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Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
The familiar sounds of your heart are made by the heart's valves as they open and close.
More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.
Approximately 70% of expectant mothers report experiencing some symptoms of morning sickness during the first trimester of pregnancy.
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