ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 6 (1986), S. 128-135 
    ISSN: 0886-1544
    Keywords: motion analysis ; axonal transport ; cytoplasmic transport ; Brownian motion ; AVEC-DIC microscopy ; saltatory particle motion ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A survey study of organelle movements in a variety of cell types of plant and animal origin was made with the aid of video-enhanced contrast, differential interference contrast (AVEC-DIC) microscopy followed by fine analysis of the motile behavior of the individual organelles. We found that there exists besides Brownian motion a wide spectrum of active motions in cells, i.e. motion that is directionally biased through the expenditure of metabolic energy. The types of active motion seen range from a continuous motion (sometimes appearing as streaming) in plant cells and neurons to various types of less ordered and less well directed motion. We did not see any clear-cut qualitative difference between plant and animal cells or between systems presumed to be actin- and microtubule-based. A preliminary classification of the types of active motion is presented. The ongoing research activities, which aim at a more precise definition of the different types of motion by a set of quantitative parameters, are described, and the progress made so far is reported.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0170-2041
    Keywords: Steroids ; Titanium amides ; Ester enolates ; Dienone-benzene rearrangement ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Regioselective Reactions at the 17-Oxo Group of Androsta-1,4-dine-3,17-dione after in situ Protection with Titaniumtetrakis(dimethylamide)After in situ protection of androsta-1,4-diene-3,17-dione (1) with titaniumtetrakis(dimethylamide) (10) at -20°C to -30°C, the lithium enolates of methyl methoxyacetate (2a) and ethyl acetate (2b) react regio- and stereoselectively at the 17-position to give the 17-hydroxy-17α-pregnanes 12 and 6. Dehydration of 12 and 6 furnishes the 17(20)-olefins 13 and 14, intermediates for the synthesis of corticoids and gestagens. The reaction of 1 with 10 and 2a at -60°C gives byproducts of a dienone-benzene rearrangement of the A-ring. The reactions of 1 with 2a and 2b without titaniumtetrakis-(dimethylamide) (10) proceed regioselectively at the 3-position or nonregioselectively at the 3- and 17-positions, respectively.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...