Abstract
On the assumption that gelation in sero xelo-gel figure would be influenced by pH at the time of the reaction, acid and alkali were added to serum to observe their effect on the figure, and the following results were obtained.
1) Sero-xelo-gel figure of serum from normal healthy persons turned positive the more perfectly the further its pH was elevated above the neutral point by adding alkali, until at last it became type IX.
2) Serum which was turned positive by adding alkali again became negative when acid was added to it, thus demonstrating reversibility of the reaction.
3) When acid was added to tumor-positive serum, transition of the figure toward negativity was observed. However, perfect type IX tumor serum did not give such transition in some cases
4) Statistically, no correlation was observed between the reaction type and pH of serum from normal healthy subjects and pregnant women, but the correlation was positive in a medium degree for tumor serum.
