Thirty-two adult SD rats were randomly divided into four groups and there were eight rats in every group: control group(NS group); ALI model group(LPS group); NAC pretreative group(N &L group) and Dex pretreative group(D &L group).

• 将32只SD大鼠随机分成4组：正常对照组(NS组)、ALI模型组(LPS组)、NAC干预组(N&L组)、Dex干预组(D &L组)，后两组分别以NAC(200mg/kg)和Dex(70mg/kg)预处理。