Articles
Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.
319 results found
Article
Well differentiated fetal adenocarcinoma of lung
A well-differentiated fetal adenocarcinoma (WDFA) of lung is a rare low grade lung tumor. Some consider this as a variant of adenocarcinoma with others considering this under the group of pulmonary blastomas 5.
According to classification by the World Health Organization in 1999, it was remove...
Article
HER-2 mutations in lung cancer
Human epidermal growth factor receptor 2 (HER-2) mutations may be detected in approximately 3% of lung adenocarcinomas 1.
Radiographic features
CT
Early studies have suggested HER2-mutant tumors exhibit more aggressive features in general and tend to:
exhibit a locally-invasive behavior comp...
Article
Hepatoblastoma histological classification
Although hepatoblastomas can be histologically classified into a variety of subtypes, it is important to remember that with the possible exception of small cell undifferentiated subtype, prognosis is independent of histology when adjusted for stage gender and age 1.
major categories
epithelial...
Article
Cyst
A cyst is an abnormal fluid-filled structure which is lined by epithelium; with one exception: lung cysts may contain gas or fluid. By contradistinction, a pseudocyst lacks an epithelial lining and instead has a vascular and fibrotic capsule.
Cysts are extremely common and found in most organs....
Article
Probabilistic atlas
Probabilistic atlases, also known as probability maps, are anatomical or anatomopathological atlases based on statistically-weighted composites of many specimens. Traditional anatomy atlases were based on one or a few specimens sometimes with common variations indicated or shown. Probabilistic a...
Article
Vitamin D deficiency (overview)
Vitamin D deficiency (also known as hypovitaminosis D) is common, and untreated, may result in serious sequelae. Traditionally its pathological manifestations have been regarded through the lens of skeletal maturity:
rickets in children
osteomalacia in adults
However it has become increasingl...
Article
Monomelic
Monomelic is typically used to refer to a condition that is confined to only one limb. Examples of conditions that can be monomelic include fibrous dysplasia and melorheostosis.
See also
monostotic
polyostotic
monomelic
Article
Lead
Lead (chemical symbol Pb) is a toxic metallic element with no known biological function in humans.
Chemistry
Basic chemistry
Lead is one of the post-transition metals with the atomic number 82 and atomic weight 207.2. It is grayish in color and is pliable, poorly electrically-conducting with ...
Article
Basic organic elements
The basic organic elements are those chemical elements that are fundamental to life and are constituents of every or almost every organic molecule, and therefore all life known on earth.
carbon
hydrogen
oxygen
nitrogen
Article
Chromogranin A
Chromogranin A (CgA) is an acidic secretory glycoprotein found in the secretory granules of neuroendocrine cells and neurons, as is a member of the granin family of proteins. It can be used both for immunohistochemical stains and as a serum marker 4.
Immunohistochemistry
Chromogranin A is use...
Article
Vitamin B complex
Historically, the vitamin B complex was the collective name given to a specific subset of the vitamins, known as the B vitamins. However the chemical structures of these compounds are structurally heterogeneous and they do not constitute a distinct biochemical group. They are all water soluble v...
Article
Ependymal cells
Ependymal cells are one of the four main types of glial cells, and themselves encompass three types of cells 1:
ependymocytes: line the ventricles of the brain and central canal of the spinal cord
tanycytes: line the floor of the third ventricle overlying the median eminence of the hypothalam...
Article
Tanycytes
Tanycytes are one of the three types of ependymal cells, themselves a type of glial cell. They are found lining the floor of the third ventricle overlying the median eminence of the hypothalamus 1.
It is believed that these specialized cells are involved in the feedback mechanisms on the ante...
Article
Pregnancy-associated plasma protein-A
Pregnancy-associated plasma protein-A (PAPP-A) is a protein found in the maternal circulation and is produced by the placenta. The PAPP-A gene has been assigned to human chromosome 9q33.1 and contains 22 exons 5. PAPP-A values tend to rise exponentially during pregnancy and the reference range d...
Article
Vascular invasion in lung cancer
Vascular invasion in lung cancer is one of the invasive patterns that can occur in lung cancer. Dependent on the publication, this could mean:
intratumoral vascular invasion (IVI)
microscopic vascular invasion (MVI)
lymphovascular invasion (LVI)
lymphatic permeation
arterial invasion
veno...
Article
Creatine kinase
Creatine kinase (CK), also known as creatine phosphokinase (CPK), is a key enzyme, for energy production in mitochondria and muscle tissues. It is important as a diagnostic assay in clinical practice, primarily because inflamed/injured muscle releases creatine kinase into the circulation 1.
Phy...
Article
Micrometastasis
Micrometastases are defined by the UICC TNM Classification of Malignant Tumors as conglomerations of tumor cells measuring between 0.2 mm and 2 mm in size. Clusters of cells sized less than 0.2 mm in maximal dimension are termed isolated tumor cells (ITCs). Tumor clusters measuring larger than 2...
Article
Vimentin
Vimentin is a fairly widespread cytoskeletal component encoding for intermediate filaments. It can be used as a target for immunohistochemistry to help characterize numerous tissues and tumors.
Article
Essential elements
The essential elements are chemical elements which are essential for optimal physical and mental well being, and required in bulk (cf. trace elements) quantities in a normal human diet. The elements are:
calcium
magnesium
phosphorus
potassium
sodium
Article
Neurofibromin
Neurofibromin is a protein coded for by the NF1 gene located on chromosome 17 (17q11.2). It is a multifunctional protein and is involved in the regulation of many cellular signaling pathways. In patients with a mutation of the NF1 gene, neurofibromin is defective and results in the clinical synd...