text_1: 非手术 组 2 例 死亡 是 由 心跳 呼吸 骤停 引起 , 手术 组 1 例 死亡 是 由 肺栓塞 ( 术后 , 化疗 前 ) 引起 .
  
text_2: two deaths in the no @-@ surgery group were due to cardiopulmonary arrest , and one death in the surgery group was due to a pulmonary embolus ( postoperative , prechemotherapy ) .
  