人胎阑尾组织发生的光镜和SEM观察

收集20～32周人胎,在光镜和扫描电镜(SEM)下观察阑尾的组织发生。20周阑尾腔小壁薄、管壁四层结构与成人相似,绒毛、肠腺、内分泌细胞和杯状细胞已出现。固有膜含丰富的弥散淋巴组织,并有许多淋巴小结突人粘膜下层;固有膜含少量不规则的肠腺,多数埋于淋巴组织中30～32周淋巴小结数量增多,但未见生发中心出现。SEM下观察20周后阑尾内的内分泌细胞有表面光滑和粗糙两类;20～28周阑尾淋巴组织的细胞间隙充满小囊和小泡,细胞表面有短而不规则的微绒毛。

Observation on Appendix Histogenesis of Human Fetus with Light and Scanning

The human appendix histogenesis within 20-32 weeks was observed under light andscanning electron microscopes after the appendices were cut off from newly-aborted fetus.The appendicesof 20 weeks showed small lumen and thin wall and the structures of four layers of the wall were similar tothose of the adults,there were small amounts of irregular intestinal glands and abundant lymphatic tissuesin the lamina propria.The numbers of lymphatic nodules increased gradually from 30 to 32 weeks,but noemergence of germinal center was observed.There were two kinds of enteroendocrinc cells in theappendices older than 20 weeks,one was with smooth surfaces,the other with rough surfaces.At the age of20-28 weeks,many follicles and vesicles filled the intercellular space of lymphatic cells and on the surfacewere there many short and irregular microvilli.