Complement fixation inhibiting and complement-fixing antibodies were demonstrated in sera from cats during the acute and convalescent stages, respectively, of feline picornavirus infections. Complement-fixing antibody activity was present in 19S and 7S globulins, whereas complement fixation inhibiting antibody activity was confined to the 7S globulins. Sera with complement-fixing antibody and s...

Analysis of the sera from both R.A. and the control group on a Technicon SMA 12/60 revealed no abnormality of liver or kidney function which might have suggested difference in immunoglobulin metabolism. The Gm phenotype distributions were also similar, indicating that the Gm groupings were not associated with the coniigurational differences observed. Several workers have commented on the stabil...

Electron micrographs of isolated human alpha(2)M-molecules, obtained by the negative contrast technique, revealed morphologically homogenous structures resembling a graceful monogram of the two letters H and I. The modal values for the length and width of the alpha(2)M particles were 170 A and 100 A, respectively. Purified rabbit alphamacroglobulins contained about 80% alpha(1)M- and 20% alpha(...

Experimental evidence is presented that the intrinsic viscosity of solutions of mixed proteins obeys the additive equation See PDF for Equation. The datum serves to characterize the system, and combined with other analytical techniques and fractionation procedures, enables one to analyze and characterize subfractions. The plasmas and sera of clinically "normal" individuals give intrinsic viscos...