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1.
E M Nikulina O V Trapezov N K Popova 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1985,35(6):1142-1146
Content of dopamine in the striatum; of serotonin, 5-hydroxyindolacetic acid and noradrenaline in the hypothalamus, striatum and midbrain was studied in three groups of minks from population of an animal farm, differing by their reaction to humans (cowardly, calm, aggressive). The reaction to humans was estimated by a system of marks at the attempt to catch the mink with a mitten. Aggressive animals had a lowered level of serotonin in the hypothalamus and striatum, a lesser content of serotonin metabolite--5-hydroxyindolacetic acid in the striatum. Minks of different groups did not differ by noradrenaline content, but dopamine level in the striatum of cowardly minks was higher than in calm and aggressive animals. Conclusion is made that polymorphism of behaviour corresponds to polymorphism of the state of monoaminergic systems. 相似文献
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V I Popova L M Va?ner I I Gorshkova O A Gromova V V Liakhovich 《Biokhimii?a (Moscow, Russia)》1985,50(1):53-62
The previously described, iodine-labeled alkylating stable nitroxyl radicals located at different distances between the N-O. group and the iodine atom were used for a comparative study of the structure of microsomal cytochromes P-450 and P-448 active centers. The radicals were shown to change the optical spectra of Fe3+ located in the active site of the enzyme that are similar to those induced by cytochrome P-450 substrates. Some differences in the type of the radicals binding to control, phenobarbital- and 3-methylcholanthrene-induced microsomes were revealed. The alkylating radical substrate analogs covalently bound to microsomal cytochrome P-450 in the vicinity of the active center, resulting in the inhibition of oxidation of type I and II substrates (e. g., aniline and naphthalene). The value of the spectral binding constant (Ks) for naphthalene in the presence of the radical covalently bound to the cytochrome P-450 active center showed a tendency to increase. Using the ESR technique, the interaction between Fe3+ and the radical localized in the active site of cytochrome P-450 was demonstrated. The contribution of Fe3+ to the relaxation of the radicals covalently bound to cytochrome P-450 was evaluated from the values of the spin label ESR spectra saturation curves at 77K. The distances between the N-O. group of these radicals and Fe3+ in the enzyme active center for the three types of microsomes were determined. The data obtained point to structural peculiarities of the active center of cytochrome P-450, depending on the microsomal type. 相似文献
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Using ethnographic data collected in a second grade classroom over the course of a school year, this paper describes the ways in which one school's discourse of liberalism is deleteriously deployed. We view the school's discipline creed as emblematic of the school's liberal curriculum, and interrogate the effects on four African American boys in the classroom when the school enacts this creed. Despite the agency that these boys obviously had, they were unable to control the ways in which they were placed at a structural disadvantage and manipulated by a system far more powerful than they were. The results were that these four boys suffered. Not only did the intended liberal curriculum fail to be translated fully into the enacted curriculum, the liberal underpinnings of this curriculum precluded teachers and students from taking any critical stance. 相似文献
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A review of experimental data documenting that domestication of animals is associated with hereditary reorganization of neuro-endocrine mechanisms, responsible for basic processes of ontogeny, is presented. The data demonstrated changes in gonadal and pituitary-adrenal systems in domesticated animals. Analysis of evidence that selection for low aggressiveness towards man is, in fact, the selection for definite activity of brain neurotransmitters regulating aggressive behaviour and emotional stress response has been carried out. Supposed role of modifications in the mechanisms of domestication is discussed. 相似文献
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In vivo effect of abscisic acid (ABA) on photosynthetic oxygen evolution was investigated in barley chloroplasts. The most important kinetic parameters of O2-producing reactions were changed. The results show inhibition of the O2-flash yields at ABA concentrations of 10 mol/l and 100 mol/l and an increase in the degree of damping of the oscillations. ABA has a marked effect on the distribution of the oxygenevolving centers in S0 and S1 states and on sum of the centers (S0+S1) estimated according to the Kok model. In addition, the amplitude and the shape of the initial oxygen burst under continuous illumination are also significantly altered. At a concentration of 100 mol/l, ABA strongly inhibits Hill reaction activity measured by DCPIP reduction. The results cannot be explained by the hypothesis of socalled stomata effect. On the other hand, no effects were observed on the investigated parameters in experiments involving ABA applied in vitro to isolated chloroplasts. It is hypothesized that ABA disrupts the granal chloroplasts structure and raises the degree of participation of the cooperative mechanism of O2-evolution connected with the functioning of PS II centers in the stroma situated thylakoids.Abbreviations DCPIP
2,6-Dichlorophenolindophenol
- DCMU
3-(3,4-dichlorophenil)-1,1-dimethylurea
- HEPES
N-2-Hydroxyethylpiperazine-N-2-ethane sulfonic acid
- PSII
photosystem II
- RubisCO
Ribulose-1,5-bis-phosphate carboxylase-oxygenase 相似文献