AORTITIS
APHRODISIAC
A
include fainting, lack of energy, chest
pain on exertion due to
angina,
and
breathing difficulty.
Chest X-ray, ECG,
and
echocardiogra-
phy
may be carried out to diagnose
aortic stenosis. A cardiac catheter can
be used to demonstrate the degree of
stenosis (see
catheterization, cardiac).
Heart-valve surgery
may be needed to
widen or replace the damaged valve.
aortitis
Inflammation of the
aorta
(the
main artery of the body). Aortitis is a
rare condition that occurs in people
with
arteritis
or untreated
syphilis
and in
some people with
ankylosing spondylitis.
Aortitis may cause part of the aorta to
widen and its walls to become thinner.
This may lead to an
aneurysm
(balloon-
ing of the artery). Aortitis may damage
the ring around the aortic valve in the
heart, leading to
aortic incom petence
.
aortography
An imaging technique that
enables the
aorta
(the main artery of the
body) and its branches to be seen clear-
ly on X-ray film following injection of a
contrast medium
(a substance that is
opaque to X-rays). Aortography is used
if surgery is needed to treat an
aneu-
rysm
(ballooning of the aorta).
aperient
A mild
laxative drug.
apex
The uppermost surface of a struc-
ture, for example the top, end, or tip of
an organ such as a lung or the heart.
apex
beat
A normal hearbeat felt
through the chest wall. As the heart con-
tracts, its tip hits the chest wall and can
be felt between the 5th and 6th ribs on
the left side of the chest. The apex beat
is displaced when the heart is enlarged.
Apgar
score
A system designed to
assess the condition of a newborn baby.
Five features are scored 1
minute and
again 5 minutes after birth. These are
breathing, heart-rate, colour, muscle
tone, and response to stimulation.
aphakia
The absence of the
lens
from
the eye. Aphakia may be congenital,
may result from surgery (for example,
cataract surgery
), or may be due to a
penetrating injury. Aphakia causes sev-
ere loss of focusing in the affected eye
and requires correction by implanting a
lens or with contact lenses or glasses.
aphasia
A complete absence of previ-
ously acquired language skills, caused
by a brain disorder that affects the abil-
ity to speak and write, and/or the ability
to comprehend and read. Related dis-
abilities that may occur in aphasia are
alexia
(word blindness) and
agraphia
(writing difficulty).
Language function in the brain lies in
the dominant cerebral hemisphere (see
cerebrum).
Two particular areas in this
hemisphere,
Broca's
and Wernicke's
areas, and the pathways connecting the
two, are important in language skills.
Damage to these areas, which most
commonly occurs as a result of stroke
or head injury, can lead to aphasia.
Some recovery from aphasia is usual
following
a
stroke
or
head
injury,
although the more severe the aphasia,
the less the chances of recovery.
Speech
therapy
is the main treatment. (See also
dysphasia
;
speech
;
speech disorders
.)
apheresis
A procedure in which blood
is withdrawn from a donor and is re-
infused after one or more selected
components have been separated and
removed. In plasmapheresis, antibodies
that are causing a disease are removed;
and in leukapher-
esis,
white blood
cells are removed.
aphonia
Complete
loss of the voice,
which
may result
from surgery to the
larynx
, or it may
be sudden in onset
and due to emo-
tional stress. (See
also
dysphonia.
)
aphrodisiac
Any
substance that is
APGAR SCORE
SIGN
SCORE 0
SCORE 1
SCORE 2
H eart-rate
None
Below 100 beats
per minute
Over 100 beats
per minute
Breathing
None
Weak cry; irregular
breathing
Strong cry; regular
breathing
Muscle tone
Limp
Some muscle
tone
Active
movement
Response to
stimulation
None
Grimace or
whimpering
Cry, sneeze
or cough
Colour
Pale; blue
Blue extrem ities
Pink
46
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