AND DIABETES 163 



tissues fails to keep up with them. Then the normal 

 alkalinity of the blood falls, and dyspnoea, collapse, 

 and coma begin to appear. 



DIAGNOSIS OF STARVATION. 



It may become very important to know if a patient 

 is or is not obtaining adequate nourishment. This 

 is particularly the case when on account of vomiting, 

 haematemesis, or typhoid fever, mouth feeding has 

 to be restricted or becomes altogether impossible. 

 It is easy to find out. Daily estimates of the urea 

 output will show if the protein absorbed is adequate, 

 and tests for acetone, diacetic acid, and oxybutyria 

 acid will show if the supply of carbohydrate has 

 fallen too low. The normal ratio of ammonia 

 nitrogen to urea nitrogen is about 5 per cent. If it 

 rises to 10, 15, or 20 per cent, there is severe acidosis 

 present, due to starvation, but masked by the am- 

 monia supplied to neutralize it. When the supply of 

 ammonia fails, fatal coma will follow. 



THE ESSENTIAL NATURE OF DIABETES. 



Seeing that it is in diabetics that the most terrible 

 consequences of acidosis are exhibited, it will be 

 well very briefly to consider just in what way the 

 metabohsm has gone wrong in this disease. 



Glycosuria may be experimentally induced in 

 animals by the following means : — 



{a). By puncture of the medulla. — This is perhaps 

 a vasomotor effect, the increased blood-flow washing 

 glycogen out of the liver. Or there may be some 

 interference with secretory nerves to the liver. 



