排序方式: 共有43条查询结果,搜索用时 15 毫秒
21.
G. V. Zhukova A. I. Shikhliarova A. V. Soldatov T. A. Barteneva I. A. Goroshinskaya V. I. Petrosian T. N. Gudtskova M. I. Bragina O. E. Polozhentsev E. A. Sheiko N. M. Maschenko E. A. Shirnina E. Yu. Zlatnik P. S. Kachesova T. A. Kurkina 《Biophysics》2016,61(2):303-315
The methods for activating antitumor resistance mechanisms that were developed using the concept of the periodic system of general nonspecific adaptational reactions of the body are briefly reviewed. The principles that allow effective impacts with electromagnetic radiation and biologically active substances are described. The criteria and concepts of the theory of adaptational reactions are compared to some of the concepts and categories of synergetics. The specific features in the dynamics of the studied parameters that are induced by effective impacts are considered. The antistress nature of the systemic effect that is caused by ferromagnetic nanoparticles on animals with grafted tumors is shown. Possible mechanisms that underlie the regression of large tumors that is caused by two different factors, viz., modulated electromagnetic radiation and magnetite nanoparticles, are discussed. The cases where the order parameter changed with the development of antistress unresponsiveness and regression of experimental tumors caused by a combined electromagnetic exposure are analyzed. 相似文献
22.
The effect of left ventricular (LV) contrast ventriculography (VG) on the state of intracardiac hemodynamics during the administration of a contrast medium and 30-40 sec. after it was investigated in 48 CHD patients. It followed retrograde catheterization of the left ventricle by a parallel use of two catheters that permitted recording intraventricular pressure directly during LV VG. The performance of left VG with 76% urografin administered in a dose of 0.6-0.8 ml/kg with the rate of 13-15 ml/s produced no significant change in the state of intracardiac hemodynamics, relaxation and pumping function of the LV in the course of the first three contrasted cardiocycles. Transitory disorder of hemodynamics observed in the patients after contrast VG was restored by itself in 15-20 min. 相似文献
23.
L L Oganesian A S Boiadzhian S A Petrosian K G Karagezian 《Molekuliarnaia biologiia》1991,25(1):99-104
The interaction of acidic copper-containing protein from the membranes of chromaffin granules has been investigated with cytochrome b-561 and dopamine-beta-monooxygenase from the same source. By the use of spectral and polarographic measurements it was demonstrated that the acidic copper-containing protein acts as an electron acceptor for cytochrome b-561 and as electron donor in the reactions, catalyzed by dopamine-beta-monooxygenase. According to the data obtained the possible function of the acidic copper-containing protein in vivo on the area of electron transfer chain between cytochrome b-561 and dopamine-beta-monooxygenase are discussed. The activation or inhibition of the electron transfer reactions by a variety of phospholipids, analogs of membrane lipids of chromaffin granules has been established. The experiments were performed in a model systems by the use of highly purified preparations of proteins and bilamellar liposomes and micelles, prepared from the corresponding phospholipids. 相似文献
24.
E S Gabrielian S E Akopov A A Kharatian A K Petrosian 《Biulleten' eksperimental'no? biologii i meditsiny》1986,101(1):79-81
Disorders in prostacyclin control of the functional state of thrombocyte-vascular wall system are associated rather with decreased PGI2 stability in the blood flow, its accelerated decomposition and as a result with its shorter and weaker effect on thrombocyte-vascular hemostasis, than with the decline in PGI2 synthesis. It is suggested that rapid PGI2 decomposition in irradiation may significantly limit its therapeutic effect, requiring adequate correction of PGI2 dosage and mode of administration. 相似文献
25.
Malysheva DN Darevskiĭ IS Tokarskaia ON Petrosian VG Martirosian IA Ryskov AP 《Genetika》2006,42(5):581-586
Using multilocus DNA fingerprinting with microsatellite probes (CAC)5, (GACA)4, (GGCA)4 and (GATA)4, intraspecific variation of the Southeast Asian lizards belonging to the genus Leiolepis (bisexual species Leiolepis reevesii and triploid parthenogenetic species Leiolepis guentherpetersi) was first examined. The L. guentherpetersi lizards were characterized by monophyletic DNA fingerprint profiles for the loci detected by the (GACA)4, (GGCA)4, and (CAC)5 probes, in terms of intrapopulation similarity index constituting S = 0.96. This was different from the individual-specific profiles of the lizards from bisexual, presumably parental species, L. reevesii (S = 0.6; P < 0.001). Genetic homogeneity of triploid L. guentherpetersi lizards at the loci examined serves as one of the arguments for the parthenogenetic nature of this species. Genetic variability of triploid parthenogenetic species L. guentherpetersi appeared to be comparable with that reported earlier for the Caucasian rock lizards of the genus Darevskia, namely, D. dahlia, D. armeniaca, and D. unisexualis (P > 0.05). The results of DNA fingerprinting analysis of the same L. guentherpetersi samples with the (GATA)4 hybridization probe were unexpected. Variability of parthenogenetic species L. guentherpetersi at the (GATA)n markers was remarkably higher than that at other DNA markers (S = 0.35; P = 3.08 x 10(-11)), being comparable to the variation of the (GATA)n DNA markers in bisexual species L. reevesii (P = 0.74). The reasons for high polymorphism of the (GATA)n-containing loci in L. guentherpetersi still remain unclear. This polymorhism is probably associated with high instability of the loci, which can be revealed by means of family analysis of parthenogenetic offspring. 相似文献
26.
