Effects of soyabean and ascorbic acid on experimental carcinogenesis.

1. Ultrastructural changes in liver tissue of mice fed nitrosamine precursors, dibutylamine and nitrite, were observed. 2. The protective effect of soyabean in a diet containing nitrosamine precursors was demonstrated. 3. Liver tissue was examined to investigate the anticarcinogenicity of ascorbic acid. 4. The significance of soyabean and ascrobic acid in counteracting the potential hazards due to nitrosamine precursors is discussed.