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When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
The most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.
The average adult has about 21 square feet of skin.
There are more bacteria in your mouth than there are people in the world.
This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.
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