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871.
Neuronal responses of an isolated slab of auditory cortex (area AI) to intracortical stimulation at the level IV were studied in curarized cats by extracellular recording 3 weeks after isolation. Dispersion of response latencies in the isolated slab was reduced (compared with that observed soon after isolation); the predominant responses were mono- and disynaptic, and the number of discharges consisting of bursts of spikes increased. However, despite simplification of the structural and functional organization of the chronically isolated slab of auditory cortex, the conditions for complex polysynaptic interaction between neurons of all layers were preserved in it, and in each layer the character of such interaction depended on the distance of the neuron from the focus of origin of the excitation. [In the chronically isolated slab of auditory cortex, just as in the acutely isolated slab, late reponses of over 40 msec were absent.]I. I. Mechnikov Odessa State University. Translated from Neirofiziologiya, Vol. 14, No. 5, pp. 462–469, September–October, 1982.  相似文献   
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During the long term noradrenaline injection (0.56 microgram/kg/min-2 hours during six days) the number of connective tissue mast cells decreases in dogs. Mature cells disappears and the percentage of young forms increases. Marked degranulation develops. 5-10 cell groups and chains are formed. The increase of free heparin level and the activation of anticoagulant unit hemostasis correspond to these changes. It is due to mast cells discharge of biologically active heparin which is an unspecific adaptogen.  相似文献   
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878.
Changes in the spectrum of the opacity of biodispersions containing L. acidophilus at the stage of growth have been studied. The pronounced positive correlation between the opacity of dispersion and the titer of cells, determined by the method of ultimate dilutions, have been shown.  相似文献   
879.
The protective effects of alpha-tocopherol, carnosine and their mixtures on monoamine oxidase activity, accumulation of lipid peroxidation products, lipid fatty acid composition, hydrophobicity and microviscosity of synaptic membranes during lipid peroxidation were studied. It was shown that the protective efficiency is more higher when the mixture of water and liposoluble antioxidants was used.  相似文献   
880.
The action of T-activin on peritoneal macrophages of CBA mice after its introduction into the animals has been studied. In intact mice the phagocytic activity of macrophages and their resistance to the cytopathogenic action of Salmonella typhimurium live cells remains unchanged. The injection of corpuscular pertussis vaccine into mice leads to a decrease in the resistance of macrophages to the action of salmonellae. The simultaneous injection of T-activin into mice in doses of 0.1 and 1.0 microgram per animal abolishes the damaging action of the vaccine. The analysis of the in vitro action of T-activin on macrophages of intact mice revealed that the preliminary incubation of cells with the preparation sharply increases their resistance to the action of salmonellae, while its introduction simultaneously with bacteria or after them rapidly leads to the death of macrophages. The action of T-activin is supposed to be linked with triggering the biosynthetic processes mediating the resistance of macrophages to the cytopathogenic action of salmonellae.  相似文献   
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