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.
PR survival in vitro depends on donor age. PR cultures were prepared from postnatal day 5, 7, 9, 11, 13, and 15 retinas of rats. PRs were counted after 24 hr and compared with the total number of seeded cells. PR survival was higher when retinas were taken at 5 d (58% live PRs). Between 9 and 11 d, PR survival decreased dramatically (from 43 to 12%) to become nearly zero (2.5%) at 15 d. Error bars are SEM (n = 3). *p < 0.01; **p < 0.001.
