BIOLOGY IN HUMAN AFFAIRS 



injured in pre-natal life and that subsequent provision of 

 iodine will not prevent some abnormality in the gland. 

 The importance of keeping the expectant mother's thyroid 

 provided with iodine is, therefore, apparent. 



Secondary Anemia and Iron Assimilation. Secondary anemia 

 may be due to excessive hemorrhage, hookworm, chemical 

 poisoning, etc. The impoverished blood tends to return 

 promptly to normal when an adequate diet is provided. 

 An interesting discovery made by Hart and co-workers 

 relates to the conditions under which iron can be assimi- 

 lated and converted into the respiratory pigment of the 

 red blood corpuscles. They have shown that iron assimi- 

 lation is impossible in the absence of a small quota of 

 copper in the body. When the diet is entirely adequate in 

 every respect, including copper, inorganic iron salts are 

 capable of utilization for hematin synthesis. The relative 

 values of iron salts depend only upon their solubility; 

 although it was demonstrated some years ago that, if 

 ferrous salts are introduced into the food, oxidation of 

 vitamin A by the air is strongly catalyzed. For this reason 

 animals may be fed an adequate amount of A, but if the 

 iron is in the ferrous form, the vitamin A may be destroyed 

 and the animals will then develop the typical ophthalmia 

 of dietary origin. 



Until recently, pernicious anemia did not yield to any 

 form of treatment. Minot and Murphy discovered that 

 when pernicious anemia patients are given large amounts 

 of liver daily, the blood stream promptly improves and the 

 anemia disappears in great measure. The disease is not 

 curable; and liver, or a suitable preparation from it, must 

 be taken throughout life, otherwise a return of the anemia 

 is certain. 



All pernicious anemia patients have a long history of 

 digestive disturbances terminating in a loss of capacity 

 of the stomach to produce hydrochloric acid. It has been 



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