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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.
About 600,000 particles of skin are shed every hour by each human. If you live to age 70 years, you have shed 105 pounds of dead skin.
Colchicine is a highly poisonous alkaloid originally extracted from a type of saffron plant that is used mainly to treat gout.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
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