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11.
S P Romanov 《Neirofiziologiia》1989,21(3):379-389
The electron analogue of a neuron working in real time scale is suggested. The sequence of signals' transformation in this analogue is in line with synaptic, postsynaptic membrane and somatic processes. Data on the synapse as on a "key" and on the postsynaptic membrane as on the ion channel with conductivity changed under the influence of a mediator and intracellular potential permit making the neuron analog on the basis of the pulse generator with the possibility to reproduce the synaptic apparatus activity and the neuronal dendrites' structure. The processes of the impulse flow transformation characteristic for neurons of different types, for example motoneurons and Renshow cells are modelled by changing the parameters of the membrane resistance and capacity. The study of simple networks has shown possible to use the suggested analogues for investigating principles of neuronal structure organizations and mechanisms of neuronal interactions, particularly in the motor control system. 相似文献
12.
Michael?N.?Romanov Laura?M.?Daniels Jerry?B.?Dodgson Mary?E.?DelanyEmail author 《Chromosome research》2005,13(2):215-222
The chicken genome, like those of most avian species, contains numerous microchromosomes that cannot be distinguished by size
alone. Unique properties attributed to the microchromosomes include high GC content and gene density, and an enhanced recombination
rate. Previously, microchromosome GGA 17 was shown to align with the consensus genetic linkage group E41W17, and bacterial
artificial chromosome (BAC) clones containing E41W17 markers were isolated and assigned on the physical BAC map as well as
the recently assembled draft chicken genome sequence. For this study, these same BACS were utilized as probes for fluorescence
in-situ hybridization (FISH) to develop the GGA 17 cytogenetic map. Here we detail the chromosome order of ten BAC DNAs, thereby
deriving a cytogenetic map of GGA 17 that is simultaneously integrated with both the linkage map and genome sequence. The
location of the FISH probes together with the morphological appearance of the chromosome suggested that GGA 17 is an acrocentric
chromosome whose cytogenetic map orientation is reversed from that currently indicated by the linkage map and draft genome
sequence. The reversed orientation and the centromere location of GGA 17 were confirmed experimentally by dual-colour FISH
hybridization using terminal BACs and the centromere-specific CNM oligonucleotide as probes. An advantage of this cyto-genomic
approach is the improved alignment of the sequence and linkage maps with cytogenetic features such as the centromere, telomeres,
p and q arms, and staining patterns indicating GC versus AT content. 相似文献
13.
14.
Tkacheva NV Romanov YA Sentyurova LG Belopasov VV 《Bulletin of experimental biology and medicine》2002,133(6):538-539
The structure of vascular plexuses of brain ventricles in newborns developed under hypoxic conditions does not correspond to gestational age. Chronic hypoxia decreases activity of succinate dehydrogenase and iron content in vascular plexuses of brain ventricles. 相似文献
15.
V. I. Romanov 《Bulletin of experimental biology and medicine》1966,61(5):593-595
Summary It was shown that in mice of strains C3H and C57B1 acidophilic cells predominate in the hypophysis. Basophilic cells are least in number. These are followed by chromophobic cells. Variations in the quantitative composition of cells according to the cycle stages occur among the basophilic cells of the peripheral zone of the hypophysis. The largest content of basophils was noted in the diestrus, the smallest of the estrus (in mice of strain C3H) and metestrus (in mice of strain C57B1).Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 61, No. 5, pp. 116–118, May, 1966 相似文献
16.
D. S. Gembitskii A. I. Antokhin N. Ya. Popova Yu. A. Romanov 《Bulletin of experimental biology and medicine》1995,120(5):1147-1150
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
17.
Lavigne R Burkal'tseva MV Robben J Sykilinda NN Kurochkina LP Grymonprez B Jonckx B Krylov VN Mesyanzhinov VV Volckaert G 《Virology》2003,312(1):49-59
The complete DNA sequence of a new lytic T7-like bacteriophage phiKMV is presented. It is the first genome sequence of a member of the Podoviridae that infects Pseudomonas aeruginosa. The linear G + C-rich (62.3%) double-stranded DNA genome of 42,519 bp has direct terminal repeats of 414 bp and contains 48 open reading frames that are all transcribed from the same strand. Despite absence of homology at the DNA level, 11 of the 48 phiKMV-encoded putative proteins show sequence similarity to known T7-type phage proteins. Eighteen open reading frame products have been assigned, including an RNA polymerase, proteins involved in DNA replication, as well as structural, phage maturation, and lysis proteins. Surprisingly, the major capsid protein completely lacks sequence homology to any known protein. Also, the strong virulence toward many clinical P. aeruginosa isolates and a short replication time make phiKMV attractive for phage therapy or a potential source for antimicrobial proteins. 相似文献
18.
