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11.
Multiparametric comparative analysis of spatial organization of EEG was carried out in 137 alcoholics and 131 heroin addicts. Common and different deviations from normal EEG (105 control subjects) were found. Global alterations of EEG spatial organization were observed in drug addicts (as compared to alcoholics). Such changes characterized increasing synchronizing effects of mesolimbic and brainstem structures on the brain cortex. The ethanol effects were more specific and asymmetric. Changes in EEG spectral-coherence characteristics were revealed in all frequency band, however, maximal changes took place in the high-frequency theta in drug addicts and in narrow-frequency alpha subranges in alcoholics. Different effects on the high-frequency EEG component (19.00-21.25 Hz) and information-energy index (coherence-to-spectral power ratio) suggest the difference influence of ethanol and heroin on emotional-motivational and cognitive processes as well as the level of consciousness. The obtained data on EEG discrimination of alcoholism and drug addiction (the inverse problem solution) on the basis of "specific" EEG patterns appear to have considerable promise in development of systems of occupational selection.  相似文献   
12.
Subjects performed intense exercises in a teadbahn under conditions of high ambient temperature and humidity. Spatial characteristics of the EEG were estimated. The information value of the time course of the combined index, characteristics of spatial synchronization and entropy of cortical biopotentials as a test for brain reaction to a load and recovery of its functional state was shown. The significance of non-linear relations between brain potentials in the activation of the adaptive and compensation processes was mentioned.  相似文献   
13.
The alpha3 fucosyltransferase, FucT-VII, is one of the key glycosyltransferases involved in the biosynthesis of the sialyl Lewis X (sLex) antigen on human leukocytes. The sialyl Lewis X antigen (NeuAcalpha(2-3)Galbeta(1-4)[Fucalpha(1-3)]GlcNAc-R) is an essential component of the recruitment of leukocytes to sites of inflammation, mediating the primary interaction between circulating leukocytes and activated endothelium. In order to characterize the enzymatic properties of the leukocyte alpha3 fucosyltransferase FucT-VII, the enzyme has been expressed in Trichoplusia ni insect cells. The enzyme is capable of synthesizing both sLexand sialyl-dimeric-Lexstructures in vitro , from 3'-sialyl-lacNAc and VIM-2 structures, respectively, with only low levels of fucose transfer observed to neutral or 3'-sulfated acceptors. Studies using fucosylated NeuAcalpha(2-3)-(Galbeta(1- 4)GlcNAc)3-Me acceptors demonstrate that FucT-VII is able to synthesize both di-fucosylated and tri-fucosylated structures from mono- fucosylated precursors, but preferentially fucosylates the distal GlcNAc within a polylactosamine chain. Furthermore, the rate of fucosylation of the internal GlcNAc residues is reduced once fucose has been added to the distal GlcNAc. These results indicate that FucT-VII is capable of generating complex selectin ligands, in vitro , however the order of fucose addition to the lactosamine chain affects the rate of selectin ligand synthesis.   相似文献   
14.

Objective

To examine the association between the 5-HTTLPR polymorphism of the serotonin transporter (SLC6A4) gene, combat exposure, and posttraumatic stress disorder (PTSD) diagnosis and among two samples of combat-exposed veterans.

Method

The first sample included 550 non-Hispanic Black (NHB) combat-exposed veterans. The second sample included 555 non-Hispanic White (NHW) combat-exposed veterans. Participants were genotyped for the 5-HTTLPR/rs25531 variants of the SLC6A4 gene. A structured clinical interview was used to diagnose PTSD. Combat and civilian trauma exposure were assessed with validated self-report instruments. Logistic regression was used to test for main effects of 5-HTTLPR on PTSD diagnosis as well as gene x environment (GxE) interactions after adjusting for sex, ancestry proportion scores, civilian trauma exposure, and combat exposure.

Results

Within the NHB sample, a significant additive effect was observed for 5-HTTLPR (OR = 1.502, p = .0025), such that the odds of having a current diagnosis of PTSD increased by 1.502 for each additional S’ allele. No evidence for an association between 5-HTTLPR and PTSD was observed in the NHW sample. In addition, no evidence for combat x 5-HTTLPR effects were observed in either sample.

