epithelial cell cast

例句：

1. 1.The skin is made up of several layers, including the epidermis and the dermis.
   皮肤由几层组成，包括表皮和真皮。
2. 2.The epithelial cells are responsible for producing the protective barrier on our skin.
   上皮细胞负责在我们的皮肤上形成保护屏障。
3. 3. The study found that the epithelial cells in the lungs were damaged during the infection.
   研究发现，肺部的上皮细胞在感染期间受损。