3..0Use of Iodine 131 a of monotodoryrosias let of thyroid cxtract. ee millionths of e gram} & éded to the original drop= Some cf tha otners eve in approximately the piszd by compounds similar to positions which one mipht expset to be crcup 4o thyrozine but conteining one, two or thre2 icline etoms, It would ap= pear then, that a relatively | simple new t2chrique has onened the way to a mosh ecetailed study of the steps by whith tue thyroid hormone is The Sere teachuiaus has been used in a proliminary fashion for 6 ° the adstops } : in the formetion of evzer vrom redioective carbon di- ae . akécwn of the M cr Hi tr oO ~ih QO i) re & u hr ae dy +) ts ™ sq cr c dp] rd te a ° tor Q bt ¢ tar OQ Ne swoS eee irs] tedy ofP io ct fr ) i 1 \ i) O 2 fT © ornide in plents (phetosynthesic), and a .inilaur presedure hes been used s nt +t, Fw? aoa op ~ a~# y at an oe emino ecid witch hia et tered Csetvetion by convene “ @hlesely ellied proceedure thieh eppssra to shew promise employs cftocctive reasents, sether then color reacents, for cetecting the preL1aes oP noneradloactive compounds in the filter psper chrometorren. = Pevelopnent of such a prosedure, by makirne rossible the ¢etection or even the scourats determination of substrnecs prasent in fantastically low concentraticas in urine, blood or otl/.er “luids, might well lead to polica tious in clinical diagnosis.