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371.
372.
Evidence that conserved developmental gene-regulatory networks can change as a unit during deutersostome evolution emerges
from a study published in BMC Biology. This shows that genes consistently expressed in anterior brain patterning in hemichordates and chordates are expressed in
a similar spatial pattern in another deuterostome, an asteroid echinoderm (sea star), but in a completely different developmental
context (the animal-vegetal axis). This observation has implications for hypotheses on the type of development present in
the deuterostome common ancestor. 相似文献
373.
Streptococci, actinomycetes, actinobacilli, veillonellae, neisseriae, and lactobacilli were isolated from the anterior fissures
of the second mandibular molar teeth of Sprague-Dawley rats. In individual animals, there were no great differences between
the percentage bacterial composition of plaque collected from discrete sites on different sides of the same mouth. This bilateral
similarity was apparent with each of four diets, irrespective of the cariogenicity of the diet. These findings indicate why
the pattern of carious attack in rats is bilaterally symmetrical. 相似文献
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375.
A M Maszenan R J Seviour B M McDougall J A Soddell 《Journal of industrial microbiology & biotechnology》1997,18(4):267-271
Whole cell protein extracts from strains of the currently recognized genomic species of Acinetobacter, together with those from a range of isolates of several genomic species identified using the Biolog system and obtained
from a biological nutrient-removal activated sludge plant were analysed by SDS-PAGE. The dendrograms obtained after numerical
analysis for the known genomic species generally supported the taxonomic relationships suggested from earlier DNA–DNA hybridisation
data. In some cases the activated sludge isolates identified to genomic species level clustered closely with the corresponding
genomic species reference strains, although isolates 5 and 8/9 were scattered throughout the dendrogram. Considerable variations
were seen in the protein patterns of the 27 different environmental isolates of genomic species 7 that were analysed. Three
unidentified Acinetobacter isolates examined formed their own subcluster.
Received 06 September 1996/ Accepted in revised form 10 December 1996 相似文献
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Twenty-seven pyrimidine-requiring mutants were isolated as suppressors of anarg-3 mutant. All 27 are deficient for ATCase activity and show linkage to thecol-4 marker located on linkage group IV. Analyses of prototroph frequencies resulting from crosses of the new mutants to previously mappedpyr-3 mutants indicate that this functional type ofpyr-3 mutant is restricted to one region of the genetic map. Complementation studies with 11 of the new mutants further extend and subdivide the complementation map of thepyr-3 locus.This work was supported in part by National Institutes of Health, Public Health Service Grant GM 15137-01 and by National Science Foundation Grant GB5998. 相似文献
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