云在璇現旁六寸,大肠巨骨下二骨; 《灵枢·本输》:“肺出于云门。” 《针灸大成》:“云门治咳逆上气,胸中烦满。” In classical Chinese medicine, Yunmen (LU-2) is regarded as the point where Lung Qi emerges, making it essential for regulating respiration and clearing chest congestion.