(n.) The external skin or outer layer of an animal or plant, this being formed in an animal from the epiblast. See Illust. of Blastoderm.
Example Sentences:
(1) Here we report direct measurements of protein kinase C (PKC) activity in uninduced ectoderm, and in neuroectoderm shortly after induction by the involuting mesoderm, in Xenopus laevis embryos.
(2) The Notch locus in Drosophila encodes a transmembrane protein required for the determination of cell fate in ectodermal cells.
(3) The factor was tested on Triturus alpestris by the implantation method, and on isolated ectoderm of Xenopus laevis in solution.
(4) Evx-1 RNA is first detected shortly before the onset of gastrulation in a region of ectoderm containing cells that will soon be found in the primitive streak.
(5) Cells falling off from ectoderm were observed in normally developing gastrulae of the newt, Cynops pyrrhogaster, in light microscopic examination.
(6) Anhidrotic ectodermal dysplasia is characterized by an absence of seromucous glands in the oropharynx and tracheobronchial tree, making children with this disease prone to viral and bacterial respiratory infections.
(7) The positive reaction for keratin and vimentin confirmed the presence of ectodermal and mesodermal elements respectively in the tumor.
(8) Examination of the two types of tissue fragments revealed that IS-treated ICMs almost invariably retained viable endoderm cells whereas MS-isolated ectoderms did so only exceptionally.
(9) In the present study, ectodermal explants from Xenopus blastulae were shown to have high affinity binding sites for 125I-aFGF (Kd = 1.4 X 10(-10) M).
(10) Ectoderm from Cynops pyrrhogaster reacts like that of Ambystoma when exposed to LiCl, but like Triturus ectoderm it is insensitive to cyclic nucleotides.
(11) Several mouse mutants in the distal region of the mouse t-complex affecting blastocyst and embryonic ectoderm formation also map to this region.
(12) PTN mRNA was also strongly expressed in the basal layers of the tongue epithelium, which is the only epithelium and ectodermal derivative to express PTN mRNA, and this only after birth.
(13) These genes encode membrane proteins with epidermal growth factor repeats and are essential in the decision of an embryonic ectodermal cell to take on the fate of neuroblast or epidermoblast.
(14) We have found that competence of the ectoderm to respond to induction is lost at the same early neurula stage for all three marker genes.
(15) Multiple hamartoma syndrome, also known as Cowden's disease, is a rare genodermatosis with multiple organ system involvement affecting tissues derived from ectodermal, endodermal, and mesodermal tissue layers.
(16) From the right wing bud of stage 19 and 20 (HH) embryos the rim ectoderm was removed in four ways: all of the rim, the anterior third, the middle third (most of the A.E.R.
(17) During feather follicle formation, N-CAM was expressed in the dermal papilla and was closely apposed to the L-CAM-positive papillar ectoderm, while the dermal papilla showed no evidence of laminin or fibronectin.
(18) Initially each primordium forms a shallow depression in the ectodermal surface.
(19) From stage 110 on, a basement membrane differentiates beneath a one-cell thick subperipheral layer, which thus becomes the ectodermal basal layer, the prospective epidermal basal layer.
(20) CAT mRNA was observed in gut, mesenchyme cells and oral ectoderm in these embryos.
Embryo
Definition:
(n.) The first rudiments of an organism, whether animal or plant
(n.) The young of an animal in the womb, or more specifically, before its parts are developed and it becomes a fetus (see Fetus).
(n.) The germ of the plant, which is inclosed in the seed and which is developed by germination.
(a.) Pertaining to an embryo; rudimentary; undeveloped; as, an embryo bud.
Example Sentences:
(1) It was found that the skeletal muscle enzyme of the chick embryo is independent of the presence of creatine and consequently is another constitutive enzyme like the creatine kinase of the early embryonic chick heart.
(2) Since 1987, it has become possible to obtain immature ova from the living animal and to let them mature, fertilize and develop into embryos capable of transplantation outside the body.
(3) In X-irradiated litters, almost invariably, the incidence of anophthalmia was higher in exencephalic than in nonexencephalic embryos and the ratio of these incidences (relative risk) decreased toward 1 with increasing dose.
(4) The effects of hormonal promotion of T24-ras oncogene-transfected rat embryo fibroblasts (REF) were compared to cotransformation of these cells with adenovirus E1A and ras.
(5) Scatchard analyses of binding data obtained with synaptosomal preparations from 17-day-old embryos revealed two T3 binding sites.
(6) In the stage 24 chick embryo, a paced increase in heart rate reduces stroke volume, presumably by rate-dependent decrease in passive filling.
(7) From the biochemical markers in follicular fluid, cyclic adenosine monophosphate has a distinct predictive value in regard to pregnancy in in vitro fertilization-embryo transfer cycles.
(8) Implantation of the mouse embryo involves the invasion of the secondary trophoblast giant cells of the ectoplacental cone (EPC) into the uterine decidua.
(9) They suggest that an endogenous retinoid could contribute to positional information in the early Xenopus embryo.
(10) A cytogenetic and anatomopathologic study of an embryo of 24 mm crown-rump length showing pure triploidy (69,XXY) is reported.
(11) The in vivo approach consisted of interspecies grafting between quail and chick embryos.
(12) Here we report direct measurements of protein kinase C (PKC) activity in uninduced ectoderm, and in neuroectoderm shortly after induction by the involuting mesoderm, in Xenopus laevis embryos.
(13) Results obtained from cumulative labeling and pulse-labeling and chase experiments with cells from late gastrulae, yolk plug-stage embryos, and neurulae showed that the 30S RNA is an intermediate in rRNA processing and is derived from 40S pre-rRNA and processed to 28S rRNA.
(14) During that time they have repeatedly demonstrated the likely existence of signalling molecules or morphogens that control the pattern of development in the embryo.
(15) Ernst Reissner studied the formation of the inner ear initially using the embryos of fowls, then the embryos of mammals, mainly cows and pigs, and to a less extent the embryos of man.
(16) The objective of this study was to examine the effects of different culture media used for maturation of bovine oocytes on in vitro embryo development following in vitro fertilization.
(17) By 3 d in the chick embryo, the first neurons detected by antibodies to Ng-CAM are located in the ventral neural tube; these precursors of motor neurons emit well-stained fibers to the periphery.
(18) None of the factors tested was found to have a statistically significant effect on embryo yield.
(19) The embryo stages were assessed visually and some were investigated histologically.
(20) Ninety semen specimens were analysed for use in an IVF-embryo transfer (ET) programme.