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41.
Vasil'ev VV Orlov VI Chernositov AV Sagamonova KIu 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2004,54(4):466-472
Spectrum and coherent EEG analysis was performed in 86 pregnant women on the 35-36th week of gestation. It was shown that functional interhemispheric brain asymmetry is a sensitive index of normal and complicated gestation. It was found out that activation prevailing in the central and temporal brain areas contralateral to the side of placenta localization in the uterus was characteristic of the normal pregnancy. The development of gestation complications was accompanied by the inversion of interhemispheric asymmetry of EEG activation. It was suggested that correlative properties of bioelectric brain activity in women with normal gestation are an indicator of the left-hemispheric dominance of brain centers in the integration process. 相似文献
42.
Dmitrieva ES Gel'man VIa Zaĭtseva KA Orlov AM 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2004,54(5):581-591
Cerebral mechanisms of musical abilities were explored in musically gifted children. For this purpose, psychophysiological characteristics of perception of emotional speech information were experimentally studied in samples of gifted and ordinary children. Forty six schoolchildren and forty eight musicians of three age groups (7-10, 11-13 and 14-17 years old) participated in the study. In experimental session, a test sentence was presented to a subject through headphones with two emotional intonations (joy and anger) and without emotional expression. A subject had to recognize the type of emotion. His/her answers were recorded. The analysis of variance revealed age- and gender-related features of emotional recognition: boys musicians led the schoolchildren of the same age by 4-6 years in the development of mechanisms of emotional recognition, whereas girls musicians were 1-3 years ahead. Musical education in girls induced the shift of predominant activities for emotional perception in the left hemisphere; in boys, on the contrary, initial distinct dominance of the left hemisphere was not retained in the process of further education. 相似文献
43.
Apoptosis in serum-deprived vascular smooth muscle cells: Evidence for cell volume-independent mechanism 总被引:3,自引:0,他引:3
Orlov SN Pchejetski D Taurin S Thorin-Trescases N Maximov GV Pshezhetsky AV Rubin AB Hamet P 《Apoptosis : an international journal on programmed cell death》2004,9(1):55-66
Shrinkage is the earliest hallmark of cells undergoing apoptosis. This study examines the role of this phenomenon in the onset of vascular smooth muscle cell (VSMC) apoptosis triggered by growth factor withdrawal. In hyperosmotic media, VSMC showed the same amplitude of shrinkage but were more resistant to apoptosis than endothelial, epithelial and immune system cells. As with growth factor withdrawal, apoptosis in hyperosmotically-shrunken VSMC was sharply potentiated by transfection with E1A-adenoviral protein and was suppressed by activation of cAMP signaling as well as by the pan-caspase inhibitor z-VAD.fmk. Both cell shrinkage and apoptosis in VSMC-E1A treated with hyperosmotic medium were potentiated under sustained Na+, K+ pump inhibition with ouabain that was in contrast to inhibition of apoptosis documented in ouabain-treated, serum-deprived cells. After 1-hr incubation in serum-deprived medium, VSMC-E1A volume declined by approximately 15%. Transfer from hypotonic to control medium decreased VSMC-E1A volume by approximately 25% without any induction of apoptosis. Neither swelling in hyposmotic medium nor dissipation of the transmembrane gradient of K+ and major organic osmolytes protected serum-deprived VSMC-E1A from apoptosis. Thus, our results show that similarly to immune system, endothelial and epithelial cells, extensive VSMC shrinkage in hyperosmotic medium leads to the development of apoptosis. In contrast to hyperosmotic medium, the modest cell volume decrease occurring in serum-deprived VSMC does not contribute to triggering of the apoptotic machinery. 相似文献
44.
Na/K pump and intracellular monovalent cations: novel mechanism of excitation-transcription coupling involved in inhibition of apoptosis 总被引:3,自引:0,他引:3
The Na/K pump plays a key role in the regulation of the intracellular concentrations of monovalent cations and related cell function leading to electrogenesis and excitation-contraction coupling. We focus this review on the analysis of recent data showing that (i) inhibition of the Na/K pump triggers a signaling cascade independently of modulation of the intracellular [Na+]i/[K+]i ratio; (ii) elevation of [Na+]i under sustained inhibition of the Na/K pump leads to expression of a set of genes by [Ca2+]i-dependent and independent pathways; (iii) [Na+]i-sensitive genes are involved in the inhibition of programmed cell death (apoptosis) in vascular smooth muscle cells. 相似文献
45.
