(1) Light and electron microscope observation of the mesoderm of the yold sac membrane indicate that individual presumptive precursors of the definitive-line are present as early as 2 days of incubation and give rise to sequestered populations of immature erythroblasts within sinusoids during the period of 2.5-6 days incubation.
(2) A pathway of the yold protein and factors determining its routing in the oocyte have been studied.
(3) W8 killed fowl and turkey embryos when injected into the yold sacs of embryonating eggs.
(4) Greatly elongated forms were commonly found in cultures and yold sac membranes after 5 to 7 days of growth but were only rarely seen in human lung.
(5) Lysolecithin-treated microsomal sediment and supernatant galactosyltransferase was inactivated by oleoyllysophosphatidic acid but not by palmitoyllysophosphatidic acid or egg yold lysophosphatidic acid.
(6) The excess 15N atom% (15N') was established in the crude protein, in the nitrogen from the TCE soluble and TCE precipitable fractions and in the N from 17 amino acids of the egg yold and egg white.
(7) The hematic yold precursor--vitellogenin--has been identified immunochemically in the serum of estrogenized females of the nest Triturus cristatus by employing an antiserum prepared against yold proteins.
Yolk
Definition:
(n.) The yellow part of an egg; the vitellus.
(n.) An oily secretion which naturally covers the wool of sheep.
Example Sentences:
(1) Whether hen's egg yolk can be used as a sperm motility stimulant in the treatment of such conditions as asthenospermia and oligospermia is subjected for further study.
(2) 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.
(3) The wall of the yolk sac thickens as a result of this infolding and the densely packed capillaries.
(4) When foods such as dairy products contain large numbers of egg yolk-negative strains of S. aureus, the PPSA agar has the advantage over egg yolk containing media such as Baird-Parker agar that fewer suspect colonies have to be confirmed.
(5) In lipid extracts of yolk, more than 90% of the radioactivity was as unchanged cholecalciferol and 5% as 25-hydroxycholecalciferol.
(6) This study provides evidence for a maternal yolk factor associated with increased tolerance and resistance of larvae to copper.
(7) Both genes are expressed in the fetal liver, gut, and visceral endoderm of the yolk sac and are repressed shortly after birth in the liver and gut.
(8) After clusters of pigmented epithelial cells have rested immobile in the yolk sac of Blennius pholis for 2-4 days (Trinkaus, '88), their constituent cells transform into mesenchymal, dendritic melanocytes.
(9) The patient, a 28-year-old woman, in her ninth week of pregnancy, was operated on for stage Ia, mixed germ cell tumor (grade 3 immature teratoma + yolk sac tumor) of AFP decreased to the normal level.
(10) Fe2+ and L-ascorbic acid induced oxidation of cholesterol was investigated in liposomes of egg yolk phosphatidylcholine (PC).
(11) Cadmium, anti-visceral yolk sac antibody (AVYS) and trypan blue all inhibited pinocytosis in a concentration-dependent fashion when added to the culture medium, although at low concentrations trypan blue was slightly stimulatory.
(12) Although small amounts of AFP are synthesized by sharks in the liver, the greatest site of synthesis is actually the stomach, with smaller amounts synthesized in the intestinal mucosa; no synthesis was observed in the shark yolk sac.
(13) In three experiments with semen samples from a single individual capacitated at 4 degrees C for 1, 2 or 3 days in TEST-Yolk buffer we obtained 33, 30 and 34 sperm karyotypes respectively.
(14) A stem cell line has been obtained with cell culture, having a germ cell character and a yolk sac configuration.
(15) We postulate that the apposition of trophotaenial epithelium to the internal ovarian epithelium constitutes a placental association equivalent to a noninvasive, epithelioform of an inverted yolk sac placenta.
(16) The histological characteristics and the presence of laminin in the stroma suggested that the malignant tumors belonged to the category of yolk sac tumors.
(17) PLA2-II was over ten times more potent than PLA2-I, although its lipolytic activity toward egg-yolk was even slightly weaker (73%) than that of PLA2-I.
(18) The majority of testicular germ cell tumors in adults are accompanied by neoplastic intratubular germ cells; these cells were uniformly absent in ten pure yolk sac tumors (endodermal sinus tumors) of the testicle in children studied morphologically and immunohistochemically.
(19) The beta-globin gene remained inactive at the fetal stage, whereas the normal A gamma-globin gene was expressed beyond the embryonic (yolk sac) stage into the fetal stage of development and then became inactive in adult erythroid cells.
(20) The yolk spheres, which were free of precipitates, gave the characteristic signal of the nitrogen K-edge.