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981.
Osadchiĭ OE Pokrovskiĭ VM 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》1997,83(3):49-58
In anaesthetised cats, an increase in the vagal burst rate resulted in a paradoxical decrease of vagal bradycardia. This seems to be due to a shift of the vagal stimulus position towards early phase of cardiac cycle. The mechanism of this paradoxical effect depends on the magnitude of vagal chronotropic effect upon the time of vagal stimulus delivery within cardiac cycle. 相似文献
982.
Talalaenko AN Babiĭ IuV Perch NN Vozdvigin SA Panfilov VIu 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》1997,83(3):88-94
Chlordiazepoxid, phenibut, indoter, campiron, campironin, when administered into the amygdala, improve the anxiety condition of rats in avoidance tests and resemble by their effects dophamine, GABA, or serotonin. Observed differences in the anxiolytic effects between anxiosedative and anxioselective agents seem to be due to an unequal contribution of the monoamin- and aminoacidotergic transmitters into the mechanisms of heteromodal aversive anxiety genesis in the basolateral area of the amygdalar complex. 相似文献
983.
Shandra AA Godlevskiĭ LS Brusentsov AI Vast'ianov RS Karliuga VA Dzygal AF Nickel B 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》1997,83(3):95-99
An anti-ischemic effect of the delta-sleep-inducing peptide (DSIP) was found in rats. The DSIP effect was more obvious than that of the MK-801. The data obtained is discussed considering a possible use of the DSIP for brain stroke prophylaxis. 相似文献
984.
Gas exchange and oxygen transport during long term hypothermia following a hypothermal apnea in rats
Chuĭkin AE Fedorova TE 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》1997,83(4):103-110
The data obtained show that, at the initial stages of hypothermia, a decrease in the oxygen consumption and carbon dioxide production, cardiac output, and heart rate occurred in accordance with the temperature coefficient. Suppression of the tissue gas exchange was unrelated to disorders in the lung gas exchange but determined rather by a progressing weakening of heart activity, decrease in the cardiac output, and increase in the general vascular peripheral resistance. 相似文献
985.
V V Kravchenko V V Shamin I P Gileva V A Likhoshva? V N Dobrynin 《Bioorganicheskaia khimiia》1988,14(10):1372-1386
The role of the translational terminator and initiator signals arrangement for two adjacent genes in polycistronic mRNA has been studied. Semisynthetic beta-galactosidase gene (lacZ) of E. coli and fragment of phage M13 DNA (with promoter PVIII, gene IX, and part of gene VIII) were used for constructing of the IX-VIII-lacZ artificial polycistronic operon. Cloning of the constructs into pBR322 vector resulted in a number of pLZ381N plasmids differing by the mutual arrangement of gene VIII translation terminator codon and SD site and initiator codon (SD-ATG-region) of lacZ gene. The mutual arrangement of gene VIII terminator codon and SDlacZ-ATG region has been altered by means of deletions and insertions that have not affected lacZ translation initiation signals. The beta-galactosidase (beta-Gal) synthesis in E. coli harbouring different types of pLZ381N plasmids has been found to depend on type of cistron coupling (gene VIII and lacZ). The overlapping of terminator and initiator codons (ATGA) for genes VIII and lacZ (type I of polycistrons) provide approximately equal translational level for both cistrons. On the other side, levels of beta-Gal synthesis in case of polycistrons type II (gene VIII stop-codon position at the beginning of SDlacZ or 10 nucleotides upstream) were 20-30 times as high as for type I. Differences in beta-Gal levels have also been found for variants of VIII-lacZ coupling in types IV and III polycistrons (the SDlacZ-ATG region in 27-50 nucleotides downstream from the proximal cistron VIII stop-codon, which, in turn, is 41 nucleotides upstream this terminator). These data cannot be explained on the basis of possible secondary structure including the SDlacZ-ATG region and other parts of polycistronic mRNA. In all these cases similarly stable stem-loop structures have been found. Therefore, the arrangement of the translation termination and initiation signals for two adjacent genes in essential for distal gene translation efficiency. One can imagine that ribosome or its 30S subpartical, stalling on the proximal gene terminator codon, affects the distal gene translation initiation. 相似文献
986.
987.
988.
The influence of ionizing radiation with low absorbed dose rate (55 mGy x min(-1)) in 1, 12 and 24 hours after irradiation in doses of 0.1; 0.5 and 1.0 Gy on functional state of the electron transfer chain of the rat small intestine mitochondria was investigated by assessment of the oxygen consumption rate. The uncoupling of oxidation and phosphorylation, a decrease of phosphorylation rate and inhibition of ATP hydrolysis reactions were established in mitochondria in dependence on the irradiation dose and time interval after irradiation. The functional peculiarities of the oxidation-phosphorylation coupling sites of the mitochondrial electron transfer chain were detected. 相似文献
989.
Ponomar'ova AG Iurenko IeP Zhurakovs'kyĭ RO Govorun DM 《Ukrainski? biokhimicheski? zhurnal》2012,84(1):67-78
Comprehensive conformational analysis of the biologically active nucleoside 2',3'-didehydro-2',3'-dideoxyaguanosine (d4G) has been performed at the MP2/6-311++G(d,p)//DFT B3LYP/6-31G(d,p) level of theory. The energetic, geometrical and polar characteristics of twenty d4G conformers as well as their conformational equilibrium were investigated. The electron density topological analysis allowed us to establish that the d4G molecule is stabilized by nine types of intramolecular interactions: O5'H...N3, O5'H...C8, C8H...O5', C2'H...N3, C5'H1...N3, C5'H2...N3, C8H...H1C5', C8H...H2'C5' and N2H1...O5'. The obtained results of conformational analysis permit us to think that d4G may be a terminator of the DNA chain synthesis in the 5'-3' direction. Thus it can be inferred that d4G competes with canonical 2'-deoxyaguanosine in binding an active site of the corresponding enzyme. 相似文献
990.
Pirutin SK Turovetskiĭ VB Kedrov AV Kudriashov IuB Shaĭtan KV Rubin AB 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2012,52(3):252-256
Our study has shown that the damaging effect of hydroxylated fullerene C60(OH)25 on mouse peritoneal macrophage plasma membranes increased when we enlarged the concentration of fullerene in the incubation media (from 0.005 to 0.5 mg/ml), the incubation temperature (from 22 degrees C to 37 degrees C) and the time of incubation (from 30 to 90 min). In conditions of the H2O2-induced membrane damage, fullerene was observed to intensify the H2O2-induced damaging effect at a concentration of 0.05 mg/ml and reduce it at a concentration of 0.5 mg/ml. In conditions of the UV-induced membrane damage, it was discovered that the damaging effect of UV increased when C60(OH)25 nanoparticles were added to the incubation media before irradiation and decreased when they were added after irradiation. Eventual participation of ROS in damaging effects of C60(OH)25 was discussed. 相似文献