Serum docosahexaenoic acid as a predictor of hospital readmission in chronic obstructive pulmonary disease exacerbation: a retrospective cohort study血清二十二碳六烯酸作为慢性阻塞性肺疾病急性加重再住院的预测因子:一项回顾性队列研究PeerJIF2.42026-02-190PRE