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More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
Multiple experimental evidences have confirmed that at the molecular level, cancer is caused by lesions in cellular DNA.
Vaccines prevent between 2.5 and 4 million deaths every year.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
The human body produces and destroys 15 million blood cells every second.
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