MOLE
MONONUCLEOSIS, INFECTIOUS
uterus (an invasive mole). A molar preg-
nancy that becomes cancerous is called
a
choriocarcinoma.
If the dead embryo and placenta are
not expelled from the uterus after a
mis-
carriage,
the dead tissue is called a
carneous mole.
mole
A type of pigmented
naevus.
(See
also
molar pregnancy.)
molecule
The smallest complete unit of
a substance that can exist independ-
ently and still retain the characteristic
properties of that substance. Almost all
molecules consist of
2
or more atoms
that are bonded together. Molecules
that consist of only one atom are known
as monatomic molecules.
molluscum contagiosum
A harmless
viral infection characterized by shiny,
pearly white papules (tiny lumps) on
the skin surface. Each papule has a cen-
tral depression, and produces a cheesy
fluid when it is squeezed. A crust forms
before healing occurs.
The papules often appear on the geni-
tals, the inside of the thighs, or the face.
Children are more commonly affected
than adults. The infection is transmit-
ted by direct skin contact or during
sexual intercourse; it usually clears up
within a few months, but may last for
up to 18 months.
MOLLUSCUM CONTAGIOSUM
Pearly white papule
Mongolian
blue
spot A blue-black
pigmented spot found on the lower
back and buttocks at birth. The spots
are a type of
naevus
and are caused by a
concentration of melanocytes (pigment-
producing cells). Mongolian blue spots
are commonly found in black or Asian
children, and they usually disappear by
the age of 3-4 years.
Mongolism
An
outdated
name
for
Down's syndrome
.
moniliasis
See
candidiasis
.
monitor
To maintain a constant watch
on the condition of a patient. Also, any
device used to carry out monitoring.
monoamine oxidase inhibitors
Also
known as MAOIs, one of the 3 main
types of
antidepressant drug
. They work
by preventing the breakdown of certain
neurotransmitters
by the
enzyme
mono-
amine oxidase. The increased levels of
neurotransmitters that result are asso-
ciated with improved mood. Common
drugs include
phenelzine
and isocarbox-
azid. All MAOIs interact with certain
other drugs and foods such as cheese
and red wine; but
moclobemide
is known
as a reversible MAOI, which makes the
adverse reactions less likely to occur.
monoarthritis
Inflammation of a single
joint, causing pain and stiffness. Com-
mon causes of monoarthritis include
osteoarthritis
,
gout
,
and
infection
.
monoclonal
antibody
See
antibody,
monoclonal
.
monocyte
One of the main types of
white blood cell. Monocytes are
phago-
cytes
,
and play an important role in the
immune system
.
mononucleosis, infectious
An acute
viral infection characterized by a high
temperature, sore throat, and swollen
l}m ph nodes,
particularly in the neck.
Commonly called glandular fever, it is
caused by the
Epstein-Barr virus
and
is most common during adolescence or
early adulthood. One common mode of
transmission is thought to be kissing.
In the body, the virus multiplies in the
lymphocytes
(also called mononuclear
cells), which develop an atypical appear-
ance. The first symptoms are a fever and
headache, followed by swollen lymph
nodes and a severe sore throat. Rarely,
enlargement of the tonsils may obstruct
breathing. Mild inflammation of the
liver may occur, leading to
jaundice.
Diagnosis is often made from the symp-
toms and a blood test. Recovery usually
takes 4-6 weeks, with rest the only
treatment needed. In rare cases,
cortico-
steroid drugs
are given to reduce severe
inflammation, particularly if breathing
is obstructed. For 2-3 months after
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