This is normal lung microscopically. The alveolar walls are thin and delicate. The alveoli are well-aerated and contain only an occasional pulmonary macrophage (type II pneumonocyte).

• 正常肺显微镜显示肺泡壁比较薄弱。肺泡内充满空气,有肺巨噬细胞(II型上皮细胞)。