To examine the universal validity of results in preceding reports on hepatitis B antigen among inhabitants of Yachiho village, 4015 farmers in Nagano were investigated. Hepatitis B antigen were detected for 24 persons with single radial immunodiffusion method. The incidence of 0.6 per cent with the insensitive method was compatible with 1.3 per cent in the village with immune adherence hemagglutination method. The prefecture was devided into four areas. The areas where hepatitis B antigen was prevalent persons with elevated transaminase value were frequent.

Topical cardiac hypothermia has unequivocal preservation effects during ischemia, but it has some disadvantages. Topical cooling, especially with ice slush, can injure the phrenic nerve, disturb the equal distribution of the cardioplegic solution due to coronary artery spasm and damage the epicardium. It is easy to prevent cooling injury without topical hypothermia, but the myocardial oxygen demands are increased. In order to supply the myocardium with oxygen for the increased oxygen demands during ischemia, isolated rat hearts were immersed in perfluorochemicals (PFC) which have excellent transportation of oxygen. The effects of immersion in PFC during mild hypothermic ischemia (at 20°C without cardioplegia and at 30°C cardioplegic arrest) on the cardiac function on reperfusion were evaluated. Under 20°C hypothermic ischemia without cardioplegia, cardiac beating was maintained for 20±4 minutes in the hearts were immersed in PFC, and for 10±2 minutes in the hearts that were not immersed in any solution. In the recovery of cardiac function (LVDP and LV_max dp/dt) after mild hypothermic (30°C) cardioplegic arrest, the hearts immersed in PFC showed better results than hearts that were not immersed.