46.
A bacterial cell must distribute its molecular building blocks among various types of nutrient uptake systems. If the microbe
is to maximize its average growth rate, this allocation of building blocks must be adjusted to the environmental availabilities
of the various nutrients. The adjustments can be found from growth balancing considerations. We give a full proof of optimality
and uniqueness of the optimal allocation regime for a simple model of microbial growth and internal stores kinetics. This
proof suggests likely candidates for optimal control regimes in the case of a more realistic model. These candidate regimes
differ with respect to the information that the cells control system must have access to. We pay particular attention to one
of the three candidates, a feedback regime based on a cellular control system that monitors only internal reserve densities.
We show that allocation converges rapidly to balanced growth under this control regime.
Received: 20 November 2000 / Revised version: 7 August 2001 / Published online: 21 February 2002 相似文献
47.
Afanas'ev SV Tolkunov BF Rogatskaia NB Orlov AA Filatova EV 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2002,88(10):1260-1271
Simultaneous recording of unit activity of 6-8 putamen neurons in two monkeys (M. nemestrina and M. mulatta) during performance of the task of alternative spatial choice, was carried out. The extent of rearrangements of the activity in the groups of neurons with the transition from every step of the behavioral program to the next one and the degree of difference in mosaics of reactivity, forming at every step with a different variants of performance, were evaluated using discriminative analysis. The rearrangements of the impulse activity were recorded in all steps of the program. The dynamics of rearrangements with the choice of right or left feeder was different, which resulted in appearance of significant differences in mosaics of reactivity at the stage of decision making and receiving reward. The rearrangements preceding the task-oriented movement of one hand were more pronounced in the contralateral hemisphere. The volume of rearrangements may increase with the performance of movement but the differences of mosaics formed during the movement of right and left hand are decreasing. At the stage of reception of the reward, the rearrangements were greater in case the animal chose the certain (left) feeder irrespective of the side of recording the unit activity. 相似文献
48.
49.
Kurganov BI Kornilaev BA Chebotareva NA Malikov VP Orlov VN Lyubarev AE Livanova NB 《Biochemistry》2000,39(43):13144-13152
The thermal stability of rabbit skeletal muscle glycogen phosphorylase b was characterized using enzymological inactivation studies, differential scanning calorimetry, and analytical ultracentrifugation. The results suggest that denaturation proceeds by the dissociative mechanism, i.e., it includes the step of reversible dissociation of the active dimer into inactive monomers and the following step of irreversible denaturation of the monomer. It was shown that glucose 1-phosphate (substrate), glucose (competitive inhibitor), AMP (allosteric activator), FMN, and glucose 6-phosphate (allosteric inhibitors) had a protective effect. Calorimetric study demonstrates that the cofactor of glycogen phosphorylase-pyridoxal 5'-phosphate-stabilizes the enzyme molecule. Partial reactivation of glycogen phosphorylase b preheated at 53 degrees C occurs after cooling of the enzyme solution to 30 degrees C. The fact that the rate of reactivation decreases with dilution of the enzyme solution indicates association of inactive monomers into active dimers during renaturation. The allosteric inhibitor FMN enhances the rate of phosphorylase b reactivation. 相似文献
50.
Saukhat SR Vorontsov DV Tormozova NM Golubenko IA Kravchenko VF Poplavskaia TK Ternovaia NM Rabinovich VD Orlov NV Ryndich IV Prokopenkova SA 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2000,(4):89-92
The necessity and effectiveness of introducing the program of the exchange of syringes for intravenous drug users as a preventive and antiepidemic measure are discussed. Preventive and antiepidemic measures within the concept of harm reduction are described. The comparative analysis of materials obtained as a result of two sociological questionings, carried out in 1997-1998 among the representatives of the community (random nonrepeating choice) and in the middle of 1999 among the participants of the program revealed that the participants of the program had statistically significant changes in risky behavior patterns during the use of injection drugs. 相似文献