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1.
J J Hauw J M Boutry A M Guillermin M P Barbe H Boissonnet 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1986,302(14):543-548
20 day-old rat thoracic dorsal root ganglia were grown for 48 hrs. in Iscove's medium supplemented with 8% fetal calf serum and 600 mg/100 ml glucose. Naftidrofuryl was added at 10(-6), 10(-7), 10(-8) and 10(-9) M concentrations to the culture medium. The 10(-7) and 10(-8) M concentrations induced a statistically significant increase of the number (30 to 40%; p = .0054 and .0016, respectively) and length (20 to 30%; p = .0012 and .001, respectively) of neurites of the outgrowth measured after Bodian's protargol impregnation. The width of the cell spread in the outgrowth was also enlarged at the 10(-7) and 10(-8) M concentrations (18 to 26%; p = .0012; p less than .0001, respectively). 相似文献
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The phylogeny of Greya Busck (Lepidoptera: Prodoxidae) was inferred from
nucleotide sequence variation across a 765-bp region in the cytochrome
oxidase I and II genes of the mitochondrial genome. Most parsimonious
relationships of 25 haplotypes from 16 Greya species and two outgroup
genera (Tetragma and Prodoxus) showed substantial congruence with the
species relationships indicated by morphological variation. Differences
between mitochondrial and morphological trees were found primarily in the
positions of two species, G. variabilis and G. pectinifera, and in the
branching order of the three major species groups in the genus. Conflicts
between the data sets were examined by comparing levels of homoplasy in
characters supporting alternative hypotheses. The phylogeny of Greya
species suggests that host-plant association at the family level and larval
feeding mode are conservative characters. Transition/transversion ratios
estimated by reconstruction of nucleotide substitutions on the phylogeny
had a range of 2.0-9.3, when different subsets of the phylogeny were used.
The decline of this ratio with the increase in maximum sequence divergence
among taxa indicates that transitions are masked by transversions along
deeper internodes or long branches of the phylogeny. Among transitions,
substitutions of A-->G and T-->C outnumbered their reciprocal
substitutions by 2-6 times, presumably because of the approximately 4:1
(77%) A+T-bias in nucleotide base composition. Of all transversions,
73%-80% were A<-->T substitutions, 85% of which occurred at third
positions of codons; these estimates did not decrease with an increase in
maximum sequence divergence of taxa included in the analysis. The high
frequency of A<-->T substitutions is either a reflection or an
explanation of the 92% A+T bias at third codon positions.
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