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981.
Kulakov IuK Zheludkov MM Tolmacheva TA Alekseeva NV Kovalev IuN Skavronskaia AG Gintsburg AL Mikhaĭlova IuP Kalmykov VV Shumilov KV 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》2000,(4):7-12
Ten strains isolated from sick dogs in 1998 in St. Petersburg were studied by traditional and molecular biological methods of Brucella identification. PCR study confirmed that the isolated cultures were Brucellae, and comparative study of the traditional phenotypical characteristics and protein and antigenic composition allowed referring all the isolated strains to B. canis. Traditional identification showed similarity of 7 strains with the reference B. canis strain RM6/66, and 3 strains were similar to B. canis Mex 51 strain. These results confirmed the division of B. canis into two biovars. Polyacrylamide gel electrophoresis with sodium dodecyl sulfate demonstrated the identity of protein profiles of 10 strains isolated from dogs to the reference B. canis RM6/66 strain. Immunoblotting analysis with S- and R-specific rabbit antisera also demonstrated the identity of antigens binding IgG antibodies in the strains isolated from dogs to the reference B. canis RM6/66 strain. 相似文献
982.
Bogdanova EA Nesvizhskiĭ IuV Gerasimova EV Zverev VV 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2007,(6):64-68
Effects of substrate phase state and time factor on variability of human fecal microbiota were studied. It was shown that microecological system of native feces was characterized by marked time-dependent variability. It is unstable and begins to destruct after 24 hours of cultivation. The most sensitive elements of the system were bifidobacteria and Escherichia coli. Change of phase state of biotope eliminated the effect of factor limiting the microecosystem development, which allowed species of obligate and transitory microflora to freely colonize the growth substrate and interact with each other. The mentioned facts demonstrate that fecal microbiota exists in the environment of excess of growth substrate, which colonization is limited by cluster structure of biotope of native feces. It was concluded that phase state of growth substrate and duration of cultivation are important factors determining the population variability of fecal microbiota. 相似文献
983.
The profiles of the utilization of 20 protein amino acids in 118 Klebsiella pneumoniae sub- sp. pneumoniae, K. oxytoca, K. planticola, K. mobilis, Enterobacter cloacae, Serratia marscescens, S. liquefaciens, Escherichia coli strains isolated from clinical material were studied. The utilization of amino acids was determined on minimal saline agar containing amino acid as the only source of nitrogen and carbon; the results were evaluated after 72-hour incubation at 37 degrees C. 17 profiles of amino-acid utilization were thus determined, most of them genus-specific in enterobacteria: Klebsiella (profiles No. 1--6, 9, 10), Enterobacter (No. 11--13), Serratia (No. 14--16), Escherichia (No. 17). The full coincidence of amino-acid utilization profiles in bacteria of K. mobilis (No. 1, 6) and K. pneumoniae subsp. pneumoniae with out of such profiles in bacteria of the genera Enterobacter, Serratia, Escherichia was established, which confirmed that K. mobilis (formerly Enterobacter aerogenes) belonged to the genus Klebsiella. 相似文献
984.
Low-amplitude potentials (10-130 microV) related to the action of a distant branch of the climbing fiber, which elicits complex spikes of the reference Purkinje cell were revealed by means of potential averaging synchronously with complex spikes of Purkinje cells in 10 out of 255 paired records of cerebellar Purkinje cells activity and extracellular field potentials at interelectrode distances of 200-1500 microns. These potential waves had a stable form in independent sets of data. In 3 out of 10 cases, the low-amplitude potentials included a slow (about 100 ms in duration) component. In one case, both test and reference electrodes recorded both simple and complex spikes of different Purkinje cells so that complex spikes of both cells were practically synchronous (conditional probability of complex spikes p = 0.97, onset time difference 0.54 ms). Thus for the first time in cerebellar physiology both simple and complex spikes activity of two Purkinje cells controlled by the same climbing fiber was recorded. 相似文献
985.
