Diseases of the nervous system / by Judson S. Bury.

  • Judson Sykes Bury
Date:
1912
Catalogue details

Licence: Public Domain Mark

Credit: Diseases of the nervous system / by Judson S. Bury. Source: Wellcome Collection.

    71/856 (page 43)
    quantity of blood, of which a marked instance is the anaemia produced by the narrowing of an artery due to disease in its walls, or to its being blocked by a thrombus or an embolus. A more striking cause of nervous disease is an altera¬ tion in the quality of the blood. This may depend on : (1) A diminution of an excess of a normal constituent of the blood. The most noteworthy example of diminu¬ tion or absence of a normal constituent of the blood giving rise to impaired brain functions is afforded by myxcedema and cretinism, the symptoms of which depend on absence of the thyroid secretion. Then the nervous phenomena of Graves’s disease are ascribed either to an excess of thyroid secretion entering the blood, or to an insufficient quantity of the secretion of the parathyroid gland. Here, too, may be mentioned the lassitude and mental fatigue which result either from an insufficiency of oxygen, or from an excess of carbonic acid and nitrogenous waste products, as well as the stupor, delirium and psychical symptoms which occur in cases of heart failure owing to engorgement of the brain with venous blood. (2) The presence of abnormal constituents in the blood. ITnder this heading are poisons which are intro¬ duced into the body, as alcohol, lead and arsenic, and poisons which are produced within the body, as the toxins of syphilis, tubercle and the specific infectious diseases. These toxins to which the nervous phenomena may be ascribed are the products of micro-organisms, many of which have been distinguished and are well recognised. In the case of chronic degenerative diseases as disseminated sclerosis and amyotrophic lateral sclero¬ sis, and also of some acute nervous affections as acute anterior polio-myelitis and Landry’s disease, it is assumed that they also are set up by poisons, some of which may be the products of bacteria, whilst others are derived from the products of over-fatigue or of abnormal digestion in the alimentary canal, or from the perverted function of some other organ or tissue.