Myelosuppression - a decrease in the production of blood cells, which may lead to low blood count. Pancytopenia - a lowering of all three types of blood cells; red blood cells, platelets, and white blood cells, which may lead to low red blood cell count, low blood platlet count, and/or low white blood cell count.
Helium is used as a cooling medium for the Large Hadron Collider (LHC), and the superconducting magnets in MRI scanners and NMR spectrometers. It is also used to keep satellite instruments cool and was used to cool the liquid oxygen and hydrogen that powered the Apollo space vehicles.
Because liquid nitrogen instantly freezes anything on contact, dermatologists can use it to simply dry out unwanted tissue and let it fall off. Surgeons also use cryotherapies to eliminate cancerous cells. In the kitchen, liquid nitrogen is used to make ice cream, flash-freeze herbs or freeze alcohol. Bartenders will swirl it around glasses to chill them, so that the supercooled glass will emanate a dramatic-looking vapor. (Liquid nitrogen creates a fog when exposed to air.)