(n.) The structureless, protoplasmic tissue of the embryo; the primitive basis of an organ yet unformed, from which it grows.
Example Sentences:
(1) They are capable of synthesis and accumulation of glycogen and responsible for its transfer to sites of more intense metabolism (growth, bud, blastema).
(2) Blastemas implanted with 2 dorsal root ganglia and simultaneously denervated 14 days after amputation exhibited control levels of cell cycle activity 6 days later, as measured by 3H-thymidine pulse labeling.
(3) A search for specific proteins involved in newt limb regeneration, using monoclonal antibodies against forelimb blastemas, led to the detection of an antigen in the regenerate epithelium.
(4) Between different tumours, heterogeneity in the degree of epithelial differentiation in the blastema was found.
(5) After amputation, limbs of both early and late stages form a regenerative blastema and support lens formation from the outer cornea.
(6) More difficult are clear therapeutic recommendations for the very rare forms of endocrinically active genital tumors which stem from sex cords or which are composed of different components of the complex ovarian blastema.
(7) By 15 days, a dense accumulation of blastema cells is present beneath the apical cap, and these cells are preferentially oriented in a circumferential direction.
(8) Not all cells of the adult newt blastema are randomly distributed and actively progressing through the cell cycle.
(9) Thus, it appears that denervation of medium-bud-stage limb blastemas promotes the lengthening of G1 and premature exiting of cells from the cycle into the G0-1 phase.
(10) Computer-assisted morphometric analysis showed only minor differences between proximal tubular cells from 18-day embryos and tubular cells from 7-day cultures of blastema taken from 11-day embryos.
(11) In the absence of skin, epidermal wound healing failed to occur and blastemas could not develop.
(12) At the contact between the ureter and the mesonephretic blastema, the cells of the primary ureter have special characteristics: existence of an abundant "coat", numerous "villous processes" and a dense network of fibres of collagen.
(13) Serial angiograms and tissue biopsies documented the transition from nodular renal blastema to Wilms' tumor.
(14) After amputation, NvKII mRNA is expressed both in proximal and distal blastemas, although at higher levels distally, indicating that this keratin is regeneration associated.
(15) Since others have shown that denervation at the time of amputation blocks subsequent mitosis in internal stump tissues yet allows normal levels of DNA synthesis for eight days, we conclude that X-irradiation and denervation prevent cell division in potential blastema cells by different mechanisms.
(16) In a study of 71 female foetuses, gonadal blastema was observed at 1.5 cm crown rump length (CRL).
(17) Furthermore, staining with three fucose-binding lectins revealed that the linkage between terminal alpha-fucose residues to the constituent oligosaccharide chains varied between epithelial cells, blastema and stroma.
(18) However, in differentiation phase blastemas, laminin immunoreactivity was concentrated in specific locations.
(19) The fasciculata cells are the direct continuation of the subcapsular blastema.
(20) These results indicate that the limb tissues of the early stage limbs contain non-neural inductive factors at a low level and that after limb amputation and blastema formation the level of these factors becomes high enough to promote lens formation from implanted cornea, even after denervation.
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.