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31.
The EEG power in the β1, β2, and γ frequency bands during reading according to the method of “self-regulatory utterance” was compared in subjects reading
aloud emotionally neutral business texts related to an unknown field of activity, fiction texts with clear positive or negative
valences or personally important autobiographic texts with similar emotional valences. Two groups of subjects participated
in the study: students training to be actors (N = 22) and students with other specializations (N = 23). We observed higher values of the EEG power in the γ (30–40 Hz) and β2 (18.5–29.5 Hz) frequency bands when comparing the states during reading of emotionally positive and emotionally negative
fiction texts and personally important texts. These data are similar to our previous studies with the use of techniques that
apply internal induction of positive or negative emotions without speech, in different groups of subjects. Internal induction
of positive emotions was associated with an increase in the EEG power in these bands compared to the performance of an emotionally
neutral task, whereas induction of negative emotions resulted in a decrease in the EEG power. 相似文献
32.
Group 1 (N = 30) and Group 2 (N = 22) of healthy volunteers participated in the experiment. In both groups, the EEG was recorded in the state of rest with
the eyes closed (REC); at rest with eyes open (REO); and during passively watching TV channel noises (white noise). EEG was
also recorded in the state of forced visual attention: when counting colored symbols appearing on the screen (group 1) and
when searching for an image of a real object in the noise (group 2). The averaged values of EEG power in each derivation were
calculated for every subject and for each state in the Δ, θ, α1, α2, β1, β2, and γ frequency bands. The results demonstrate that the exposure to unstructured noninformative video noise may lead to
significant changes in the EEG power in various frequency bands, with the most prominent changes taking place in the α2 band. These changes are topically wide, reflecting systemic changes in the corresponding brain mechanisms, but are much less
intense compared to the difference between the states of rest with the eyes open and closed. 相似文献
33.
Modality-specific and supramodal EEG components that are related to the reorientation of involuntary anticipatory attention
from the internal to the external type were studied by comparing the unblocking of the visual and acoustic channels. EEG recording
was performed while subjects were at rest with their eyes open, with their eyes closed, or with their eyes closed while using
noise-protective earplugs. The means of both the EEG power in each of the derivations and EEG coherence in each of the derivation
pairs were calculated for every subject and for each of the states. The estimations have been done for the Δ, θ, α1, α2, β1, β2, and γ frequency bands. The obtained data proved the hypothesis on the manifestation of both modality-specific and supramodal
components in the brain mechanisms of involuntary anticipatory attention. These results are of interest for discussion on
the degree of similarity and distinction between the systemic supports of the brain mechanisms of visual and auditory attention. 相似文献
34.
Heavy metal cations permeate the TRPV6 epithelial cation channel 总被引:1,自引:0,他引:1
TRPV6 belongs to the vanilloid family of the transient receptor potential channel (TRP) superfamily. This calcium-selective channel is highly expressed in the duodenum and the placenta, being responsible for calcium absorption in the body and fetus. Previous observations have suggested that TRPV6 is not only permeable to calcium but also to other divalent cations in epithelial tissues. In this study, we tested whether TRPV6 is indeed also permeable to cations such as zinc and cadmium. We found that the basal intracellular calcium concentration was higher in HEK293 cells transfected with hTRPV6 than in non-transfected cells, and that this difference almost disappeared in nominally calcium-free solution. Live cell imaging experiments with Fura-2 and NewPort Green DCF showed that overexpression of human TRPV6 increased the permeability for Ca(2+), Ba(2+), Sr(2+), Mn(2+), Zn(2+), Cd(2+), and interestingly also for La(3+) and Gd(3+). These results were confirmed using the patch clamp technique. (45)Ca uptake experiments showed that cadmium, lanthanum and gadolinium were also highly efficient inhibitors of TRPV6-mediated calcium influx at higher micromolar concentrations. Our results suggest that TRPV6 is not only involved in calcium transport but also in the transport of other divalent cations, including heavy metal ions, which may have toxicological implications. 相似文献
35.
Event-related brain potentials when conjugating Russian verbs: The modularity of language procedures
S. G. Danko J. A. Boytsova M. L. Solovjeva T. V. Chernigovskaya S. V. Medvedev 《Human physiology》2014,40(3):237-243
Within the alternative concepts of “two-system” and “single-system” language models, brain mechanisms for the generation of regular and irregular forms of Russian verbs have been studied. The evoked EEG activity was recorded in 19 channels with random alternation of different speech-morphology operations. The infinitives of imperfective verbs that belong either to the productive group (conventionally, the default, or regular, class) or to the unproductive group (conventionally, the irregular class) were presented to healthy subjects. The subjects were to produce the first-person present-time forms of these verbs. The results of the analysis of the event-related potentials (ERPs) of 22 subjects are presented. Statistically valid ERP amplitude distinctions between the verb groups are found only in latencies of 600–850 ms in the central and parietal zones of the cortex. The peak values of the irregular-verb potentials are negative in this region in relation to the peak values of the regular-verb potentials. The findings are interpreted as the effect of various complexities of mental work with verbs of different groups and do not support the hypothesis of the universality of the two-system brain mechanism for processing regular and irregular language phenomena. 相似文献
36.
