CONTENTS. 



PAOB 



INTRODUCTION i 



CHAPTER I. 



DIGESTION AND ABSORPTION OF PROTEINS 4 



SECTION 



1. General Methods of Investigation - 4 



2. Gastric Digestion - 5 



3. Gastric Absorption - 7 



4. Intestinal Digestion - - 8 



5. Intestinal Absorption 9 



6. Absorption of Undigested Protein from the Intestine - - 12 



7. Fate of Parenterally Introduced Protein - 13 



CHAPTER II. 



PROTEIN REGENERATION - - 16 



SECTION 



1 . Are Proteoses or Peptones found in the Blood ? - 1 6 



2. Fate of Protein after Absorption - 18 



3. The Nature of the Absorbed Material - 24 



4. The Hypothesis of Freund - 27 



5. Plastein Formation - 29 



6. Synthesis in the Gastric and Intestinal Mucous Membranes - 31 



7. Synthetic Experiments in vitro - - 32 



8. The Role of the Leucocyte - 33 



CHAPTER III. 



FEEDING EXPERIMENTS WITH ABIURET PRODUCTS OF DIGESTION - 35 



SECTION 



1. The Value of Abiuret Products of Digestion - 35 



2. The Value of Asparagine - 41 



3. The Fate of Amino Acids - 44 



4. The Administration of Amino Acids as a Test of Functional 



Activity - 46 



5. Mode of Catabolism of the Amino Acids - 47 



6. Sugar Formation from Amino Acids - - 48 



CHAPTER IV. 



DEAMINIZATION - "49 



SECTION 



1. General - 49 



2. The Presence of Ammonia in the Portal Blood - - - 51 



3. Deaminizing Capacity of Tissues - 52 



4. Evidence from the Fate of Amino Acids - 54 



5. Deaminization in the Lower Forms of Life - 55 



CHAPTER V. 



INFLUENCE OF THE FOOD ON THE COMPOSITION OF THE TISSUES - 56 



SECTION 



1. Evidence from Feeding Experiments - - 56 



2. Composition of the Tissues - - 58 



3. Growth of Moulds - 60 



4. Variations in the Composition of Proteins - 60 



5. Variations during Development - 61 



6. Transmutation of Amino Acids - - - - 61 



