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111.
112.
The electrophysiological correlates of major depression disorder with anxious distress in patients of different age groups have been investigated. The spectral characteristics of 19-channel background EEG were analyzed and the power spectra recorded with the eyes closed vs. eyes open in 64 patients with anxiety–depressive disorder and in 194 healthy subjects were compared. The subjects were divided into the two age groups: 18–39 and 40–76 years old. The spectral parameters were calculated for 5 main EEG frequency bands: θ (4–8 Hz), α (8–12 Hz), β1 (12–20 Hz), β2 (20–30 Hz), and γ (30–40 Hz). The most statistically significant differences between the groups were found in the α, β, and γ bands. Lower values of spectral power of the α rhythm in occipital areas and the higher values of spectral power of the β and γ rhythms in the frontocentral region were recorded in the group of 18-to-39-year-old patients with the eyes closed. Higher values of spectral power of the β rhythm in the fronto-central region and in the left temporal lobe were recorded in the group of 40-to-76-year-old patients with both the eyes closed and the eyes open. The higher β-activity in the fronto-central regions in both groups of patients may be caused by increased excitability of the cerebral cortex and decreased activity of inhibitory processes. Increased activation of the left temporal lobe in older subjects is probably associated with the severity of anxiety symptoms and may be a distinctive marker of mixed anxiety and depressive disorder. The lower values of α-power revealed only in the group of younger subjects are probably associated with age-related reorganization of EEG in older subjects.  相似文献   
113.
Pink salmon Oncorhynchus gorbuscha from odd and even year generations in rivers of Sakhalin Island, Kuril Island, Kamchatka Peninsula, and Alaska were investigated with five informative restriction endonucleases for mtDNA variation. The odd and even generations from the same rivers of South Sakhalin differed greatly. The time of divergence between the two broodlines was estimated at 0.9-1.1 Myr. The variability of mtDNA in odd year generations was higher than in even year generations and may have been due to' founder' and/or' bottleneck' effects. The differences among river populations within the Sakhalin region in 1991-1993 were not significant and this confirms the highly migratory nature of pink compared with other Pacific salmon. The mtDNA samples revealed statistically significant differences between regions. The northern populations (Kamchatka, Alaska) were less diverse in number and frequency of haplotypes than the southern populations (Sakhalin). This suggests that pink salmon originated in the Sakhalin-Kuril region and that a founder effect during the spread of this species may have restricted the mtDNA variability in other regions.  相似文献   
114.
SYNOPSIS. Deprived of vitamin B12, Euglena gracilis strain Z ceases to divide which we believe to be a function of the light regime: division inhibition occurs more quickly in continuous light than in alternating (6L : 6D) light and not at all in total darkness. This phenomenon is dependent on the carbon source; cells grown in glutamate-malate medium do not divide regardless of the culture conditions while dl -lactate as carbon source permits growth in darkness in the absence of B12. Conditions which lead to an increased O2 or decreased CO2 tension in the medium, such as agitation in darkness or incubation in red or white light, result in inhibition of division. This inhibition can be reversed by re-transferring the cells to still culture in the dark or, in the case of light-induced blockage, by the addition of DCMU.  相似文献   
115.
Comparative studies have been done of the interactions of some coenzyme analogues with the apoenzymes of γ-cystathionase (EC 4.2.1.15) from rat liver and serine sulphhydratase (EC 4.2.1.22) from chicken liver — pyridoxal-phosphate-dependent enzymes catalysing reactions of H2S release from L-cystein via α,β-elimination and β-substitution, respectively. It was found that minor modifications (substitutions) in the structure of pyridoxal-5′-phosphate (pyridoxal-P; PLP) result in marked lowering of affinity of the analogues for the apoenzymes. Considerable differences were observed between the various apoenzymes in regard to the mode of their interaction with the pyridoxal-P analogues used.  相似文献   
116.
The influence of electromagnetic radiation of extremely high frequencies in the noise mode on the level of the activity of proand antioxidant systems in a model of skin-flap ischemia was studied in vivo. Rats of the Wistar line were used in this work. The cutaneous reflex projection field of the animals was exposed once a day for 7 days in the post-operative period to electromagnetic radiation of an extremely high frequency in the range from 53.57 to 78.33 GHz with a dose of 1.2 mJ in the noise mode. The dynamics of proand antioxidant protection were compared to those of intact animals that were not irradiated. Using data on induced biochemiluminescence and estimation of malondialdehyde activity it was shown that irradiation in a course mode contributed to a decrease in the intensity of lipid peroxidation. In parallel we observed an increase in the total antioxidant reserves of blood and the activity of bioradical protection enzymes. Our findings suggest that electromagnetic radiation at extremely high frequencies in a noise mode has a regulatory impact on the state of proand antioxidant systems of the body; this can be used for the correction of postoperative ischemic disorders and the restoration of disturbed homeostasis.  相似文献   
117.
