Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • 1990-1994  (1)
  • 1970-1974  (2)
  • 1945-1949
  • 1930-1934
  • Pomatoceros triqueter  (2)
  • 1H, 13C, 77Se n.m.r. sprectra  (1)
Materialart
Erscheinungszeitraum
  • 1990-1994  (1)
  • 1970-1974  (2)
  • 1945-1949
  • 1930-1934
Jahr
  • 1
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 113 (1971), S. 388-395 
    ISSN: 1432-0878
    Schlagwort(e): Pomatoceros triqueter ; Egg investments ; Fertilization reaction ; Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The ultrastructure of unfertilized and fertilized egg investments ofPomatoceros triqueter is described. A characteristic feature is the presence of a hitherto unrecorded additional investment layer, inserted between the chorion and the “outer border layer”, which is referred to as the intermediate layer. The fertilization reaction consists of the release of cortical granule material into the perivitelline “space”, and the severing of the microvillous cytosome to “outer border layer” connections, thus allowing an increase in the width of the perivitelline “space”. More ridged corrugations are found on the outer surface of the investments in the fertilized as compared with the unfertilized condition.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 123 (1972), S. 486-495 
    ISSN: 1432-0878
    Schlagwort(e): Pomatoceros triqueter ; Cytokinesis ; Surface folding ; New surface membrane ; Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The first cleavage division of Pomatoceros triqueter eggs is described. Time-lapse microcinematographic and electron microscopic studies revealed that, prior to division, the plasma membrane was folded into pleats. These were not present after division. This fact pointed to an unfolding of the plasma membrane which enabled it to cover the increased surface area resulting from cleavage. It is suggested that the pre-cleavage folds are derived from the membranes of the cortical granules, which continue releasing their contents into the perivitelline region following fertilization and first division. Filamentous material in the form of a band was present subjacent to the plasma membrane in the region of the furrow. The individual filaments of this band measure 5 to 7 nm in cross section, the dimensions being similar to those described for other kinds of dividing cells.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    Digitale Medien
    Digitale Medien
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 1693-1698 
    ISSN: 0044-2313
    Schlagwort(e): Tris(trimethylsilyl)methaneselenenyl halides ; Tris(trimethylsilyl)methaneselenyl chalcogenides ; 1H, 13C, 77Se n.m.r. sprectra ; crystal structure ; Chemistry ; Inorganic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Tris(trimethylsilyl)methaneselenenyl Halides and Chalcogenides.Ditrisyldiselenide (1) (trisyl = TSi = (Me3Si)3C) reacts with SOCl2, Br2 and I2 to provide trisylselenenyl halides TSiSeX (2: X = Cl; 3: X = Br, 4: X = I). Insertion of S and Se into the Se—Se bond of 1 to yield (TSiSe)2Sn (5: n = 1; 6: n = 2) and (TSiSe)2Sen (7: n = 1; 8: n = 2) was catalysed by iodine. 5 was isolated in pure state and examined by X-ray diffraction. Triselenide 7 can be cleaved by I2 in CS2 to give 4 and Se2I2 (9). From 2 with Me3SiCN and Me3SiNCS, the new selenenyl pseudohalides TSiSeCN (10) and TSiSeSCN (11) were prepared. The compounds were characterised by 1H, 13C- and 77Se n.m.r. spectra.
    Notizen: Ditrisyldiselenid (1) (Trisyl  -  Tsi  -  (Me3Si)3C—) reagiert mit SOCl2, Br2 und I2 zu Trisylselenenylhalogeniden TSiSeX (2: X = Cl; 3: X = Br, 4: X = I). Die Einschiebung von Schwefel und Selen in die Se—Se-Bindung von 1 zu (TSiSe)2 Sn (5: n = 1; 6: n = 2) bzw. (TSiSe)2Sen (7: n = 1; 8: n = 2) läßt sich mit Iod katalysieren. 5 wurde in reiner Form isoliert und durch Röntgenstrukturanalyse untersucht. Das Triselenid 7 wird durch Iod in CS2 zu 4 und Se2I2 (9) gespalten. Aus 2 lassen sich mit Me3SiCN bzw. Me3SiNCS das Trisylselenocyanat TSiSeCN (10) bzw. Trisylselenenylthiocyanat TSiSeSCN (11) gewinnen. 1H, 13C- und 77Se-NMR Spektren von 1 - 11 sind im Einklang mit den Strukturvorschlägen.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...