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INTERNAL SECRETION 



lieved that his experiments pointed to a lesion of the anterior 

 portion of the restiform body as the originating factor of Graves's 

 disease, but that the symptoms are manifested by the agency of 

 the thyroid gland. The later attempts to prove the neurogenic 

 origin of the disease were based upon a more complete knowledge 

 of the innervation of the thyroid gland. Experiments to this end 

 were undertaken by Briau at Morat's laboratory and they show 

 that the sympathetic nerve of the neck contains fibres which act 

 as vaso-dilators to the blood-vessels of the thyroid. Wiener has 

 recently expressed the view, based upon his discoveries concerning 

 the innervation of the thyroid, that the thyroid derangement is not 

 the primary feature of Graves's disease, but is a secondary con- 

 dition brought about by abnormal innervation of the gland. 



Whether the thyroid affection is primary or is a secondary 

 feature of nervous origin, one thing is universally conceded, and 

 that is, that the thyroid gland is the pathogenetic centre from 

 which the symptom-complex of Graves's disease proceeds. A 

 rational explanation of the condition is offered by the assumption 

 of a functional anomaly on the part of the thyroid gland. The 

 grounds for this assumption are as follows : (i) The invariable 

 occurrence of a pathological enlargement of the gland the 

 anatomically and histologically characteristic goitre ; (2) the 

 coincidence of the first clinical symptoms with the swelling of the 

 gland, especially as seen in those instructive cases (acute inflamma- 

 tion, syphilitic changes, metastases of neoplasms) where the 

 sudden affection of the gland is attended by the immediate appear- 

 ance of the clinical signs; and (3) the remarkable therapeutic 

 results by which partial extirpation is invariably attended. 



The thyrogenic theory of the origin of Graves's disease 

 receives remarkable support from the antagonism, described by 

 Moebius, between the clinical symptoms of athyrosis as manifested 

 in myxcedema and in Graves's disease. This is well seen in 

 A. Kocher's comparison of the symptomology of Graves's disease 

 with that of cachexia thyropriva. 



CACHEXIA THYROPRIVA. 



Absence or atrophy of the 

 thyroid gland. 



Slow, small, regular pulse. 



Absence of vascular congestion 

 and coldness of the skin. 



Indifferent expression, lacking 

 in movement and vitality. 



Narrowed eyelids. 



GRAVES'S DISEASE. 



Swelling, generally diffuse, of 



the thyroid gland, hyper- 



vascularization. 

 Rapid, frequently tense, jerky, 



occasionally irregular pulse. 

 Extreme excitability of the 



vascular nerves. 

 Anxious, roving glance which 



appears angry when fixed. 

 Wide open eyelids, exophthal- 



mos. 



