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目的了解人胚胎食管上皮的组织发生。方法电镜和光镜观察。结果７周（５５ｄ）的食管上皮为复层柱状，有２～３层细胞。表层柱状细胞有稀疏的微绒毛，少数具有纤毛。１２～１７周时由３～６层细胞组成，表面多为柱状纤毛细胞，柱状的无纤毛细胞开始变矮。２１～２９周时上皮增至４～１０层，表面的纤毛柱状细胞与立方细胞或梭形的无纤毛细胞在形态上的区别更为明显，它们皆分片分布。２６周以后纤毛细胞逐渐减少。新生儿时上皮大多数为典型的复层鳞状，最厚处达１５层细胞，少量柱状纤毛细胞“岛”分散于无纤毛细胞之间。结论３～６月胎儿食管上皮中，复层纤毛柱状上皮占大多数。在食管肌层发育完善以前，纤毛可能有助于胎儿吞咽羊水。
Objective To understand the tissue development of human embryo esophageal epithelium. Methods Electron microscopy and light microscopy. Results The esophageal epithelium of 7 weeks (55 days) was stratified columnar with 2 ~ 3 layers of cells. Surface columnar cells have sparse microvilli, a few with cilia. From 12 to 17 weeks by the 3 to 6 layers of cells, the surface mostly cylindrical ciliated cells, columnar ciliated cells began to become shorter. 21 to 29 weeks, the epithelium increased to 4 to 10 layers, the surface of the ciliated cells and cubic cells or spindle-shaped ciliated cells in the morphological differences are more obvious, they are distributed in fragments. After 26 weeks, ciliated cells gradually decreased. Most newborn epithelium is a typical stratified squamous, the thickest up to 15 layers of cells, a small amount of columnar ciliated cells “islands” scattered between ciliated cells. Conclusions In 3 ~ 6 months fetus esophageal epithelium, stratified ciliated columnar epithelium accounted for the majority. Cilia may help the fetus to swallow amniotic fluid before development of the esophageal muscle layer is complete.