(thÃ»r'mÄ«'Én) An electrically charged particle or ion that is emitted by a heated conducting material. The electrons emitted from the cathodes of electron tubes (such as cathode ray tubes) are thermions.
A low white blood cell count (leukopenia) is a decrease in disease-fighting cells (leukocytes) in your blood. Leukopenia is almost always related to a decrease in a certain type of white blood cell (neutrophil). The definition of low white blood cell count varies from one medical practice to another. In general, for adults a count lower than 4,000 white blood cells per microliter of blood is considered a low white blood cell count. For children, that threshold varies with age.
A normal white blood cell count should be between 4,000 and 11,000 leukocytes, any amount lower than that margin indicates a decline that needs to be addressed. The first step is to determine why the white blood cell count is low, a bacterial infection, a virus or conditions such as anaemia are often responsible, but there are other conditions that can lead to this condition. In our article what are the causes of a low white blood cell count you can discover all the diseases that lead to this condition.