CUSP, DENTAL
CYST
include acne, stretch marks, bruising,
weakening of the bones by
osteoporosis,
susceptibility to infection and
peptic
ulcers,
and, in women, increased hairi-
ness. Mental changes frequently occur,
causing
depression, insomnia, paranoia,
or,
euphoria
.
Hypertension
,
oedema,
and
diabetes mellitus
may develop. In children,
growth may be suppressed.
The excess hormones are most com-
monly due to prolonged treatment with
corticosteroid
drugs
. Such
cases
of
Cushing's syndrome are usually mild. In
other cases, high hormone levels are
due to overactivity of the
adrenal glands
as a result of an
adrenal tumour
, or of a
pituitary tumour
affecting production of
ACTH
(adrenocortocotrophic hormone),
which stimulates the adrenal glands.
Cushing's syndrome caused by cortico-
steroid drugs usually disappears if the
dose is gradually reduced. A tumour of
an adrenal gland is removed surgically. A
pituitary tumour may be removed surgi-
cally or shrunk by irradiation and drug
treatment. In both cases, surgery is fol-
lowed by
hormone replacement therapy
.
cusp, dental
A protrusion on the grind-
ing surface of a
tooth
.
cutaneous
Relating to the skin.
cutdown
Creation of a small skin inci-
sion in order to gain access to a
vein
to
take blood or to give intravenous fluid.
This is sometimes needed when a vein
cannot be identified through the skin in
conditions such as shock.
cuticle
The outermost layer of skin. The
term commonly refers to the thin flap of
skin at the base of a nail; and also to
the outer layer of a hair shaft.
CROSS SECTION OF FINGERTIP
CVS
The abbreviation for
chorionic villus
sampling
and for
cardiovascular system.
cyanide
Any of a group of salts of hydro-
cyanic acid. Most are highly poisonous;
inhalation or ingestion can rapidly lead
to breathlessness,
paralysis
, and death.
cyanocobalamin
An alternative name
for
vitamin B12.
cyanosis
A bluish coloration of the skin
or mucous membranes due to too much
deoxygenated
haemoglobin
in the blood.
Cyanosis confined to the hands and feet
is not serious and is usually due to slow
blood flow, often as a result of exposure
to cold. A blue tinge to the lips and
tongue, however, could be due to a heart
or lung disorder such as chronic obstruc-
tive
pulmonary disease
or
heart failure
.
cyclopenthiazide
A
thiazide diuretic
drug
used to reduce
oedema
associated with
heart failure
, kidney disorders,
cirrhosis
of the liver, and
premenstrual syndrome
,
and to treat
hypertension
. Side effects
include lethargy, loss of appetite, leg
cramps, dizziness, rash, and impotence.
cyclophosphamide
An
anticancer drug
used in the treatment of
Hodgkin's dis-
ease
and
leukaemia
. It is also used as an
immunosuppressant drug
and occasion-
ally to treat connective tissue diseases
such as systemic
lupus erythematosus
.
cycloplegia
Paralysis
of the ciliary mus-
cle of the eye impeding
accommodation
.
Cycloplegia may be induced by cyclople-
gic drugs to facilitate eye examinations.
cyclosporin
An alternative spelling for
ciclosporin.
cyclothymia
A personality characteris-
tic typified by marked changes of mood
from cheerful, energetic, and sociable to
gloomy, listless, and withdrawn. Mood
swings may last for days or months and
may follow a regular pattern.
cyproterone acetate
A drug that blocks
the action of
androgen hormones
and is
used in the treatment of cancer of the
prostate (see
prostate, cancer of
) and oc-
casionally to reduce male sex drive. Side
effects include weight gain and an in-
creased risk of developing of blood clots.
cyst
An abnormal and usually harmless
lump or swelling, filled with fluid or
semi-solid material. Cysts occur in body
organs or tissue. Types of cysts include
sebaceous cysts
,
dermoid cysts, ovarian
155
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