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91.
92.
We studied peculiarities of the spectral characteristics of EEG in 111 healthy adult subjects of both sexes. The levels of
situative anxiety (anxiety state) and personal anxiety were estimated using the Spielberger–Khanin test system. To estimate
anxiety-related properties of the personality, Cattel’s technique 16 PF (form А) was used. Estimates of situative anxiety
demonstrated only two cases of positive correlation with the spectral power density (SPD) of EEG rhythms (SPDs of the beta2
rhythm in the right-hemisphere temporal and occipital regions; recording with the eyes open). Estimates of personal anxiety
positively correlated with the SPDs of the beta1 and (especially) beta2 EEG rhythms. Under conditions with the eyes open,
the number of significant correlations was greater, and correlations themselves were tighter than with the eyes closed. The
closest correlations of the estimates of personal anxiety with the SPDs of the beta rhythm were found in frontal and central
leads of both hemispheres and in parietal and occipital loci of the right hemisphere. Only a single case of correlation of
the alpha rhythm SPD with personal anxiety (negative correlation, a parietal lead in the left hemisphere) was found. At the
same time, rather numerous correlations of the alpha rhythm expression with an index congeneric to anxiety, the C factor by
the Cattel’s questionnaire (emotional stability/instability), were found. Thus, the intense beta EEG rhythm can be considered
an electrographic correlate of high situative and personal anxieties. At the same time, the alpha rhythm power correlates
with the emotional stability of the individual. We suppose that persons with a well-developed alpha rhythm are characterized
by active and stable functioning of the cerebral dopaminergic system; this simultaneously serves as a pre-requisite of high
emotional stability and social adaptability. 相似文献
93.
Results of karyological analysis of cells CHL V-79 RJK selected for resistance to ethidium bromide (EB) causing multidrug resistance (MDR) (line Vebr-5) were compared with the data of microfluorimetric determination of DNA content in individual chromosomes of the karyotype. The analysis was performed at the 11th and 88th passages. Karyotyping of Vebr-5 has shown the presence of an additional genetic material (ADM) in the form of homogenously or differentially stained regions (HSRs and DSRs, respectively) in two chromosomes (Z1 and Z6, loci 1 p29-31 and 1q26, respectively). HSRs in Z6, in the region of localization of the wild type of gene mdr, had unstable length and structure characteristic of morphological markers of amplification of genes of the family mdr. During long cultivation of Vebr-5 in the presence of EB (88 passages), the instability of HSRs in Z6 increased. Results of microfluorimetric analysis of Vebr-5 at the 11th passage have shown an increase in the DNA content not only in chromosomes Z1 and Z6 marked by HSRs, but also in three chromosomes (Z5, Z12 and Z13) that have no visual morphological changes. The corresponding analysis at the 88th passage has also revealed non-random changes in the DNA content in four more chromosomes: an increase in Z14, while a decrease in chromosomes 8, Z7, and Z9. A decrease of the DNA content in chromosomes is considered to be a result of a partial loss of genetic material, while its increase is a result of its translocation and (or) amplification. Coefficient of variation of the DNA content changes for large chromosomes amounted to about 9%. while for small chromosomes it is about 26%, which indicates that small chromosomes have greater potential for instability than the large ones. The data obtained not only confirm, but also enlarge the concept of directions and character of destabilization of the cell genetic apparatus in the process of neoplastic transformation due to the MDR acquisition by cells. 相似文献
94.
The assessment doses due to ingestion of 137Cs and 90Sr for the population suffering from the Chernobyl accident was performed on the basis of the new mechanistic ecological model
for assessment of radiological consequences of agricultural lands contamination (EMARC). The EMARC model allows estimation
of internal doses based on ecological factors influencing the contamination of foodstuff, for the post-accidental years in
the countries of the former Soviet Union. The EMARC model allows estimation of all quantities required in radiation hygiene
practice. For example, the proposed analytical method may be used for both retrospective dose reconstruction and prospective
estimates of annual dose and integrated “life-time” dose, for different age intervals. According to the EMARC model, estimated
reference “life-time” doses for adults are between 7 and 269 μSv kBq−1 m2 for 137Cs, and between 25 and 235 μSv kBq−1 m2 for 90Sr. Maximal doses were estimated for persons who were 3, 9 and 11 years old, at the time of the accident and these doses exceed
those for adults by a factors of 1, 5 for 90Sr, and 1.4 for 137Cs. 相似文献
95.
In 76 healthy persons (right-handed men and women), we recorded background EEG and event-related potentials from the C3 and C4 sites; tests were performed within the framework of an experimental situation requiring internal measuring-off of the time intervals. To limit the interval, the tested person had to push a button; he/she did not know the precise value of the interval, which was preset by the experimenter, and was informed only of the lower and upper limits of this interval, 17 to 23 sec. The person obtained information about the coincidence/noncoincidence of the measured-off and preset intervals via visual feedback; the respective signal was presented 2 sec after measuring-off had been completed. In the case where the intervals coincided with each other, the person should confirm this by pushing the button next time (confirming push). We characterized the parameters of the measured-off time interval by the following indices: (i) measuring-off efficacy (accuracy of fitting the preset interval), (ii) estimation tendency (measured-off interval/preset standard interval ratio), and (iii) coefficient of variation (CV) of the measured-off interval. Features of the subject's personality were estimated using Eysenck's (PEN) and Cattell's (16PF) questionnaires. We found correlations of the powers of the background EEG rhythms (beta1, beta2, and alpha/theta ratio) and characteristics of the measured-off time interval. In addition, we observed significant positive correlations between the estimation tendency and extraversion index and between CV of the interval and urge toward domination and protension indices. Negative correlations were observed between the measuring-off efficacy and protension (suspiciousness), between the estimation tendency and anxiety, and between the CV of the interval and age of the subjects. We support the conclusion that correlations between the patterns of EEG potentials, peculiarities of measuring-off of the time interval, and psychological features of the personality are to a noticeable extent mediated by the individual specificity of the neurodynamics. 相似文献
96.
