【摘要】 妊娠14～17天大鼠胎的十二指肠由复层上皮及其周围的间充质组成。从胚胎第18天开始,间充质向上皮基底面突入,形成原始绒毛;与此同时,杯状细胞和小肠腺的原基亦出现。绒毛表面的杯状细胞数随着胚胎的发育而增多。出生后,随着小肠腺的发育成熟,杯状细胞逐渐减少。从胚胎19天至生后3～4周,绒毛的形状逐渐变化,4周以后与成年鼠基本相同。更多还原

【Abstract】 During 14-17th days, the duodenum of the rat fetus was composed of stratified epithelium and peripheral mesenchyme. On 18th day, the mesenchyme began to protrude toward the basal aspect of the epithelium, resulted in the formation of primary villi. At the sametime, goblet cells and the primordia of intestinal glands appeared. The number of goblet cells,which located at the surface of the villi, increased gradually with the fetus age, whereas after birth the goblet cells decreased with the development and maturation of intestinal glands. From 19th day till 3-4 weeks after birth, the shape of villi changed continuously, and attained to the adult shape in 4th week.更多还原