an original technique for fixation , treatment and oriented embedding of the sinoauricular area material of the human heart makes it possible to study ultrastructure of the conducting myocardial in the sinus node ( sn ) and that of the parasinusoid working myocardium in the right atrium ( ra ) , while the spatial interrelations , between the structures of the area examined are fully kept intact .
C0018787
heart
C0225844
right atrium