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Genetic polymorphism of complement component C8 总被引:1,自引:1,他引:0
S. Rogde B. Mevåg P. Teisberg T. Gedde-Dahl Jr. F. Tedesco B. Olaisen 《Human genetics》1985,70(3):211-216
Summary Extensive genetic polymorphism of complement component C8 was demonstrated by isoelectric focusing of serum or plasma samples followed by immunoblotting procedures. Using these methods, we could detect both - (C81) and (C82) chain polymorphisms in the same gel. Two-dimensional (2D) electrophoresis of C8 immunoprecipitates was used to obtain further information of the C8 patterns. Evidence was obtained that the C81 polymorphism resides in the structural gene of the C8 chain. Both C8 systems show autosomal, chiefly codominant inheritance, and the distribution of phenotypes agrees with the Hardy-Weinberg equilibrium. Our findings suggest at least five different alleles in the C81 system; the gene frequencies of the two most common ones, C81
*A and C81
*B being 0.59 and 0.39, respectively. In C82 we found evidence for at least three codominant alleles, the gene frequencies for the two most common ones, C82
*B and C82
*A being 0.94 and 0.05, respectively. In addition, family studies disclosed the existence of a null allele, C82
*
Q0. 相似文献
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Summary Bioleaching of manganese (IV) oxide with Thiobacillus thiooxidans has been studied in media with and without sulfur, ferrous sulfide and ferrous sulfate. The knowledge of the role played by the bacteria and the reducing substances suggest that the leaching of manganese (IV) ores through the use of thiobacteria is only justified when suitable amounts of sulfur or metal sulfides are present. 相似文献
7.
The addition of a surfactant agent (Tween 80) to a medium containing sulphur and a culture of Thiobacillus thiooxidans increased the attachment of bacteria to sulphur, the rate of sulphur oxidation and sulphuric acid production. This acid was used to dissolve phosphorus from calcium phosphate. The yield was higher than reported for other microorganisms although dissolution was not increased significantly by Tween addition. 相似文献
8.
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.
相似文献
9.
S. Martinoia M. Meloni M. T. Parodi M. Tedesco C. Ciccarelli M. Grattarola 《Cytotechnology》1993,11(Z1):S86-S88
A silicon microsensor (ISFET — Ion Sensitive Field Effect Transistor) has been used to detect the metabolism of a cell population cultured on a coverslip and positioned close to the sensor surface. The system output is analyzed as a function of cell density. 相似文献
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