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There are more sensory neurons in the tongue than in any other part of the body.
Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.
Thyroid conditions cause a higher risk of fibromyalgia and chronic fatigue syndrome.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
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