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31.
The results of the AFLP analysis of 16 leek (Allium porrum) accessions and related species of the sections of the genus Allium are presented. Restriction enzymes and primer combinations for the identification of the genotypes of the A. porrum accessions were chosen. As a result, 265 polymorphic AFLP fragments were amplified for 25 analyzed genotypes, and specific spectra of DNA fragments were obtained for each accession. A total of 24 fragments specific for the A. porrum genome was detected, of which only two characterized the genotypes of individual accessions. A wide range of genetic diversity (0.11–0.32) was revealed for the A. porrum varieties and lines used in the analysis. The highest level of similarity in the analyzed set of accessions was found between A. porrum and sand leek (A. scorodoprasum).  相似文献   
32.
Upon a single injection, taurine (50 and 300 mg/kg) and its amide derivative taurepar (50 mg/kg), irrespective of diet and kinds of stress, as a rule, slightly influence the glycemia level in carp. A long-term load of taurine (a total dose of 1250 mg/kg) significantly reduces the glucose concentration in the blood of fishes kept on a carbohydrate diet. Both preparations existentially change the ratio of proteolytic (PA) and amylolitic (AA) activities in all studied fish. As a result, the G/P coefficient increases considerably. It is suggested that the increase in glycosidase activity under taurine injections has an adaptive significance for benthophagous carp, a large part of the diet of which consists of carbohydrate components.  相似文献   
33.
Six plastome microsatellites were examined in 43 accessions of the genus Capsicum. In total, 33 allelic variants were detected. A specific haplotype of chloroplast DNA was identified for eachCapsicum species. Species-specific allelic variants were found for most wild Capsicum species. The highest intraspecific variation was observed for the C. baccatum plastome. Low cpDNA polymorphism was characteristic of C. annuum:the cpSSRs were either monomorphic or dimorphic. The vast majority of C. annuum accessions each had alleles of one type. Another allele type was rare and occurred only in wild accessions. The results testified again to genetic conservation of C. anuum and especially its cultivated forms. The phylogenetic relationships established for the Capsicum species on the basis of plastome analysis were similar to those inferred from the morphological traits, isozyme patterns, and molecular analysis of the nuclear genome.  相似文献   
34.
Effects of dalargin, a synthetic leu-enkephalin analogue and its antagonist naloxone on synaptic transmission in afferent synapses of ray electroreceptors were investigated using an isolated preparation of Lorenzini ampullae from Black sea rays. It was shown that dalargin (10–6–10–10 mole liter) both decreased background activity and evoked activity of an afferent fiber in a dose-dependent manner. Naloxone (10–5 mole/liter) also inhibited afferent impulsation and completely blocked responses of the Lorenzini ampullae to dalargin application. L-glutamate-induced excitatory responses were reduced in the presence of dalargin. It is suggested that the modulatory action of dalargin on glutamatergic synaptic transmission in the Lorenzini ampullae is exerted via specific opiate receptors.Translated from Neirofiziologiya, Vol. 25, No. 1, pp. 18–21, January–February, 1993.  相似文献   
35.
The open-field behaviour of rats selected for high and low active avoidance level was studied. The data obtained showed the correlated response of two selected lines for avoidance ability with the locomotor activity and emotional reactivity in the open-field situation. The line of a low avoidance value had the low activity level and high defecation score in comparison to the alternative one and to progenitory Krushinsky--Molodkina strain. The correspondence of learning ability and emotionality-motivation performance has been discussed.  相似文献   
36.
The side of preference (first turn of head) was recorded in calves in situation of free equal probability two-sides choice, and rate of reconstruction of conditioned reflex to food presented from the left or from the right was determined. Initially the calves preferred the left turn, i.e. manifested motor asymmetry. Preference to the left turn changed depending on the calves age with the period of 22-23 days. The rate of conditioned reflexes reconstruction was higher in calves with the left-side preference. Correlation of the motor asymmetry and rate of conditioned reflex reconstruction in calves of different age changed in analogy with age changes of asymmetry. Probably the observed periodical changes of asymmetry and its correlation with the rate of reconstruction reflect formation of interhemispheric interactions in regulation of the organism functions in animals ontogenesis.  相似文献   
37.
Syringa species: molecular marking of species and cultivars   总被引:1,自引:0,他引:1  
RAPD analysis was carried out with 22 accessions of the genus Syringa, including six species, one interspecific hybrid, and 15 cultivars. In total, 500 polymorphic fragments were detected; species-specific and cultivar-specific markers were identified. For the first time, genetic polymorphism and genome similarity coefficients were estimated and phylogenetic relationships were established for the genus Syringa.  相似文献   
38.
39.
The effect of the hormone-like estrogen-progestagen preparation megestranol and of megestranol-spasmolytin combination on the activity of metabolic processes in the uterine mucous membrane was studied in experiments on rats. Results of cytochemical studies showed megestranol and megestranol-spasmolytin combination to change the metabolic activity of the uterine mucous membrane resulting in a decrease in the RNA content in the epithelial cells of the endometrial glands, thereby creating conditions preventing normal implantation and development of the fertilized ovum.  相似文献   
40.
Molecular analysis of the genome was performed for 14 species of the genus Stachys. RAPD and ISSR analyses of the Stachys genome revealed 574 polymorphic fragments, including genus- and species-specific markers. Based on the patterns, UPGMA and the Jacquard coefficient were used to estimate the genetic distances between Stachys species and populations and to construct dendrograms reflecting the phylogenetic relationships among the Stachys species. Molecular analysis of the Stachys genome refined the phylogenetic positions of some species and revealed synonymous species.  相似文献   
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