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The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
The first documented use of surgical anesthesia in the United States was in Connecticut in 1844.
There are approximately 3 million unintended pregnancies in the United States each year.
Women are 50% to 75% more likely than men to experience an adverse drug reaction.
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