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The most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.
The longest a person has survived after a heart transplant is 24 years.
In 1864, the first barbiturate (barbituric acid) was synthesized.
The human body produces and destroys 15 million blood cells every second.
After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
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