Search PubMed⌕ Search

Biomedical subjects

E Didier

Publications and source records attributed to E Didier.

31 records · Page 2Linked to original sources
PubMed1977

[Establishing of an asymmetry index in the germ cell distribution between the genital ridges in the Hubbard chick embryo].

Germ cell numberings inside the gonadic anlages of Hubbard chick embryos allowed us to display these following events: From stage 23 to stage 26, the germ cell number obviously increases. It is for this period that an asymmetry index number, specific for the Hubbard strain is got, thanks to a decreasing in the number of gonocytes colonizing the right gonad epithelium. It is for the same period that the medulla differentiates and becomes populated with gonocytes. Such simultaneous events allow us to suppose that the gonadic colonization might result from some interactions between the germinal epithelium and the underlying mesenchyme.

Animals↗
PubMed1976

[Germinal population of gonads in some chimerical embryos obtained by connecting pieces of japanese quail and domestic chick blastoderms (author's transl)].

The experimental realization of chemerical embryos (Martin's13 technic) permits a quantitative appreciation of the modalities of the colonization of quail gonads by chick germ cells. Results clearly show that nature and origin of the somatic part of the gonad areas settle the characters of the genital ridges populating, and specially the specific index of asymmetry expressed by the percentage of PGC colonizing the right gonad.

Animals↗
PubMed1976

[Quantitative aspects of the colonization of the gonads by germ cells in the quail embryo (Coturnix coturnix japonical)].

A quantitative analysis made on quail embryos coming from 13 isolated parent-couples reveals some significative variations of a genetic origin, between some of the offspring studied: the differences observed concern both the quantitative importance of the colonization of gonads by germ cells and the asymmetrical distribution of PGGs (primordial germ cells) between the two genital ridges. The chronological study of the colonization in the quail shows, as in both the duck and the chick, two periods of rapid and regular increase of the number of gonadic PGC, at stages from 13 to 18 and from 24 to 30 of Hamburger & Hamilton. The distribution of germ cells between the two genital ridges is, at the beginning of the colonization, not very asymmetrical. Between stages 18 and 24 the asymmetry increases and remains stable so that the mean value of D% (percentage of the number of PGC contained in the right gonad) from that moment on is equal to 29-34%. This value is specific for the quail embryo.

Animals↗