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Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
In 1864, the first barbiturate (barbituric acid) was synthesized.
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
For about 100 years, scientists thought that peptic ulcers were caused by stress, spicy food, and alcohol. Later, researchers added stomach acid to the list of causes and began treating ulcers with antacids. Now it is known that peptic ulcers are predominantly caused by Helicobacter pylori, a spiral-shaped bacterium that normally exist in the stomach.
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