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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.
This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
Essential fatty acids have been shown to be effective against ulcers, asthma, dental cavities, and skin disorders such as acne.
About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.
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