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11.
Sampling properties of DNA sequence data in phylogenetic analysis 总被引:26,自引:6,他引:20
We inferred phylogenetic trees from individual genes and random samples of
nucleotides from the mitochondrial genomes of 10 vertebrates and compared
the results to those obtained by analyzing the whole genomes. Individual
genes are poor samples in that they infrequently lead to the whole-genome
tree. A large number of nucleotide sites is needed to exactly determine the
whole-genome tree. A relatively small number of sites, however, often
results in a tree close to the whole-genome tree. We found that blocks of
contiguous sites were less likely to lead to the whole-genome tree than
samples composed of sites drawn individually from throughout the genome.
Samples of contiguous sites are not representative of the entire genome, a
condition that violates a basic assumption of the bootstrap method as it is
applied in phylogenetic studies.
相似文献
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V M Tsetlin A I Frolova I V Bessonova E B Zhuk 《Journal of hygiene, epidemiology, microbiology, and immunology》1977,21(3):242-246
Systematic studies of the effectivity of aerosols of the mixtures of DDVP and pyrethroids tested on house flies revealed synergism among the mentioned substances the degree of which was determined by the composition of the mixtures. Among the formulae under study, the mixture of DDVP and neopynamin in a ratio 9 : 1 is of greatest interest. 相似文献
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E S Zalmanzon E I Frolova B Rikhter L N Mikha?lova R L Turetskaia 《Molekuliarnaia biologiia》1979,13(2):292-308
Seven cell lines transformed by adenovirus type 5 and its DNA were obtained. It was shown that different cell lines contain the fragments of viral DNA which differ in length and number of copies per DNA of diploid cells. They contain from the left end 6% of the viral DNA to complete or almost complete viral genome. All studied cell lines were sensitive to reinfection with adenovirus type 5. They produced no virus being cocultivated with cell sensitive to the virus. No cell line was able to induce tumors even in immunosuppressed newborn rats. All cell lines formed colonies in soft agar. The level of virus-specific antigens was higher in cells that contained a large part of the viral genome. The methods used did not allow to correlate the biological properties of the transformed cells with the length and the number of copies of the integrated part of the viral genome. 相似文献
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Frolova A. A. Merkel A. Y. Kuchierskaya A. A. Bonch-Osmolovskaya E. A. Slobodkin A. I. 《Antonie van Leeuwenhoek》2021,114(9):1387-1397
Antonie van Leeuwenhoek - The diversity of anaerobic microorganisms in terrestrial mud volcanoes is largely unexplored. Here we report the isolation of a novel sulfate-reducing alkaliphilic... 相似文献
20.
Water hyacinth Eichhornia crassipes is considered the most damaging aquatic weed in the world. However, few studies have quantified the impact of this weed economically and ecologically, and even fewer studies have quantified the benefits of its control. This paper focuses on water loss saving as the benefit derived from biological control of this plant between 1990 and 2013 at New Year’s Dam, Alicedale, Eastern Cape, South Africa. Estimates of water loss due to evapotranspiration from water hyacinth vary significantly; therefore, the study used three different rates, high, medium and low. A conservative raw agriculture value of R 0.26 per m3 was used to calculate the benefits derived by the water saved. The present benefit and cost values were determined using 10% and 5% discount rates. The benefit/cost ratio at the low evapotranspiration rate was less than one, implying that biological control was not economically viable but, at the higher evapotranspiration rates, the return justified the costs of biological control. However, at the marginal value product of water, the inclusion of the costs of damage to infrastructure, or the adverse effects of water hyacinth on biodiversity, would justify the use of biological control, even at the low transpiration rate. 相似文献