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Nearly 31 million adults in America have a total cholesterol level that is more than 240 mg per dL.
The familiar sounds of your heart are made by the heart's valves as they open and close.
Approximately 70% of expectant mothers report experiencing some symptoms of morning sickness during the first trimester of pregnancy.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.
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