placentation


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placentation

 [plas″en-ta´shun]
the series of events following implantation of the embryo and leading to development of the placenta.

plac·en·ta·tion

(plas'en-tā'shŭn),
The structural organization and mode of attachment of fetal to maternal tissues in the formation of the placenta. Types of placentation are defined under placenta.

placentation

/pla·cen·ta·tion/ (pla″sen-ta´shun) the series of events following implantation of the embryo and leading to development of the placenta.

placentation

(plăs′ən-tā′shən)
n.
a. Formation of a placenta in the uterus.
b. The type or structure of a placenta.

placentation

Obstetrics The formation of the placenta in the uterus; the process by which a placenta grows and develops in the uterus. See Extrachorial placentation.

plac·en·ta·tion

(plas'en-tā'shŭn)
The structural organization and mode of attachment of fetal to maternal tissues in the formation of the placenta.

placentation

the arrangement of PLACENTAS (2) in the plant ovary, which can be classified into several categories including:
  1. (a) apical, at the ovary apex,
  2. (b) basal, at the ovary base,
  3. (c) parietal, on the ovary wall,
  4. (d) free-central, on a column growing up from the ovary base.

placentation

1. the series of events following implantation of the embryo and leading to development of the placenta.
2. the nature of the implantation. See also placenta.

adventitial placentation
developmental of additional areas outside the normal areas, e.g. intercotyledonary in cattle.
cotyledonary placentation
the areas of placentation are limited to caruncles, approximately circular masses scattered over the placenta. Characteristic of the cow, ewe and goat doe.
diffuse placentation
the whole of the surface of the chorion is placental.
intercotyledonary placentation
abnormal placental attachments between the cotyledons, in cows.
zonal placentation
only some zones of the placenta have a vascular area involved in placentation. Characteristic of the bitch and the queen.
Enlarge picture
Zonary placenta of carnivores. By permission from Sack W, Wensing CJG, Dyce KM, Textbook of Veterinary Anatomy, Saunders, 2002
References in periodicals archive ?
Thus, each MRI sign shows a different performance in diagnosing MAP, in our study as well as in others, and some signs are more frequently observed in MAP cases than in normal placentation (Fig.
2] influence placentation and decrease placental vascularization.
pylori infection, as mentioned above, is associated to several pathologies during pregnancy, such as PE and RCIU that are mainly characterized by and abnormal placentation that leads to spontaneous abortion cases.
These days play a vital role in the reproductive biology of rabbits since from day 13 to day 18 is the placentation period whereas from day18 to 28 is the fetal growth stage during successful pregnancy.
Finally, because of their central role in trophoblast invasion into the uterine endometrium, which is essential for proper hemochorial placentation, the volume density and the absolute volumes of TGC and glycogen cells were determined.
Many ADAMTS have been detected in human placenta and uterine tissue, which suggests that these proteinases may have important roles in human placentation and implantation.
Abnormalities in uterine blood flow, abnormal placentation and subsequent rates of abruption have been theorized as potential causes (D'Souza & Arulkumaran, 2013).
It can be also speculated that serum IMA levels from women with ectopic pregnancy may be detected to be higher than those with normal placentation in first trimester by a hypoxic environment and reperfusion oxidative damage.
High-risk pregnancies should continue to be identified; however, identification often occurs after placentation.
They cover its history, complications, placentation, pathophysiology, the use of color injection and digital angiography, determining the natural history, clinical effects, diagnosis, maternal nutrition, the role of the cervix, acute twin-to-twin transfusion syndrome, feto-fetal transfusion syndrome in triplets, therapy, neonatal outcomes, monitoring, and ethical issues.
The role of matrix proteins, cytokins and angiogenesis factors of uterine placental complex in regulation of implantation and placentation," Obstetrics and gynecology [Akusherstvo i ginekologiya], in Russian, Vol.