a large immune system cell in the tissues that
devours invading pathogens and other intruders. Macrophages stimulate
other immune cells by presenting them with small pieces of the invaders.
Macrophages also can harbor large quantities of viruses like HIV without
being killed, acting as reservoirs of the virus.
Magnetic Resonance Imaging (MRI) (mag-NEH-tik REH-zuh-nuns
IM-uh-jing)
A test that takes pictures of the soft tissues in
the body. The pictures have advantages over x-rays. Read more
about MRI technology here.
the midpoint value obtained by ranking all values
from highest to lowest and choosing the value in the middle. The median
divides a population into two equal halves.
the part of the brainstem located just above the
spinal cord; means "rather long and narrow;" acting as kind of a
"telephone exchange," the medulla oblongata links the higher brain
centers with several senses.
Megacolon
(MEG-uh-koh-lun)
A huge, swollen colon. Results from severe
constipation. In children, megacolon is more common in boys than girls.
See also Hirschsprung's Disease.
Melena
(muh-LEE-nuh)
Blood in the stool.
Memory cell
memory cells are a subset of T cells and B cells
that have been exposed to specific antigens and can then proliferate
(recognize the antigen and divide) more readily when the immune system
re-encounters the same antigens. (See also
anamestic response.)
Ménétrier's Disease (may-NAY-tree-ayz duh-zeez)
A long-term disorder that causes large, coiled
folds in the stomach. Also called giant hypertrophic gastritis.
Metabolism
(muh-TAH-buh-lih-zum)
The term for the way cells chemically change food
so that it can be used to keep the body alive. It is a two-part process.
One part is called catabolism- when the body uses food for energy. The
other is called anabolism-when the body uses food to build or mend
cells. Insulin is necessary for the metabolism of food.
the transfer of a disease from one part of an
organ to another or to a different organ by the transfer of causative
organisms or, as in the case of cancer, by the transfer of cells.
the gene cluster that controls certain aspects of
the immune response. Among the products of these genes are the
histocompatibility antigens, such as HLA class I antigens, which are
present on every cell with a nucleus and serve as markers to distinguish
self from non-self. (See also HLA
antigens.)
Microbe
A tiny living organism such as bacteria or yeast
that has the potential to trigger chronic illness and disease.
Microwaves
Microwave therapy is a type of deep heat therapy.
The electromagnetic waves pass between electrodes placed on the
patient's skin. This creates heat that increases blood flow and relieves
muscle and joint pain.
Microencapsulated
surrounded by a thin layer of biodegradable
substance referred to as a microsphere. A means of protecting a drug or
vaccine antigen from rapid breakdown. Microencapsulation may also
enhance an antigen’s absorption and the immune response to that antigen.
Migraine
An often familial (occurring in
families) symptom complex of periodic attacks of vascular (pertaining to
blood vessels or indicative of a copious blood supply), headache,
usually temporal (of or pertaining to the temple or temples) and
unilateral (occurring on one side) in onset, commonly associated
with irritability, nausea, vomiting, constipation or diarrhea, and often
photophobia (sensitivity to light), attacks are preceded by constriction
of the cranial arteries (arteries in the head), usually with eye
symptoms and commence with the
vasodilation that follows..
Origin: Gr. Hemikrania = an affection of
half of the head
Chemically and immunologically homogeneous
antibodies produced by a single clone
of antibody-secreting cells; a monoclonal antibody against
glycoprotein IIb/IIIa is
undergoing investigation as a platelet function inhibitor.
Monocyte
a large white blood cell in the blood that
ingests microbes or other cells and foreign particles. When a monocyte
passes out of the bloodstream and enters tissues, it develops into a
macrophage.
Morbidity
Rate
The sickness rate; the number of people who are
sick or have a disease compared with the number who are well.
Mobilization therapies
A group of treatments that include traction,
massage, and manipulation. When used by a trained professional, these
methods can help control pain and increase joint and muscle motion.
Morphology
A study of the configuration the structure of
animals and plants.
Mortality
Rate
The death rate; the number of people who die of a
certain disease compared with the total number of people. Mortality is
most often stated as deaths per 1,000, per 10,000, or per 100,000
persons.
resistance to infection across the mucous
membranes. Mucosal immunity depends on immune cells and antibodies
present in the linings of reproductive tract, gastrointestinal tract and
other moist surfaces of the body exposed to the outside world.
An infarction
caused by obstruction of circulation to a region of the heart; also
called a heart attack; results from permanent damage to an area of the
heart muscle. This happens when the blood supply to the area is
interrupted because of narrowed or blocked blood vessels.
