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81.
Further studies on the role of cell-wall-degrading enzymes in cell-wall loosening in oat coleoptiles
A fungal endo-ß-l,3-glucanase was compared with afungal exo-ß-1,3-glucanase with respect to their effectson elongation and cell-wall extensibility in oat coleoptilesegments. The exo-enzyme enhanced elongation and extensibilityof the cell wall. Its effect was not additive to the effectof indole-3-acetic acid when given together with the latter,at least during 3 hr of incubation. Endo-glucanase showed nosignificant effect on elongation and no interaction with theexo-enzyme. Auxin and exo-glucanase increased extensibilityof the cell wall. The exo-glucanase was separated by isoelectricfocusing. The two fractions which were separated and showedglucanase activity induced elongation and cell wall loosening. (Received March 16, 1970; ) 相似文献
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Ya. N. Shoikhet V. I. Kiselev E. V. Zaitsev I. B. Kolyado B. Yu. Konovalov S. Bauer B. Grosche W. Burkart 《Radiation and environmental biophysics》1999,38(3):207-210
A registry of the rural population in the Altai region exposed to fallout from nuclear tests at the Semipalatinsk test site
(STS) was established more than four decades after the first Soviet nuclear explosion on August 29, 1949. Information about
individuals living in an exposed and a control area was collected using all available local sources, such as kolkhoz documentation, school registries, medical treatment records and interviews with residents. As a result, a database comprising
an exposed group of 39 179 individuals from 53 Altai region villages, 6769 external and 3303 internal controls was compiled.
For several settlements, effective dose estimates reached the level of 1.5 Sv, while the average effective dose estimate in
the exposed group was 340 mSv. Dosimetric data, vital status information and health records gathered at rayon and village
medical facilities are held in the registry. Cause-of-death information for deceased residents is obtained from death registration
forms archived at the Altai region vital statistics office. At present, a follow-up of approximately 40% of the population
exposed in 1949 has been done. More will be added by searching for migrants to the larger towns of the Altai region, i.e.
Barnaul, Rubtsovsk and Biisk. In order to assess the influence of radiation exposure, analytical studies with a case-control
design for stomach and lung cancer are currently being prepared. The number of known cases is sufficient to detect an odds
ratio of 1.5 at the 95% confidence level. Epidemiological studies in populations affected by fallout from STS may be equally
important to the atomic bomb survivors’ study for the direct quantification of radiation effects. The range of exposure rates
experienced will extend the acute high-dose-rate findings from Hiroshima/Nagasaki towards acute and protracted lower exposures,
which are more relevant for radiation protection issues.
Received: 3 March 1999 / Accepted in revised form: 8 June 1999 相似文献
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Meshcheryakova Yu. A. Eldarov M. A. Migunov A. I. Stepanova L. A. Repko I. A. Kiselev C. I. Lomonossoff G. P. Skryabin K. G. 《Molecular Biology》2009,43(4):685-694
The epitope presentation system for the ectodomain of the M2 protein (M2e) of the influenza A virus was constructed on the
basis of the cowpea mosaic virus (CPMV) for expression in the plant Vigna unguiculata. CPMV is widely used as a vector to produce immunogenic chimeric virus particles (CVPs) bearing epitopes of various infectious
human and animal pathogens. To produce chimeric CPMV particles in plants, two binary vectors were constructed to bear a modified
gene coding for the CPMV S-coat protein with insertions of M2e epitopes of human influenza and bird influenza viruses. Antigenic
and immunogenic properties of CVPs were investigated in mice immunization experiments. CVPs were shown to induce anti-M2e
IgG production and to partly protect mice against a challenge with low doses of the influenza virus. However, low infectivity
and immunogenicity of chimeric CPMV particles indicate that the plant virus-based systems for M2e epitope presentation requires
further optimization in order to use plants as a possible source of flu vaccines. 相似文献
87.
Quaternary and Late Tertiary fossil insects from different regions of Eurasia are studied. The main areas are northeastern
Eurasia (Part 1) and Belarus and adjacent regions (Part 2). Paleoenvironmental and climatic reconstructions for these regions
are provided and compared with other parts of Europe, Asia, and North America. Hundreds of fossil insect localities are described;
thousands of insect sclerites are recognized. 相似文献
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Kiselev KV 《Applied microbiology and biotechnology》2011,90(2):417-425
The polyphenol trans-resveratrol (3,5,4′-trihydroxy-trans-stilbene) is one of the best known plant secondary metabolites. The number of articles
devoted to trans-resveratrol has been steadily increasing. Trans-resveratrol is a molecule that is beneficial to human health; this explains the high level of interest in trans-resveratrol among different research groups. Therefore, it is important to develop an effective method to produce this compound
commercially. The applicability of biotechnology for trans-resveratrol extraction is still uncertain. This review describes and compares the available biotechnological methods of trans-resveratrol production, focusing on their advantages and disadvantages. 相似文献
90.