португальский
nó sinusal 
A specialized bit of heart tissue that controls the heartbeat.
1
The results were used to refine the Noble-DiFrancesco-Denyer model of spontaneous pacemaker activity of the SA node.
2
PMID: 1283636 The results were used to refine the Noble-DiFrancesco-Denyer model of spontaneous pacemaker activity of the SA node.