【摘要】 本文报道观察的7周至足月胚胎视网膜的三级神经元及色素上皮的发育情况。锥体杆体外段的盘膜在胎儿7个月时开始形成。新形成的盘膜排列并不整齐;足月时,盘膜平行排列,并与外段长轴垂直。在9个月时,色素上皮层中还未见到含有盘膜的吞噬体。在足月胎儿的色素上皮中,才见到较多含有盘膜的吞噬体。更多还原

【Abstract】 The development of the three sets of neurones and the pigment epithelium of the retina of the human embryos and fetuses, dating from the seventh week to term, were studied at histological and ultrastructural levels.The discs in the outer segments of the rods and cones were recognized at the seventh month. The newly formed discs were not orderly arranged. At term, the discs became parallel to each other and perpendicular to the long axis of the outer segment. At nineth month, no phagocytised discs were seen within the pigment epithelium, but they were discerned inside the cytoplasms of the pigment epithelia of the term fetuses.更多还原