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The horizontal fraction bar was introduced by the Arabs.

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Essential fatty acids have been shown to be effective against ulcers, asthma, dental cavities, and skin disorders such as acne.

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Many of the drugs used by neuroscientists are derived from toxic plants and venomous animals (such as snakes, spiders, snails, and puffer fish).

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The familiar sounds of your heart are made by the heart's valves as they open and close.

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Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.

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