yolk sac

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Related to Yolk sac tumor: embryonal carcinoma

yolk sac

n.
A membranous sac attached to the embryo and enclosing the yolk in egg-laying vertebrates. In humans and other placental mammals, it functions as the circulatory system for the embryo before internal circulation begins.
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.

yolk sac

n
1. (Zoology) the membranous sac that is attached to the ventral surface of the embryos of birds, reptiles, and some fishes and contains yolk
2. (Zoology) the corresponding part in the embryo of mammals, which contains no yolk
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

yolk′ sac`


n.
an extraembryonic membrane that encloses the yolk of eggs.
[1860–65]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

yolk sac

A sac attached to the gut of an embryo that encloses the yolk in bony fish, sharks, reptiles, mammals, and birds. In most mammals, the yolk sac functions as part of the embryo's circulatory system before the placenta develops.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.yolk sac - membranous structure that functions as the circulatory system in mammalian embryos until the heart becomes functionalyolk sac - membranous structure that functions as the circulatory system in mammalian embryos until the heart becomes functional
sac - a structure resembling a bag in an animal
2.yolk sac - membranous structure enclosing the yolk of eggs in birds, reptiles, marsupials, and some fishes; circulates nutrients to the developing embryo
sac - a structure resembling a bag in an animal
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
The distinction between HYST, hepatocellular carcinoma, and HCO can also be problematic, especially since yolk sac tumor normally expresses AFP and Glypican 3.
We will also review recent nomenclature proposals concerning the yolk sac tumor group and, in benign germ cell tumors, we will only consider new and relevant advances in paraneoplastic manifestations of mature cystic teratoma and on the origin of gliomatosis peritonei.
tumor 01 03.3% Total 30 100% Table 4: Distribution based on Histopathological Report Histopathology Percentage Report Epithelial tumors Serous Benign 6 20 Borderline 0 0.00 Malignant 3 10.00 Mucinous 0.00 Benign 7 23.33 Borderline 1 3.33 Malignant 1 3.33 Endometrioid 0.00 Benign 0 0.00 Malignant 0 0.00 Germ cell tumor 0.00 Yolk sac tumor 1 3.33 Mature cystic teratoma 0 0.00 Dysgerminoma 3.33 Mixed Germ cell tumor 3.33 Sex cord stromal tumor 0.00 Fibroma 3.33 Metastatic adenocarcinoma 3.33 Benign Cyst 10.00 Mixed Serous Mucinous Cyst adenoma 3.33 No.
(12) Yolk sac tumor is positive for alpha-feto protein (AFP).
Although yolk sac tumors and benign teratomas are common in early childhood, these 2 histologic types appear in combination with other histologic types in older ages (12,13).
This creation and maintenance of the pluripotent state prior to and during migration may explain the histologies specific to Type I GCTs, namely teratoma (TER) and yolk sac tumor (YST) [24].
Reports state hepatoid carcinoma as the representative type along with GCED, tubular adenocarcinoma, papillary adenocarcinoma, poorly differentiated adenocarcinoma, and yolk sac tumor [1-9].
Primary yolk sac tumor of endometrium: Report of two cases and review of literature.
The use of cytokeratin 7 and EMA in differentiating ovarian yolk sac tumors from endometrioid and clear cell carcinomas.
The most common type of testicular tumors in children is yolk sac tumor (54-66%).
cases (242) % 1 Surface epithelial tumors 158 100 A Serous tumors 115 72.78 47.52 Benign 88 55.70 36.36 Borderline 2 1.27 0.83 Malignant 25 15.82 10.33 B Mucinous tumors 36 22.78 14.88 Benign 27 17.09 11.16 Borderline 4 2.53 1.65 Malignant 5 3.16 2.07 C Endometroid tumor 1 0.63 0.41 D Brenner tumor 6 3.80 2.48 2 Sex cord-stromal tumor 18 100 7.44 Granulosa cell tumor 10 55.56 4.13 Fibroma 3 16.67 1.24 Thecoma fibroma 4 22.22 1.65 Androblastoma 1 5.55 0.41 3 Germ cell tumors 58 100 23.96 Dysgerminoma 6 10.34 2.48 Yolk sac tumor 3 5.17 1.24 Mature cystic teratoma 43 74.14 17.77 Immature teratoma 2 3.45 0.82 Struma ovarii 3 5.17 1.24 Mixed germ cell tumor 1 1.72 0.41 4 Metastatic tumor 8 100 3.31
Nonseminomas are developed from mature reproductive cells, usually seen in the third decade of life and histologically they represent a mixed type of tumors, such as embryonal cell carcinoma, choriocarcinoma, yolk sac tumor and teratoma.