|
|
Intradermal injections are somewhat difficult to correctly administer because the skin layers are so thin that it is easy to accidentally punch through to the deeper subcutaneous layer.
In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.
There are 20 feet of blood vessels in each square inch of human skin.
Your skin wrinkles if you stay in the bathtub a long time because the outermost layer of skin (which consists of dead keratin) swells when it absorbs water. It is tightly attached to the skin below it, so it compensates for the increased area by wrinkling. This happens to the hands and feet because they have the thickest layer of dead keratin cells.
In 1886, William Bates reported on the discovery of a substance produced by the adrenal gland that turned out to be epinephrine (adrenaline). In 1904, this drug was first artificially synthesized by Friedrich Stolz.