Hairy cell leukemia (HCL) 1  Is a type of blood cancer that begins in the bone marrow. 2  Is a rare type of leukemia in adults.  Hairy cell leukemia gets its name from the short, thin projections that look like hair on its cells.
In 1799 Humphrey Davy discovered anesthetic properties of nitrous oxide (N20)---also known as laughing gas.. He had recently joined Thomas Beddoesâ Pneumatic Institution (established 1798) for treatment of disease by inhalation.
The word anesthetic traces back to the Greek word anaisthÄsia, from a combination of an-, meaning âwithoutâ and aisthÄsis, meaning âsensation.â If you take an anesthetic thatâs what happens: you are temporarily without sensation, meaning you feel no pain. A general anesthetic causes temporary unconsciousness and is often used during surgeries.