Abstract
Endemic goitre has been spreading over the area including Jehol and its vicinity, Manchoukuo, and North China beyond the Great Wall. Prof. Takamori and members of his clinic have made dozens of expeditions in various parts of Jehol and its vicinity.
Previous investigations by our department found that it was most prevalent along the boundary of the Great Wall, in some parts of which its incidence was over 85 %.
It was proved by Ito of our department, that in about 78 % of the patients the functions of the thyroid gland were almost normal and might be classed as euthyroidism ; the rest showed hyperthyroidism or hypothyroidism. Moreover, endemic cretinism, myxedema, and idiocy, etc. were found in areas of high endemicity.
Recently, Takei, of our department, determined the amount of iodine in the food produced in that district, and found that its content is much less than it is in those produced in Hokkaido, Japan, but is almost equivalent to that of American products. Moreover, he proved that the iodine content of the food produced in the endemic area is lower than in the nonprevalent districts. Ito's researches with regard to iodine metabolism show that the iodine intake of the residents in goitrous districts (JJehol) is less than that of those in nongoitcous districts.
I have collected 150 samples of soil from various parts of Manchoukuo and the northern parts or North China, in order to ascertain whether any relation exists betWen the amount of iodine in the soil and the incidence of goitre.
