ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Articles  (5)
  • Cryofixation  (5)
  • Chemistry
  • Wiley-Blackwell  (5)
  • American Chemical Society
  • Annual Reviews
  • Beilstein-Institut
  • Blackwell Publishing Ltd
  • Gazi University, Faculty of Technology
  • The Royal Society
  • Wiley
  • 2015-2019
  • 2005-2009
  • 1990-1994  (5)
  • 1980-1984
  • 1970-1974
  • 1950-1954
  • 1940-1944
  • 2016
  • 1994  (2)
  • 1990  (3)
  • 1983
  • Natural Sciences in General  (5)
  • Sociology
Collection
  • Articles  (5)
Source
Keywords
Publisher
Years
  • 2015-2019
  • 2005-2009
  • 1990-1994  (5)
  • 1980-1984
  • 1970-1974
    • +
Year
Topic
  • 1
    Electronic Resource
    Electronic Resource
    Quantitative X-ray microanalysis of P, Ca, and S in the mucus secretory granules of the cryofixed frog palate epithelium (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Microscopy Research and Technique 28 (1994), S. 141-148 
    Details
    ISSN: 1059-910X
    Keywords: X-ray microanalysis ; Respiratory epithelium ; Secretory cells ; Cryofixation ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Natural Sciences in General
    Notes: In respiratory epithelium, the mucus is densely packed inside the secretory granules (SG) of secretory cells (SC) before being released by exocytosis in the airway lumen. We have previously shown that the frog palate is a representative model of respiratory epithelium and that rapid cryofixation is a very effective technique in preserving the integrity of the mucus SG. The concentration of phosphorus (P), sulphur (S), and calcium (Ca) were analysed inside the SG of the SC of frog palate after quick freezing, cryosubstitution, and embedding in Lowicryl resin at low temperature. The experiments were carried out using X-ray microanalysis conducted with energy dispersive spectrometry (EDS) at 100 kV. The quantitation was carried out using the continuum method with reference to Agar standards. The cryofixation permitted us to distinguish two types of SG depending on whether they were electron dense (serous cells) or electron-lucent (mucous cells). A significant (P 〈 0.001) difference in the S concentration was observed between the individual serous (239 ± 79 mmol.kg-1) and the mucous SG (161 ± 48 mmol.kg-1). No significant difference could be identified in the Ca concentration between the two SG phenotypes. In the serous SG, the P content was high (41 ± 17 mmol.kg-1) compared with the mucous SG where it was not measurable. The comparison of the three element concentrations in each type of secretory cells showed that significant differences in concentration of S and Ca concentration could be observed from one SC cell to another. A significant correlation (r = 0.76, P 〈 0.01) was observed between the S concentration and the topographical position of the SG inside the SC, the more proximal to the lumen, the higher the S concentration, suggesting that the maturation of the SG involves an increase in the protein content possibly due to a maturation process before the mucus exocytosis. Therefore, these results suggest that the elemental composition of granules varies according to the phenotype of the secretory cells and that changes in the S content from one SG to another or even inside the same cell may reflect a differential state in the functional activity of the secretory cells. © 1994 Wiley-Liss, Inc.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jemt.1070280205
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Improved ultrastructural preservation of rat ciliary body after high pressure freezing and freeze substitution: A perspective view based upon comparison with tissue processed according to a conventional protocol or by osmium tetroxide/microwave fixation (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Microscopy Research and Technique 29 (1994), S. 11-22 
    Details
    ISSN: 1059-910X
    Keywords: Cryofixation ; Electron microscopy ; Extracellular material ; Microtubules ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Natural Sciences in General
    Notes: Conventional fixation of the delicate, highly folded rat ciliary body and its iridial extension, as well as of vitreal structures, is associated with the induction of a number of artifacts, thus limiting the reliability of morphological interpretations. Improved ultrastructural preservation may be achieved by microwave heating in combination with osmium tetroxide fixation. This protocol, although simple and cheap, yields results, particularly with respect to the extracellular matrix compartment between inner and outer ciliary epithelial cells, which are not greatly inferior to those obtained by implementing the sophisticated high pressure freezing and freeze substitution technique. The latter affords good to very good ultrastructural preservation of epithelium and stromal components, such as blood vessels, neural elements, smooth muscle cells, fibrocytes, and free cells, up to a depth of 50-100 μm from the tissue surface. Its superiority over osmium tetroxide/microwave fixation is revealed in the cytoplasmic, intraorganellar, and vitreal matrix compartments, which incur no obvious losses. © 1994 Wiley-Liss, Inc.
