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Related to blastocysts: Blastocystis hominis


A modified blastula characteristic of placental mammals.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



blastodermic sac, a stage in the development of mammal embryos, including humans, that arises as a result of cleavage of the fertilized ovum. The blastocyst is a hollow sac. An aggregate of cells—a node, analogous to the blastula of other animals—is found on one side of it. The outer wall of the blastocyst forms the trophoblast.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Chromosome mosaicism in day 3 aneuploid embryos that develop to morphologically normal blastocysts in vitro.
After being implanted into pseudo-pregnant rats, the complemented blastocysts matured into normal fetuses.
Corresponding author of the study, Masumi Hirabayashi said that their study confirms that interspecific blastocyst complementation is a viable method for kidney generation.
On day 5 of in vitro cultivation, resulting blastocysts were evaluated morphologically.[4] Initially, they were assigned a numeric score (between 1 and 6) based on their degree of expansion, and hatching status: (1) early blastocyst (i.e., where the blastocoel formed less than half of the volume of the embryo); (2) blastocyst, (where the blastocoel formed more than half of the volume of the embryo); (3) full blastocyst, (where the blastocoel completely filled the embryo); (4) expanded blastocyst, (where the blastocoel volume was larger than that of the early embryo, and the zona had begun to thin); (5) hatching blastocyst, (where the TE had begun to herniate though the zona); and (6) hatched blastocyst, (where the blastocyst had completely escaped from the zona).
Effect of follicular fluid supplementation during in vitro maturation on total cell number in bovine blastocysts produced in vitro.
Correlations between diameter and cell numbers, development stages and quality of bovine blastocysts
The SYBER Green PCR kit (Qiagen, Germany) was used to extract RNA from all 80 vitrified and non-vitrified 2-cell and blastocyst embryos.
The data obtained from values of osmolality and cell numbers of the blastocysts were analyzed with Tukey-Kramer post hoc tests for multiple comparisons following ANOVA.
Three months later the patient underwent a frozen IVF cycle, involving the transfer of two blastocyst stage (Day 5) embryos.