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Ehrlich ascites tumor cells incubated in vitro with adenine-14C catabolized up to 20% of the radioactive nucleotides which were formed, principally via dephosphorylation of inosinate and xanthylate, with small amounts of adenylate and guanylate broken down. Cells incubated with hypoxanthine-14C catabolized a much larger proportion of nucleotides, principally via dephosphorylation of inosinate and xanthylate; guanylate was also broken down. Catabolic products of guanine-14C in these cells were xanthine, which was formed directly from guanine, and guanosine which at least in part was formed via dephosphorylation of guanylate.

We have used neutron scattering techniques to examine the magnetic transitions in the Ho1-xErxRh4B4 pseudoternary system. A wide variety of behavior is found, ranging from mean-field behavior for HoRh4B4 to complicated behavior for ErRh4B4, where superconductivity and long-range ferromagnetic order coexist between 0.7 and 1.2 K. Long-range ferromagnetic order is found at the lowest temperatures for all alloy compositions. Alloys with more than about 30% Ho order magnetically along the c axis and superconductivity is destroyed in these alloys in a sharp transition coincident with magnetic ordering. Alloys near the ErRh4B4 composition order in the basal plane but undergo a complex ordering process through a sinusoidally modulated state. Because Ho and Er have competing orthogonal magnetic anisotropies, compounds near the composition Ho 0.25Er0.75Rh4B4 are near a multicritical point in the magnetic phase diagram.