Hirosuke Kobayashi

Estimation of the distribution profile of airway resistance in the lungs

The distribution profile of resistance in a series lung model consisting of airways of 23 generations with alveoli was estimated in 10 healthy subjects and 7 subjects with chronic pulmonary emphysema. Forced oscillation was applied to the subjects at the mouth using a complex wave composed of sine waves at frequencies through the range 4 to 20 Hz in 1-Hz steps. The pleural pressure was measured with a catheter-tip micromanometer, which was installed in an esophageal balloon. The frequency dependency of the pulmonary impedance was analyzed using a penalty function method, and a stable estimate of the distribution profile of resistance in the lungs was thus obtained. The central airway resistance (defined as the resistance from generation 0 to generation 7) was estimated as 1.18 +/- 0.37 cm H2O/liter/sec in the healthy subjects and 1.03 +/- 1.13 cm H2O/liter/sec in the subjects with chronic pulmonary emphysema. The peripheral airway resistance (defined as the resistance from generation 8 to generation 23) was estimated as 0.06 +/- 0.03 cm H2O/liter/sec in the healthy subjects and 6.38 +/- 3.77 cm H2O/liter/sec in the subjects with chronic pulmonary emphysema.

Counter-current blood flow in tissues: protection against adverse effects.

In hypoxia, the tissue counter-current can thus, by virtue of the Bohr effect, increase tissue Po2 and thus tissue oxygenation. In hyperoxia, on the other hand, the counter-current system, acting as a diffusion shunt, can protect the tissue against adverse O2-toxic effects. It thus appears, that the counter-current system is advantageous for O2 supply to tissues.

Uneven distribution of ventilation-perfusion ratios in lungs estimated by a modified newton method

AbstractThe uneven distribution of ventilation—perfusion ratios (

Manufacturing device and manufacturing method of medical purpose dialysis fluid

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A Case of Legionnaires' Disease Cured with a Combination of Erythromycin and Steroid Therapy

) in diseased lungs is the major cause of arterial hypoxemia. Farhi and Yokoyama (1967) and Yokoyama and Farhi (1967) were the first who used physiologically inert gases as indicator gases to assess the uneven distribution of

Separation method of albumin from biomolecule bound to albumin

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