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991.
S M Borodkin O M Grindel' G N Boldyreva V A Za?tsev V I Luk'ianov 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1987,37(1):22-30
EEGs of 15 healthy subjects and 30 patients in early period after surgical ablation of tumours with basal localization, were investigated by means of monitor "Neuro-1" which allows to obtain in continuous regime characteristics of EEG dynamics according to power spectra and reveal the characteristics of intercentral relations of electrical brain processes by coherence and phase shifts. In healthy subjects in the period of transition from wakefulness to drowsiness highly coherent beta-rhythm (16-18 Hz) was revealed, preceeding typical picture of drowsiness and sleep. Study of the patients shows that certain characteristics of coherence and phasic shifts have an important prognostic value. Conclusion is made that for estimation of the functional state of healthy subjects during transition from wakefulness to drowsiness and of patients in early postoperative period the data on spectra of coherence are most informative. 相似文献
992.
993.
A V Bursian V O Voskresenski? O P Timofeeva 《Zhurnal evoliutsionno? biokhimii i fiziologii》1987,23(1):115-120
Studies have been made on the organization of the spontaneous motor activity during first 2 weeks of postnatal life of rats Rattus norvegicus (var albin.) by means of prolonged EMG recording from the gastrocnemius muscle and by computer analysis. Complexes of prolonged activity with a period of about 1 min, intracomplex periodicity of short pulses with a frequency 1/sec and periodicity of separate short bursts arranged into series with intervals between them of approximately 8-12 sec were observed. It was found that the main rhythm of these forms of excitation remains relatively unchanged during postnatal ontogenesis. The number of periods filled by series of short bursts decreases in postnatal development of animals, whereas the number of periods of a complete rest lasting for 1 1/2 and more minutes increases. These findings were compared with the development of sleep--wakefulness cycle in early postnatal ontogenesis. 相似文献
994.
Neurospecific and neuro-nonspecific isozymes of glycolytic enzyme enolase known to be molecular markers of neuronal and glial cells respectively were isolated from human brain. Using immunoenzyme assay, the content of these proteins was measured in the brain of 7-13-week human embryos and adult subjects. The content of both isoenzymes gradually increases attaining constant level in 10-13-week embryos. Relative content of neuro-nonspecific enolase in the brain of 10-13-week embryos is 1 1/2 times higher than that in adults, whereas the content of neurospecific enolase amounts only to 2% of its level in the adult brain. 相似文献
995.
996.
997.
V S Lushchekin E A Lushchekina K V Shule?kina N G Gladkovich 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1987,37(4):688-695
Study of development of early forms of behaviour was carried out on intact kittens of the first month of life, who endured in 5 days age uni- and bilateral sections of the lingual nerve, and on shame-operated and undernourished animals. It was shown that bilateral deafferentation caused significant disturbance of alimentary behaviour at the stage of sucking, manifested in disturbance of natural sucking and appearance of shame sucking, i.e. rhythmic sucking movement without nipple grasping. At the one-month age, in conditions of artificial feeding, natural sucking in operated animals was restored and the shame one disappeared. Bilateral section of the lingual nerve led to acceleration of ripening of sensory and motor systems and accelerated development of homing, exploratory and playing behaviour. Possible role is discussed of sensory trigeminal nuclei neurones in organization of normal patterned sucking and at limited sensory inflow. It is suggested that elimination of sensory input developing in the norm earlier than others, changes natural terms of other channels development, what accelerates the change of early behaviour forms. 相似文献
998.
Carbocyclic analogues of dTTP and UTP: properties in polymerase enzyme-catalyzed reactions 总被引:1,自引:0,他引:1
Racemic carbocyclic analogues of dTTP [(+/-)-C-dTTP] and its ribo counterpart, 5-methyl-UTP [(+/-)-C-m5UTP] were synthesized and examined, in comparison with dTTP and UTP (and m5UTP), as potential substrates of E. coli DNA and RNA polymerases, respectively. Unexpectedly, only a very low (terminal) incorporation of C-dTMP into DNAs of different structure was observed, C-dTTP did not serve as a substrate for chain elongation by the Klenow DNA polymerase. Inhibition of DNA replication was, however, observed in the presence of (+/-)-C-dTTP. The UTP analogue, (+/-)-C-m5UTP proved neither a substrate nor an inhibitor of the RNA polymerase enzyme. 相似文献
999.
A single neonatal treatment of rats with vitamin D3, gibberellin, allylestrenol or diethylstilbestrol (DES) influenced the ouabain binding capacity of myocardial Na, K-dependent ATP-ase. Of the active molecules tested, vitamin D3, DES and gibberellin had appreciable impact on myocardial ouabain receptors, enhancing and depressing their activity, respectively. The thymic dexamethasone and uterine estrogen receptors did not alter their binding capacity in response to neonatal exposure to vitamin D3 or gibberellin. 相似文献
1000.
Earlier the autophosphorylation of myosin and the labile phosphate (P) content of rabbit skeletal muscle was reported [6, 7, 9]. The present paper describes that the endogeneous preformed P level in fresh preparation of exercised muscle is higher than that of untrained control one. It was revealed that the presence of a significant amount of mitochondrial myosin (with much higher P content) in the well-trained human muscle preparations falsified the appreciation of myofibrillar myosin. Therefore, a reliable myofibrillar preparation with correct P content from exercised subjects was obtained only after the separation of mitochondrial fraction. The P content of fresh preparations can be increased by phosphorylation even in the exercised muscle myosins up to the most higher level in human samples. The phosphoryl group incorporation from [gamma-32P]ATP into the rabbit and hare myosins was checked by radioactive tracer technique, and confirmed by total P content determination performed parallel with molybdate test. It was stated that under present circumstances the labelled 32P incorporation was lower even at an optimal substrate concentration than that of P value obtained directly with molybdate method; because the total P content of preparations had not exchanged during 2 min incubation. So it has been concluded from [gamma-23P] phosphoryl group assayments that much higher amount of P was incorporated into P-Arg, N pi-P-His and fraction 2 as compared with unappreciated labelled P level of the inorganic P (P-Ser, P-Thr), P-Lys, N tau-P-His and minor fractions. From these observations it has been considered that the P-Arg, N pi-P-His and fraction 2 take part in the contraction mechanism and in the course of physical training. 相似文献