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Reticular Veins
Telangiectasias (), also known as spider veins, are small dilated blood vessels that can occur near the surface of the skin or mucous membranes, measuring between 0.5 and 1 millimeter in diameter. These dilated blood vessels can develop anywhere on the body, but are commonly seen on the face around the nose, cheeks and chin. Dilated blood vessels can also develop on the legs, although when they occur on the legs, they often have underlying venous reflux or "hidden varicose veins" (see Venous hypertension section below). When found on the legs, they are found specifically on the upper thigh, below the knee joint and around the ankles. Many patients with spider veins seek the assistance of physicians who specialize in vein care or peripheral vascular disease. These physicians are called vascular surgeons or phlebologists. More recently, interventional radiologists have started treating venous problems. Some telangiectasias are due to developmental abnormalities that can close ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal-cell Carcinoma
Basal-cell carcinoma (BCC), also known as basal-cell cancer, basalioma, or rodent ulcer, is the most common type of skin cancer. It often appears as a painless, raised area of skin, which may be shiny with small blood vessels running over it. It may also present as a raised area with ulceration. Basal-cell cancer grows slowly and can damage the tissue around it, but it is unlikely to spread to distant areas or result in death. Risk factors include exposure to ultraviolet light (UV), having lighter skin, radiation therapy, long-term exposure to arsenic, and poor immune-system function. Exposure to UV light during childhood is particularly harmful. Tanning beds have become another common source of ultraviolet radiation. Diagnosis often depends on skin examination, confirmed by tissue biopsy. Whether sunscreen affects the risk of basal-cell cancer remains unclear. Treatment is typically by surgical removal. This can be by simple excision if the cancer is small; otherwise, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blanch (medical)
When skin is blanched, it takes on a whitish appearance as blood flow to the region is prevented. This occurs during and is the basis of the physiologic test known as diascopy. Blanching of the fingers is also one of the most clinically evident signs of Raynaud's phenomenon. Blanching is prevented in gangrene as the red blood corpuscles are extravasated and impart red color to the gangrenous part. See also * Diascopy *Pallor Pallor is a pale color of the skin that can be caused by illness, emotional shock or stress, stimulant use, or anemia, and is the result of a reduced amount of oxyhaemoglobin and may also be visible as pallor of the conjunctivae of the eye ... References Dermatologic terminology {{dermatology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naevus Flammeus
A port-wine stain (''nevus flammeus'') is a discoloration of the human skin caused by a vascular anomaly (a capillary malformation in the skin). They are so named for their coloration, which is similar in color to port wine, a fortified wine, fortified red wine from Portugal. A port-wine stain is a capillary malformation, birthmark, seen at birth. Port-wine stains persist throughout life. The area of skin affected grows in proportion to general growth. Port-wine stains occur most often on the face but can appear anywhere on the body, particularly on the neck, upper trunk, arms and legs. Early stains are usually flat and pink in appearance. As the child matures, the color may deepen to a dark red or purplish color. In adulthood, thickening of the lesion or the development of small lumps may occur. Port-wine stains may be part of a syndrome such as Sturge–Weber syndrome or Klippel–Trénaunay–Weber syndrome. Types Nevus flammeus may be divided as follows:James, William; Ber ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Repair
DNA repair is a collection of processes by which a cell (biology), cell identifies and corrects damage to the DNA molecules that encode its genome. A weakened capacity for DNA repair is a risk factor for the development of cancer. DNA is constantly modified in Cell (biology), cells, by internal metabolism, metabolic by-products, and by external ionizing radiation, ultraviolet light, and medicines, resulting in spontaneous DNA damage involving tens of thousands of individual molecular lesions per cell per day. DNA modifications can also be programmed. Molecular lesions can cause structural damage to the DNA molecule, and can alter or eliminate the cell's ability for Transcription (biology), transcription and gene expression. Other lesions may induce potentially harmful mutations in the cell's genome, which affect the survival of its daughter cells following mitosis. Consequently, DNA repair as part of the DNA damage response (DDR) is constantly active. When normal repair proce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Null Allele
A null allele is a nonfunctional allele (a variant of a gene) caused by a genetic mutation. Such mutations can cause a complete lack of production of the associated gene product or a product that does not function properly; in either case, the allele may be considered nonfunctional. A null allele cannot be distinguished from deletion of the entire locus solely from phenotypic observation. A mutant allele that produces no RNA transcript is called an RNA null (shown by Northern blotting or by DNA sequencing of a deletion allele), and one that produces no protein is called a protein null (shown by Western blotting). A genetic null or amorphic allele has the same phenotype when homozygous as when heterozygous with a deficiency that disrupts the locus in question. A genetic null allele may be both a protein null and an RNA null, but may also express normal levels of a gene product that is nonfunctional due to mutation. Null alleles can have lethal effects depending on the importa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bloom Syndrome
