Clinical characteristics and outcome analysis of pulmonary nocardiosis in southern China: a two-center retrospective study oleh Li-Da Chen, Hong-Yuan Li, Jian-Jun Xie, Miao-Fen Hu, Xiang-Xing Chen, Zhi-Ming Cai, Li Lin, Xiao-Bin Zhang, Gong-Ping Chen, Kai-Xiong Liu