【摘要】 为了探讨弦线时间常数（τｃｈ）和 Ｆ Ｖ 曲线形状在检查吸烟者小气道功能中的意义，作者对１１６ 例被动和轻、重度主动吸烟者进行了常规肺通气功能τｃｈ 和 Ｆ Ｖ 曲线形状检查。τｃｈ 用 Ｋｎｕｄｓｏｎ 方法计算，τｃｈ ＝ Ｖ／· Ｖ 。结果：凸型 Ｆ Ｖ 曲线分布随吸烟程度而上升，重度吸烟组和凸型 Ｆ Ｖ 曲线的τｃｈ ５０ 均延长到预计值的 １３０％ ，轻度吸烟组τｃｈ５０ 延长到１２０％ 。反映吸烟者小气道功能已有不同程度障碍，提示τｃｈ５０ 是检查小气道功能敏感而特异的指标。与前测 Ｃ Ｏ Ｐ Ｄ患者比较，其τｃｈ７５ 、τｃｈ５０ 、τｃｈ２５ 均随病情加重而延长，反映大小气道都遭累及。提示τｃｈ ５０ 对小气道功能的特异性以及 τｃｈ 在 Ｃ Ｏ Ｐ Ｄ 患者随病情加重而延长的规律性，对病情诊断具有临床意义，值得推广应用。更多还原

【Abstract】 To study the significance of chord time constant (τ ch ) and F V curve configuration in testing small airway function for smokers, the routine ventilatory functions, chord time constant (τ ch ) and F V curve configurations were studied in 116 passive and active (light, heavy )smokers. The τ ch was calculated with Knudson′s method, τ ch =V/·V.Results:The distribution of convex type rose with the degree of smoking. The τ ch50 in heavy smokers and convex F V curve prolongated to 130% of predicted value; τ ch50 in light smokers prolongated to 120%. These reflected that there were different degrees of disturbance in small airway functions of smokers and suggested that τ ch50 should be a sensitive and specific index for testing small airway functions. On the other hand, the τ ch75 , τ ch50 and τ ch25 by the present authors previously measured in patients with chronic obstructive pulmonary diseases (COPD) all prolongated with the severity of the disease, which reflected that both large and small airways were affected. Therefore it is concluded that in terms of clinical implications the specificity of τ ch50 for small airway functions and the prolongation of τ ch with the severity of COPD are useful indexes.更多还原