Methods This study was established in serum-free condition. The effects of epidermalgrowth factor (EGF), bovine pituitary extract (BPE), and ethanolamine (Etha) on the DNA synthesisof human epidermal cells were determined by (3H) thymidine incorporation.

• 方法采用无血清培养系统，以3H－TdR掺入法测定表皮生长因子（EGF）、牛垂体提取物（BPE）和乙醇胺（Etha）对人表皮细胞DNA合成的影响。