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Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Vaccines prevent between 2.5 and 4 million deaths every year.
The word drug comes from the Dutch word droog (meaning "dry"). For centuries, most drugs came from dried plants, hence the name.
There are more nerve cells in one human brain than there are stars in the Milky Way.
In 1864, the first barbiturate (barbituric acid) was synthesized.
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