انت هنا الان : شبكة جامعة بابل > موقع الكلية > نظام التعليم الالكتروني > مشاهدة المحاضرة
الكلية كلية طب الاسنان
القسم العلوم الاساسية
المرحلة 3
أستاذ المادة علي زكي ناجي الاسدي
5/31/2011 6:57:12 AM
Tissue repair &wound healing:
Healing is a tissue response to wound, inflammation and necrosis, and it’s consist of variable proportion of two distinct processes (Regeneration & scar formation).
1- Regeneration : replacement of damaged tissue by proliferation of adjacent surviving specialized parenchymal cells, like in healing of superficial skin wound that affect only the skin epidermis, so the tissue can completely reconstituted after injury.
2- Scar formation : replacement of damaged tissue by granulation tissue formation and then mature into fibrous tissue, like in healing of deep wound that affect the dermis, and also in healing of internal organs like in scar formation in the heart at site of myocardial infarction.
The type of process for healing influenced by:
1- Type of tissue affected.(hepatocytes can regenerate while neurons can not).
2- Severity and duration of injury. (superficial and small skin wounds heal by regeneration, while deep and sever wounds heal by scar formation).
The cells in the body divide into three types according to proliferation ability:
1- Labile cells: these cells are in continuous division and death, (surface epithelial cells, and stem cells of the bone marrow).
2- Stable cells: these cells have low level of replication capacity in normal state, but they can undergo rapid division in response to injury like parenchymal cells of liver and kidney.
3- Permanent cells: these are specialized non-dividing cells, so they can not replaced by identical cells after injury, like neurons and cardiac muscles).
Role of Extacellular Matrix (ECM), in healing process:
1- provides scaffolding for tissue renewal.
2- Provide mechanical support for the cells.
3- Determine cell orientation (polarity of the tissue).
1- Regulate cell growth and differentiation.
Fibrosis: indicates repair by connective tissue. Its involves the following steps:
1- Angiogenesis, (formation of new blood vessels).
2- Migration and proliferation of fibroblasts.
3- Deposition of extacerlualr matrix.
4- Maturation and remodeling of the tissue.
Orderly phenomenon of wound healing involving the following processes:
1- Induction of an acute inflammatory process by the initial injury
2- Regeneration of parenchymal cells
3- Migration and proliferation of both parenchymal and connective tissue cells
4- Synthesis of extracellular matrix ( ECM )proteins
5- Remodeling of connective tissue and parenchymal components
6- Collagenizaton and acquisition of wound strength
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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