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On average, someone in the United States has a stroke about every 40 seconds. This is about 795,000 people per year.
People with high total cholesterol have about two times the risk for heart disease as people with ideal levels.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
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