Abstract: An antiviral agent comprising 1-.beta.-D-arabinofuranosylthymine as a therapeutically efficacious component in a pharmaceutical form for absorption through the alimentary canal of the human or lower animal to be treated.

Abstract: S-adenosyl-L-methionine compositions stabilized against decomposition of S-adenosyl-L-methionine comprising S-adenosyl-L-methionine, a sulfuric acid equivalent and a nucleoside sulfate, which are produced from a solution comprising the three essential components in an aqueous solvent by, for example, adding thereto a water-miscible organic solvent thereby to precipitate the composition (process A) and/or by evaporating the aqueous solvent off the solution (process B).

Abstract: A new composition of matter, 1-.beta.-D-arabinofuranosylcytosine-5'-oleyl phosphate, represented by the structural formula ##STR1## and its pharmaceutically-acceptable salts exhibit antitumor properties and are especially useful for oral administration thereof.

Abstract: An L-lysine .alpha.-oxidase, that is, a novel L-amino acid oxidase having very high substrate-specificity to L-lysine is produced by culturing a specific microorganism belonging to Trichoderma in a medium.

Abstract: L-lysine contained in a sample can be efficiently determined by using the L-lysine .alpha.-oxidase. The preferred enzyme is an L-lysine .alpha.-oxidase, that is, a novel L-amino acid oxidase having very high substrate-specificity to L-lysine is produced by culturing a specific microorganism belonging to Trichoderma in a medium.

Abstract: A stabilized dry S-adenosyl-L-methionine preparation is obtained by incorporating about 1 - 10 parts by weight of lithium in the form of a salt with 100 parts by weight of S-adenosyl-L-methionine or a low-toxicity salt thereof. According to the invention, instability of S-adenosyl-L-methionine or a salt thereof is substantially eliminated. The stabilized dry preparation is very useful as medical drugs and reagents for biochemical research.

Abstract: N.sup.2,2'-O-dibutyrylguanosine-3',5'-cyclic phosphate or a salt thereof is stabilized by adjusting the moisture content thereof to 3 percent or less by weight.

Abstract: Crystalline N.sup.6,2'-O-dibutyryl-adenosine-3',5'-cyclic monophosphate monosodium salt (DB.sub.c -AMP-N.sub.a), and a process for producing the same which may comprise the step of causing at least one solvent selected from an ether, ketone, and an ester, constituting a crystallizing organic solvent, to contact an alcoholic solution, aqueous alcoholic solution, or a simple aqueous solution of DB.sub.c -AMP-N.sub.a or may comprise the step of dissolving crude crystalline or amorphous DB.sub.c -AMP-N.sub.a in a mixture of an alcoholic solvent and the crystallizing organic solvent.

Abstract: The enzyme pterin deaminase may be used as an antitumor agent, and can be produced from cultures of the fungal genera Aspergillus, Mucor, Rhizopus, and Penicillium.