H
glasses
follicle
Incision
Scalpel
Recipient
site
DONOR SITE
TRANSPLANTED
HAIRS
HALF-LIFE
HALLUX RIGIDUS
HAIR TRANSPLANT
Area of hair removal
Magnifying
Transplanted hair
Hair
STRIP GRAFTING TECHNIQUE
5 days. Transplanted hairs fall out shortly
afterwards, but new hairs grow from the
follicles 3 weeks to 3 months later.
Other transplant techniques include
punch grafting, in which a punch is used
to remove small areas of bald scalp,
which are replaced with areas of hairy
scalp; flap grafting, in which flaps of
hairy
skin
are
lifted,
rotated,
and
stitched to replace bald areas; and male
pattern
baldness
reduction,
which
involves cutting out areas of bald skin
and stretching surrounding areas of
hair-bearing scalp to replace them.
half-life
The time taken for the activity
of a substance to reduce to half its
original level. The term is usually used
to refer to the time taken for the level
of
radiation
emitted by a radioactive
substance to decay to half its original
level. The concept is useful in
radiother-
apy
for assessing how long material will
stay radioactive in the body. Half-life is
also used to refer to the length of time
taken by the body to eliminate half the
quantity of a drug.
halitosis
The medical
term
for bad
breath. Halitosis is usually a result of
smoking, drinking alcohol, eating garlic
or onions, or poor oral hygiene. Persis-
tent bad breath not caused by any of
these may be a symptom of mouth
infection,
sinusitis
, or certain lung disor-
ders, such as
bronchiectasis.
hallucination
A perception that occurs
when there is no external stimulus.
Auditory hallucinations (the hearing of
voices) are a major symptom of
schizo-
phrenia
but may also be caused by
manic-depressive illness
and
certain
brain disorders. Visual hallucinations are
most often found in states of
delirium
brought on by a physical illness (such
as
pneumonia
) or alcohol withdrawal
(delirium tremens). Hallucinogenic drugs
are another common cause of visual
hallucinations. Hallucinations of smell
are associated with
temporal lobe epi-
lepsy.
Those of touch and taste are rare,
however, and occur mainly in people
with
schizophrenia.
People subjected
to
sensory deprivation
or overwhelming
physical stress sometimes suffer from
temporary hallucinations.
hallucinogenic drug
A drug that caus-
es
hallucination.
Hallucinogens include
certain drugs of abuse, such as
LSD,
marijuana, mescaline,
and
psilocybin.
Some
prescription
drugs,
including
anticholinergic
drugs
and
levodopa
,
occasionally cause hallucinations.
hallux
The medical name for the big
toe.
hallux rigidus
Loss of movement in
the large joint at the base of the big
toe
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