GASTROENTERITIS
G
HORMONES IN THE DIGESTIVE TRACT
Hormones released from endocrine
cells in the stomach, pancreas, and
intestine aid digestion by stimulating
the release of bile from the gallbladder
and enzymes from the pancreas into
the duodenum.
C h o l e c y s t o k i n i n
___________
R e l e a s e d b y t h e d u o d e n u m
in r e s p o n s e t o f a t s a n d a c id ,
c h o l e c y s t o k i n i n c a u s e s t h e
g a l l b l a d d e r t o s q u e e z e b i l e in t o
t h e d u o d e n u m a n d s t i m u l a t e s
t h e p r o d u c t i o n o f p a n c r e a t i c
e n z y m e s , w h i c h p a s s in t o
t h e d u o d e n u m t h r o u g h t h e
p a n c r e a t i c d u c t .
G a s t r in
S e c r e t e d m a i n l y b y c e l l s in t h e s t o m a c h in
r e s p o n s e t o e a t i n g f o o d ( e s p e c i a l l y p r o t e i n ) ,
g a s t r i n c a u s e s t h e s t o m a c h t o p r o d u c e m o r e
a c i d a n d s t i m u l a t e s c o n t r a c t i o n o f m u s c l e in
t h e w a l l o f p a r t o f t h e s t o m a c h , ile u m , a n d
c o l o n . T h is c o n t r a c t i o n p r o p e l s f o o d t h r o u g h
t h e d i g e s t i v e tra c t.
S e c r e t i n
________________
S e c r e t e d b y t h e lin in g o f t h e
d u o d e n u m in r e s p o n s e t o a c i d
e n t e r i n g f r o m t h e s t o m a c h ,
s e c r e t i n a c t s o n t h e p a n c r e a s
t o i n c r e a s e t h e o u t p u t o f
b i c a r b o n a t e , w h ic h n e u t r a l i z e s
a c i d f r o m t h e s t o m a c h . I t a l s o
i n c r e a s e s t h e r e l e a s e o f
e n z y m e s f r o m t h e p a n c r e a s .
O e s o p h a g u s
F o o d e n t e r s
t h e s t o m a c h
D u o d e n u m
P a n c r e a s
gastroenteritis
Inflammation
of the
stomach
and intes-
tines,
usually
causing
sudden upsets
that last for two or three days.
Dysentery,
typhoid fever, cholera, food poisoning,
and
travellers’ diarrhoea
are
all
forms
of
gastroenteritis. Gastroenteritis may be
caused by a variety of
bacteria,
bacterial
toxins, viruses,
and other organisms in
food or water. There are also a number
of non-infectious causes, such as
food
intolerance
and certain irritant drugs.
The usual symptoms are appetite loss,
nausea, vomiting,
cramps, and diar-
rhoea. Their onset and severity depend
on the cause; symptoms may be mild,
or may be so severe that
dehydration
,
shock,
and collapse occur.
M ild cases usually require rest and
rehydration therapy
only. For severe ill-
ness,
treatment
in
hospital
may
be
necessary, with fluids given by
intra-
venous infusion. Antibiotic drugs
may be
given for some bacterial infections, but
others need no specific treatment.
gastroenterology
The study of the
digestive system
and the
diseases and disorders that affect it.
gastroenterostomy
Surgery that is performed to create a
connection between the
stomach
and
the
jejunum
(the middle two thirds of
the small intestine), sometimes com-
bined with a partial
gastrectomy
(the
removal of the lower part of the stom-
ach). The operation, formerly carried
out to treat duodenal ulcer (see
peptic
ulcer
), is now rarely performed.
gastrointestinal hormones
A group of
hormones
released from spe-
cialized cells in the
stomach
,
pancreas
,
and small intestine that control various
functions of the digestive organs.
Gastrin,
secretin,
cholecystokinin,
and
vasoactive
intestinal polypeptide
are the best known
of these hormones (see
Hormones in the
digestive trac
t), but new hormones are
still being discovered.
gastrointestinal tract
The part of the
digestive system
consist-
ing of the
mouth
,
oesophagus
,
stomach
,
and
intestines.
These structures together
form a long tube through w hich food
passes as it is digested.
gastro-oesophageal reflux
disease (GORD)
The medical term for
acid reflux
.
gastroscopy
Examination of the
stomach
via a flexible
endoscope
(a viewing instrument) insert-
ed through the mouth. The
oesophagus
and
duodenum
(the first part of the small
intestine) are also inspected; for this rea-
son, the procedure is more accurately
called an oesophagogastroduodenoscopy.
The patient is often sedated throughout.
Gastroscopy
is
used to investigate
bleeding,
or
other disorders,
of the
oesophagus,
stomach,
or duodenum.
Attachments to the gastroscope enable a
biopsy
(removal of a tissue sample for
analysis) to be carried out, as well as
treatments such as
laser treatment
.
A gas-
troscope may also be used to ease the
passage of a gastric feeding tube through
the skin (see
gastrostomy
) .
gastrostomy
A surgically
created
opening in the
stomach
.
It is usually made to connect
the stomach to the outside of the body,
so that a feeding tube can be passed
into the stomach or small intestine.
Gastrostomy may be perform ed on
people w ho cannot eat properly due
to oesophageal cancer (see
oesopha-
gus, cancer of
) or w ho are unable to
chew and swallow due to a
stroke
.
Gaucher’s disease
A
genetic disorder
in w hich the lack of
the
enzyme
glucocerebrosidase leads to
accumulation of a fatty substance, glu-
cosylceramide, in the liver, spleen, bone
marrow, and, sometimes, in the brain.
The condition is treated by regular in -
jections of the missing enzyme.
gauze
An absorbent, open-weave fabric, usu-
ally made of cotton. Sterilized gauze is
often used to clean wounds, or applied
as a
dressing
to soak up fluids from
wounds. It is not used on areas of dam-
aged tissue such as burns or ulcers,
because it may stick to the surface and
dislodge new tissue when it is removed.
gavage
Feeding of liquids through a
nasogastric
tube
,
w hich is passed into the stomach
through the nose (see
feeding, artificial
) .
The term “ gavage” can also refer to
hyperalimentation
(treating a patient by
feeding beyond appetite requirements).
gel
A jelly-like suspension consisting
of
small, insoluble particles that are dis-
persed through a liquid. Gels are often
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