Category: M

A source of microwave energy used in medical linear accelerators to accelerate electrons to therapeutic energies.  

The magnetic polarization of a material produced by a magnetic field (magnetic moment per unit volume).  

A measure of the ability of a substance to become magnetized.  

A measure of the net magnetic field produced by an elementary particle or an atomic nucleus spinning about its own axis. These fields are similar to those produced by a bar magnet.  

Injury caused by a marine animal. Marine stings can be very painful and quite toxic. Marine animals known to sting include the jellyfish, sea anemone, Portuguese man-of-war, stingray, sea urchin, and spiny fish, some of which, even after they are dead, can inject venom through their tentacles into the skin of swimmers. Marine stings can…

The group of organs involved in a man’s capacity to produce sperm (male reproductive cells), have sexual intercourse, and fertilize an egg (female reproductive cell) to produce offspring. The male reproductive components, involved in both sperm production and sexual intercourse, encompass the testes (see testis), where sperm and male sex hormones (also known as androgen…

Excessive consumption of prescription or nonprescription medications, either by accident or deliberately. An overdose can involve seemingly harmless drugs sold over the counter such as aspirin, acetaminophen, iron, vitamins, antihistamines, and sleep aids which in large enough doses can be fatal. Children and older people are at particular risk for medication overdose, but any person…

A group of related, progressive disorders of the bone marrow characterized by low populations of abnormally developed blood cells. Since myelodysplastic syndrome precedes the development of acute leukemia in approximately one case in four, it is sometimes called preleukemia. The current understanding of this disease is that all blood cells (white, red, and platelets) develop…

Another name for a rare dissociative identity disorder, an emotional condition in which a person has two or more distinct identities that surface regularly, control the person’s actions, and know little about the other identities; the identities are in conflict with one another. Multiple personality is considered a dissociative disorder because the individual becomes detached,…

A syndrome in which a person reports multiple symptoms that he or she believes are due to low-level chemical exposure and that interfere with daily life and work. People with this condition often report symptoms after they have been exposed to an environmental chemical, such as a pesticide or chemical used in a building remodeling.…