Arrayed library: In genetics, an arrayed library consists of (in technical terms) individual primary recombinant clones which are hosted in phage, cosmid, YAC, or another vector that have been placed in two- dimensional arrays in microtiter dishes (plastic dishes with an orderly array of tiny wells). Each primary clone can be identified by the identity of the plate and the clone location (row and column) on that plate. Arrayed libraries of clones are used for many purposes, including screening for a specific gene or genomic region. The information gathered on individual clones from genetic linkage and physical map studies is then entered into a database and used to construct physical and genetic linkage maps
- Arrectores pilorum
Arrectores pilorum: Tiny muscles that act as the hair erector muscles. The arrectores pilorum play a key role in goose bumps, a temporary local change in the skin The chain of events leading to this skin change starts with a stimulus such as cold or fear. That stimulus causes a nerve discharge from the sympathetic […]
Arrhythmia: An abnormal heart rhythm. In an arrhythmia the heartbeats may be too slow, too rapid, too irregular, or too early. Rapid arrhythmias (greater than 100 beats per minute) are called tachycardias. Slow arrhythmias (slower than 60 beats per minute) are called bradycardias. Irregular heart rhythms are called fibrillations (as in atrial fibrillation and ventricular […]
- Arrhythmia, sinus
Arrhythmia, sinus: The normal increase in heart rate that occurs during inspiration (when you breathe in). This is a natural response and is more accentuated in children than adults. The “sinus” refers to the natural pacemaker of the heart which is called the sinoatrial (or sinus) node. It is located in the wall of the […]
- Arrhythmias, atrial
Arrhythmias, atrial: Abnormal heart rhythm due to electrical disturbances in the atria (the upper chambers of the heart) or the AV node “relay station”, leading to fast heart beats. Examples of atrial arrhythmias includes atrial fibrillation, atrial flutter, and paroxysmal atrial tachycardia (PAT).
- Arrhythmias, rapid
Arrhythmias, rapid: Abnormally rapid heart rhythms, medically termed tachycardia.