1. SYN: metamorphosis. 2. A change of one tissue into another, as cartilage into bone. 3. In metals, a change in phase and physical properties in the solid state caused by heat treatment. 4. In microbial genetics, transfer of genetic information between bacteria by means of “naked” intracellular DNA fragments derived from bacterial donor cells and incorporated into a competent recipient cell. [L. trans-formo, pp. -atus, to transform]
- cavernous t. of portal vein replacement of the portal vein by a number of collateral channels, a consequence of thrombosis.
- cell t. morphologic and physiologic changes including loss of contact inhibition resulting from infection of an animal cell by an oncogenic virus.
- Haldane t. the multiplication of inspired oxygen concentration by the ratio of expired to inspired nitrogen concentrations in the calculation of oxygen consumption or respiratory quotient by the open circuit method.
- Lobry de Bruyn -van Ekenstein t. the conversion of glucose to fructose and mannose in dilute alkali by enolization adjacent to the carbonyl group to form an enediol, a reaction analogous to certain biochemical transformations.
- logit t. a method of linearizing dose-response curves for radioimmunoassay techniques; i.e., logit B (bound)/Bo (initial binding) = log (B/Bo/1 − B/Bo).
- lymphocyte t. the t. into large, blastlike forms (immunoblasts) that occurs when lymphocytes are exposed to histoincompatible antigens (mixed lymphocyte culture) or mitogens. SEE ALSO: mixed lymphocyte culture test.
- nodular t. of the liver a rare condition in which nodules of hyperplastic hepatocytes develop without fibrosis or general loss of lobular architecture. SYN: nodular regenerative hyperplasia.

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trans·for·ma·tion .tran(t)s-fər-'mā-shən, -fȯr- n
1) an act, process, or instance of transforming or being transformed see MALIGNANT TRANSFORMATION
2 a) genetic modification of a bacterium by incorporation of free DNA from another ruptured bacterial cell compare TRANSDUCTION (2)
b) genetic modification of a cell by the uptake and incorporation of exogenous DNA

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trans·for·ma·tion (trans″for-maґshən) [trans- + formation] 1. change of form or structure; conversion from one form to another. 2. in oncology, the change that a normal cell undergoes as it becomes malignant. 3. in eukaryotes, the conversion of normal cells to malignant cells in cell culture. 4. bacterial t.

Medical dictionary. 2011.

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  • transformation — [ trɑ̃sfɔrmasjɔ̃ ] n. f. • 1375; lat. transformatio 1 ♦ Action de transformer, opération par laquelle on transforme. ⇒ conversion. La transformation des matières premières. Industrie de transformation. « un de ces théoriciens qui ont rêvé [...]… …   Encyclopédie Universelle

  • Transformation — (root transform ) may refer to:Transformation is also referred to as a turn.In science: * Transformation (geometry), in mathematics, as a general term applies to mathematical functions. ** Data transformation (statistics) in statistics. *… …   Wikipedia

  • transformation — is the process by which transactions that are open at, or after, the record date/election transfer date are cancelled and/or replaced by new transactions in accordance with the terms of the reorganisation. Euroclear Clearing and Settlement… …   Financial and business terms

  • Transformation — (lateinisch die Umformung) bezeichnet allgemein die Veränderung der Gestalt, Form oder Struktur. Der Begriff wird in einer Vielzahl von Themengebieten verwendet: Konvertierung (Informatik) in der Informatik die Überführung von Daten in ein… …   Deutsch Wikipedia

  • transformation — Transformation. s. f. v. Changement d une forme en une autre. La transformation des metaux. la transformation fabuleuse de Protée. les Poëtes Grecs sont pleins de transformations fabuleuses …   Dictionnaire de l'Académie française

  • Transformation — Trans for*ma tion, n. [L. transformatio: cf. transformation.] The act of transforming, or the state of being transformed; change of form or condition. Specifically: [1913 Webster] (a) (Biol.) Any change in an organism which alters its general… …   The Collaborative International Dictionary of English

  • transformation — (n.) c.1400, from O.Fr. transformation and directly from L. transformationem (nom. transformatio), noun of action from pp. stem of transformare (see TRANSFORM (Cf. transform)) …   Etymology dictionary

  • transformation — transformation. См. трансформация. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • Transformation — (lat., »Umgestaltung«), in der Mathematik zunächst soviel wie Substitution (s. d.), dann aber auch jedes Verfahren, durch das aus gegebenen Figuren neue Figuren von andrer Lage und andrer Gestalt abgeleitet werden. Eine T. in diesem Sinn erhält… …   Meyers Großes Konversations-Lexikon

  • Transformation — Transformation, gewöhnlich so viel wie Substitution (s.d.). Zwischen Scharen von Transformationen und von Substitutionen besteht jedoch der Unterschied, daß bei ersteren die Parameter stetig veränderliche Größen sind, während sie bei letzteren… …   Lexikon der gesamten Technik

  • Transformation — (lat.), Umbildung; transformieren, umformen, umbilden …   Kleines Konversations-Lexikon

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