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Mikhalevskaia OB 《Ontogenez》2002,33(4):258-263
Length of elementary shoot is and the number of metamers in them have been compared in a number of ligneous plants. The shoot length varies to greater extent as compared to the number of metamers. The number of metamers with bud scales is the most constant and species-specific. This indicates relative independence of the intrabud stage of the shoot development. 相似文献
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Paulo HG Mansur Lacordaire KP Cury José OB Leite Adriano A Pereira Nilson Penha-Silva Adriano O Andrade 《Biomedical engineering online》2010,9(1):29
Background
The main problem of tremor is the damage caused to the quality of the life of patients, especially those at more advanced ages. There is not a consensus yet about the origins of this disorder, but it can be examined in the correlations between the biological signs of aging and the tremor characteristics. 相似文献5.
Tiago S Hori A Kurt Gamperl Luis OB Afonso Stewart C Johnson Sophie Hubert Jennifer Kimball Sharen Bowman Matthew L Rise 《BMC genomics》2010,11(1):1-22
Background
The Mongolian gerbils are a good model to mimic the Helicobacter pylori -associated pathogenesis of the human stomach. In the current study the gerbil-adapted strain B8 was completely sequenced, annotated and compared to previous genomes, including the 73 supercontigs of the parental strain B128.Results
The complete genome of H. pylori B8 was manually curated gene by gene, to assign as much function as possible. It consists of a circular chromosome of 1,673,997 bp and of a small plasmid of 6,032 bp carrying nine putative genes. The chromosome contains 1,711 coding sequences, 293 of which are strain-specific, coding mainly for hypothetical proteins, and a large plasticity zone containing a putative type-IV-secretion system and coding sequences with unknown function. The cag -pathogenicity island is rearranged such that the cag A-gene is located 13,730 bp downstream of the inverted gene cluster cag B- cag 1. Directly adjacent to the cag A-gene, there are four hypothetical genes and one variable gene with a different codon usage compared to the rest of the H. pylori B8-genome. This indicates that these coding sequences might be acquired via horizontal gene transfer. The genome comparison of strain B8 to its parental strain B128 delivers 425 unique B8-proteins. Due to the fact that strain B128 was not fully sequenced and only automatically annotated, only 12 of these proteins are definitive singletons that might have been acquired during the gerbil-adaptation process of strain B128.Conclusion
Our sequence data and its analysis provide new insight into the high genetic diversity of H. pylori -strains. We have shown that the gerbil-adapted strain B8 has the potential to build, possibly by a high rate of mutation and recombination, a dynamic pool of genetic variants (e.g. fragmented genes and repetitive regions) required for the adaptation-processes. We hypothesize that these variants are essential for the colonization and persistence of strain B8 in the gerbil stomach during inflammation. 相似文献6.
We studied the first cycle of shoot growth of the Quercus robur germlings in which the donor-acceptor relations were changed by removing a part of cotyledons, growing in darkness, or removing growing leaf blades. In all cases, the greatest changes in growth and growth correlations were observed in the shoot upper metameres carrying leaf blades and the least, in lower metameres preformed in the acorn embryo. The removal of growing leaves changed the rhythm of shoot growth. 相似文献
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Mikhalevskaia OB 《Ontogenez》2008,39(2):85-93
Research data on the rhythms of shoot growth in woody plants obtained in the second half of the 20th century are reviewed. Analysis of these data demonstrated different regulation of shoot growth processes at three stages of its development: (1) initiation of shoot primordia, (2) primordia development into phyllome primordia, and (3) visible shoot growth. The growth rhythm after the first stage was realized at the level of apical shoot meristem; at the second stage, at the individual shoot level; and at the third stage, at the whole plant level. 相似文献
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N S Peretokina O S Lin'kova L I Mikhalevskaia V R Katrush M A Kosorukov M A Sinitsyn 《Antibiotiki i khimioterapii͡a》1992,37(7):10-13
Various means for changing the aggregative stability of emulsions in the system of benzylpenicillin fermentation broth filtrate and butyl acetate were tested. It was shown that the use of desemulgators was more efficient than the use of some means for removing the desemulgating admixtures. Moreover, addition of surface active substances after the preliminary thermocoagulation resulted in maximum decreasing of the emulsion aggregative stability. 相似文献
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