Từ điển y khoa
Thuật ngữ y khoa chuẩn hóa theo MeSH, ICD-11, SNOMED CT.
62,341 terms indexed
A hereditary autosomal dominant form of chondrocalcinosis that is caused by mutations in the ANKH gene. OMIM: 118600
Polymorphic cells that form cartilage.
A heterogeneous group of bone dysplasias, the common character of which is stippling of the epiphyses in infancy. The group includes a severe autosomal recessive form (CHONDRODYSPLASIA PUNCTATA, RHIZOMELIC), an autosomal dominant form (Conradi-Hunermann syndrome), and a milder X-linked form. Metabolic defects associated with impaired peroxisomes are present only in the rhizomelic form.
An autosomal recessive form of CHONDRODYSPLASIA PUNCTATA characterized by defective plasmalogen biosynthesis and impaired peroxisomes. Patients have shortened proximal limbs and severely disturbed endochondral bone formation. The metabolic defects associated with the impaired peroxisomes are present only in the rhizomelic form of chondrodysplasia punctata. (From Scriver et al, Metabolic Basis of Inherited Disease, 6th ed, p1497)
The formation of cartilage. This process is directed by CHONDROCYTES which continually divide and lay down matrix during development. It is sometimes a precursor to OSTEOGENESIS.
A mucopolysaccharide constituent of chondrin. (Grant and Hackh's Chemical Dictionary, 5th ed)
An enzyme that catalyzes the eliminative degradation of polysaccharides containing 1,4-beta-D-hexosaminyl and 1,3-beta-D-glucuronosyl or 1,3-alpha-L-iduronosyl linkages to disaccharides containing 4-deoxy-beta-D-gluc-4-enuronosyl groups. (Enzyme Nomenclature, 1992)
Enzymes which catalyze the elimination of delta-4,5-D-glucuronate residues from polysaccharides containing 1,4-beta-hexosaminyl and 1,3-beta-D-glucuronosyl or 1,3-alpha-L-iduronosyl linkages thereby bringing about depolymerization. EC 4.2.2.4 acts on chondroitin sulfate A and C as well as on dermatan sulfate and slowly on hyaluronate. EC 4.2.2.5 acts on chondroitin sulfate A and C.
Proteoglycans consisting of proteins linked to one or more CHONDROITIN SULFATE-containing oligosaccharide chains.
Derivatives of chondroitin which have a sulfate moiety esterified to the galactosamine moiety of chondroitin. Chondroitin sulfate A, or chondroitin 4-sulfate, and chondroitin sulfate C, or chondroitin 6-sulfate, have the sulfate esterified in the 4- and 6-positions, respectively. Chondroitin sulfate B (beta heparin; DERMATAN SULFATE) is a misnomer and this compound is not a true chondroitin sulfate.
Enzymes which catalyze the elimination of glucuronate residues from chondroitin A, B, and C or which catalyze the hydrolysis of sulfate groups of the 2-acetamido-2-deoxy-D-galactose 6-sulfate units of chondroitin sulfate. EC 4.2.2.-.
A group of enzymes that catalyze the hydrolysis of various sulfate bonds of chondroitin sulfate. EC 3.1.6.-.
A benign neoplasm derived from mesodermal cells that form cartilage. It may remain within the substance of a cartilage or bone (true chondroma or enchondroma) or may develop on the surface of a cartilage (ecchondroma or ecchondrosis). (Dorland, 27th ed; Stedman, 25th ed)
A degeneration of the ARTICULAR CARTILAGE of the PATELLA, caused by a decrease in sulfated MUCOPOLYSACCHARIDES in the ground substance. When accompanied by pain, it is sometimes considered part of or confused with PATELLOFEMORAL PAIN SYNDROME.
Multiple formation of chondromas. (Dorland, 27th ed)
Rare, benign, chronic, progressive metaplasia in which cartilage is formed in the synovial membranes of joints, tendon sheaths, or bursae. Some of the metaplastic foci can become detached producing loose bodies. When the loose bodies undergo secondary calcification, the condition is called synovial osteochondromatosis.
A slowly growing malignant neoplasm derived from cartilage cells, occurring most frequently in pelvic bones or near the ends of long bones, in middle-aged and old people. Most chondrosarcomas arise de novo, but some may develop in a preexisting benign cartilaginous lesion or in patients with ENCHONDROMATOSIS. (Stedman, 25th ed)
A rare malignant soft tissue neoplasm that originates from CHONDROBLASTS. It is most common in male middle-aged and elderly individuals and often presents as deep lesions in soft tissue of the extremities. Malignancy is low, but recurrence and METASTASIS can occur many years after the initial diagnosis. Histologically, the tumors consist of a mixture of cellular and myxoid stromal components. Can be caused by somatic chromosomal translocations resulting in fusions between the NR4A3 and EWSR1 genes, and NR4A3 and TAF15 genes. OMIM: 612237
A rare aggressive variant of chondrosarcoma, characterized by a biphasic histologic pattern of small compact cells intermixed with islands of cartilaginous matrix. Mesenchymal chondrosarcomas have a predilection for flat bones; long tubular bones are rarely affected. They tend to occur in the younger age group and are highly metastatic. (DeVita Jr et al., Cancer: Principles and Practice of Oncology, 3d ed, p1456)
A genus of RED ALGAE, in the family Gigartinaceae. The species Chondrus crispus is a source of CARRAGEENAN.
