اللفائفي

(تم التحويل من Ileum)
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Illu small intestine.jpg
الأمعاء الدقيقة
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الحفرة الأعورية. اللفائفي والأعور مسحوبين للخلف ولأعلى.
Details
Precursor منصف البطن midgut
Artery الشرايين المعوية
Nerve العقد البطنية celiac ganglia, المبهم vagus [1]
Identifiers
TA خطأ لوا في وحدة:Wikidata على السطر 744: attempt to index field 'wikibase' (a nil value).
TH {{#property:P1694}}
TE {{#property:P1693}}
FMA FMA:{{#property:P1402}}
Anatomical terminology
[[[d:خطأ لوا في وحدة:Wikidata على السطر 863: attempt to index field 'wikibase' (a nil value).|edit on Wikidata]]]

في تشريح الجهاز الهضمي, اللفائفي ileum هو القسم الأخير من الأمعاء الدقيقة. ويبلغ طولها نحو 2-4 م في الإنسان, وتأتي بعد الإثنى عشر duodenum و الصائم jejunum, ويفصلها عن الأعور cecum الصمام اللفائفي الأعوري|الصمام اللفائفي الأعوري ileocecal valve (ICV). درجة القاعدية pH في اللفائفي عادة ما تتراوح بين 7 و 8 (متعدل أو بالكاد قاعدي).

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الوظيفة

وظيفته في الأساس هي امتصاص فيتامين ب12 و أملاح الصفراء وأية نواتج من الهضم لم يمتصها الصائم. The wall itself is made up of folds, each of which has many tiny finger-like projections known as villi, on its surface. In turn, the epithelial cells which line these villi possess even larger numbers of microvilli. Therefore the ileum has an extremely large surface area both for the adsorption (attachment) of enzyme molecules and for the absorption of products of digestion. The DNES (diffuse neuroendocrine system)cells that line the ileum contain the protease and carbohydrase enzymes (gastrin, secretin, cholecystokinin) responsible for the final stages of protein and carbohydrate digestion. These enzymes are present in the cytoplasm of the epithelial cells. The villi contain large numbers of capillaries which take the amino acids and glucose produced by digestion to the hepatic portal vein and the liver.

Lacteals are small lymph vessels, and are present in villi. They absorb fatty acid and glycerol, the products of fat digestion. Layers of circular and longitudinal smooth muscle enable the digested food to be pushed along the ileum by waves of muscle contractions called peristalsis.


الفروقات بين الصائم واللفائفي

There is no line of demarcation between the jejunum and the ileum. There are, however, subtle differences between the two.

  • The ileum has more fat inside the mesentery than the jejunum.
  • The ileum is a paler color, and tends to be of a smaller caliber as well.
  • While the length of the intestinal tract contains lymphoid tissue, only the ileum has abundant Peyer's patches.

These unencapsulated lymphoid nodules contain large amounts of lymphocytes and other cells of the immune system.

علم الأجنة

In the fetus the ileum is connected to the navel by the vitelline duct. In roughly 3% of humans, this duct fails to close during the first seven weeks after birth, causing a condition called Meckel's diverticulum.

تشريح حيواني

In veterinary anatomy, the ileum is distinguished from the jejunum by being that portion of the jejunoileum that is connected to the caecum by the ileocaecal fold.

صور اضافية

المصدر

وصلات خارجية