caused by lethal irradiation (1290 mC/kg) were different: there was an increase after exposure of the abdomen and a decrease in the activity of SDG and L-GPDG after irradiation of the head. 相似文献
7.
An analysis is made of the current break process in microsecond plasma opening switches and their possible application in high-current generators. Necessary conditions are determined for generating megavolt pulses in the erosion mode of a plasma opening switch with the gap insulated by an external magnetic field. Under these conditions, efficient sharpening of high-power submegampere current pulses can be achieved. The possibility of using plasma opening switches operating at voltages of 5–6 MV to generate X-ray and gamma emission is discussed. The main operating and design parameters of a six-module plasma opening switch with a current pulse amplitude of 3.7 MA and voltage of 4–6 MV for use in the MOL generator, which is the prototype of one of the 24 modules of the projected Baikal multimegajoule generator, are estimated by using the available scalings. 相似文献
8.
The authors showed a pronounced and stable decrease in sexual motivation of male rats immediately after gamma-irradiation of the head with a dose of 2.58 C/kg. Exposure of the body to 1.29-2.58 C/kg radiation also inhibited sexual behaviour but only by the 45th-55th minute following irradiation: with higher doses some increase in sexual activity was observed immediately after irradiation. 相似文献
9.
The results of comparing the solutions of the direct task of electroencephalography on a spherical model and a spherical model
with one nonuniformity are discussed. The nonuniformity was simulated by two parabolas situated on the same axis of symmetry
and crossing the boundary of the gray and the white matter. The region between the larger and the smaller parabolas had the
physical characteristics of the gray matter, and the region inside the smaller parabola had the characteristics of the cerebrospinal
fluid. The task was to find a combination of parameters (distance between the dipole and the nonuniformity, angle of rotation
of the dipole relative to the nonuniformity, sizes of the dipole and the nonuniformity, etc.) that provides the maximum effect
of the difference of potentials on the outer surface of the scalp in the spherical model with one nonuniformity and the spherical
model. The influence of the points of grounding on the value of the effect was analyzed (ground only at the right ear and
ground at both ears). The data obtained show that a maximum difference of potentials is reached at the positions of dipoles
close to tangential relative to the scalp surface. 相似文献
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