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991.
I. Boubriak T. Akimkina V. Polischuk A. Dmitriev S. McCready D. Grodzinsky 《Cytology and Genetics》2016,50(6):381-399
Thirty years after the Chernobyl explosion we still lack information regarding the genetic effects of radionuclide contamination on the plant population. For example, are plants adapting to the low dose of chronic ionising irradiation and showing improved resistance to radiation damage? Are they coping with changing/increased pathogenicity of fungi and viruses in the Chernobyl exclusion (ChE) zone? Are plant populations rapidly accumulating mutational load and should we expect rapid micro-evolutionary changes in plants in the Chernobyl area? This review will try to summarise the current knowledge on these aspects of plant genetics and ecology and draw conclusions on the importance of further studies in the area around Chernobyl. 相似文献
992.
Dry Heat Inactivation of Bacillus subtilis var. niger Spores as a Function of Relative Humidity 总被引:2,自引:2,他引:0
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Dry heat sterilization of Bacillus subtilis var. niger spores at 105 C is enhanced in the relative humidity range 0.03 to 0.2%. D-values of 115 and 125 C are predicted by a kinetic model with parameters set from 105 C data. These predictions are compared to observations. 相似文献
993.
The differentiation of spermatids in the marmoset (Callithrix jacchus, n = 9) testis is described here at the light-microscopic level employing serial semithin sections. The definition of 8 different phases of spermiogenesis, i.e. the formation of spermatids, is based upon the changes in the development of nucleus, acrosome and flagellum. 相似文献
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New methods of analysing genetic data provide powerful tools for quantifying dispersal patterns and reconstructing population
histories. Here we examine the population structure of the bumblebee Bombus hortorum in a model island system, the Western Isles of Scotland, using microsatellite markers. Following declines in other species,
B. hortorum is the only remaining long-tongued bumblebee species found in much of Europe, and thus it is of particular ecological importance.
Our data suggest that populations of B. hortorum in western Scotland exist as distinct genetic clusters occupying groups of nearby islands. Population structuring was higher
than for other bumblebee species which have previously been studied in this same island group (Fst = 0.16). Populations showed significant isolation by distance. This relationship was greatly improved by using circuit theory
to allow dispersal rates to differ over different landscape features; as we would predict, sea appears to provide far higher
resistance to dispersal than land. Incorporating bathymetry data improved the fit of the model further; populations separated
by shallow seas are more genetically similar than those separated by deeper seas. We argue that this probably reflects events
following the last ice age when the islands were first colonized by this bee species (8,500–5,000 ybp), when the sea levels
were lower and islands separated by shallow channels would have been joined. In the absence of significant gene flow these
genetic clusters appear to have since diverged over the following 5,000 years and arguably may now represent locally adapted
races, some occurring on single islands. 相似文献
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999.
R D Gavriliaka N A Semina L I Fiks S V Shabalina N V Tsvetkova 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1985,(1):45-48
ELISA is used for detecting the soluble staphylococcal antigen in patients with purulent septic infections. The optimum conditions for the assay have been established: the dose of staphylococcal gamma globulin for plate sensitization should be 5.0-10.0 micrograms/ml, the pH of the buffer solution 9.6-10.0, the time and temperature of incubation 18-20 hours at 4 degrees C or 5 hours at 37 degrees C. The possibility of using plates manufactured in the USSR has been shown. The sensitivity of the above diagnostic test system is 0.005 microgram/ml. 相似文献
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