Kundurović Z
Institut za histologiju i embiologiju, Medicinski fakultet Sarajevo.
Med Arh. 1995;49(3-4 Suppl 1):25-7.
The respiratory system consists of morphologically and functionally distinct sub-divisions-the air-conditioning part and respiratory portion is were O2 and CO2 exchange actually occurs across the delicate, very thin walls of the pulmonary alveoli. The final bifurcation of bronchiole yields terminal bronchiole. The epithelium is gradually reduced from ciliated columnar in the larger bronchioles to ciliated or non-ciliated low cuboidal in the terminal segment. Here non-ciliated Clara cells are plentiful. Only under EM one can clearly identify the lining cells of the alveoli: type I are squamous pneumocytes, type II are large granular alveolar cells and macrophages (dust cells). The hallmarks of pneumocytes type II are the numerous osmiophilic, lamellated inclusion bodies. In TEM there is evidence connecting these bodies with the production of stabilizing surface active material, which prevents the collapse of the alveoli; colled surfactant, different from that of the Clara cells.
呼吸系统由形态和功能上不同的部分组成——空气调节部分和呼吸部分，氧气和二氧化碳的交换实际上发生在肺泡的薄壁上。细支气管的最终分支产生终末细支气管。上皮细胞从较大细支气管中的纤毛柱状逐渐减少到终末段的纤毛或无纤毛的低立方状。这里有丰富的无纤毛克拉拉细胞。只有在电子显微镜下才能清楚地识别肺泡的衬里细胞：I型是扁平肺细胞，II型是大颗粒肺泡细胞和巨噬细胞（尘细胞）。II型肺细胞的特征是有许多嗜锇性板层包涵体。在透射电子显微镜下，有证据表明这些小体与稳定表面活性物质的产生有关，这种物质可防止肺泡塌陷；称为表面活性剂，与克拉拉细胞的不同。