Yu. A. Romanov T. N. Ivchenko Z. F. Sultanova 《Bulletin of experimental biology and medicine》1988,105(3):408-411
Department of Biology, Medico-Biological Faculty, N. I. Pirogov Second Moscow Medical Institute. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 105, No. 3, pp. 345–347, March, 1988. 相似文献
19.
Vladimir Turzhitsky Yang Liu Nahla Hasabou Michael Goldberg Hemant K. Roy Vadim Backman Randall Brand 《Disease markers》2008,25(6):313-321
Pancreatic cancer screening has been hampered by the high rate of complications associated with interrogating the pancreas. The closest non-invasively accessible mucosa available for pancreatic cancer screening is the periampullary duodenal tissue. Our earlier report has shown the potential of using optical markers to interrogate this tissue for the presence of pancreatic cancer. In this study, we report a larger data set of low-coherence enhanced backscattering (LEBS) and elastic light scattering fingerprinting (ELF) optical markers from the periampullary duodenal mucosa. Optical measurements from biopsy samples were acquired from a total of 203 patients with varying clinical classification including healthy controls, a family history of pancreatic cancer, pancreatitis, mucinous cystic precursor lesions, pancreatic cancer, and other pancreatic malignancies. Evaluation of the performance of an independent testing set for discriminating healthy control patients from pancreatic cancer patients showed a 95% sensitivity, 71% specificity, and 85% area under the receiver operator characteristic (AUROC) curve. Importantly, this performance was uncompromised for detecting potentially curable stages of the disease. Additionally, optical markers in higher risk populations such as family history and pancreatitis had values between those of healthy control and pancreatic cancer patients, thus allowing for future investigations of screening from these high risk groups. 相似文献
20.
Squires K Lazzarin A Gatell JM Powderly WG Pokrovskiy V Delfraissy JF Jemsek J Rivero A Rozenbaum W Schrader S Sension M Vibhagool A Thiry A Giordano M 《Journal of acquired immune deficiency syndromes (1999)》2004,36(5):1011-1019
BACKGROUND: Atazanavir, an azapeptide protease inhibitor (PI), has pharmacokinetics that allow once-daily dosing, and it is not associated with significant PI-associated dyslipidemia. METHODS: A randomized, double-blind, double-dummy, active-controlled, 2-arm study comparing the antiviral efficacy and safety of atazanavir 400 mg administered once daily with efavirenz 600 mg administered once daily in combination with open-label fixed-dose zidovudine plus lamivudine twice daily. The 810 treatment-naive patients were stratified by HIV RNA level. The primary efficacy end point was the proportion of treated patients with HIV RNA levels <400 copies/mL through week 48. RESULTS: At week 48, HIV RNA levels were <400 copies/mL in 70% of patients receiving atazanavir and 64% of patients receiving efavirenz (intent-to-treat, difference; 95% confidence interval: 5.2%; -1.2%, 11.7%). Median CD4 cell counts increased at comparable magnitudes and rates in the 2 treatment arms (mean change at week 48: 176 cells/mm with atazanavir, 160 cells/mm with efavirenz). Atazanavir-treated patients relative to comparator-treated patients did not demonstrate significant increases in total cholesterol, fasting low-density lipoprotein cholesterol, or fasting triglycerides over 48 weeks of therapy. Atazanavir-linked bilirubin elevations infrequently resulted in treatment discontinuation (<1%). Atazanavir treatment did not increase fasting glucose or insulin levels. CONCLUSIONS: For initial HIV treatment, a highly active antiretroviral therapy regimen of atazanavir/zidovudine/lamivudine is as efficacious and well tolerated as the combination of efavirenz/zidovudine/lamivudine. 相似文献