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There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
The first oncogene was discovered in 1970 and was termed SRC (pronounced "SARK").
Most women experience menopause in their 50s. However, in 1994, an Italian woman gave birth to a baby boy when she was 61 years old.
This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
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