目的比较改良颈部透光法与导管厘米刻度法、气囊后标记线法、纤维支气管镜（纤支镜）法确定气管导管插入位置的效果。方法采用前瞻性随......

Aim: To determine the effect of oral administration of an aqueous extract from the roots of Lepidium meyenii (maca)on sp......