Direct-acting vasodilators that are smooth muscle relaxants include which of the following medications?
I. Nitroglycerin
II. Furosemide
III. Nitroprusside

The two specialized cell types contained within the sinoatrial (SA) node:

Which of the following is NOT a measurement on an arterial blood gas (ABG) analysis?

Atrial septal defects allow blood to be shunted between the left and right atria. The most common atrial septal defect is: