CELLULITIS
CEREBELLUM
C
daughter cells identical to the parent
cells.
Meiosis
produces egg (see
ovum)
and
sperm
cells that differ from their
parent cells in that they have only half
the normal number of
chromosomes.
cellulitis
A bacterial infection of the skin
and the tissues beneath it, usually affect-
ing the face, neck, or legs. Cellulitis is
most commonly caused by streptococci
bacteria, which enter the skin via a
wound. The affected area is hot, tender,
and red, and there may be fever and
chills. Untreated cellulitis at the site of a
wound may progress to
bacteraem ia
and
septicaemia
or, occasionally, to
gangrene.
Cellulitis is usually more severe in peo-
ple with reduced immune response, such
as those with
diabetes mellitus
or an
immunodeficiency disorder
. Treatment is
with an
antibiotic
such as a
penicillin
drug
or
erythromycin.
(See also
erysipelas.)
celsius scale
A temperature scale in
which the melting point of ice is zero
degrees (0°C) and the boiling point of
water is 100 degrees (100°C). On this
scale, normal body temperature is 37°C.
(See also
Fahrenheit scale.)
cementum
Bone-like tissue surround-
ing the root of a tooth (see
teeth
).
centigrade scale
The obsolete name
for the
celsius scale
.
central nervous system
The anatomi-
cal term for the
brain
and
spinal cord
,
often abbreviated as CNS. The central
nervous system is made up of neurons
(nerve cells) and works in tandem with
the
peripheral nervous system
(PNS),
which carries signals between the CNS
and the rest of the body. The CNS is
responsible for receiving sensory infor-
mation from organs such as the eyes
and ears, analysing it, and then initiat-
ing an appropriate motor response. (See
also
nervous system.)
centrifuge
A machine that separates
the different components of a body fluid
for analysis. When a fluid such as blood
is spun at high speed around a central
axis, groups of particles of varying den-
sity, for example red and white blood
cells, are separated by centrifugal force.
cephalexin
An alternative spelling of
cefalexin, a common
cephalosporin drug
.
cephalhaematoma
An extensive, soft
swelling on the scalp of a newborn infant,
which is caused by bleeding into the
space between the
cranium
and its
fibrous covering due to pressure on the
baby's head during delivery. The swelling
is not serious and gradually subsides.
cephalic
Relating to the head, as in
cephalic presentation, the head-first
position of a baby in the birth canal.
cephalopelvic disproportion
A com-
plication of childbirth (see
childbirth,
complications of
) in which the mother's
pelvis is too narrow in proportion to the
size of the baby's head.
cephalosporin drugs
A large group of
antibiotic drugs
derived from the fungus
CEPHALOSPORIUM ACREMONIUM,
which are
effective against a wide range of infec-
tions. Cephalosporins are used to treat
ear, throat, and respiratory tract infec-
tions, and conditions, such as
urinary
tract infections
and
gonorrhoea,
in which
the causative bacteria are resistant to
other types of antibiotics. Occasionally,
the drugs cause allergic reactions, such
as rash, itching, and fever. Rarely,
anaphy-
lactic shock
occurs. Other side effects
include diarrhoea and
blood disorders
.
cerebellar ataxia
Jerky, staggering gait
and other uncoordinated movements
caused by a disease of or damage to
the
cerebellum
. Other features include
dysarthria
(slurred speech), hand tremor,
and
nystagmus
(abnormal jerky eye
movements). Possible causes include
stroke
,
multiple sclerosis
, a
brain tumour
,
damage caused by
alcohol dependence
,
and degeneration of the cerebellum due
to an inherited disorder.
cerebellum
A region of the brain behind
the
brainstem
concerned with maintain-
ing posture and balance and coordinating
movement. The cerebellum is situated
behind the
brainstem
and has
2
hemi-
spheres. From the inner side of each
hemisphere arise 3 nerve fibre stalks,
which link up with different parts of the
brainstem and carry signals between
the cerebellum and the rest of the
brain. Nerve fibres from these stalks fan
out towards the deep folds of the
cortex
(outer part) of each brain hemisphere,
which consists of layers of
grey matter
.
Information about the body's posture
and the state of contraction or relax-
ation in its muscles is conveyed from
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