38 



Dr. J. Rose Bradford. 



[Mar. 3, 



Kjeldahl determinations should nearly coincide, whereas, if such a 

 body as creatin, &c, is present, the one method would yield twice as 

 much nitrogen as the other. In the present communication only 

 the extractives present in what has been called above the " absolute 

 extract " will be considered, and the results obtained in four experi- 

 ments are given below. In two cases, No. 19 and No. 21, the removal 

 of two-thirds of the kidney weight had produced simple hydruria, 

 and in the other two cases, No. 23 and No. 28, a more extensive 

 operation had produced polyuria as well. In 23, the polyuria was 

 absolute, in 28 relative, the ingesta being diminished in the latter but 

 not in the former. 



It is to be distinctly understood that in the following results the 

 extractive is reckoned on urea, because of its solubility in cold alsolute 

 alcohol, and because the amount of nitrogen obtained by the Dupre 

 and Kjeldahl methods respectively practically coincided. 





Blood. 



Muscle. 



Liver. 



Brain. 



No. 19 



No. 21 



No. 23 



No. 28 



0-065 p.c. 

 0-045 „ 

 0-410 „ 

 0-360 „ 



-030 p.c. 

 0-035 „ 

 0-430 „ 

 0-300 „ 



nil 

 -024 p.c. 

 0-200 „ 

 0-200 „ 



0-04 p.c. 

 0-03 „ 

 0-24 „ 

 22 „ 



No. 23 was passing an average of 21 grams of urea per diem at the 

 time of death, and No. 28 an average of 8 grams, although in the 

 latter case 10' 6 grams of urea were excreted in the last twenty-four 

 hours of life. From these results we see that in the case of dogs 

 suffering from the simple hydruria, the amount of £k urea " in the blood 

 and tissues is only slightly above the normal. In the case of the dogs 

 in the second stage, suif ering from polyuria, &c, the amount of " urea " 

 in the blood and tissues is enormously increased. Thus, in No. 23 at 

 least twenty times the normal quantity of " urea " was present in the 

 blood, at a time when the animal was still excreting an amount 

 greatly exceeding the normal (vide Table II). Hence the excess of 

 extractive matter present in the tissues is not dependent on simple 

 retention, but on increased production. 



I trust to consider the extractives soluble in rectified alcohol in a 

 future communication, but they also are largely increased in the 

 tissues, but not in the blood. 



The specific gravity of the blood serum is lower than normal, 

 sinking frequently to 1025. The total solids, the proteids, and the 

 ash of the serum are all diminished in amount, the last falling to 

 0'5 per cent, in many cases. 



The disturbance of nutrition with increased production of urea 



