Table 3 . Urea production by differentiated UC-MSCs in 2D and 3D culture system (ng/mL) .
| Urea secretion | Step 1 | Step 2 | Step 3 | Step 4 |
| 2D | 4.0 | 4.0 | 8.0 | 12.0 |
| 3D | 13.0 | 12.0 | 14.0 | 15.0 |
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.