Platelets or thrombocytes are the blood cells that are involved in the cellular mechanisms of primary haemostasis that lead to the formation of blood clots. Low levels or dysfunction predisposes for bleeding, while high levels, although usually asymptomatic, may increase the risk of thrombosis.
Anatomy
Like
red blood cells, platelets are anuclear (no
cell nucleus) and discoid (
disc shaped); they measure 1.5–3.0
μm in diameter. The body has a very limited reserve of platelets, so they can be rapidly depleted. They contain
RNA, a
canalicular system, and several different types of granules;
lysosomes (containing
acid hydrolases), dense bodies (containing
ADP,
ATP serotonin and
calcium) and alpha granules (containing
fibrinogen,
factor V,
vitronectin,
thrombospondin and
von Willebrand factor), the contents of which are released upon activation of the platelet. These granule contents play an important role in both
hemostasis and in the inflammatory response.
Physiology
Production
Platelets are produced in the
bone marrow; the progenitor cell for platelets is the
megakaryocyte. This large, multinucleated cell sheds platelets into the circulation.
Thrombopoietin (
c-mpl ligand) is a hormone, mainly produced by the
liver, that stimulates platelet production. It is bound to circulating platelets; if platelet levels are adequate, serum levels remain low. If the platelet count is decreased, more thrombopoeitin circulates freely and increases marrow production.
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Platelet - Twitter Search@ManiHeartsYou ngayon, mababa pa yung platelet count ko kaya kelangan ko ulit magpakuha ng blood, knina naging 130 na pero ang normal 150sherryxmusic (Sherry Yao) Wed, 23 Dec 2009 12:00:53 -0000
@ManiHeartsYou ngayon, mababa pa yung platelet count ko kaya kelangan ko ulit magpakuha ng blood, knina naging 130 na pero ang normal 150
Platelet Leukocyte-Enriched Gel (PLG) is a substance that is created by pheresing platelet-rich plasmaplatelettherapy (samantha b) Wed, 23 Dec 2009 09:47:32 -0000
Platelet Leukocyte-Enriched Gel (PLG) is a substance that is created by pheresing platelet-rich plasma
Thurrock Obama News: Chafford teen is country's youngest platelet donor:.. http://bit.ly/7fZpYL
News end. Believe!thurrock_obama (thurrock_obama) Wed, 23 Dec 2009 09:46:33 -0000
Thurrock Obama News: Chafford teen is country's youngest platelet donor:.. http://bit.ly/7fZpYL
News end. Believe!
Asthma Herbal Cures | IULREN.COM: The components found in ginger offsets the effects of the platelet-activating.. http://bit.ly/4yOnWzdarlene_647 (darlene) Wed, 23 Dec 2009 06:06:21 -0000
Asthma Herbal Cures | IULREN.COM: The components found in ginger offsets the effects of the platelet-activating.. http://bit.ly/4yOnWz
which is platelet type bleedin http://bit.ly/7TUhCh 1. epistaxis 2. epidural hemausmleforum (USMLE Forum) Wed, 23 Dec 2009 05:38:37 -0000
which is platelet type bleedin http://bit.ly/7TUhCh 1. epistaxis 2. epidural hema
New post, "Platelet-rich plasma discussion was most accessed Orthopedics Today article in ⦠â Ortho SuperSite" - http://bit.ly/5LindaBlog (Linda) Wed, 23 Dec 2009 02:19:32 -0000
New post, "Platelet-rich plasma discussion was most accessed Orthopedics Today article in … – Ortho SuperSite" - http://bit.ly/5
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Acquired Bleeding Disorders - An article by Thomas G. DeLoughery, Associate Professor of Medicine. Platelet transfusion therapy and dysfunctional platelets are discussed.
Meta Description: [ Hemonc Home ]
Adult Chronic Immune Thrombocytopenic Purpura - A guide for patients. A description of this disease followed by an in depth look.
Idiopathic Thrombocytopenic Purpura - ITP: A look at what these words actually mean, what he causes are, who gets it, diagnosis, how it affects children and adults and pregnant women.
Meta Description: [ Information about idiopathic thrombocytopenic purpura from the American Academy of Family Physicians. ]
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Immune Thrombocytopenic Purpura - A look at the symptoms, diagnosis and treatment of this disorder. Where to look for more information.
Meta Description: [ Immune Thrombocytopenic Purpura (ITP) ]
Immune Thrombocytopenic Purpura - What it is, symptoms of ITP, diagnosis, acute and chronic forms and treatment.
Meta Description: [ Idiopathic thrombocytopenic purpura (ITP) is a bleeding disorder in which the blood does not clot as it should. ]
Platelet Disorder Support Association - Information and support for those with immune thrombocytopenic purpura and other low platelet disorders
Meta Description: [ Comprehensive information and support for those concerned about ITP, Immune (Idiopathic) Thrombocytopenia Purpura. ]
Thrombocytopenia - Features information on this disorder and its causes, incidence and risk factors.
Thrombocytopenia During Pregnancy - An in depth look at gestational thrombocytopenia, idiopathic thrombocytopenic purpura, HELLP syndrome, toxemia of pregnancy, TTP and HUS, systemic lupus erythematosus and APA syndrome.
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Virtual Hospital: Bleeding Disorders - Differentiation of platelet versus coagulation defects, presentation, bleeding caused by qualitative platelet disorders and many more topics.
Meta Description: [ Virtual Hospital was a digital library of health information in pediatrics, paediatrics, and radiology for pediatric education and radiology education ]