Tselevych MV Fafula RV Halan MB Sanahurs'kyĭ DI 《Ukrainski? biokhimicheski? zhurnal》2007,79(1):53-57
The functional confirmation of availability of Ca2+ transport initially-active systems in the embryo cells of loach Misgurnus fossilis L. has been obtained. Using thapsigargin, the specific inhibitor of endoplasmic reticulum of Ca2+, Mg(2+)-ATPase, this enzyme activity was divided into thapsigargin-sensitive (actually endoplasmic reticulum Ca2+, Mg(2+)-ATPase) and thapsigargin-insensitive (plasma membrane Ca2+, Mg(2+)-ATPase) constituents. The Ca(2+)-independent Mg(2+)-dependent ATPase activity makes above 39.7% of the common Ca2+, Mg(2+)-ATPase activity of embryo loach. The periodic changes of Ca2+, Mg(2+)-ATPase activity (except for the changes of plasma membrane Ca2+, Mg(2+)-ATPase activity) were found out, which coincide with periodic [Ca2+]i oscillations during the synchronous divisions of loach blastomers embryos. 相似文献
986.
E. V. Grabovskiĭ P. R. Levashov G. M. Oleĭnik C. L. Olson P. V. Sasorov V. P. Smirnov S. I. Tkachenko K. V. Khishchenko 《Plasma Physics Reports》2006,32(9):718-728
Results are presented from studies of the possibility of using a thin metal foil for recyclable vacuum transmission lines with magnetic insulation in a conceptual fusion reactor based on high-voltage high-current electromagnetic generators. Numerical simulations and experiments in the Angara-5-1 facility were carried out to determine both the threshold for the explosion of a foil heated by a current pulse and the parameters of the plasma layer formed at the foil surface. It was found experimentally that an additional plasma current channel forms on the surface of a 120-μm stainless-steel foil at a linear current density of 0.25–0.5 MA/cm, which corresponds to a magnetic field of 0.3–0.6 MG. For the same conditions, one-dimensional computer simulations of the foil heating were performed in an MHD model by using a wide-range semiempirical equation of state for stainless steel. The calculated threshold for plasma generation on the foil surface is compared with the experimental data. The main parameters of the plasma layer are also calculated at linear current densities of 2–10 MA/cm, which far exceed the threshold current density. The plasma layer parameters as functions of the linear current density are determined for the case of an iron foil. 相似文献
987.
The genetic variability at six cloned minisatellite loci was analyzed in
minke whale populations from the North Atlantic, North Pacific, and
Antarctic Oceans. Three loci displayed only a few different alleles in each
of the three populations, with heterozygosity ranging from 0.00 to 0.47,
and three loci revealed many different alleles in at least two fo the three
populations, with heterozygosity ranging up to 0.98. Using small sample
sizes, samples from two adjacent Antarctic Management Areas were not found
to differ significantly in allele frequencies at any of the six loci. The
use of principal coordinate analysis to detect multilocus disequilibria was
explored. No significant evidence was found of intrapopulation
heterogeneity within the pooled Antarctic sample. Pronounced interoceanic
differences were observed at every locus, confirming the existence of
genetic isolation found earlier using more conventional marker systems. The
populations from the three oceans appear to have diverged to such a degree
that the hypervariable loci have had time to evolve independently and
arrive at different evolutionary stages in different populations. The
frequency of undetected "null" alleles is remarkably high in minke whale
populations compared to human populations and is probably a result of the
cloning protocol used. Minisatellite loci are shown to provide a powerful
population genetic tool, supplying levels of resolution appropriate to
different degrees of evolutionary divergence.
相似文献
988.
Mileĭkovskiĭ BY Nozdrachev AD 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》1997,83(5-6):80-93
Reactions of 277 neurones located in the brain pons dorsolateral portion were analised in staying awake and narcotized rats during immobility reflex, induced by the skin constriction on the neck dorsal surface. Got excited: fast adaptive tactile neurons (n = 32), interneurons (n = 42), and cells forming monosynaptic inputs to the parts of medulla oblongata, which inhibit the movements (n = 10). Were inhibited: somatosensory (n = 42), nociceptive (n = 24) and nonidentificated (n = 14) neurons. In some neurons charge characteristics were stable or slightly modified, namely: respiratory neurons (n = 16), cell group, having stable background firing (n = 72) and stimulating antidromically spontaneously silent ponto-medullar neurons (n = 22). 相似文献
989.
990.
Osadchiĭ OE Pokrovskiĭ VM 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》1997,83(3):49-58
In anaesthetised cats, an increase in the vagal burst rate resulted in a paradoxical decrease of vagal bradycardia. This seems to be due to a shift of the vagal stimulus position towards early phase of cardiac cycle. The mechanism of this paradoxical effect depends on the magnitude of vagal chronotropic effect upon the time of vagal stimulus delivery within cardiac cycle. 相似文献