Digestion and Metabolism

Englebert Taylor Alonzo

Description

Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. The author is convinced from perusal of current medical writings in this country that there is need among American physicians for a work presenting the subjects of Digestion and Metabolism in a popular manner, without technical details, and from the standpoint of dynamics rather than from that of analytical statics usually occupied by text books of physiological chemistry. He has rewritten in the form of a concise and systematic treatise the substance of his lectures in this field. No effort has been made to prepare an encyclopedic survey or a methodic synopsis of the very extensive literature of these subjects, but rather to offer a practical interpretation of them in their present state of development. The aim of the book is to describe the chemical changes in normal and abnormal digestion, and explain the known metabolic modifications that food materials undergo within the body. This understanding makes for comprehension of the pathology of diseases that may be termed metabolic - such as gout, diabetes, nephritis, autointoxication and the results of indigestion. In a word, the aim is to give the student and practitioner a working knowledge of just what is known to occur in the chemistry of the normal body and also of the changes concerned in many widespread and important diseases. Variations and findings in morbid states have been everywhere considered. The student and practitioner of the art and science of medicine will gain the most definite idea of physiological processes and chemical functions if they View them as a moving picture; in other words, if they will consider them dynamically rather than statically. The experimental method alone has enabled us to acquire the larger portion of our present knowledge of digestion and metabolism. Ability to think in the terms of the experimental method is essential to an under standing of these subjects. The student and physician need more than facility in method, invaluable as this is. They need the dynamic concept o

Sujets

• Sciences et techniques
• Biology

Informations

• Publié par: Forgotten Books
• Date de parution: 27 novembre 2019
• Nombre de lectures: 0
• EAN13: 9780243825240
• Langue: English
• Poids de l'ouvrage: 17 Mo

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author is convinced from perusal current medi al writings in this country that there need among American physicians for a work resenting the subj ects igestion and etab olism in a popular manner without te hnical details and from the standp oint dynamics rather than from that of analytical statics usually occupie d by text books physiological chemistry H ae has rewritten in the form con ise and systematic treatise the substance his lectures in this fihas been made to prepare an encyclopedic surveyeld No e fort a methodic synopsis the very extensive literature of these subj ects b ut rather offer a practical interpretation of them in their present state d evelop ment The aim the b ook to describ e the chemical chang s in normal and abnormal digestion and explain the known metabolic mod ifications that food material s undergo ithin the body This understanding makes for comprehension the pathology diseases th t may b e termed metab olic such as gout diabetes nephritis autointoxication and the results indigestion In a word the aim is to give the student and practitioner a working knowledge j ust what is known to occur in the chemistry the normal body and also the changes concerned in m any widespread and important diseases ariations andfierednd ings in morbid states have been everywhere consid The student and practitioner of the art and science of medici ne will gain the most d efiphysiological processes and chemicalnite idea functions if they View them as a moving picture in other word s if they will onsider them dynamically rather than statically The experimental method alone enabled u s to acquire the larger portion present kno ledge digestion and metab olism Ability to think in the terms the experimental method essential an under standing these subj ects The student and physician need more than facility i n method i nvaluabl e as this is They need the dynamic concep t function on which to found a dynami c conception disease The defifun tionnition of experiment is fundamental to the concept

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whi h i n turn is the foundation the und erstanding d isease The foll owing pages attempt with the minimum of techni al d etails to o fer a presentation and interpretation the broad functions diges tion and metab olism from the standpoint hemical dynamics The proper introd uction ref rences to literature i s very difficul annot emphasize here and rej ect there without entering into the d etails of the several investigations in order scientifiustifycally to j acceptance omission reported d ata Thefirst third this work was written with full references t o liter ture It was then apparent that the references made up a third the text The direct references occupied much spa e and the necessary discussion of them for ed the incl usion mu h te hnical detail The work was then frankly recast into a direct interpretation of the subj ect matter necessarily some what d ogmatic and representing in part simply the j udgment of the author The method procedure has been to let the facts p oint the way theory though in some instances it has seemed necessary to appeal to theory to aid in the interpretation of facts The newer nomenclature ferments has b een employed With consid erations phil ol ogical warrant an arbitrary distinction has been mad e i n the terms derived from glycogen and glucose Thus glycogenesis and glycolysis mean respectively the formation glycogen from glucose and the cleavage glycogen into glu ose glucolysis and glucosuria mean the destruction glucose and the presence of glucose in the urine respectively etc I n the matter chemical nomenclature an extreme position has been avoided

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food stu s are d ivided into three natural group s carb ohydrates fats and proteins These are all energy arrying materials substances from which tissues are formed with wh ich t ey are maintained and through whose combustion th e heat necessary for the life of h igher animal s i s derived The inorganic salts are not to b e regarded as foods indispensable as they are to the life of ell s They combine with the organic components tissues and they maintain physico ch emical conditions under which living cell s displ ay the ch emical fu nction s life Wh ile they are indispensable to tissue structure and to tion the term food would best be restricted to substances th at car ry energy into the organism An elaborate chemical des ription Of food stuffs does not fall within the scop e this treatise and only such description will b e given as seems needed the explicit purpose th is work

Under th e term carb ohydrate s meaning carb on combined with hydrogen and oxygen in the relations that hold in water we include all forms sugars saccharid s as they are termed The saccharid s are d ivided into four main classes di and and celluloses The primary sugars are the simple sub stances from which all the l arger carbohydrates are formed When two three or even fou molecules primary sugar are combined we speak Of a d i tri the polysaccharid an indeterminate though l arge number molecules of primary sugar combine to form mole cule The celluloses are still l arger molecul ar dimensions The are Of small molecu ar dimension very soluble sible not dissociated in the ordinary sense of the term usually typically crystalloidal and their solutions present surface tension and high osmotic pressure The disaccharid s are al so crystalloidal very soluble d iffusibl e and their solution s present surface tension and hi h