Laser irradiation of the chick embryo germinal crescent By MARTHA FEARON MIMS
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چکیده
INTRODUCTION Primordial germ cells have an extra-gonadic origin in the chick embryo. They may be found in the primitive streak or head-process stage, in an area known as the germinal crescent, located in the endoderm anterior and antero-lateral to the primitive streak at the junction of the area opaca and area pellucida (Swift, 1914; Willier, 1937; Reynaud, 1967; Clawson & Domm, 1969). Primordial germ cells are distinctively large and thus are easy to identify (Goldsmith, 1928). Primordial germ cells are migratory. They begin to separate from the endoderm at the definitive primitive streak stage (Clawson & Domm, 1967), are soon found in the lumina of blood vessels (Abdel-Malek, 1950), and are in the tissues of the embryo proper by the cranial flexure stage (Meyer, 1961, 1964). Most primordial germ cells become situated in the gonad primordium, some appear to degenerate, and others are thought to form extra-gonadic islands of germ tissue (Clawson & Domm, 1968). The fate of these migratory giant cells has been in dispute because extirpation of the germinal crescent has generally resulted in the death of the host embryo. The fate of primordial germ cells would be revealed if they could be selectively removed with negligible or no damage to embryonic tissues. The purpose of the present study is to report preliminary results that suggest laser irradiation of the
منابع مشابه
Laser irradiation of the chick embryo germinal crescent.
INTRODUCTION Primordial germ cells have an extra-gonadic origin in the chick embryo. They may be found in the primitive streak or head-process stage, in an area known as the germinal crescent, located in the endoderm anterior and antero-lateral to the primitive streak at the junction of the area opaca and area pellucida (Swift, 1914; Willier, 1937; Reynaud, 1967; Clawson & Domm, 1969). Primordi...
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تاریخ انتشار 2008