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Asthma is the most common chronic childhood disease in the world. Most children who develop asthma have symptoms before they are 5 years old.
The first oncogene was discovered in 1970 and was termed SRC (pronounced "SARK").
After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
The horizontal fraction bar was introduced by the Arabs.
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