28 PHYSIOLOGY CHAP. 



These experiments have recently been confirmed by Christian! 

 (1901) on a large number of animals. 



He gives certain important details in regard to the method of 

 performing the thyroid grafb so that it shall take well. 



No arbitrary quantity of thyroid can be grafted, but only such 

 an amount as is required by the body in each individual case. If, 

 e.g., a whole thyroid is grafted on a completely dethyroidised rat, it 

 may become attached as a whole, but if a whole thyroid, or several 

 thyroids, are grafted] on a partially dethyroidised rat, a part only 

 takes root, corresponding, to a certain degree, with the deficit. 



This shows that the action of the thyroid is, generally speaking, 

 more useful to the body in proportion as the maximal intensity of 

 its function is contained within physiological limits. 



Graves' or Basedow's disease, which is characterised by a 

 well-known complex of symptoms (tachycardia, oesophthalmia, 

 increase of general katabolic processes, etc.) is now attributed by 

 the majority of clinicians to exaggerated activity of the thyroid, 

 whatever the conditions which initiated it. The same syndrome 

 is also exhibited when thyroid preparations are administered to 

 persons whose thyroid is normal, as, e.g., with the therapeutic object 

 of reducing obesity. 



However efficacious in this direction, the cure is so dangerous 

 owing to its tendency to produce the symptoms of Graves' disease, 

 that it has now been generally abandoned (Striimpell). 



Eiselsberg, having failed with other clinicians in the radical 

 cure of spontaneous or operative myxoedema by thyroid grafting, 

 owing to the difficulty of regeneration, put in practice Schiffs 

 suggestion by preparing a thyroid extract, and injecting it beneath 

 the skin of dethyroidised animals. His results, however, were not 

 encouraging, either from the position of the injection, or from the 

 amount of juice injected. Vassale was more fortunate. At the 

 end of 1890, independent of Eiselsberg, seeing the therapeutic 

 efficacy of certain drugs injected directly into the veins (Baccelli), 

 he injected large quantities of thyroid juice into dethyroidised 

 dogs, and obtained a beneficial, though transitory, action from such 

 injections. These results were amply confirmed by Gley (1891), 

 and applied very successfully by Murray (1893), both in a case 

 of spontaneous myxoedema and in a monkey deprived of its 

 thyroids. 



A year after Murray's first cure of myxoedema Howitz, 

 Mackenzie, and Fox substituted the administration of thyroid by 

 the mouth for venous injections. This method is very simple, and 

 within the grasp of all ; and it gives surprising therapeutic 

 results in cases of myxoedema which have gone on for years, and 

 proved refractory to all kinds of treatment. This shows that the 

 active principles of the thyroid juices are not decomposed by the 

 action of the digestive secretions. 



