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The third and final excretory organ that develops in a vertebrate embryo. In birds, reptiles, and mammals it replaces the mesonephros as the functional excretory organ and develops into the adult kidney.

[meta- + Greek nephros, kidney.]

met′a·neph′ric (-rĭk) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Physiology) relating to the metanephros
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
(3-11) These tumors have been published under the following names in the literature: leiomyomatous renal hamartomas, congenital mesoblastic nephroma in an adult, cystic hamartoma of renal pelvis, solitary multilocular cysts of the kidney, multilocular renal cyst with mullerian-like stroma, and adult metanephric stromal tumor.
Dysplastic changes are defined as altered metanephric differentiation during embryogenesis, leading to abnormal kidney.
Metanephric adenosarcoma in a young adult: morphologic, immunophenotypic, ultrastructural, and fluorescence in situ hybridization analyses: a case report and review of the literature.
The differential diagnosis for mesoblastic nephroma includes Wilms tumor, clear cell sarcoma, rhabdoid tumor, and metanephric stromal tumor.
Wilms tumor occurring in the kidney is thought to arise from aberrant differentiation of persistent metanephric mesenchyme.[9] Although the exact histogenesis of EWT is unclear, origin from persistent embryonic nests of primitive renal anlage is favored.
Even though the prototype tumor with papillary pattern is papillary RCC (Figure 2, A and B), a variety of renal neoplasms can have papillary architectures; these include clear cell (Figure 2, C), clear cell papillary (Figure 2, D), and rarely chromophobe (Figure 2, E), and mucinous tubular spindle cell RCCs, collecting duct carcinoma (Figure 2, F), as well as metanephric adenoma or metastatic carcinoma.
Gene expression in Wilms' tumour mimics the earliest committed stage in the metanephric mesenchymal-epithelial transition.
In B, urogenital system showing the syntopy of the organs, metanephric (MT), Ovary (O), uterine horn (Co), bladder (Bx), urethra (U) and external genitalia (Gex).
Single vaginal ectopic ureter of fetal metanephric duct origin, ipsilateral kidney agenesis, and ipsilateral rudimentary uterine horn of the bicornuate uterus.
The tumor consisted in tumor epithelial component (abortive tubules and glomeruli) surrounded by metanephric blastema and tumor immature spindled cell stroma without any anaplasia or emboli of tumor cells.
The excretory units composed of the glomeruli and the collecting system originate from the metanephric mesoderm and ureteric bud, respectively.
Redefining the in vivo origin of metanephric nephron progenitors enables generation of complex kidney structures from pluripotent stem cells.