CONTENTS. ix 



PAGE 



THE NUCLEINIC ACIDS , 94 



The pyrimidin derivatives 98 



The purin derivatives 100 



THE UREIDS 104 



THE KREATINS 107 



THE PTOMAINS . 108 



CHAPTER VI. 



THE FEEMENTS. 



General properties 112 



Chemical composition and general reactions 115 



Mode of action 116 



Classification 116 



The proteolytic ferments 117 



The amylolytic ferments 117 



The inverting ferments 117 



The lipolytic ferments 117 



The ureases 117 



Ferments which transform amino-acids into amides 117 



The histozyme of Schmiedeberg 118 



Ferments which cause the cleavage of glucosides 118 



Thenucleases 118 



Ferments which split off carbon dioxide 118 



The oxidation ferments 118 



The coagulating ferments 119 



Reducing ferments 119 



Thekinases 119 



CHAPTER VII. 



THE DIGESTIVE FLUIDS. 



THE SALIVA 120 



General characteristics 120 



Amount 120 



Chemical composition 121 



Ptyalin 122 



Mucin 124 



Sulphocyanides 125 



Nitrites 125 



Extractives . 126 



Mineral constituents 126 



Gases 126 



THE GASTRIC JUICE 126 



General considerations 126 



Amount 126 



Chemical composition 127 



Acidity of the gastric juice 127 