A branch of the facial (7th cranial) nerve which passes through the middle ear and continues through the petrotympanic fissure. The chorda tympani nerve carries taste sensation from the anterior two-thirds of the tongue and conveys parasympathetic efferents to the salivary glands.
The tendinous cords that connect each cusp of the two atrioventricular HEART VALVES to appropriate PAPILLARY MUSCLES in the HEART VENTRICLES, preventing the valves from reversing themselves when the ventricles contract.
Phylum in the domain Eukarya, comprised of animals either with fully developed backbones (VERTEBRATES), or those with notochords only during some developmental stage (CHORDATA, NONVERTEBRATE).
A portion of the animal phylum Chordata comprised of the subphyla CEPHALOCHORDATA; UROCHORDATA, and HYPEROTRETI, but not including the Vertebrata (VERTEBRATES). It includes nonvertebrate animals having a NOTOCHORD during some developmental stage.
A malignant tumor arising from the embryonic remains of the notochord. It is also called chordocarcinoma, chordoepithelioma, and notochordoma. (Dorland, 27th ed)
A subfamily of the family POXVIRIDAE, containing eight genera comprising all the vertebrate poxviruses.
Involuntary, forcible, rapid, jerky movements that may be subtle or become confluent, markedly altering normal patterns of movement. Hypotonia and pendular reflexes are often associated. Conditions which feature recurrent or persistent episodes of chorea as a primary manifestation of disease are referred to as CHOREATIC DISORDERS. Chorea is also a frequent manifestation of BASAL GANGLIA DISEASES.
A rare movement disorder developed during PREGNANCY, characterized by involuntary jerky motion (CHOREA) and inability to maintain stable position of body parts (ATHETOSIS). RHEUMATIC FEVER and collagen vascular disorders are frequently associated with this disease. Chorea may vary from mild to severe and occurs in approximately 1 per 2,000 to 3,000 pregnancies. (From Md Med J 1997 Sep;46(8):436-9)
associated with mutation of thyroid transcription factor 1 gene NKX2
mutation in GCH1
A highly vascularized extra-embryonic membrane, formed by the fusion of the CHORION and the ALLANTOIS. It is mostly found in BIRDS and REPTILES. It serves as a model for studying tumor or cell biology, such as angiogenesis and TISSUE TRANSPLANTATION.
INFLAMMATION of the placental membranes (CHORION; AMNION) and connected tissues such as fetal BLOOD VESSELS and UMBILICAL CORD. It is often associated with intrauterine ascending infections during PREGNANCY.
A malignant metastatic form of trophoblastic tumors. Unlike the HYDATIDIFORM MOLE, choriocarcinoma contains no CHORIONIC VILLI but rather sheets of undifferentiated cytotrophoblasts and syncytiotrophoblasts (TROPHOBLASTS). It is characterized by the large amounts of CHORIONIC GONADOTROPIN produced. Tissue origins can be determined by DNA analyses: placental (fetal) origin or non-placental origin (CHORIOCARCINOMA, NON-GESTATIONAL).
A highly malignant CHORIOCARCINOMA derived from the non-placental origin such as the totipotent cells in the TESTIS, the OVARY, and the PINEAL GLAND. It produces high levels of CHORIONIC GONADOTROPIN and can metastasize widely through the bloodstream to the lungs, brain, liver, bone, and other viscera by the time of diagnosis.
The outermost extra-embryonic membrane surrounding the developing embryo. In REPTILES and BIRDS, it adheres to the shell and allows exchange of gases between the egg and its environment. In MAMMALS, the chorion evolves into the fetal contribution of the PLACENTA.
A gonadotropic glycoprotein hormone produced primarily by the PLACENTA. Similar to the pituitary LUTEINIZING HORMONE in structure and function, chorionic gonadotropin is involved in maintaining the CORPUS LUTEUM during pregnancy. CG consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is virtually identical to the alpha subunits of the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity (CHORIONIC GONADOTROPIN, BETA SUBUNIT, HUMAN).
The beta subunit of human CHORIONIC GONADOTROPIN. Its structure is similar to the beta subunit of LUTEINIZING HORMONE, except for the additional 30 amino acids at the carboxy end with the associated carbohydrate residues. HCG-beta is used as a diagnostic marker for early detection of pregnancy, spontaneous abortion (ABORTION, SPONTANEOUS); ECTOPIC PREGNANCY; HYDATIDIFORM MOLE; CHORIOCARCINOMA; or DOWN SYNDROME.
Threadlike vascular projections of the chorion. Chorionic villi may be free or embedded within the DECIDUA forming the site for exchange of substances between fetal and maternal blood (PLACENTA).
A method for diagnosis of fetal diseases by sampling the cells of the placental chorionic villi for DNA analysis, presence of bacteria, concentration of metabolites, etc. The advantage over amniocentesis is that the procedure can be carried out in the first trimester.