CSF (cerebrospinal fluid): A watery fluid, continuously produced and absorbed, which flows in the ventricles (cavities) within the brain and around the surface of the brain and spinal cord.
The CSF is produced by the choroid plexus, a series of infolded blood vessels projecting into the cerebral ventricles, and it is absorbed into the venous system.
If production exceedes absorption, the CSF pressure rises and the result is hydrocephalus. This can also occur if the CSF pathways are obstructed and CSF accumulates.
CXCR4: A chemokine receptor found on a wide variety of cells that serves as the coreceptor for HIV. HIV strains that use CXCR4 are referred to as X4 viruses.
Cyanide: Poisoning with cyanide, a rapidly acting, potentially deadly chemical that can exist as a colorless gas, such as hydrogen cyanide (HCN) or cyanogen chloride (CNCl), or a crystal form such as sodium cyanide (NaCN) or potassium cyanide (KCN). Cyanide sometimes is described as having a “bitter almond” smell, but it does not always give […]
Cyanosis: A bluish color of the skin and the mucous membranes due to insufficient oxygen in the blood. For example, the lips can develop cynanosis when exposed to extreme cold. Cyanosis can be present at birth, as in a ‘blue baby,’ an infant with a malformation of the heart that permits into the arterial system […]
Cyanotic: Showing cyanosis (bluish discoloration of the skin and mucous membranes due to not enough oxygen in the blood). See: Cyanosis.
- Cycle, cell
Cycle, cell: The sequence of events within the cell between mitotic (cell) divisions. The cell cycle is conventionally divided into five phases: G0 (the gap); G1, (the first gap); S (the synthesis phase, during which the DNA is synthesized and replicated); G2 (the second gap); and M (mitosis). Cells that are not destined to divide […]