GLOSSOLALIA
GLYCEROL
G
Glossitis occurs in various forms of
anaemia
and in
vitamin B
deficiency.
Other causes include infection of the
mouth (especially by
herpes simplex),
irritation by dentures, and excessive use
of alcohol, tobacco, or spices. Treat-
ment is
for
the
underlying
cause.
Rinsing of the mouth with a salt solu-
tion and good
oral hygiene
may help.
glossolalia
Speaking in an imaginary
language that has no actual meaning or
syntax. (See also
neologism.)
glossopharyngeal
nerve
The ninth
cranial nerve.
This nerve performs both
sensory and motor functions. It conveys
sensations, especially taste, from the
back of the
tongue
, regulates secretion
of saliva by the
parotid gland
, and con-
trols movement of the throat muscles.
glottis
The part of the
larynx
that con-
sists of the
vocal cords
and the slit-like
opening between them.
glucagon
A
hormone
that stimulates
the breakdown of stored
glycogen
into
glucose
and is released by the
pancreas
when the blood level of glucose is low.
Glucagon is used as an injected drug
in the emergency treatment of people
with
diabetes mellitus
who are uncon-
scious as a result of low blood glucose.
Nausea and vomiting are occasional
adverse effects.
glucocorticoids
Hormones
produced by
the cortex of the
adrenal glands
that
affect carbohydrate metabolism by in-
creasing the blood sugar level and are
also involved in the body's response to
physical stress. The main glucocorticoid
is
hydrocortisone
.
glucosamine
A molecule that occurs
naturally as a component of various
substances in the body, including
colla-
gen
. Glucosamine is also sold as a food
supplement and is recommended to
relieve symptoms of
arthritis.
glucose
A simple
sugar
that is naturally
present in fruits and is a product of
the digestion of
starch
and sucrose. It is
the chief source of energy for the body
and is carried to all tissues in the
blood. The term blood sugar refers to
glucose in the bloodstream.
The level of glucose in the blood is
normally kept fairly constant by the
actions of various
hormones
, notably
insulin
,
glucagon
,
adrenaline
,
cortico-
steroid hormones
,
and
growth hormone
.
An abnormally high blood glucose level
(known as
hyperglycaemia
) may cause
glucose to be lost into the urine. An
abnormally low blood glucose level is
called
hypoglycaemia
.
glue ear
Accumulation of fluid in the
cavity of the
middle ear
, causing im-
paired hearing. Persistent glue ear is
most common in children. It is often
accompanied by enlarged
adenoids
and
frequently occurs with viral respiratory
tract infections, such as the common
cold
. Usually both ears are affected. The
lining of the middle ear becomes over-
active,
producing large amounts of
sticky fluid, and the
eustachian tube
becomes blocked so that the fluid
cannot drain away. The accumulated
fluid interferes with the movement of
the delicate bones of the middle ear.
Glue ear is sometimes first detected by
hearing tests
.
Examination with an
oto-
scope
can confirm the diagnosis. In mild
cases, the condition often clears up with-
out specific treatment. If the condition
persists, it may be necessary to insert
grommets
, which allow air into the mid-
dle ear and encourage fluid to drain.
Adenoidectomy
may also be required.
glue-sniffing
See
solvent abuse
.
glutaraldehyde
A
topical
preparation
for the treatment of
warts
, particularly
plantar warts
. Glutaraldehyde may cause
a rash or irritation and may stain the
skin brown.
gluten
A combination of gliadins and
glutenins (types of proteins) formed when
certain cereal flours (notably wheat flour)
are mixed with water. Sensitivity to
gluten causes
coeliac disease
.
gluten enteropathy
See
coeliac disease
.
gluten intolerance
See
coeliac disease
.
gluteus maximus
The large, powerful
muscle
in each of the buttocks that
gives them their rounded shape. The glu-
teus maximus is responsible for moving
the thigh sideways and backwards.
glycerol
A colourless syrupy liquid that
has a sweet taste. Glycerol is prepared
from
fats and oils
; it is an essential con-
stituent of
triglycerides
(simple fats).
In rectal
suppositories
, glycerol relieves
constipation
by softening hard faeces.
254
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