EFFECTS OF CERTAIN DRUGS AND POISONS 727 



The calcium content of the serum in tuberculosis was investigated by 

 Halverson, who found that it is not increased by a milk diet. 



Magnesium, as shown by Malcolm, lessens lime deposition in young 

 animals. In accord with this fact Mendel and Benedict found that it in- 

 creases the urinary calcium. The presence of phosphates, however, in- 

 hibits the increase by magnesium of calcium excretion in the urine (Steen- 

 bock and Hart). 



Strontium administration to young animals disturbs bone formation. 

 Lehnerdt showed that the osteogenetic tissue is stimulated, but the bones 

 become imperfectly calcified, the calcium being deficient and the strontium 

 incompletely deposited. 



In the magnesium narcosis of Meltzer and Auer (which can be an- 

 tagonized by calcium chlorid injections) Stronsky has studied the plasma 

 and has shown an increase in the magnesium content while the calcium 

 content is diminished. 



C. Mayer maintains that the chlorids of the alkaline earths tend to 

 increase urinary acidity. This is contradictory to the usual holding since 

 part of the phosphate is deflected by calcium, for example, to the intestines. 



Calcium Deprivation. In young animals fed on a calcium-poor diet 

 the bones may contain a normal percentage of calcium, but what little new 

 bone is formed is thin, pliable, deformed and fragile (E. Voit). It con- 

 tains more water, sodium and potassium, while the magnesium is not 

 materially increased. The percentages vary in different parts of the 

 skeleton. Weiser describes the animals as undersized, with poor appetite 

 and defective nutrition. Luithlen has increased or decreased the calcium 

 content of the bones in rabbits by feeding, respectively, a green or an oat 

 diet. (See also Oxalates.) 



In studies of multiple exostosis Underbill, Honeij, and Bogert found 

 evidence suggesting that a restriction of the calcium and magnesium in- 

 take during the stage of proliferative cartilage changes would be bene- 

 ficial. 



Calcium in Diseases of Bone Deficiency. Rickets, being due not to 

 deficient calcium income, but to derangement of the processes of assimila- 

 tion, the therapeutic inefficiency of calcium in this disease has been gen- 

 erally upheld (Klotz(fc)). This does not mean, however, that none of the 

 administered calcium is retained. Schloss(&), for example, reports in a 

 series of eighty experiments upon rachitic children the following results: 



Retention of CaO 

 gram per day. 



Fore period 0.032 



With calcium administration 0.297 



With cod liver oil . 0.167 



With cod liver oil and calcium. 0.354 '"['.*' "\ 



