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
  • 2000-2004  (3)
  • 1930-1934  (1)
Materialart
Erscheinungszeitraum
Jahr
  • 1
    Digitale Medien
    Digitale Medien
    s.l. : American Chemical Society
    Journal of the American Chemical Society 55 (1933), S. 3277-3279 
    ISSN: 1520-5126
    Quelle: ACS Legacy Archives
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    ISSN: 1365-3040
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Aerenchyma formation in roots of maize (Zea mays L.) involves programmed death of cortical cells that is promoted by exogenous ethylene (1 µL L−1) or by endogenous ethylene produced in response to external oxygen shortage (3%, v/v). In this study, evidence that degeneration of the cell wall accompanies apoptotic-like changes previously observed in the cytoplasm and nucleus (Gunawardena et al. Planta 212, 205–214, 2001), has been sought by examining de-esterified pectins (revealed by monoclonal antibody JIM 5), and esterified pectins (revealed by monoclonal antibody JIM 7). In controls, de-esterified wall pectins were found at the vertices of triangular junctions between cortical cells (untreated roots). Esterified pectins in control roots were present in the three walls bounding triangular cell-to-cell junctions. After treatment with 3% oxygen or 1 µL L−1 ethylene, this pattern was lost but walls surrounding aerenchyma gas spaces became strongly stained. The results showed that cell wall changes commenced within 0·5 d and evidently were initiated by ethylene in parallel with cytoplasmic and nucleoplasmic events associated with classic intracellular processes of programmed cell death.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Polar biology 23 (2000), S. 352-356 
    ISSN: 1432-2056
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract A method to study bacterioplankton community structure in Antarctic freshwater lake samples is described. Small samples (between 300 and 1000 ml) taken in remote field locations were used for crude DNA extraction, followed by PCR amplification of 16S rRNA gene fragments using group-specific primers. The amplification products of the PCR reaction were then separated using denaturing gradient gel electrophoresis to produce a profile of the bacterioplankton community. Whilst the technique is only semi-quantitative, it readily differentiated communities from lakes of different trophic status and from vertical profiles within different lake types. The method offers a sensitive tool for screening and monitoring Antarctic freshwater environments as a precursor and adjunct to more detailed studies.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Microbial ecology 40 (2000), S. 57-63 
    ISSN: 1432-184X
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The influence of substrate concentration on plasmid transfer frequency in the rhizosphere was investigated using a physical model employing a hollow fiber membrane instead of a real root. The absolute number of transconjugants produced increased with increasing substrate (glucose) concentration, but the plasmid transfer frequency decreased exponentially with increasing substrate concentration from 4.4 × 10-3 at 90 μg ml-1 glucose to 1.35 × 10-5 at 3600 μg ml-1 glucose. These results were found to be heavily dependant on donor to recipient ratio and distribution of strains, but independent of initial donor and recipient inoculum density and regime. These observations also show that plasmid transfer frequency is reduced at high substrate concentrations, which suggests that plasmid transfer is either stimulated when growth limiting nutrient is scarce or inhibited when it is abundant.
    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...