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711.
Accurate diagnosis of mosaicism in amniotic fluid cell cultures represents a major problem. If insufficient cells are analysed, true fetal mosaicism may go undetected. False-positive diagnosis is also possible since a second cell line may arise in vitro and not reflect the true fetal genetic constitution. These difficulties apply to both flask and in situ culture techniques, to varying degrees. The relative accuracy of flask versus in situ culture techniques in excluding mosaicism was determined by statistical analysis of experimental data from ten pairs of mixed male-female amniotic fluid specimens. The data support the idea that the majority of in situ colonies are independent of one another. The following conclusions are drawn: (1) analysis of a single metaphase from a number of different colonies enhances the confidence for excluding mosaicism; (2) analysis of more than one cell per colony offers little advantage; (3) exclusion of a given level of mosaicism requires analysis of fewer metaphases using the in situ method; (4) the confidence for excluding mosaicism is high with both in situ and flask techniques, using the provided guidelines; and (5) it is shown that the two-stage approach used by many laboratories is currently the most efficient way to exclude mosaicism. 相似文献
712.
The index patient is a female fetus in which prenatal diagnosis of 8p trisomy was established after amniocentesis at 16 weeks of gestation. This fetus was the unbalanced product of a maternal translocation of 5q/8p (karyotype: 46,XX,t(5;8)(q35;pl 1). Internal malformations include an anomalous lobature of the right lung, a little and high atrio-ventricular communication, and an anomaly in the number and shape of the aortic semilunar valves. The possible relationship between the phenotype and the chromosomal abnormality is briefly discussed. 相似文献
713.
This research was supported by a grant from the National Council for Research and Development, Israel, and the KFK, Karlsruhe, Germany. 相似文献
714.
Dihydrorhodamine 123: a new flow cytometric indicator for respiratory burst activity in neutrophil granulocytes 总被引:13,自引:0,他引:13
This work was supported by DFG SFB 0207, project G 6. 相似文献
715.
We are very grateful to A. Gessner for his great help in the construction of the apparatus and A. Meyer for performance of some pressure bomb experiments. This work was supported by grants of the Deutsche Forschungsgemeinschaft (Forschergruppe Ökophysiologie) to U.Z. and O.L.L. 相似文献
716.
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719.
A syncytiotrophoblast-associated antigen identified by the monoclonal antibody (McAb) H315 is detectable on the surface of a low proportion of peripheral blood cells in pregnant women, raising the possibility of a new approach to prenatal diagnosis of genetic disorders. We aimed at verifying the trophoblastic origin of H315+ cells and their use for prenatal diagnosis of β-thalassaemia. H315 + cells were separated from the peripheral blood of pregnant women: the DNA obtained from these cells in two selected cases was shown to have genetic markers indistinguishable from those of the mother and definitely different from the fetus. Our results suggest that H315 antigen is expressed by maternal cells and that prenatal diagnosis on peripheral blood of the mother using H315 McAb is not feasible. 相似文献
720.