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Role of Diffusion Screening in Pulmonary Diseases

  • Bernard Sapoval
  • Marcel Filoche
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 605)

It has been shown recently that the acinus is only partially efficient in normal conditions. This is due to a “screening effect” governed by the relative values of the oxygen diffusivity and the membrane resistance as well as design and size of the acinus. These effects depend on the fraction of the acinus in which gas transport is governed by diffusion, then on the location of the convection-diffusion transition. It is shown that these screening effects gives to respiration at rest a partial protection against several types of pulmonary diseases. This is true for mild emphysema, mild asthma or COPD and mild edema. In contrast, under exercise respiration, the acinus is totally efficient and the protective effects linked to the existence of screening do not exist anymore.

Keywords

Screen Effect Membrane Resistance Mild Asthma Oxygen Flux Entrance Velocity 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer 2008

Authors and Affiliations

  • Bernard Sapoval
    • 1
    • 2
  • Marcel Filoche
    • 1
    • 2
  1. 1.Ecole PolytechniqueC.N.R.S., Laboratoire de Physique de la Matière CondenséePalaiseauFrance
  2. 2.Ecole Normale SupérieureC.N.R.S., Centre de Mathématiques et de leurs ApplicationsCachanFrance

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