Conclusion

The present study suggests that there may be an association between 5-HTTLPR genotype and PTSD diagnosis among NHB veterans; however, no evidence for the hypothesized 5-HTTLPR x combat interaction was found.  相似文献   
15.
In experiments on 24 anesthetized rats with preserved spontaneous respiration, we first recorded the volley impulse activity of neurons (n = 30) in the brainstem A5 zone, which was induced by periodical stretchings of the forelimb flexors and hindlimb extensors. The frequency of action potentials in such volleys was, on average, 99.7 ± 19.6 sec−1. In the course of this kinesthetic stimulation, along with the activation of “proprioceptive” neurons of the A5 zone, we observed transitory drops in the arterial pressure and increases first recorded the activity of baroceptive neurons in subpial parts of the A5 zone (n = 4); the frequency of their background impulsation was, on average, 25.1 ± 0.8 sec−1. This activity in all cases was transitorily suppressed both upon increases of the blood pressure caused by constriction of the carotid arteries or nociceptive tail stimulation, as well as upon stretching of skeletal muscles. Therefore, we first obtained direct proof that neuronal systems of the A5 zone are involved in integration of visceral and somatic proprioceptive afferent influences. We hypothesize that the physiological role of this mechanism of integration of somatic and visceral information at the level of the A5 zone is directed toward lowering of the arterial pressure and intensification of respiration within the period of intensified motor activity. This mechanism is based on the interaction between “proprioceptive,” baroceptive, and, perhaps, multiceptive neurons within the A5 zone. Neirofiziologiya/Neurophysiology, Vol. 39, No. 6, pp. 443–452, November–December, 2007.  相似文献   
16.
Genome instability transmission in offspring was analyzed in order to evaluate the risk of delayed genetic effects of exposure in 95 family triplets in which only fathers experienced prolonged occupational radiation exposure. The mean total preconceptive absorbed dose (TPAD) of external gamma radiation in the paternal gonads was 1.65 ± 0.080 Gy (dose range of 0.57–5.70 Gy), and the mean TPAD of internal alpha radiation from incorporated plutonium-239 in the gonads was 0.0015 ± 0.0003 Gy (dose range 0.000–0.015 Gy). The control group consisted of 50 family triplets in which parents were not occupationally exposed. The mutation process was studied using PCR based on hypervariable minisatellite marker CEB1 (chromosome 2, 2q37.3). The paternal type of inheritance of mutations for minisatellite CEB1 was found in 80% of cases. The analysis revealed a statistically significant increase in minisatellite CEB1 mutations in the common group of families in which fathers experienced prolonged occupational radiation exposure and in the group of families in which fathers were exposed to radiation in a dosage range of 0.5–1.0 Gy as compared to the control, reaching a significance level of p = 0.109 and p = 0.058, respectively. The dose threshold of mutation detection in the offspring of Mayak PA workers was estimated.  相似文献   
17.
1. An artificial glass substratum was incubated in the River Danube for a period of 28 days in order to detect the sequential colonization of microorganisms.
2. Light and fluorescent microscopy showed that microalgae and the picoalgal fraction on the slides increased rapidly over the first 2 weeks of colonization. Diatoms were numerically the most abundant component of the periphyton and their species richness and diversity increased rapidly in the early phase of colonization whereas diversity subsequently increased moderately.
3. Evenness of the diatom community was initially high, lower in the intermediate phase and again higher later on. Succession involving early, intermediate and late colonizer species was observed. Community composition during the first 5 days of colonization was very different from later stages whereas there were only minor changes subsequently.
4. Molecular community analysis by means of terminal restriction fragment length polymorphism analysis of PCR amplified 16S rRNA and 18S rRNA genes pointed to even larger differences between the composition of samples obtained early and late in the period.
5. The number of 18S rRNA and 16S rRNA terminal restriction fragments (T-RF-s) was variable over the colonization period and the fragment patterns of both the bacterial and eukaryotic portion of the microbial community were variable, with most T-RF-s unique to a single sample, suggesting a wide diversity and dynamic properties of periphytic organisms.  相似文献   
18.
19.
In an inbred low-activity (LA) strain of Drosophila melanogaster with a low level of fitness and a complex of inadaptive characters, in situ hybridization reveals an invariant pattern of distribution of three copia-like elements (mdg-1, mdg-3, and copia). Rare, spontaneous, multiple transpositions of mobile elements in the LA strain were shown to be coupled with a drastic increase of fitness. A changed pattern of various types of mobile elements was also observed on selecting the LA strain for higher fitness. High-fitness strains show transpositions of mobile elements to definite chromosomal sites ("hot spots"). Concerted changes in the location of three different mobile elements were found to be coupled with an increase of fitness. The mdg-1 distribution patterns were also examined in two low-fitness strains independently selected from the high-fitness ones. Fitness decrease was accompanied by mdg-1 excision from the hot spots of their location usually detected in the high-fitness strains. The results suggest the existence of a system of adaptive transpositions of mobile elements that takes part in fitness control.   相似文献   
20.
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