EXERCISE
reveal abnormalities caused by inflam-
mation, pressure from a tumour, or
other disorders, and to help confirm a
diagnosis of
multiple sclerosis
.
Ewing’s sarcoma
A rare malignant form of
bone cancer
.
Ewing’s sarcoma arises in a large bone,
usually the
femur
(thigh bone),
tibia
,
(shin),
humerus
(upper-arm bone), or
a pelvic bone, and spreads to other
areas at an early stage. The condition is
most common in children between ten
and 15 years of age.
SYMPTOMS
A bone affected by Ewing’s sarcoma is
painful and tender. It may also become
weakened and fracture
easily.
Other
symptoms include weight loss, fever,
and
anaemia
(a reduced level of the
oxygen-carrying
pigment haemoglo-
bin in the blood).
DIAGNOSIS AND
TREATMENT
The sarcoma can be diagnosed by
X-rays
and
biopsy
(removal of a small sample
of tissue for microscopic analysis). If
cancer is found, the whole skeleton is
examined by X-rays and
radionuclide
scanning
,
and the lungs viewed by
CT
scanning
,
to determine if, and how far,
the cancer has spread.
Treatment
of Ewing’s
sarcoma
is
with
radiotherapy
and
anticancer drugs
.
The outlook depends on how far the
cancer has spread.
examination, physical
The part of a medical consultation in
w hich the doctor looks at, feels, and lis-
tens to various parts of the patient’s
body. A physical examination is used
to assess the patient’s condition or to
gather information to help the doctor
make a
diagnosis
.
Most physical examinations include
palpation
(feeling w ith the hands), by
w hich
the
doctor
examines relevant
areas of the body for signs such as
swelling,
tenderness,
or
enlargement
of organs. In some cases,
percussion
of
the chest, or other parts of the body,
may be performed by tapping with the
fingers and then listening to the sound
produced.
Auscultation
(listening with a
stethoscope) may be used to listen to
blood flow through the arteries and
sounds made by the heart and lungs.
Other aspects of the examination may
involve taking the patient’s pulse or
blood pressure
,
examining his or her
eyes and ears, and assessing the strength
and coordination of the muscles.
exanthema
A skin eruption or rash, or a disease in
w hich a skin eruption or rash is a
prominent
feature,
such
as
measles
,
scarlet fever
,
or
roseola infantum
.
exchange transfusion
A treatment for
haemolytic disease of the
newborn
,
a
severe
disorder
resulting
from
rhesus incompatibility
between a
pregnant mother and her baby and
causing destruction of red blood cells in
the baby. This condition leads to dan-
gerously high levels of the pigment
bilirubin
in the baby’s blood as well
as severe
anaemia
(a reduced level of the
oxygen-carrying pigment haemoglobin
in the blood).
Exchange
transfusion
is used to treat both these symptoms
by replacing the infant’s blood with
rhesus-negative donor blood.
excimer laser
A computer-controlled
laser
used to
reshape
the
cornea
(the
transparent
dome that forms the front of the eye-
ball). The laser removes very thin layers
of tissue from the corneal surface (see
LASIK
;
PRK
) .
The technique is used to
correct
myopia
(shortsightedness),
hyper-
metropia
(longsightedness), and some
other vision disorders.
excision
The surgical cutting out of diseased
tissue, such as a breast lump or gan-
grenous skin, from surrounding healthy
tissue. (See also
excisional biopsy
. )
excisional biopsy
A type
of
biopsy
that
involves
the
removal of an entire area of affected
tissue, together w ith a margin of adja-
cent healthy tissue,
for microscopic
analysis in a laboratory.
exclusion diet
A dietary programme that is used to
identify a particular
food allergy
or
food
intolerance.
Food is initially limited to a
very restricted choice until symptoms
improve; test foods, such as milk, are
then reintroduced one at a time, at
intervals of several days, to see if there
is an adverse reaction. The reintroduc-
tion of such a test food is known as a
food challenge.
Individuals on an exclusion diet are
asked to keep a daily record of their
symptoms from at least a week before
starting the diet until the end of the
programme. An exclusion diet should
never be attempted without the advice
of a doctor, dietitian, or nutritionist
because it can result in serious nutri-
tional deficiencies.
excoriation
Injury to the surface of the skin or to a
mucous membrane
(the thin, moist tissue
that lines body cavities) caused by phys-
ical
abrasion
,
such as scratching.
excrescence
Any abnormal raised growth on the sur-
face of the body, such as a
wart
.
excretion
The discharge of any waste material
from the body. Examples of such waste
material are the by-products of diges-
tion, waste products from the repair of
tissues, and excess water.
ORGANS OF EXCRETION
The
kidneys
excrete urine, w hich con-
tains excess nitrogen (as urea), together
w ith excess water, salts, some acids, and
most
drugs. The
liver
excretes
bile,
w hich contains waste products and bile
pigments formed from the breakdown
of red blood cells. Some of the bile is
passed from the body in the
faeces
.
The
large
intestine
excretes undigested food,
some salts, and excess water in the form
of faeces. The
lungs
discharge carbon
dioxide and water vapour into the air.
Sweat glands
excrete salt and water onto
the surface of the skin as a method of
regulating the body’s temperature.
exencephaly
A developmental defect of the cranium
(skull) in w hich part of the bone is
absent, leaving the brain exposed or
allowing it to protrude. This defect is
incompatible with survival.
exenteration
The surgical removal of all organs and
soft tissue in a body cavity, usually to
arrest the growth of a
cancer
.
Exentera-
tion is sometimes used in
ophthalmology
when the eye and the contents of the
eye socket are removed.
exercise
Any
physical
activity
performed
to
improve health. Exercise may be taken
for recreation or to correct a physical
injury or deformity (see
physiotherapy
) .
TYPES OF EXERCISE
Different types of exercise have differ-
ent effects on the body. Some forms
(aerobic exercises) improve the fitness
E
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