Table 2

Preservation of serum in freezer

Preservation EGF (ng/ml)Vitamin A (μg/dl)TGF-β1 (ng/ml)
Initial day0.61 (0.06)52.6 (12.2)53.9 (4.7)
1 month 0.53 (0.03)49.1 (11.3)53.7 (4.8)
3 months0.53 (0.06)48.3 (10.3)51.4 (5.9)