Thawing in the water bath is often considered as a standard procedure. The thermal history of samples thawed in this way is poorly controlled, but cryopreservation and banking of cell-based products require standardization, automation and safety of all the technological stages including thawing. The programmable freezers allow implementation of the controlled cooling as well as the controlled thawing. As the cell damage occurs during the phase transformation that takes place in the cryoprotectant medium in the process of freezing–thawing, the choice of warming rates within the temperature intervals of transformations is very important. The goal of the study was to investigate the influence of warming rates within the intervals of the phase transformations in the DMSO-based cryoprotectant medium on the cell recovery and to develop a cryopreservation protocol with controlled cooling and warming rates. The temperature intervals of phase transformations such as melting of the eutectic mixture of the cryoprotectant solution (MEMCS), melting of the eutectic salt solution (MESS), melting of the main ice mass (MMIM), recrystallization before MEMCS, recrystallization before MESS and recrystallization before MMIM were determined by thermo-mechanical analysis. The biological experiments were performed on the rat testicular interstitial cells (TIC). The highest levels of the cell recovery and metabolic activity after cryopreservation were obtained using the protocol with the high (20 °C/min) warming rate in the temperature intervals of crystallization of the eutectics as well as recrystallizations and the low (1 °C/min) warming rate in the temperature intervals of melting of the eutectics as well as MMIM. The total cell recovery was 65.3 ± 2.1 %, the recovery of the 3-beta-HSD-positive (Leydig) cells was 82.9 ± 1.8 %, the MTT staining was 32.5 ± 0.9 % versus 42.1 ± 1.7 %; 57.4 ± 2.1 % and 24.0 ± 1.1 % respectively, when compared to the thawing in the water bath.  相似文献   
118.
Objectives:The aim of this study was to assess the quantitative composition of muscle and adipose tissue in type 2 diabetes mellitus (T2DM) patients on the basis of dual-energy X-ray absorptiometry for the diagnosis of obesity and sarcopenia.Methods:Dual-energy X-ray absorptiometry was administered to 50 patients with T2DM. Evaluation of the composition of muscle and adipose tissue was performed.Results:The median of Appendicular Lean Mass Index (ALMI) in the general group was 8.04 [7.32; 8.97]. In general, there was a decrease in the appendicular muscle mass with increasing age. According to the results of T-score ALMI and Z-score ALMI, we did not identify patients with sarcopenia. However, the calculation of the T- and Z-criteria, adjusted for fat mass, led to a significant decrease of these parameters and in 98.0% it was possible to identify patients who meet the criteria of sarcopenia.Conclusion:We did not detect patients with sarcopenia on the basis of ALMI, T-ALMI. After revision of these criteria for fat mass, almost all patients started to meet the criteria of sarcopenia (98.0%).  相似文献   
119.
Summary The effect of exogenous KNO3, the terminal acceptor of electrons in oxygen-free medium, on mitochondrial ultrastructure and on the growth rate of 4-day-old rice coleoptiles under strictly anoxic conditions was studied. Exogenous nitrate (10 mM) did not exert any significant effect on the growth rate of coleoptiles of intact seedlings compared to their growth in KNO3-free medium. Anaerobic incubation of detached coleoptiles in KNO3-free medium for 48 h resulted in the complete destruction of mitochondrial and other cell membranes. In the presence of KNO3, no mitochondrial-membrane destruction was observed even after 48 h anoxia although the mitochondrial ultrastructure was modifed. Cristae were arranged in parallel rows and elongated dumbbell-shaped mitochondria appeared in some cells. The data obtained indicate a protective role of exogenous nitrate as electron acceptors in oxygen-free medium. The results of the present investigation are discussed and compared with reports of either markedly damaging or favorable effects of exogenous nitrate on the growth, metabolism, and energetics of rice and other plants under hypoxic and anoxic conditions.  相似文献   
120.
The analysis of the micromycete complexes of oligotrophic peat deposits in the Vasyugan Marsh by direct count and culture methods showed that micromycete carbon comprises no more than 3% of the total peat carbon and that the microscopic fungal biomass varies from 2 to 13 tons/hectare, depending on the season and the peat deposit thickness. Fungal spores were found in all layers of the peat deposits, whereas the mycelium was found only in the active peat layer. The high abundance of eukaryotic cells in the peats was due to the presence of yeastlike cells rather than fungal spores. Analyses by culture methods showed that micromycetes were present in all peat layers and that their abundance tended to decrease with depth, except for yeasts, which were uniformly distributed in a vertical direction. The micromycete complexes of the peat deposits were similar in their diversity and abundance of dominant species but differed in the composition of minor species. Peat yeasts were dominated by ascomycetes.  相似文献   
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