Bloom syndrome (often abbreviated as BS in literature) is a rare autosomal recessive genetic disorder characterized by short stature, predisposition to the development of cancer, and genomic instability. BS is caused by mutations in the '' BLM'' gene which is a member of the RecQ DNA helicase family. Mutations in genes encoding other members of this family, namely '' WRN'' and '' RECQL4'', are associated with the clinical entities Werner syndrome and Rothmund–Thomson syndrome, respectively. More broadly, Bloom syndrome is a member of a class of clinical entities that are characterized by chromosomal instability, genomic instability, or both, and cancer predisposition. Cells from a person with Bloom syndrome exhibit a striking genomic instability that includes excessive crossovers between homologous chromosomes and sister chromatid exchanges (SCEs). New York dermatologist Dr. David Bloom discovered and first described the condition in 1954. Bloom syndrome has also appeared in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congenital
A birth defect is an abnormal condition that is present at childbirth, birth, regardless of its cause. Birth defects may result in disability, disabilities that may be physical disability, physical, intellectual disability, intellectual, or developmental disability, developmental. The disabilities can range from mild to severe. Birth defects are divided into two main types: structural disorders in which problems are seen with the shape of a body part and functional disorders in which problems exist with how a body part works. Functional disorders include metabolic disorder, metabolic and degenerative disease, degenerative disorders. Some birth defects include both structural and functional disorders. Birth defects may result from genetic disorder, genetic or chromosome abnormality, chromosomal disorders, exposure to certain medications or chemicals, or certain vertically transmitted infection, infections during pregnancy. Risk factors include folate deficiency, alcohol drink, d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sclerodactyly
Sclerodactyly is a localized thickening and tightness of the skin of the fingers or toes that yields a characteristic claw-like appearance and spindle shape of the affected digits, and renders them immobile or of limited mobility. The thickened, discolored patches of skin are called morphea, and may involve connective tissue below the skin, as well as muscle and other tissues. Sclerodactyly is often preceded by months or even years by Raynaud's phenomenon when it is part of systemic scleroderma. The term "sclerodactyly" comes . It is generally associated with systemic scleroderma and mixed connective tissue disease, and auto-immune disorders. Sclerodactyly is one component of the limited cutaneous form of systemic sclerosis (lcSSc), also known as CREST syndrome (CREST is an acronym that stands for calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia.) Sclerodactyly is also one component of Huriez Syndrome, along with palmoplantar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esophageal Motility Disorder
An esophageal motility disorder (EMD) is any medical disorder resulting from dysfunction of the coordinated movement of esophagus, which causes dysphagia (i.e. difficulty in swallowing, regurgitation of food). Primary motility disorders are: * Achalasia * Diffuse esophageal spasm * Nutcracker esophagus * Hypertensive lower esophageal sphincter An esophageal motility disorder can also be secondary to other diseases. For example, it may be a result of CREST syndrome, referring to the five main features: calcinosis, Raynaud syndrome, esophageal dysmotility, sclerodactyly and telangiectasia.Winterbauer RH (1964). "Multiple telangiectasia, Raynaud's phenomenon, sclerodactyly, and subcutaneous calcinosis: a syndrome mimicking hereditary hemorrhagic telangiectasia". Bulletin of the Johns Hopkins Hospital 114: 31–83. . Symptoms The most common symptom of esophageal motility disorders is dysphagia. Compared to causes of mechanical obstruction, which usually coincide with diffi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raynaud's Phenomenon
Raynaud syndrome, also known as Raynaud's phenomenon, is a medical condition in which the spasm of small arteries causes episodes of reduced blood flow to end arterioles. Typically the fingers, and, less commonly, the toes, are involved. Rarely, the nose, ears, nipples, or lips are affected. The episodes classically result in the affected part turning white and then blue. Often, numbness or pain occurs. As blood flow returns, the area turns red and burns. The episodes typically last minutes but can last several hours. The condition is named after the physician Auguste Gabriel Maurice Raynaud, who first described it in his doctoral thesis in 1862. Episodes are typically triggered by cold or emotional stress. Primary Raynaud's is idiopathic (spontaneous and of unknown cause) and not correlated with another disease. Secondary Raynaud's is diagnosed given the presence of an underlying condition and is associated with an older age of onset. In comparison to primary Raynaud's, ep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcinosis
Calcinosis is the formation of calcium deposits in any soft tissue. It is a rare condition that has many different causes. These range from infection and injury to systemic diseases like kidney failure. Types Dystrophic calcification The most common type of calcinosis is dystrophic calcification. This type of calcification can occur as a response to any soft tissue damage, including that involved in implantation of medical devices. Metastatic calcification Metastatic calcification involves a systemic calcium excess imbalance, which can be caused by hypercalcemia, kidney failure, milk-alkali syndrome, lack or excess of other minerals, or other causes. Tumoral calcinosis The cause of the rare condition of tumoral calcinosis is not entirely understood. It is generally characterized by large, globular calcifications near joints. See also * Calcification * Calcinosis cutis * Dermatomyositis * Fahr's syndrome * Hyperphosphatemia * Primrose syndrome * Scleroderma Scleroderma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