    Additional Material: 22 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jemt.1070290103
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Morphology of rat exocrine pancreas prepared by anhydrous cryo-procedures (1990)
    New York, NY : Wiley-Blackwell
    Journal of Electron Microscopy Technique 14 (1990), S. 39-45 
    Details
    ISSN: 0741-0581
    Keywords: Exocrine pancreas ; Cryofixation ; Cryomicrotomy ; Freeze-drying ; Freeze-substitution ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Natural Sciences in General
    Notes: This paper describes and compares the morphology of a relatively complex tissue, the exocrine pancreas, prepared by state-of-the-art anhydrous cryoprocedures. Cryopreparative procedures are being used increasingly for a wide range of applications, for example, electron-probe x-ray microanalysis and immunocytochemical localization of antigenic molecules, because they preserve the composition of the specimen better than procedures involving aqueous media. Some doubts have remained concerning the morphology of cryosections and the precise identification of subcellular structures.We show that thin and sufficiently large cryosections of fresh biological tissues can be produced using commercially available hardware. The freeze-dried cryosections display high intrinsic contrast, are stable under the beam, and allow identification of intracellular fine structure.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jemt.1060140107
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Improved cryoprotection and freeze-substitution of embryonic quail retina: A tem study on ultrastructural preservation (1990)
    New York, NY : Wiley-Blackwell
    Journal of Electron Microscopy Technique 14 (1990), S. 348-356 
    Details
    ISSN: 0741-0581
    Keywords: Cryofixation ; Cryoprotectant ; Dimethylformamide ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Natural Sciences in General
    Notes: Conditions for cryofixation and freeze-substitution crucial to the ultrastructural preservation of embryonic quail retina were improved. As freeze-substitution makes gentle dehydration and chemical fixation of tissue possible, the suitability of different cryoprotectants were tested in the preceding cryofixation. Additionally, different conditions for chemical prefixation were studied. In cryofixation, all of the “classic” cryoprotectants caused more or less severe tissue destruction. Only dimethylformamide (DMF) and-with certain reservations-dimethylsulfoxide (DMSO) yielded improved structure preservation. Perfusion fixation with a mixture of formaldehyde/glutaraldehyde (FA/GA) was superior to GA alone. In comparison to conventional fixation and dehydration methods, freeze-substitution yielded better ultrastructural preservation of the embryos with fewer artifacts.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jemt.1060140410
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    A simple pneumatic device for plunge-freezing cells grown on electron microscopy grids (1990)
    New York, NY : Wiley-Blackwell
    Journal of Electron Microscopy Technique 16 (1990), S. 167-173 
    Details
    ISSN: 0741-0581
    Keywords: Plunge-freezing ; Cryofixation ; Freeze-substitution ; Monolayers ; Cultured cells ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Natural Sciences in General
    Notes: A detailed design for a simple and inexpensive variable-speed (1.0-5.8 m s-1) pneumatic plunge-freezing device is presented. Cultured cells, grown on Formvar-coated 75-mesh gold finder grids, are pneumatically driven into a stirring mixture of propane/isopentane (3:1) cooled by liquid nitrogen (LN2). Premature freezing of the sample in the cryogenic vapors above the cryogen is prevented by plunging through an entry tube into an insulating box, to which a partial vacuum is applied. The cryogenic vapors are drafted into the box at the level of the liquid cryogen by the vacuum, thereby preventing a layer of cold gas from collecting above the cryogen. To prevent the sample from thawing during transfer from the cryogen to the substitution medium, the box top is removed and compressed air is forced through a corrugated tube running the length of the box. The resulting boiling LN2 creates an atmosphere below -120°C in which the transfer can be accomplished.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jemt.1060160207
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...