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Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
It is difficult to obtain enough calcium without consuming milk or other dairy foods.
The first documented use of surgical anesthesia in the United States was in Connecticut in 1844.
The horizontal fraction bar was introduced by the Arabs.
After 5 years of being diagnosed with rheumatoid arthritis, one every three patients will no longer be able to work.
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