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A light- and electron-microscopic study was made of changes in the structure of neurons and synapses in the caudate nucleus of rats 2 and 3 days after motor excitation induced by amphetamine (10 mg/kg body weight). Electron-microscopic investigations 2 days after amphetamine excitation showed predominance of synthesis over utilization of the intracellular organelles in the neurons of the caudate nucleus; the latter process took place, moreover, in the direction from nucleus to periphery of the cell body. A statistically significant increase in the mean area of cross-section of the nuclei and bodies of the neurons and in the number of impregnated spines per unit length of the dendrites was found. The ultrastructure of the neurons was largely restored to normal after 3 days although the mean area of cross section of the bodies and nuclei of the neurons had not yet reached its initial values. There was virtually no difference in the number of impregnated spines of the dendrites compared with the control, but electron microscopy revealed many synaptic vesicles in the axon terminals.  相似文献   
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Further investigations on the effect of different stress factors on the stability of intracellular membranes were carried out. Large granule fractions derived from livers of sleep-deprived and dehydrated rats and subjected to preincubation at 37 degrees and pH 5 were shown to release latent acid phosphatase with a delayed rate indicating an increased lysosomal stability towards acid media conditioning. Lysosomes of such animals, however, were found to be more sensitive to mechanical treatments (homogenization procedure in this case) than that of controls, a conclusion made on the basis of enhanced "free" and nonsedimentable phosphatase activities in liver homogenates. The stress factors which previously were included in the group of modifiers of the activity of the endoplasmic reticulum-located enzymes caused some changes in the action of certain chemicals on membranes. Earlier such changes were elicited for carbon tetrachloride and only on low-temperature-conditioned rats for chlorpromazine. The present results show that stress factors studied result in deviations (different in extent and in direction) from the usual effects of chlorpromazine, 2,4-dinitrophenol, phenobarbital and DDT on liver lysosomes and peroxisomes.  相似文献   
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Neonatal treatments can disrupt prepulse inhibition (PPI) of startle response later in life. Alpha2A-adrenergic receptors (alpha2A-ARs) regulate the release of brain neurotransmitters that may influence PPI. The authors examined the effects of short-term reduction in the neonatal brainstem alpha2A-ARs on subsequent development of this receptor system and acoustic startle reflex in rats. Administration of antisense oligodeoxynucleotide complementary to the alpha2A-ARs on Days 2-4 of life reduced receptor expression in the brainstem by Day 5. The treatment increased alpha2-AR numbers in the cortex, hippocampus, and amygdala at 40 days of age, and in cortex and hypothalamus at 90 days of age. Transient increases in hippocampal and amygdalar alpha2-ARs were accompanied by attenuation of acoustic startle response and impairment of PPI.  相似文献   
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Benzene or benzene-dissolved B1-aflatoxin in low doses promotes an increase of the Thy-1+ cell count in the bone marrow of mice and an enhancement of the thymusdependent immune response.In vitro aflatoxin and benzene are unable to induce the expression of Thy-1-antigen in bone marrow T-precursors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N o 2, pp. 158–160, February, 1994 Presented by S. A. Neifakh, Member of the Russian Academy of Medical Sciences  相似文献   
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Brain Research Institute, Russian Academy of Medical Sciences, Moscow. Institute of Biological Research, Belgrade, Yugloslavia. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 7, pp. 56–58, July, 1992.  相似文献   
18.
Two categories of specific binding sites for the β-adrenergic ligand3H-dihydroalprenolol have been revealed on the cells of Ehrlich's ascitic carcinoma. The synthesis of DNA in the tumor cell culture possessed different sensitivities to α- and β-adrenergic preparations. Propranolol, a β-adrenoblocker, suppressed DNA synthesis most intensively in concentrations approaching the therapeutic ones. It is hypothesized that β-adrenoreceptors participate predominantly in the regulation of proliferative processes in Ehrlich's ascitic carcinoma by adrenergic ligands. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, Nno 11, pp. 525–528, November, 1995  相似文献   
19.
The ability for replication of vaccine avian pox viral strains FK and Dessau in cell clones, derived from the EBTr cell line, derived from embryonic bovine trachea, was studied. The derived seven cell clones showed different morphological characteristics and diverse sensitivity to both vaccine avian pox viral strains. Hence, the EBTr-derived cell clones could be used for cultivation, as well as for differentiation of vaccine avian pox viral strains. In addition, studies have been undertaken to elucidate the possible use of cultivated strains in these heterologous cell culture system's vaccine avian pox viral strains for biotechnology, as well as for solving problems, related to infection of people with avian viruses.  相似文献   
20.
This paper reviews the investigations of Prof. L. V. Krushinsky and his colleagues into the genetics of complex behaviors in mammals. The ability of animals to extrapolate the direction of a food stimulus movement was investigated in wild and domesticated foxes (including different fur-color mutants), wild brown rats, and laboratory rats and mice. Wild animals (raised in the laboratory) were shown to be superior to their respective domesticated forms on performance of the extrapolation task, especially in their scores for the first presentation, in which no previous experience could be used. Laboratory rats and mice demonstrated a low level of extrapolation performance. This means that only a few laboratory animals were capable of solving the task, i.e., the percentage of correct solutions was equivalent to chance. The brain weight selection program resulted in two mice strains with a 20% (90-mg) difference in brain weight. Ability to solve the extrapolation task was present in low-brain weight mice in generations 7–11 but declined with further selection. Investigation of extrapolation ability in mice with different chromosomal anomalies demonstrated that animals with Robertsonian translocations Rb(8,17) 1lem and Rb(8,17) 6Sic were capable of solving this task in a statistically significant majority of cases, while mice with fusion of other chromosomes, as well as CBA normal karyotype mice, performed no better than expected by chance. Mice with two types of partial trisomies and animals homo- and heterozygous for translocations were also tested. Although mice with T6 trisomy performed no better than expected by chance, animals with trisomy for a chromosome 17 fragment solved the task successfully. Thus, a genetic component underlying the ability to solve the extrapolation task was demonstrated in three animal species. The extrapolation task in animals is considered to reveal a general capacity for elementary reasoning. The genetic basis of this capacity is very complex.  相似文献   
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