Just a 10 percent shift in the salt concentration of your blood would make you very sick. To keep that from happening, the body has developed a finely tuned physiological circuit that includes information about that and a beverage's saltiness, to know when to signal thirst.
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A female adult head louse clings to a hair plucked from a human scalp. The brown line visible inside the insect, on the left side of its body, is its last blood meal. Lice typically eat a few times a day.
After a sports injury, Esteban Serrano owed $829.41 for a knee brace purchased with insurance through his doctor's office. He says he found the same kind of brace selling for less than $250 online.
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For people with a rare condition known as misophonia, certain sounds like slurping, chewing, tapping and clicking can elicit intense feelings of rage or panic.
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A study found that consuming two eggs per day was linked to a 27 percent higher risk of developing heart disease. But many experts say this new finding is no justification to drop eggs from your diet.