An experimental inquiry into the nutrition of animal tissues / by William Marcet.

  • Marcet, W. (William), 1828-1900.
Date:
1874
Catalogue details

Licence: Public Domain Mark

Credit: An experimental inquiry into the nutrition of animal tissues / by William Marcet. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    of matter is gradually overcoming that force which belongs exclusively to life, the nature of which is still a mystery; and the slow ebb of life in phthisis is a gradual return to a purely physical condition. ON PULMONARY TISSUE AND ITS NUTRITION IN PHTHISIS. My inquiries into the chemical changes pulmonary tissue undergoes in phthisis have led to some very interest- ing results. In health the lungs consist of a tissue, which from its structure, allows readily of expansion and contraction; this tissue becomes thoroughly permeated with air during respiration, the oxygen of which diffuses through the substance of the lungs and the pulmonary capillary vessels into the blood, the carbonic acid being eliminated from the blood by a similar process. This gaseous diffusion can only take place so long as the soft and delicate walls of the capillary vessels and pulmonary air-vesicles remain physically unaltered; if they should become hardened or changed in any other way, the diffusion of the gases through their substance must be interfered with or entirely checked. Now in the most common form of phthisis, as shown by Dr. Sanderson, the process begins by a new growth of the interstitial tissue of the pulmonary honey- comb, having its seat in the very walls of the blood-vessel. Even at an early stage, the effect of this is not only to diminish the circulation of blood in the affected part, but to render the pulmonary capillaries more and more unfit for the exchange of gases, by diffusion, between the blood and the inspired air. Eventually the air-cells or alveoli in their turn become filled up with a solid material, losing completely their fitness for respiration. Then the tissue softens and breaks down, apparently from the loss of the colloid state of the consolidated pulmonary tissue. It is this last stage which is usually observed after death; and the pulmonary tissue I have submitted to analysis was mostly in that condition. The method of analysis I adopted was precisely the same as that which had been applied to flesh and healthy pulmonary tissue.