Ask unlimited questions for free
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
Medication errors are three times higher among children and infants than with adults.
Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
For a complete list of videos, visit our video library