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31.
The bilateral intranigral injection of 1-methyl-4-phenyl-pyridinium ion (MPP+) (10 g) produced significant oligokinesia, rigidity and weak tremor in rats. The extrapyramidal disturbances manifest a high-amplitude paroxysmal activity (PA) in the structures studied. It was found that the Pa was remarkable and more stable in the caudata nucleus than in other brain structures. It is PA that gives us the real basis to conclude the formation of the generator of pathologically enhanced excitation (GPEE) in the caudata nuclei. The analysis of PA dynamics revealed that the formation of the GPEE in the caudata nuclei correlated with development of parkinsonian syndrome (PS).  相似文献   
32.
Experiments on mice and rats were made to study the effect of inhibitors-antioxidants (3-hydroxypyridine derivatives) on the central nervous system. It was established that 3-hydroxypyridine derivatives (50 to 200 mg/kg) possess a broad spectrum of psychotropic effects. They cause normalization of behavior in conflict situations, exert an antiaggressive and anticonvulsant action (antagonism with corazol), are capable of potentiating the hypnotic effect of barbiturates, and of suppressing the animals' motor activity if given in high doses. Most compounds under study have antihypoxic and antiamnestic effects.  相似文献   
33.
The capacity of microorganisms from different taxa to adapt to stress conditions with the help of extracellular factors exhibiting similar mechanisms of action was demonstrated. The action of adaptation factors synthesized by the enteric bacterium Escherichia coli, the soil bacterium Bacillus subtilis, and the yeast Candida utilis was characterized in biological tests. It was demonstrated that the factor of accelerated adaptation to new media (FAANM) and the growth-rate-reducing factor (factor X(II)), which decreases the rate of exponential culture growth, were synthesized by all microorganisms tested. Antilysin (factor X(I)), which accelerates cell adaptation to N-ethylmaleimide, was not produced by C. utilis.  相似文献   
34.
Comparative experimental investigation of albino male rats 3 and 16 months old has been performed. 16-month-old rats demonstrated age-dependent functional insufficiency in some behavioural tests. 2 month injection of 3-hydroxypyridine antioxidant (50 mg/kg/day) normalized memory function, motor skill learning and motor coordination function in 16-month-old rats.  相似文献   
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Age-related decrease in blood concentration of testosterone and dehydroepiandrosterone sulfate was found in mining workers living in the European North. The correlation analysis reveals associations of both hormones with biological age and testosterone with plasma lipid profile. The age dependence of cardiovascular risk and the hormonal mechanisms of its development are discussed.  相似文献   
38.
The first study on the frequencies of polymorphic variants of the GSTP1 gene encoding glutathione-S-transferase P1 in Tundra Nenets and Nganasan populations was performed. The subject of the study was the single nucleotide polymorphisms rs1695 (Ile105Val substitution in the protein sequence) and rs1138272 (Ala114Val substitution) that had previously been shown to be associated with cancer and other multifactorial diseases. The data for Tundra Nenets of the Yamalo-Nenets autonomous okrug, Nganasans of the Taimyr Peninsula, and Russian residents of the Northern Siberia were compared. The frequencies of the mutant 105Val and 114Val variants were 10.8% and 0.8% in Nganasans, 23.7% and 4.8% in Nenets, and 35.8% and 9.1% in Russian population samples, respectively. The differences within all pairs of populations were significant for each allele. These differences may characterize the population-level susceptibility to cancer and other multifactorial diseases.  相似文献   
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Background  

Pseudorabies virus (PRV) is an alphaherpesviruses whose native host is pig. PRV infection mainly causes signs of central nervous system disorder in young pigs, and respiratory system diseases in the adult.  相似文献   
40.
A new genus of righteye flounder, Samaretta gen. nov., is described from two specimens (one female and one juvenile) collected in deep waters (470–512 m) from submarine mountains of the southern eastern Pacific. The type species of the new genus, Samaretta perexilis, is characterized by unremarkable (i.e., not elongated) anterior dorsal fin rays, four pectoral fin rays, six parapophyses, reduced lateral line canals, a very slender body, large head and eyes, and minute scales. An updated key to the samarid genera is presented.  相似文献   
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