(n.) The process of invagination, in embryonic development, by which a gastrula is formed.
Example Sentences:
(1) Birthdates of neurons were obtained from autoradiograms of animals receiving tritiated thymidine from gastrulation through 1 month after metamorphosis.
(2) 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.
(3) The embryos incubated in vitro at the from blastula stage are characterized by the sharp activation of protein synthesis and the vegetal-animal gradient of protein synthesis, as well as in the control embryos; such embryos gastrulate and proceed to primary differentiation.
(4) Thus, the area with separated HL, which is restricted to the region of the PMC released at the stage of PMC ingression, spreads almost entirely throughout the area of the indenting vegetal plate at gastrulation.
(5) On the basis of hystological studies a description of fission and gastrulation in Microsomacanthus paramicrosoma (gasowska, 1931) is given.
(6) This contrasts with embryos ventralized by UV-irradiation and suggests that XBMP-4-induced ventralization occurs after the onset of gastrulation.
(7) Several lines of experimental evidence indicate that contact with the animal pole locus, or "target" region, is crucial for the change in phenotype of the SMCs: (1) the phenotypic change can be induced precociously by bringing the animal pole region within reach of the tip of the archenteron early in gastrulation.
(8) Gastrulation is accompanied by a sharp increase in the AChE activity which was most pronounced in anterior hypoblast.
(9) In the present study, it was found that cytotactin is first present in the gastrulating chicken embryo.
(10) Experiments are described that examine the state of organisation of the presumptive mesoderm and ectoderm of the Xenopus embryo at stages up to the onset of gastrulation.
(11) As a result, there is a loss of the 'compacted' epithelial surface of the blastula, an inability to close a wounded surface and defective gastrulation.
(12) (d) Tenascin blocks cell adhesion to FN in vitro and gastrulation in vivo.
(13) In contrast, in vitro activity of mannosylphosphoryldolichol synthase, another enzyme in the pathway of N-linked glycosylation, was maximal in membranes from egg and embryos in the early stages of development and declined prior to gastrulation.
(14) As an immediate consequence of neural induction during gastrulation, some neuroectodermal cells acquire the ability to develop a number of specific neuronal and astroglial features, without requiring subsequent chordamesodermal cues.
(15) After gastrulation additional novel non-oogenetic proteins were synthesized for most stages examined.
(16) An analysis of changes in cell shape during the initial phase of gastrulation indicates that there is a stage-dependent shift from cells being columnar to having their apices skewed toward the vegetal plate and an increase in the proportion of cells having basal processes during gastrulation.
(17) In view of the hypocalcaemic properties of calcitonin and the importance of calcium ions in cell aggregation, this phenomenon has been attributed to an alteration in cell adhesion which results in faulty cell migration during gastrulation with consequent abnormalities of the prechordal region of the archenteron roof and the overlying neural plate.
(18) Microtubule distribution was examined in whole mounts of Drosophila embryos from the cellularization of the syncytial blastoderm (stage 6) to the completion of the gastrulation (stage 7) by fluorescence microscopy.
(19) These changes in the dynamic properties of the lipid probe HEDAF during gastrulation suggest that the lipid phase of the plasma membrane of these ectodermal cells undergo structural changes.
(20) In Lytechinus, the late appearing histone, H1g, begins to be synthesized at gastrulation.
Organogenesis
Definition:
(n.) The origin and development of organs in animals and plants.
(n.) The germ history of the organs and systems of organs, -- a branch of morphogeny.
Example Sentences:
(1) This attack can take place during organogenesis, during early differentiation of neural anlagen after neural tube closure or during biochemical differentiation of the brain.
(2) Separation and recombination experiments, employing a variety of tissue configurations in organ culture, were performed to determine the extent to which the epithelium of the maxillary process influences the viability of the underlying mesenchyme during organogenesis.
(3) The histochemical study of the LDH in the Trout embryo during the early organogenesis shows a specific localization in notochord cells, in mesodermic cells of the terminal knob and in some prosencephalic neuroblasts.
(4) Further research is necessary to investigate possible teratogenic effects that might occur if the spirochete reaches the fetus during the period of organogenesis.
(5) In the present study the distribution of various sugar residues in the cells of the male gonad during postnatal organogenesis was examined employing eight lectin-horseradish peroxidase conjugates (BS-I, ConA, DBA, PNA, RCA-I, SBA, UEA-I, WGA) on paraffin-embedded testicular tissue.
(6) Renal dysplasia was associated with extrarenal malformations in 2 of our cases and we therefore believe that the significance of the dysplasia lies rather in the period of the insult during organogenesis than in the obstruction.
(7) In the present study we investigated (1) the developmental pattern of expression of the chicken insulin gene in the pancreas; (2) the expression of the insulin gene in three nonpancreatic tissues, liver, brain, and lower limb, during chicken development; and (3) the expression of the insulin gene at prepancreatic stages and during chicken embryo organogenesis.
(8) However, the stress associated with maternally toxic doses can be expected to result in associated, often transient, fetal abnormalities that may not be the result of deviant organogenesis.
(9) Insulin and insulin-like growth factor I (IGF I) play an important part in these events in the later stages of embryogenesis, when organogenesis is completed.
(10) We briefly review evidence from in vitro models that supports a role for the extracellular matrix in two essential steps of organogenesis: the establishment of appropriate three-dimensional cell-to-cell relationships, and the determination of a correct cell polarity.
(11) The experiments indicate that D-mannose may be employed in model systems with rodents for precisely timed interruptions of organogenesis in vivo.
(12) Estradiol-17 beta (E2) and 17 alpha-ethinyl estradiol-17 beta (EE) were compared in terms of their relative capacities to alter growth and developmental patterns of cultured whole embryos during the early stages of organogenesis.
(13) However, we established an enhanced level of [14C]acetate incorporation at the time of extensive gene activation during gastrulation as well as some quantitative differences in the pattern of acetylation during gastrula and organogenesis.
(14) It describes the entire gestation period including the period of organogenesis.
(15) Lysosomes participate in the following processes during the course of embryonal organogenesis: 1. destruction of cells of transient embryonal organs; 2. destruction and demolition of whole cells during the course of normal embryonal development; covering with a membrane and lysis of inferior cellular organelles; 5. lysis with consecutive assimilation of cytoplasmic inclusion; lysis of secretory products.
(16) The expression of vimentin, cytokeratins (CKs) and neurofilament (NF) proteins was analysed (using monoclonal antibodies) in the mouse inner ear at the otocyst stage (13th gestational day), when organogenesis was largely completed (16th gestational day) and at birth (21st gestational day).
(17) We conclude: 1) ANP is present in the fetus shortly after the completion of organogenesis; 2) 16 K ANP is the principal intracardiac species in the fetus and the adult; and 3) the existence of ANP soon after cardiac development suggests a possible role for ANP in fetal blood pressure and sodium and water homeostasis.
(18) Morphogenesis was retarded during the early organogenesis stages, but only a slight delay was seen in the treated embryo on day 12.
(19) Congenital rubella syndrome occurred in 2 newborn infected at the organogenesis period (4-8 weeks).
(20) We have used monoclonal antibodies to study the changes in the expression of four kidney antigens during organogenesis in the sheep.