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1.
Immunological analysis of the antigenic structure of hemagglutinin of newly isolated variants of influenza (H3N2) virus carried out using monoclonal and monospecific antibodies to individual antigenic sites of hemagglutinin showed the 1989-1990 isolates to be markedly different in their antigenic properties from the variants isolated in previous years. Sites with new antigenic properties were determined in hemagglutinin of the isolates. Wide variability was found in the region of three immunodominant sites. The fact of circulation in the human population of influenza viruses of one subtype with different antigenic structures within the limits of one epidemic season was established. 相似文献
2.
Alexander S. Graphodatsky Polina L. Perelman Natalya V. Sokolovskaya Violetta R. Beklemisheva Natalya A. Serdukova Gauthier Dobigny Stephen J. O’Brien Malcolm A. Ferguson-Smith Fengtang Yang 《Chromosome research》2008,16(1):129-143
Canid species (dogs and foxes) have highly rearranged karyotypes and thus represent a challenge for conventional comparative
cytogenetic studies. Among them, the domestic dog is one of the best-mapped species in mammals, constituting an ideal reference
genome for comparative genomic study. Here we report the results of genome-wide comparative mapping of dog chromosome-specific
probes onto chromosomes of the dhole, fennec fox, and gray fox, as well as the mapping of red fox chromosome-specific probes
onto chromosomes of the corsac fox. We also present an integrated comparative chromosome map between the species studied here
and all canids studied previously. The integrated map demonstrates an extensive conservation of whole chromosome arms across
different canid species. In addition, we have generated a comprehensive genome phylogeny for the Canidae on the basis of the
chromosome rearrangements revealed by comparative painting. This genome phylogeny has provided new insights into the karyotypic
relationships among the canids. Our results, together with published data, allow the formulation of a likely Canidae ancestral
karyotype (CAK, 2n = 82), and reveal that at least 6–24 chromosomal fission/fusion events are needed to convert the CAK karyotype
to that of the modern canids.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
Svetlana A. Romanenko Natalia A. Sitnikova Natalya A. Serdukova Polina L. Perelman Nadezhda V. Rubtsova Irina Yu. Bakloushinskaya Elena A. Lyapunova Walter Just Malcolm A. Ferguson-Smith Fengtang Yang Alexander S. Graphodatsky 《Chromosome research》2007,15(7):891-897
Using cross-species chromosome painting, we have carried out a comprehensive comparison of the karyotypes of two Ellobius species with unusual sex determination systems: the Transcaucasian mole vole, Ellobius lutescens (2n = 17, X in both sexes), and the northern mole vole, Ellobius talpinus (2n = 54, XX in both sexes). Both Ellobius species have highly rearranged karyotypes. The chromosomal paints from the field vole (Microtus agrestis) detected, in total, 34 and 32 homologous autosomal regions in E. lutescens and E. talpinus karyotypes, respectively. No difference in hybridization pattern of the X paint (as well as Y paint) probes on male and female
chromosomes was discovered. The set of golden hamster (Mesocricetus auratus) chromosomal painting probes revealed 44 and 43 homologous autosomal regions in E. lutescens and E. talpinus karyotypes, respectively. A comparative chromosome map was established based on the results of cross-species chromosome painting
and a hypothetical ancestral Ellobius karyotype was reconstructed. A considerable number of rearrangements were detected; 31 and 7 fusion/fission rearrangements
differentiated the karyotypes of E. lutescens and E. talpinus from the ancestral Ellobius karyotype. It seems that inversions have played a minor role in the genome evolution of these Ellobius species. 相似文献
4.
Fibrinogen adsorption by PS latex particles coated with various amounts of a PEO/PPO/PEO triblock copolymer 总被引:1,自引:0,他引:1
Bohner M Ring TA Rapoport N Caldwell KD 《Journal of biomaterials science. Polymer edition》2002,13(6):733-746
Polystyrene (PS) latex particles of different sizes were adsorption coated with the polymeric surfactant Pluronic F108 (PEO129-PPO56-PEO129). The commercial surfactant was found to have a bimodal molecular weight distribution. However, the maximum surface concentrations resulting from adsorption of either the purified high molecular weight component or the composite were identical. An increase in the copolymer surface concentration on 252-nm particles was found to decrease their fibrinogen uptake exponentially. At maximum copolymer surface concentration, the fibrinogen uptake was two orders of magnitude lower than that of bare particles (down from 3.3 mg/m2 to 0.03 mg/m2). This surface protection was equally effective whether the adsorption involved the bimodal polymer surfactant or the purified high molecular weight fraction. The PEO tail mobility was investigated with electron paramagnetic resonance (EPR), and found to increase with an increase in polymer surface concentration. The comparatively slow motion of the PEO chains at low surface concentration indicated that not only the PPO block, but also the PEO blocks interacted hydrophobically with the PS surface. When the copolymer surface concentration was increased, the PEO tails were gradually being released, acquiring higher mobility as the surface became covered by the more strongly binding PPO blocks. Results obtained with F108 coated particles of different sizes showed that particle size had a significant effect on the fibrinogen uptake, with larger particles showing larger fibrinogen uptakes. 相似文献
5.
6.
Kolomeets Natalya S. Uranova Natalya A. 《European archives of psychiatry and clinical neuroscience》2022,272(6):947-955
European Archives of Psychiatry and Clinical Neuroscience - Neuroimaging, genetic and molecular biological studies have shown impaired intra-cortical myelination in patients with schizophrenia,... 相似文献
7.
8.
Soukharev S Hammond D Ananyeva NM Anderson JA Hauser CA Pipe S Saenko EL 《Blood cells, molecules & diseases》2002,28(2):234-248
Deficiency in a coagulation factor VIII (FVIII) causes a genetic disorder hemophilia A, which is treated by repeated infusions of expensive FVIII products. Recombinant FVIII (rFVIII), the culmination of years of extensive international research, is an important alternative to plasma-derived FVIII (pdFVIII) and is considered to have a higher margin of safety. Advances in biotechnology allowed production of rFVIII at industrial scale, which significantly improved treatment of hemophilia A patients. We review the contemporary methods used for FVIII expression in mammalian cell culture systems and discuss the factors responsible for insufficient recoveries of rFVIII, such as inefficient accumulation of FVIII mRNA in the cell, complexity of the mechanisms of FVIII secretion, and instability of secreted FVIII. The approaches to improve the yield of rFVIII in cell culture systems include genetic engineering of B-domain-deleted FVIII, introduction of introns into FVIII cDNA constructs for more efficient processing and accumulation of FVIII mRNA, and introduction of mutations into chaperone-binding sites of FVIII to improve its secretion. Design of FVIII with prolonged half-life in vivo is considered as another promising direction in improving rFVIII protein and efficiency of hemophilia A therapy. As an alternative to expression of rFVIII in cell culture systems, we discuss production of rFVIII in transgenic animals, where high levels of rFVIII have been successfully secreted into milk. We also pay attention to the major limitations of this approach, such as safety issues associated with potential transmission of animal pathogens. Finally, we present a brief characterization of commercial recombinant FVIII products currently available on the market for hemophilia A treatment. 相似文献
9.
On the issue of choosing psychodiagnostic methods of measuring and scoring of cognitive deficit in case of schizophrenia 下载免费PDF全文