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New hydrophilic polymer sorbents comprising reactionary sites which are complementary to a molecule of antibiotic erythromycin were synthesized by the method of molecular imprinting. A series of similar sorbents without reactionary sites was used for comparison of sorption characteristics. Sorption of erythromycin on both types of polymer sorbents synthesized was studied in a wide range of pH and ionic strength. Selectivity of erythromycin sorption on molecularly imprinted cross-linked polymers was shown to depend on the specific interaction of target molecule with polymer matrix. This type of sorbent is perspective for the development of antibiotic purification directly from a culture medium Saccharopolyspora erythreus.  相似文献   
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In 2016, an outbreak of anthrax killing thousands of reindeer and affecting dozens of humans occurred on the Yamal peninsula, Northwest Siberia, after 70 years of epidemiological situation without outbreaks. The trigger of the outbreak has been ascribed to the activation of spores due to permafrost thaw that was accelerated during the summer heat wave. The focus of our study is on the dynamics of local environmental factors in connection with the observed anthrax revival. We show that permafrost was thawing rapidly for already 6 years before the outbreak. During 2011–2016, relatively warm years were followed by cold years with a thick snow cover, preventing freezing of the soil. Furthermore, the spread of anthrax was likely intensified by an extremely dry summer of 2016. Concurrent with the long-term decreasing trend in the regional annual precipitation, the rainfall in July 2016 was less than 10% of its 30-year mean value. We conclude that epidemiological situation of anthrax in the previously contaminated Arctic regions requires monitoring of climatic factors such as warming and precipitation extremes.

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The role of the gene ER2 in plant development has been studied by the analysis of the erecta2 (er2) mutant of Arabidopsis thaliana (L.) Heynh. It was shown that the mutation er2 provides pleiotropic effect on the development of all aboveground organs. It induces shortening and thickening of the stem, leaves and all flower organs, though it does not change the sensitivity to gibberellin. Changes in the morphology of the shoot organs are due to the changes in cell polarity. The cells get wider and shorter compared to the wild type. It was found that the gene ER2 is located in the lower arm of the chromosome 1. It complementarily interacts with the gene ER that plays an important role in the control of intercellular interactions.  相似文献   
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Peculiarities of geographical distribution and distribution among hosts of the haemosporidian parasites, which cause lethal diseases in poultry, are specified. So far, 11 species of such parasites have been described. This represents about 5% of bird haemosporidian parasites. The haemosporidians cause the lethal epizooties in turkeys, chickens, ducks, geese, pigeons and domesticated ostriches. One species of parasites belongs to the family Haemoproteidae, six--to Plasmodiidae, and four--to Leucocytozoidae. The agents of lethal haemosporidioses have been recorded in domestic birds of the orders Galliformes, Anseriformes, Columbiformes and Struthiorniformes. The majority of these parasites (eight species of 73%) occurs in the galliform birds. Each other order obtaines only one species of parasites. Five species parasitize turkey, which is the main host of the agent of lethal haemosporidioses. The majority of highly virulent haemosporidian species have been recorded throughout a global territory, which includes the Holarctic, Ethiopian and Oriental zoogeorgaphical regions. Three species of these parasites have been found in the Neotropical region, while none species has been recorded in Australia. The majority of highly virulent haemosporidian species have quite clear outlined areas, that is important to know for the prophilactic purposes including the quarantine of bird introducing from endemic territories.  相似文献   
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We have studied the activity of the chimeric gene DR5::GUS that indicates the spatial pattern of free auxin distribution and relative auxin level in the tissues of A. thaliana plants. It is established that the temperature sensitive abruptus mutation leads to temperature dependent increased accumulation of the free auxin in leaves, staments, and sepals in comparison to control plants homozygous for the wild type allele ABRUPTUS/PINOID. Our data revealed the important role of the ABRUPTUS/PINOID gene in the regulation of the auxin polar transport.  相似文献   
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Ledbedeva OV  Ezhova TA  Melzer S 《Genetika》2005,41(8):1068-1074
Mutant Arabidopsis thaliana taeniata (tae) plants are characterized by an altered morphology of leaves and the inflorescence. At the beginning of flowering, the inflorescence produces fertile flowers morphologically intermediate between a shoot and a flower. The recessive mutation tae also causes the formation of ectopic meristems and shoot rosettes on leaves. The expressivity of the mutant characters depend on the temperature and photoperiod. Analysis of the activity of KNOX class I genes in the leaves of the tae mutant has demonstrated the expression of genes KNAT2 and STM and an increase in the expression of genes KNAT1 and KNAT6 compared to wild-type leaves. These data indicate that the TAE gene negatively regulates the KNAT1, KNAT2, KNAT6, and STM genes.  相似文献   
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