Motta P M, Makabe S
Eur J Obstet Gynecol Reprod Biol. 1986 Sep;22(5-6):271-86. doi: 10.1016/0028-2243(86)90115-2.
Observations by scanning and transmission electron microscopy during ovarian development (from 7 wk until term of gestation) showed numerous germ cells within the superficial epithelial layer covering the ovary. In early stages of differentiation (between 7 and 11 wk), germ cells appeared to be actively migrating to the surface of the ovary by ameboid-like movements. Later, the transfer of the germ cells to the surface epithelium was also occurring passively, as a consequence of an intense proliferation of germ and somatic cells - arranged in clusters and cords - migrating towards the most superficial areas of the ovary. The present evidence suggests that a number of primordial germ cells - as well as oogonia and oocytes - which lie in the superficial epithelium can leave the ovary and ultimately rest freely upon its surface. Elimination of germ cells during differentiation of the ovary in humans was always paralleled by necrosis of oogonia and oocytes and atretic alteration of primitive follicles. The significance of these processes is discussed in relation to the reduction of the pool of oocytes at birth.
在卵巢发育过程中（从妊娠7周直至足月），通过扫描电子显微镜和透射电子显微镜观察发现，覆盖卵巢的表层上皮内存在大量生殖细胞。在分化早期（7至11周之间），生殖细胞似乎通过类阿米巴样运动积极迁移至卵巢表面。后来，由于生殖细胞和体细胞强烈增殖并聚集成团和索状，向卵巢最表层区域迁移，生殖细胞也被动地转移至表面上皮。目前的证据表明，位于表层上皮的许多原始生殖细胞以及卵原细胞和卵母细胞能够离开卵巢，并最终自由地停留在其表面。在人类卵巢分化过程中生殖细胞的消除总是伴随着卵原细胞和卵母细胞的坏死以及原始卵泡的闭锁改变。结合出生时卵母细胞库的减少对这些过程的意义进行了讨论。
