| 1 | The police belted up and went out. | |
| 2 | They occur when there is a breakdown in the integrity of the corneal epithelium. | |
| 3 | If there wereepithelial cells on the root, we could use their nuclei for DNA analysis. | |
| 4 | Beta-carotene converts to the active form of vitamin A, which helps to repair epithelial or skin cells. | |
| 5 | To observe the repair effect of the human plasma FN for the refract ory corneal epithelial defect. |