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A 5-year-old girl with an enlarging mass at the elbow

Bradley John Kinney1, William L Hennrikus, Elizabeth E Frauenhoffer

  • 1Departments of Orthopaedics and Pathology, Pennsylvania State University College of Medicine, Hershey, PA 17033, USA.

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Changes in the Appendicular Skeleton with Age

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Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
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Bones of the Upper Limb: Ulna

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Abnormal Proliferation

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Abnormal Proliferation

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Skin Cancer01:30

Skin Cancer

Skin cancer is a type of cancer that occurs when there is an abnormal growth of skin cells, usually triggered by damage to the DNA within the skin cells. It is primarily caused by exposure to ultraviolet (UV) radiation from the sun or artificial sources like tanning beds. Skin cancer is the most common type of cancer worldwide, and its incidence continues to rise.
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Bones of the Upper Limb: Humerus

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