Text-book of nervous diseases : for the use of students and practitioners of medicine / by Charles L. Dana.

  • Charles Loomis Dana
Date:
1916
Catalogue details

Licence: In copyright

Credit: Text-book of nervous diseases : for the use of students and practitioners of medicine / by Charles L. Dana. Source: Wellcome Collection.

    19/662 (page 1)
    Diseases of the Nervous System CHAPTER I GENERAL ANATOMY, PHYSIOLOGY, AND CHEMISTRY In studying the phenomena of life in the human body, we as physicians first learn about its normal structure and functions. We then note the new phenomena which develop when disease comes on, the causes which produce them, and the anatomical changes lying back of them; we group our facts and give the disease a name. Lastly we apply the methods by which the disorder can be expelled and future attacks prevented. In fine, we investigate our subject just as we do that of any branch of natural history. Our study divides itself, therefore, into Normal anatomy and physiology. Etiology, a study of the causes. Symptomatology, a study of the morbid phenomena. Pathology, under which we include a study of the morbid anatomy and physiology. Diagnosis, or the method of recognizing and separating out the dif¬ ferent groups of diseases. Prognosis, a forecast of the future course of the malady. Treatment and prophylaxis. GENERAL ANATOMY The nervous system is derived from the ectodermal germ layer of the developing ovum, and its constituents are modifications of epithelial cells. These cells in the embryo are of two kinds: neuroblasts, which develop into nerve-cells and fibres; and spongioblasts, which develop into a supporting structure called neuroglia (His). The nervous system is composed of: (а) Neurons, which form the nervous tissue proper, and are made up of nerve-cells, with their processes, one of which becomes an axis cylinder; and neuroglia. (б) Accessory tissue, consisting of connective tissue, blood-vessels, lymphatics, and epithelium. 1