Contribution of proton linkage to the thermodynamic stability of the major cold-shock protein of Escherichia coli CspA
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Petrosian SA Makhatadze GI 《Protein science : a publication of the Protein Society》2000,9(2):387-394
The stability of protein is defined not only by the hydrogen bonding, hydrophobic effect, van der Waals interactions, and salt bridges. Additional, much more subtle contributions to protein stability can arise from surface residues that change their properties upon unfolding. The recombinant major cold shock protein of Escherichia coli CspA an all-beta protein unfolds reversible in a two-state manner, and behaves in all other respects as typical globular protein. However, the enthalpy of CspA unfolding strongly depends on the pH and buffer composition. Detailed analysis of the unfolding enthalpies as a function of pH and buffers with different heats of ionization shows that CspA unfolding in the pH range 5.5-9.0 is linked to protonation of an amino group. This amino group appears to be the N-terminal alpha-amino group of the CspA molecule. It undergoes a 1.6 U shift in pKa values between native and unfolded states. Although this shift in pKa is expected to contribute approximately 5 kJ/mol to CspA stabilization energy the experimentally observed stabilization is only approximately 1 kJ/mol. This discrepancy is related to a strong enthalpy-entropy compensation due, most likely, to the differences in hydration of the protonated and deprotonated forms of the alpha-amino group. 相似文献
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28.
Oganesian NM Petrosian ShM Miridzhanian MI Asrian KV Pogosian AS Oganesian AN Abramian AK Arutiunian GR Karapetian AG Gevorkian EG Petrosian ZhG Arutiunian NK 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2006,46(3):341-347
The aim of this work is the analysis of the indices of the health and of the structure of the sicknesses of the inhabitants of Armenia who took part in the liquidation of the consequences of the Chernobyl accident. Also it is the determination of possible dependence of the frequency of diseases for the most widespread classes of sicknesses on the received dose of the irradiation, according to the data of the clinical examination and dispensarysation; and also it is the revelation of the role of other factors influenced on the health indexes. 相似文献
29.
Stoliarov DP Protopopov AV Burenkov GI Kochkina TA Konstantinov EP Vakhrushev SG Krasitskiĭ II Petrosian VV Usanin AN Putilin AV 《Vestnik rentgenologii i radiologii》2003,(1):26-31
In 1992-2001 seventeen patients with juvenile nasopharyngeal angiofibromas (JNAs) were treated at Krasnoyarsk Territorial Clinical Hospital. The patients underwent a comprehensive diagnosis involving computed tomography (CT), magnetic resonance imaging (MRI), and angiography, followed by tumor vascular embolization. Later on JNAs were surgically removed in 14 patients, a course of radiation therapy was performed. In suspected JNA, the authors consider it necessary to concomitantly use CT, MRI, and angiography, which provides the most complete diagnostic picture of a pathological focus. X-ray endovascular occlusion considerably lowers blood loss, facilitates a complete angiofibroma removal, and affects the tolerability of radiation therapy in inoperable cases. 相似文献
30.
A technique for obtaining unbiased estimates of genetic parameters (allelic frequencies of RAPD loci, heterozygosity (H), Wright's F statistic, and Nei's genetic distances) in populations of the European (Capreolus capreolus L.) and Siberian (Capreolus pygargus Pall.) roe deer is presented. The technique employs jackknifing and multiple comparative analysis based on a modified Holmes's procedure for Bonferroni's test. It was demonstrated that samples from local groups of roe deer in the Trans-Ural region did not differ significantly in allelic frequencies (0.8, 0.81, and 0.78; P > 0.447) or Nei's genetic distances (0.0056, 0.0273, and 0.0218; P = 0.26), but they could be differentiated based on Wright's F statistic (0.0346, 0.0519, and 0.0450; P = 10(-9)). The parameters of intrapopulation heterozygosity (from 0.18 to 0.042) formed a gradient from the east to the west. Calibration estimates of molecular evolution rate in the family Cervidae obtained based on published data and Jukes-Cantor genetic distances estimated in this study demonstrated that the Siberian roe deer has split into two subspecies, C. pygargus pygargus Pall. and C. pygargus tianschanicus Satunin in the interval between 229 and 462.3 thousand years ago. The species formation of the Siberian and European roe deer was dated between 1.375 and 2.75 Myr ago. Based on the results obtained we recommend the approaches used in the study for analysis of population genetic structure and phylogenetic relationships between populations, subspecies, species, and higher taxa. 相似文献