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Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
About 100 new prescription or over-the-counter drugs come into the U.S. market every year.
Multiple experimental evidences have confirmed that at the molecular level, cancer is caused by lesions in cellular DNA.
The horizontal fraction bar was introduced by the Arabs.
Human kidneys will clean about 1 million gallons of blood in an average lifetime.
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