What exactly is a heart attack? Most heart attacks happen when a clot in the coronary artery blocks the supply of blood and oxygen to the heart. Often this leads to an irregular heartbeat-called an arrhythmia-that causes a severe decrease in the pumping function of the heart.
Oncocytoma can be described as a tumor that is mainly constituted out of oncocytes. These are actually epithelial cells, containing excessive quantities of mitochondria. This excess leads to a cytoplasm that is acidophilic and granular.
Astrocytomas are primary intracranial tumors derived from astrocytes cells of the brain. It is also possible that glial progenitors or neural stem cells give rise to astrocytomas. Astrocytomas are brain tumors that develop from astrocytes. They may occur in many parts of the brain and sometimes in the spinal cord.