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split-out non-tumour stuffs in bone tumours
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# | '''Bone''' is a scaffold. Tumours occasionally arise in them; these are dealt with in the ''[[bone tumours]]'' article. | ||
==Normal== | |||
*Normal bone has osteocytes. | |||
**If the osteocytes are missing... the bone is dead. | |||
*Osteoblasts - make bone. | |||
*Osteoclasts - destroy bone. | |||
Memory device: 'b' before 'c'. | |||
===Bone marrow=== | |||
*Fat content (%) ~= age (in years)<ref>IAV. 26 Feb 2009.</ref> | |||
**e.g. 60 year old will have 60% fatty replacement. | |||
*Should see three cell lines. | |||
**The cell lines:<ref>[http://emedicine.medscape.com/article/199003-overview http://emedicine.medscape.com/article/199003-overview]</ref> | |||
***Erythroid (red cells), | |||
***Myeloid (white blood cells), | |||
***Megakaryocytic (platelets). | |||
Note: Lymphocytes are considered separately and typically spared in bone marrow failure.<ref>[http://emedicine.medscape.com/article/199003-overview http://emedicine.medscape.com/article/199003-overview]</ref> | |||
Identifying the lines:<ref>[http://upload.wikimedia.org/wikipedia/commons/6/69/Hematopoiesis_%28human%29_diagram.png http://upload.wikimedia.org/wikipedia/commons/6/69/Hematopoiesis_%28human%29_diagram.png]</ref> | |||
#Megakaryocytes: | |||
#*Big cells ~ 3x the size of a RBC. | |||
#Normoblasts (RBC precursors): | |||
#*Hyperchromatic, i.e. blue, nucleus. | |||
#Myeloid line: | |||
#*Granules. | |||
#*Reniform nucleus, i.e. kidney bean shaped nucleus. | |||
Images: | |||
*[http://commons.wikimedia.org/wiki/File:Bone_marrow_WBC.JPG Myeloid line (WC)]. | |||
====Organization==== | |||
*Mature hematopoeitic cells at the centre (distant from bone). | |||
*Immature hematopoeitic cells adjacent to the bone. | |||
==Infectious== | |||
===Osteomyelitis=== | |||
General | |||
*Hematogenous - often in children. | |||
*Direct entry (skin defect) - adults with diabetes. | |||
====Microscopic==== | |||
*PMNs. | |||
===Chronic osteomyelitis=== | |||
*Plasma cells. | |||
**May be sterile, i.e. no organisms. | |||
==Bone tumours== | |||
{{Main|Bone tumours}} | |||
This is a big topic. It is dealt with in a separate article. | |||
==See also== | |||
*[[Hematopathology]]. | |||
*[[Soft tissue lesions]]. | |||
*[[Small round cell tumours]]. | |||
==References== | |||
{{reflist|2}} | |||
[[Category:Weird stuff]] | |||