212 SYSTEMATIC TESTING OF URINE. 



Tyrosin in the urine has the same source as in diges- 

 tion the decomposition of protein compounds. It is im- 

 probable that it comes from the intestine, but from other 

 parts of the system. It is indicative of retrograde met- 

 amorphosis of the nitrogenous tissues. Thus, it is present 

 in acute atrophy of the liver, in suppurative processes, and 

 in phosphorus poisoning, which is accompanied by degen- 

 eration of the liver. Leucin is often found at the same 

 time. (Plate II, 12, ft.) 



FAT. 



The appearance and significance of fat in the urine 

 (lipuria) has already been discussed. 



* 



SYSTEMATIC TESTING OF TJKINE. 



In the systematic testing of urine the course is often 

 varied, as the symptoms may point to the likelihood of 

 the presence or absence of certain substances. The quan- 

 titative tests may be made use of or not according to 

 circumstances. The following are the determinations 

 which are most important, with the tests which may be 

 employed : 



1. Amount passed in twenty-four hours. 



2. Color ^ XT . 



f Normal or abnormal. 



QCy (If the latter, what is the cause? 



4. Odor J 



5. Chemical reaction. 



If alkaline, is it from NH 3 or fixed alkalies? 

 (Experiment 338). 



6. Specific gravity at 60 F. (15.5 C.). 



7. Urea: percentage and amount in twenty-four 



hours (Experiment 348 or 349). 



