Methods Seventy five pathogen free Sprague Dawley (SD) rats were randomly divided into three groups (25 in each group),they were control(C),bleomycin(BLM) and dexamethasone (DXM) group.

• 方法 75只SD大鼠随机分为对照组 (C组 )、博莱霉素组 (BLM组 )和地塞米松组 (DXM组 )。