Ключевые слова: blood, cardiac, cardiology, care, checkup, clinic, clinical, closeup, coronavirus, device, electronic, electronics, equipment, face mask, facial mask, finger, fingertip, hand, health, healthcare, heartbeat, hospital, level, mask, measurement, medic, medical, medicine, monitoring, nobody, oximeter, oximetry, oxygen, oxygen saturation, oxygenation, oxymeter, pneumonia, portable, ppe, protection, protective, pulse, pulse oximeter, pulsoximeter, rate, respiratory, saturation, stethoscope, test,