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Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.
In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
There are more bacteria in your mouth than there are people in the world.
People with high total cholesterol have about two times the risk for heart disease as people with ideal levels.
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