EUNUCH
EVOKED RESPONSES
e u n u c h
A man whose
testes
have been
removed or destroyed so that he is ster-
ile and lacks male hormones. A male
who has been castrated before
puberty
will have broad hips, narrow shoulders,
and undeveloped male secondary
sexu-
al characteristics.
e u p h o r ia
A state of confident well-
being. Euphoria is a normal reaction to
personal success, but it can also be
induced by drugs, including prolonged
use of
corticosteroid drugs.
Euphoria
with no rational cause may be a sign of
mania,
or brain damage due to
head
injury, dementia, brain tumours,
or
mul-
tiple sclerosis.
e u s ta c h ia n tu b e
The passage that runs
from the
middle ear
into the back of the
nose, just above the soft
palate.
The
tube acts as a drainage channel from
the middle ear and maintains hearing
by opening periodically to regulate air
pressure. The lower end of the tube
opens during swallowing and yawning,
allowing air to flow up to the middle
ear, equalizing the air pressure on both
sides of the
eardrum.
When a viral infection such as a cold
causes blockage of the eustachian tube,
equalization cannot occur, resulting in
severe pain and temporary impairment
of hearing. A person with a blocked
eustachian tube who is subjected to
rapid pressure changes may suffer from
barotrauma. Glue ear
or chronic
otitis
media
may occur if the tube is blocked,
preventing adequate drainage from the
middle ear. These conditions, which
often result in partial hearing loss are
more common in children. This is partly
because their adenoids are larger and
more likely to cause a blockage if they
become infected and partly because
children's eustachhian tubes are shorter
than those of adults.
e u th a n a s ia
The use of medical know-
ledge to end a person's life painlessly in
order to relieve suffering. Euthanasia is
illegal in the UK.
e u th y r o id
The term used to describe a
person whose
ttynoid gland
is function-
ing normally, especially someone who
has been successfully treated for either
tyspottynoidism
or
tyqserttynoidism.
e v e n in g p r im r o s e o il
An oil that is
extracted from the seeds of the plant
Oenothera bien nis,
commonly known as
the evening primrose. The oil contains
an anti-inflammatory substance called
gamolenic acid, and is believed by
some to be of benefit in treating
eczem a
and
premenstrual s^mdrome.
EVENING PRIMROSE OIL
CAPSULES
EVENING PRIMROSE
e v e r s io n
A turning outwards. The term
is used medically to describe a type of
ankle injury or deformity in which the
foot is turned outwards,
e v id e n c e -b a s e d m e d ic in e
Health care
based on evidence, acquired through
expert practice and research, that a par-
ticular test or treatment is appropriate
for an individual patient,
e v o k e d r e s p o n s e s
The tracing of elec-
trical activity in the brain in response to
a specific external stimulus. The proce-
dure is similar to that for an
EEG.
The technique is used to check the
functioning of various sensory systems
(such as sight, hearing, or touch). The
information obtained can be used to
reveal abnormalities caused by
inflam-
mation,
pressure from a
tumour,
or other
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