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In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Multiple experimental evidences have confirmed that at the molecular level, cancer is caused by lesions in cellular DNA.
The U.S. Preventive Services Task Force recommends that all women age 65 years of age or older should be screened with bone densitometry.
The horizontal fraction bar was introduced by the Arabs.
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