【摘要】 作者用“直接法”对成都市正常男女青少年628例作了肺量图平均通过时间(MTT)和部分平均通过时间(MTTp)测定与分析。结果表明:MTT和MTTp均随其年龄增长而加大,并随肺内容积衰减而延长;用力肺活量-时间曲线并非单指数函数;比平均通过时间与年龄呈高度负相关,能反映肺弹性回缩压和气道传导率在青少年期间的增长情况。更多还原

【Abstract】 The mean transit time(MTT) and par-tial mean transit time(MTT_p)were measu-red and analysed by "direct method" in628 cases of normal adolescents in Cheng-du. Tbe results showed that both MTTand MTT_p were increased with age andprolonged with the decay of lung volume.Besides, the FVC-t curve was not singleexponential in nature. The specific meantransit time (SMTT) was introduced bycorrecting MTT with 0.5 FVC and repre-sented tbe MTT when unit volume of gaspassed througy just at tha lung volume.SMTT was highly negatively correlatedwith age.This reflected tbo developmentand growth of the lung recoil and airwayconductance in adolescents.更多还原