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1.
V K Khugaeva E D Klimenko P N Aleksandrov G F Leskova M I Reutov 《Biulleten' eksperimental'no? biologii i meditsiny》1985,100(7):15-19
Experiments were made on rabbit fed an atherogenic diet (0.5 g/kg cholesterol) singly for 15 and 24 h and repeatedly for 3, 9 and 30 days. At early stages of lipid metabolism distress the interrelationship was established between blood rheological disorders and microcirculatory abnormalities. The dependence of the initial reaction of some rheological characteristics on their initial level was marked. 相似文献
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We have used an algorithm from the pattern recognition theory "generalized portrait" to find a distinguishing vector for Escherichia coli promoters. We have made an attempt to solve closely linked problems for choosing significant signs of that signal, multiple alignment and for calculation of the recognition vector (matrix). The promoters with known strength have been ranged with this vector. The analysis of the occurrence of predicted promoters has been carried out. The promoters search program for IBM-compatible computers is available from the authors. 相似文献
4.
Iu I Aleksandrov Iu V Grinchenko 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1989,39(5):914-923
The activity of neurones of the anterolateral part of the motor cortex in food-acquisition behaviour was compared in two control rabbits and in three rabbits after the operation of bilateral ablation of the striatal cortex. In two of three operated rabbits the pattern of behavioural specialization lost considerably the specificity peculiar to the motor cortex (predominance of G-neurones activated in grasping of food), approaching (but not becoming identical) the pattern of specialization of the visual cortex neurones: the number of G-neurones decreased in a half, and the number of L-neurones (activated in connection with the acts of instrumental food-acquisition behaviour which animals were trained to in the experimental cage) was doubled. Changes of the activity were significantly less expressed in the third operated rabbit. The number of the neurones activated in food-acquisition behaviour in operated rabbits in comparison with the control ones was reduced in the upper layers of the cortex and increased in the lower layers. The resemblance is discussed of the basic processes of animals learning and behaviour recovery. 相似文献
5.
Payant V; Abukashawa S; Sasseville M; Benkel BF; Hickey DA; David J 《Molecular biology and evolution》1988,5(5):560-567
Nuclear DNA was extracted from each of the eight species comprising the
Drosophila melanogaster species subgroup. Southern hybridization of this
DNA by using a molecular probe specific for the alpha-amylase coding region
showed that the duplicated structure of the amylase locus, first found in
D. melanogaster, is conserved among all species of the melanogaster
subgroup. Evidence is also presented for the concerted evolution of the
duplicated genes within each species. In addition, it is shown that the
glucose repression of amylase gene expression, which has been extensively
studied in D. melanogaster, is not confined to this species but occurs in
all eight members of the species subgroup. Thus, both the duplicated gene
structure and the glucose repression of Drosophila amylase gene activity
are stable over extended periods of evolutionary time.
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S G Vorsanova Iu B Iurov I A Aleksandrov I A Demidova S P Mitkevich 《T?Sitologii?a i genetika》1986,20(4):291-294
The patient with atypical clinic picture of 18p- syndrome is described. The in situ hybridization technique was used to localize chromosome 18-specific cloned sequence to metaphase chromosomes of the proband. The predominant hybridization was found in pericentromeric regions of homologous chromosome 18. The amount of pericentromeric DNA measured by in situ hybridization was different in homologous chromosomes and the number of radioactive grains was statistically greater in the normal chromosome 18 than in the chromosome 18p-. The cause of asymmetrical hybridization of probes to homologous chromosomes 18 is discussed. The results obtained indicate that this probe may be useful in clinical cytogenetics for identification of chromosome 19 in metaphase and interphase cells, determination of breakpoints or studies of pericentromeric DNA polymorphisms. 相似文献
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Unit activity was studied in the posterior sigmoid and proreal gyri of the cat cortex in response to photic, acoustic, and somatic stimulation. The animals were first anesthetized with pentobarbital and, after recovery, were given intravenous injections of bemegride (β-ethyl-β-methylglutarimide) and immobilized with diplacin [1, 3-di(β-platyneciniumethoxy)-benzene hydrochloride]. The state of the preparation used was similar to the state of waking animals as regards the characteristics of its unit activity. Unit responses of the proreal gyrus were chiefly modally nonspecific and consisted of brief suppression of spontaneous activity for 100–200 msec. Neurons of the posterior sigmoid gyrus were characterized by much greater modal specificity and variety of types of responses to stimuli of different modalities. Comparison of the characteristics of unit activity in these parts of the neocortex suggests that the frontal cortex in cats is still a highly unspecialized structure. 相似文献