An improved EBC collecting system was used to collect EBC, and the ROS concentration in EBC was measured using a DCFH2-HRP chemical fluorescent method.

• 本研究以一个改良后的EBC采样系统进行EBC的收集，使用DCFH2-HRP化学萤光法来侦测呼出气体凝结液中ROS浓度。