DOXAZOSIN
chromosome number
21
has joined
w ith another chromosome. The parent
is unaffected but has a high risk of hav-
ing Down’s children.
SYMPTOMS
Typical physical features of a person
w ith Down’s syndrome include small
face and features; upward-sloping eyes
w ith folds of skin that cover their inner
corners; large tongue; flattened back to
the head; short, broad hands, with a
single horizontal crease on the palm
(see
simian crease
) ;
and short stature.
Learning difficulties
are very common,
and range from m ild to severe; howev-
er, affected people often have cheerful,
friendly personalities.
People with Down’s syndrome have a
greater than normal risk for certain dis-
orders. One possible problem is a heart
defect at birth (see
heart disease, congen-
ital
) ,
w hich affects up to two in five
babies. Others include intestinal
atresia
(a narrowing in the intestines)
and
congenital
deafness
.
Acute
leukaemia
is
more common than in other children.
Down’s
syndrome
children
are
also
especially susceptible to ear infections.
Affected adults over the age of 40 have
a higher than normal risk of develop-
ing
Alzheimer's disease
.
DIAGNOSIS
Screening tests during early pregnancy,
including a
nuchal thickness scan
(a form
of
ultrasound scanning
to measure the
skin at the back of the neck) indicate
those fetuses likely to have the syn-
drome.
Amniocentesis
is then offered;
this test involves
chromosome analysis
of
fetal cells. In some cases, Down’s syn-
drome is
only recognized once the
baby has been born. The diagnosis is
confirmed by chromosome analysis of
cells from the baby.
OUTLOOK
There is no cure for the condition, but
many Down’s syndrome children can
make the most of their capacities with
appropriate environmental and educa-
tional stimulation and support. Some
children learn skills such as reading
and writing, and some adults may be
able to work; however, most affected
people cannot live independently and
need long-term care from their families
or in a residential home.
doxazosin
An
antihypertensive drug
taken to reduce
high blood pressure (see
hypertension
) .
Possible side effects include dizziness,
headache, and nausea.
doxorubicin
An
anticancer drug
given by injection,
often with other anticancer drugs. It is
used in the treatment of a variety of
cancers, including
lung cancer
.
doxycycline
A
tetracycline drug
used in the treatment
of chronic
prostatitis
,
pelvic inflammatory
disease
,
acne,
and chest infection in
chronic
bronchitis
.
It is also used to pre-
vent and treat
malaria
.
Taking the drug
with food reduces possible side effects.
drainage angle
The gap between the outer edge of the
iris
(the coloured ring of muscle in the
eye)
and the
cornea
(the transparent
covering of the eyeball). This structure,
and the network of tissue behind it
(the trabecular network), allows excess
aqueous humour
to drain from the front
chamber of the eye. Blockage of the
drainage angle causes acute
glaucoma
.
drain, surgical
An appliance that is inserted into a body
cavity or a wound in order to release air
or permit drainage of fluid. Drains range
from simple soft rubber tubes that pass
from a body cavity into a dressing to
wide-bore tubes that connect to a col-
lection bag or bottle. Suction drains are
thin tubes containing many small holes
to help collect fluid or air, w hich is then
drawn into a vacuum bottle.
dream analysis
The interpretation of a person’s dreams
as part of
psychoanalysis
or
psychother-
apy
.
First developed by Sigmund Freud,
it is based on the idea that repressed
feelings and thoughts are revealed, in a
disguised way, in dreams.
dreaming
Mental activity that takes place during
sleep
.
Dreaming is thought to occur
only during periods of REM (rapid eye
movement) sleep, w hich last for about
20
minutes and occur four to five times
a night. Compared to other phases, the
REM phase of sleep is active. Blood
flow and brain temperature increase,
and there are sudden changes in heart
rate and blood pressure.
Dreams usually closely m irror the
day’s preoccupations. Dreaming can be
seen as a process in w hich the mental
impressions,
feelings,
and
ideas
are
sorted out. People roused during REM
sleep report especially vivid dreams.
dressings
Protective coverings for
wounds
that are
used to absorb blood or other body
secretions, prevent contamination,
or
retain moisture. Pressure dressings are
applied to stem bleeding or to reduce
swelling at the site of injury
Dressler’s syndrome
An uncommon disorder, also known
as postinfarction syndrome, that may
occur following a
myocardial infarction
(heart attack) or heart surgery Dressler’s
syndrome
is
characterized
by
fever,
chest pain,
pericarditis
(inflammation of
the membrane lining the heart), and
pleurisy
(inflammation of the
mem-
brane around the lungs). Treatment is
with
aspirin
or, in severe cases, with
cor-
ticosteroid drugs.
TYPES OF DRAINS
dribbling
Involuntary leakage of urine from the
bladder (see
incontinence, urinary
)
or of
saliva from the mouth (drooling). Drib-
bling of saliva is normal in infants. In
adults, it may be due to poorly fitting
dentures; alternatively, it may be the
result of facial paralysis, dementia, or
another disorder of the nervous system,
most
commonly
Parkinson’s
disease
.
Dribbling of saliva may also be caused
by an obstruction in the mouth that
interferes with swallowing.
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