N. M. Mikova N. V. Chesnokov E. V. Mazurova N. I. Pavlenko N. M. Ivanchenko 《Russian Journal of Bioorganic Chemistry》2016,42(7):741-747
Carbonization of betulin (betulinol) as an individual carbon precursor was studied in the temperature range of 400–800°C in the presence of KOH. Differential thermal analysis and IR spectroscopy were used to determine the influence of KOH on major structural changes and the chemical composition of betulin, which occur at 400–500°C. It was shown by scanning electron microscopy and BET analysis that KOH promoted the formation of a developed specific surface (SBET 1350–2100 m2/g) at temperatures of 600–800°C and had the greatest influence on the textural and adsorption properties of the resulting porous carbon adsorbents. It has been found that the formation of microporous carbon materials with a pore size of 1.92 nm and a specific micropore surface area of 1275 m2/g is possible upon the activation of betulin with KOH at 800°C. Betulin may be proposed to control the porosity of the carbon carriers derived from birch wood. 相似文献
97.
I. N. Sheremetyeva I. V. Kartavtseva M. V. Pavlenko T. V. Vasiljeva V. P. Korablev 《Biology Bulletin》2017,44(4):391-400
The genetic variability of the greater long-tailed hamster Tscherskia triton of the peripheral population of the southern Russian Far East is evaluated compared to the central populations of China based on the nucleotide sequences of the control region of mitochondrial DNA. The high genetic diversity of the population of the southern part of Russian Far East is established, which does not confirm a hypothesis on reduction of the diversity in the peripheral populations. The presence of three phylogroups is discovered: one within Russia (“northern”) and two within China (“central” and “southern”). A deletion, absent in other taxonomically distant groups of the Old and New World and acquired by the greater long-tailed hamster over the course of its evolutionary history, is present in certain populations of this species. A preliminary hypothesis, according to which the contemporary structure of this species is determined not only by topographical and climatic events, but by human activity as well, is formulated. 相似文献
98.
Banentskaia NV Amvros'ev AP Pavlenko VS 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2000,40(3):250-253
The prolonged irradiation with 1.0 Gy dose in prenatal and early postnatal periods of development of rats leads to the disturbance in the rate of follicular growth, the reduction of their pool, mainly the pool of young forms of oocytes. Processes of degeneration and destruction occur and develop in the ovary of both the irradiated rats and their first progeny. 相似文献
99.
O.?I.?KolotilovaEmail author V.?B.?Pavlenko A.?M.?Kulichenko I.?O.?Korenyuk Yu.?O.?Fokina 《Neurophysiology》2005,37(3):205-212
In experiments on five awake cats, we studied the effects of bemitil, a drug possessing psychostimulatory, antidepressive,
and actoprotector properties (peroral introduction, 50 mg/kg), on the activity of neurons of the aminergic cerebral systems.
Eleven noradrenergic (NA-ergic) neurons of the locus coeruleus (LC) and 11 serotonergic (ST-ergic) neurons of the nuclei raphe (NR) were examined. A control experimental series was carried out on 8 NA-ergic neurons of the LC and 8 ST-ergic neurons
of the NR. Bemitil was found to exert opposite effects on the impulse activity of NA-ergic and ST-ergic brainstem neurons;
it suppressed impulsation of LC neurons and increased the spiking frequency of NR neurons within certain time intervals after
its introduction. Analysis of EEG showed that bemitil decreased the spectral power of the delta and theta activities, which
was accompanied by behavioral relaxation.
Neirofiziologiya/Neurophysiology, Vol. 37, No. 3, pp. 235–243, May–June, 2005. 相似文献
100.
Complete nucleotide sequences of bovine alpha S2- and beta-casein cDNAs: comparisons with related sequences in other species 总被引:2,自引:0,他引:2
Stewart AF; Bonsing J; Beattie CW; Shah F; Willis IM; Mackinlay AG 《Molecular biology and evolution》1987,4(3):231-241
The nucleotide sequences corresponding to bovine alpha S2- and beta- casein
mRNAs have been determined by cDNA analysis. Both sequences appear to be
complete at their 5' ends. The nucleotide sequence of alpha S2-casein, when
compared with the corresponding cavine A sequence, helps to define the
boundaries of a large amino acid repeat (approximately 80 residues) whereas
comparisons with the nucleotide sequences of rat gamma- and mouse
epsilon-casein mRNAs also reveal extensive sequence similarities. An
alignment of these four sequences shows that the divergence of their
translated regions has been characterized by the duplication and deletion
of discrete segments of sequence that probably correspond to exons. A high
degree of nucleotide substitution is also found when the four sequences are
compared, except for well-conserved leader-peptide and phosphorylation-site
sequences and, to a lesser extent, the 5'-untranslated regions. Similar
comparison of the bovine and rat beta-caseins shows that their divergence
has involved a high rate of nucleotide substitution but that no major
insertions or deletions of sequence have occurred. The several splice sites
that have veen defined in the rat beta-casein gene are likely to have been
conserved in the bovine. The contrasting evolutionary histories of the
alpha- and beta-casein coding sequences correlate with the distinctive
functions of these proteins in the casein micelle system in milk.
相似文献