|
|
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.
Hippocrates noted that blood separates into four differently colored liquids when removed from the body and examined: a pure red liquid mixed with white liquid material with a yellow-colored froth at the top and a black substance that settles underneath; he named these the four humors (for blood, phlegm, yellow bile, and black bile).
There are 60,000 miles of blood vessels in every adult human.
After 5 years of being diagnosed with rheumatoid arthritis, one every three patients will no longer be able to work.
In 1864, the first barbiturate (barbituric acid) was synthesized.