|
|
Adult head lice are gray, about ? inch long, and often have a tiny dot on their backs. A female can lay between 50 and 150 eggs within the several weeks that she is alive. They feed on human blood.
Interferon was scarce and expensive until 1980, when the interferon gene was inserted into bacteria using recombinant DNA technology, allowing for mass cultivation and purification from bacterial cultures.
Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.
The longest a person has survived after a heart transplant is 24 years.
Drugs are in development that may cure asthma and hay fever once and for all. They target leukotrienes, which are known to cause tightening of the air passages in the lungs and increase mucus productions in nasal passages.