Columbia subject headings:
Blood--Diseases--United States--Periodicals.
Cardiovascular system--Diseases--United States--Periodicals.
Lungs--Diseases--United States--Periodicals.
National Heart, Lung, and Blood Institute--Periodicals.
Harvard subject headings:
Blood--Diseases--United States--Periodicals.
Cardiovascular system--Diseases--United States--Periodicals.
Lungs--Diseases--United States--Periodicals.
National Heart, Lung, and Blood Institute--Periodicals.
Princeton subject headings: