Transcription (biologie)En biologie moléculaire, la transcription est la première étape de l'expression génique basée sur l'ADN, au cours de laquelle un segment particulier d'ADN est « copié » en ARN par une enzyme appelée ARN polymérase. Chez les eucaryotes, la transcription se déroule dans le noyau des cellules. Certains types d'ARN appélés « ARN non codants » n'ont pas vocation à être traduits en protéines et peuvent jouer un rôle régulateur ou structurel (par exemple les ARN ribosomiques).
Artificial kidneyArtificial kidney is often a synonym for hemodialysis, but may also refer to the other renal replacement therapies (with exclusion of kidney transplantation) that are in use and/or in development. This article deals mainly with bioengineered kidneys/bioartificial kidneys that are grown from renal cell lines/renal tissue. The first successful artificial kidney was developed by Willem Kolff in the Netherlands during the early 1940s: Kolff was the first to construct a working dialyzer in 1943.
CiliopathieA ciliopathy is any genetic disorder that affects the cellular cilia or the cilia anchoring structures, the basal bodies, or ciliary function. Primary cilia are important in guiding the process of development, so abnormal ciliary function while an embryo is developing can lead to a set of malformations that can occur regardless of the particular genetic problem. The similarity of the clinical features of these developmental disorders means that they form a recognizable cluster of syndromes, loosely attributed to abnormal ciliary function and hence called ciliopathies.
Dual (category theory)In , a branch of mathematics, duality is a correspondence between the properties of a category C and the dual properties of the Cop. Given a statement regarding the category C, by interchanging the source and target of each morphism as well as interchanging the order of composing two morphisms, a corresponding dual statement is obtained regarding the opposite category Cop. Duality, as such, is the assertion that truth is invariant under this operation on statements.
Branchial cleft cystA branchial cleft cyst or simply branchial cyst is a cyst as a swelling in the upper part of neck anterior to sternocleidomastoid. It can, but does not necessarily, have an opening to the skin surface, called a fistula. The cause is usually a developmental abnormality arising in the early prenatal period, typically failure of obliteration of the second, third, and fourth branchial cleft, i.e. failure of fusion of the second branchial arches and epicardial ridge in lower part of the neck.
CalcitonineLa calcitonine est une hormone peptidique de 32 acides aminés. La majeure partie de calcitonine est produite chez l'être humain par les cellules parafolliculaires (aussi nommées cellules C) de la thyroïde et chez plusieurs autres espèces animales par les corps ultimobranchiaux. La calcitonine participe au métabolisme phosphocalcique en s'opposant aux effets de l'hormone parathyroïdienne (PTH) du moins pour la calcémie. C'est une hormone hypocalcémiante et hypophosphorémiante.
