Rossdale P D, White S
J Reprod Fertil Suppl. 1975 Oct(23):673-80.
Forty-eight lungs from fetal and neonatal horses were examined for pressure-volume relationships between pressures of 0 and 40 cmH2O. The inflation-deflation curves obtained were analysed by four different methods and the stability of the lung assessed in terms of hysteresis, stability indices and volume of air retained at maximal pressure (Vmax). Differences in the shape of the deflation curve between ventilated and non-ventilated lungs were similar to findings in other species. It is postulated that breathing alters lung-tissue elasticity during the neonatal period, as demonstrated by a significant increase in Vmax in specimens from foals breathing for more than 24 hr compared with those from stillborn foals or those aged less than 24 hr. Also, stability indices, such as those expressed by the % of air retained in the lungs on deflation from Vmax to 10 or 5 cmH2O pressure, are related to interfacial factors.
对48个来自胎儿和新生马的肺进行了检查，以研究压力在0至40厘米水柱之间时的压力-容积关系。通过四种不同方法分析所获得的充气-放气曲线，并根据滞后现象、稳定性指数以及在最大压力时保留的空气量（Vmax）来评估肺的稳定性。通气肺和未通气肺放气曲线形状的差异与其他物种的研究结果相似。据推测，呼吸会在新生儿期改变肺组织弹性，这表现为与死产驹或年龄小于24小时的驹相比，呼吸超过24小时的驹的标本中Vmax显著增加。此外，稳定性指数，如从Vmax放气至10或5厘米水柱压力时肺中保留的空气百分比所表示的指数，与界面因素有关。
