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Summary The sexual development of 14 girls with non-mosaic monocentric 46,X,iXq karyotype was studied. Seven out of eight girls were found to have immature secondary sexual characteristics and amenorrhoea, a finding greatly contrasting with that in Triplo-X girls. The relative ineffectiveness of the isochromosome Xq in maintaining fertility may be due to the absence of one short arm, which probably also carries a gonadal determinant. Alternatively, the presence of two inactivation sites on one isochromosome may render the gonadal determinants inactive at an important stage in gonadal development. 相似文献
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Summary The PGM3 locus, like the PGM1 locus, is shown to be easily demonstrated in hair sheath cells using starch gel electrophoresis. The discriminating power of the total system (PGM1 and PGM3) on starch gel electrophoresis closely approaches that observed by isoelectric focusing of the PGM1 locus. Family studies of the PGM3 locus variants in hair sheath cells confirm that the alleles responsible are inherited in a Mendelian fashion independent of the PGM1 locus. 相似文献
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Neutralization efficacy of Dey-Engley medium in testing of contact lens disinfecting solutions 总被引:2,自引:0,他引:2
A quantitative assay for the demonstration of neutralizer efficacy was developed to monitor contact lens disinfecting solutions. Adequate neutralization of disinfecting agents is essential to the accurate determination of disinfecting activity with time. This method employed the recovery of small numbers of micro-organisms from neutralizing medium containing a disinfectant. A statistical estimation of significance between treatments demonstrated that Dey-Engley medium (DE; Difco) was generally effective when tested as an agar growth medium with several bacterial test organisms. DE medium from another vendor was less effective, underscoring the need for laboratory quality control and monitoring. DE agar (Difco) adequately neutralized all solutions tested at a 1:20 dilution. The solutions included those containing Dymed (polyaminopropyl biguanide, 0.00005%), chlorhexidine (0.005%), Polyquad (0.001%), chlorhexidine (0.005%) and thimerosal (BP, 0.001%), thimerosal (BP, 0.002%) and Tris(2-hydroxyethyl) tallow ammonium chloride (0.013%), and a solution preserved with 115 ppm benzalkonium chloride (BAK). A modification of this medium was developed which retained virtually all of the neutralizing efficacy for the solutions tested while allowing the use of automated testing procedures. 相似文献
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J. G. Sutton 《Human genetics》1979,47(3):279-290
Summary The existence of four alleles of phosphoglucomutase (PGM1) in human red cell lysates has previously been demonstrated by isoelectric focusing (Bark et al., 1976; Kühnl et al., 1977; Sutton and Burgess, 1978). Experiments are now described in which the position of each of the first-locus (PGM1) and second-locus (PGM2) isoenzymes is defined, thus extending and confirming the original proposal made by Bark et al. 相似文献
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Enzyme variation in Eimeria species of the chicken. 总被引:6,自引:0,他引:6
M W Shirley 《Parasitology》1975,71(3):369-376
A method for the biochemical identification of protozoa belonging to the genus Eimeria is described for the first time. Starch gel electrophoresis of the enzymes lactate dehydrogenase, glucose phosphate isomerase, 6-phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenase from parasite extracts revealed both intra- and inter-species differences when 11 strains representative of 6 species of Eimeria were examined. Oocysts were the most accessible parasite stage for investigation but sporozoites and merozoites of an embryo-adapted strain of E. tenella were also examined for enzyme activity. 相似文献