Dejan Krsmanovic Igor Koncar Dejan Petrovic Danko Milasinovic Lazar Davidovic Nenad Filipovic 《Computer methods in biomechanics and biomedical engineering》2014,17(9):1012-1020
The objective of this study was to determine the orientation and magnitude of maximal displacement forces (DFs) in the thoracic aortic aneurysm endograft (TAA endograft) in three-dimensional (3D) space. Theoretical computer model representing the anatomically worst-case scenario with respect to DF magnitude was used to calculate the magnitude and orientation of maximal DF. A patient-specific anatomical computer model of typically seen, average size anatomy was used to analyse the progression of DF throughout the cardiac cycle. Maximal DFs were 35.01 and 37.32 N in standing and supine position, respectively, in 46-mm diameter TAA graft with 90° bend. A patient-specific model shows that a maximal DF magnitude is achieved at the peak systolic flow. In both models, the orientation of the DF vector was perpendicular to the greater curvature of the aorta, with upward (cranial) and sideways components. The effect of shearing force on the total DF that acts on the TAA endograft was found negligible due to the several orders of magnitude stronger contribution of pressure forces to the total DF relative to the wall shear stress contribution, resulting in aortic diameters and angulation being the main drivers of DF. It was discovered that the TAA endografts can be subjected to much stronger DF than previously suspected. The magnitude of maximal DF in thoracic aorta in the worst-case scenario could be as high as 35.01 N (standing) and 37.32 N (supine). This new information should be used in the process of designing new generations of TAA endografts with better migration resistance properties. 相似文献
37.
The effects of dantrolene, which is a known muscle relaxant, on Ca2+ release from the isolated sarcoplasmic reticulum induced by several different methods [1) addition of caffeine, (2) Ca2+ jump, and (3) membrane-depolarization produced by choline chloride replacement of potassium gluconate) were investigated. Dantrolene inhibited caffeine-induced Ca2+ release with C1/2 = 2.5 microM, whereas there was no effect on Ca2+ release induced by a Ca2+ jump. The amount of Ca2+ released by depolarization was reduced if Ca2+ release was triggered in an earlier phase of the steady state of Ca2+ uptake (time elapsed between the addition of ATP and the triggering of Ca2+ release, tATP less than 4 min); while, if triggered in a latter phase (tATP greater than 4 min) dantrolene enhanced depolarization-induced Ca2+ release. C1/2 for the inhibition and that for enhancement of depolarization-induced Ca2+ release were 1.0 and 0.3 microM, respectively. These results suggest that dantrolene affects several different steps of the mechanism by which Ca2+ release is triggered. The sarcoplasmic reticulum and T-tubule membrane fractions had 7.9 nmol dantrolene-binding sites/mg (Kassoc = 1.0 X 10(5) M-1) and 21.0 nmol/mg (Kassoc = 1.1 X 10(5) M-1), respectively. The time-course of dantrolene binding to sarcoplasmic reticulum was monophasic, while that to T-tubules was biphasic. 相似文献
38.
Quantitative statistical estimates of changes in ultraslow phasic electrical activity of the brain (in the range 0.05–0.5 Hz) and the EEG (1.5–50 Hz) with time were compared in the basic (reference) states of quiet wakefulness with the eyes open and closed (EO and EC, respectively). In both states, the changes in the power and coherence of ultraslow phasic activity and the EEG had similar trends; however, the topographic patterns of the changes were different. The obtained data confirm the assumption on different structural and functional bases of the EEG and ultraslow phasic activity of the brain and indicate polysystemic differences between the EO and EC states. 相似文献
39.
Danko J. Brncic 《Molecular & general genetics : MGG》1953,85(1):1-11
Summary Brazilian populations of D. guaramunu (Dobzhansky and Pavan, 1943) exhibit a high degree of chromosomal polymorphism. At least 19 inversions are known.These inversions have been found in the four long autosomes, while the X chromosome and the dot-shaped chromosomes do not show any variation in the gene sequences. Among the autosomes, the fourth chromosome seems to be the most variable one, 13 out of 19 inversions here reported being localized in it.With the aid of crosses to a homozygous Standard strain, it has been possible to establish schematically the phylogenetic relationships between the different gene arrangements.With 7 figures in the text and 1 plate.Research Fellow of the University of São Paulo, Brazil, in 1951. 相似文献
40.
Involvement of Coenzyme M during Aerobic Biodegradation of Vinyl Chloride and Ethene by Pseudomonas putida Strain AJ and Ochrobactrum sp. Strain TD 总被引:1,自引:0,他引:1
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Anthony S. Danko Christopher A. Saski Jeffrey P. Tomkins David L. Freedman 《Applied microbiology》2006,72(5):3756-3758
The involvement of coenzyme M in aerobic biodegradation of vinyl chloride and ethene in Pseudomonas putida strain AJ and Ochrobactrum sp. strain TD was demonstrated using PCR, hybridization, and enzyme assays. The results of this study extend the range of eubacteria known to use epoxyalkane:coenzyme M transferase. 相似文献