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
  • 1
    Electronic Resource
    Electronic Resource
    Assay of the concentration and stable isotope enrichment of short-chain fatty acids by gas chromatography/mass spectrometry (1995)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 30 (1995), S. 747-754 
    Details
    ISSN: 1076-5174
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Isotope dilution gas chromatographic mass spectrometric assays were developed for the concentration of shortchain fatty acids and of lactate in plasma. The assays involve spiking the samples with 2H- and/or 13-C-labeled internal standards and direct derivatization with 2,4-difluoroaniline, using 1,3-dicyclohexylcarbodiimide as a coupling agent. The assay can be used to determine the isotopic enrichment or mass isotopomer distribution of the fatty acids and of lactate. Blanks by ubiquitous formate, acetate and lactate are minimized by the one-step derivatization procedure without deproteinization, using reagents dissolved in hydrocarbons. The assays were applied to experiments conducted in live dogs, pigs and monkeys, and in perfused rat livers. These techniques, in conjunction with appropriate stable isotope models, can be used to study carbohydrate fermentation in humans, ruminants and non-ruminant mammals.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jms.1190300514
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Surface structure of human mucin using X-ray photoelectron spectroscopy (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Biospectroscopy 4 (1998), S. 257-266 
    Details
    ISSN: 1075-4261
    Keywords: X-ray photoelectron spectroscopy ; surface analysis ; MUC1 mucin ; structure ; glycosylation ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: X-ray photoelectron spectroscopy (XPS) is a surface sensitive analytical technique that measures the binding energy of electrons in atoms and molecules on the surface of a material. XPS was used to determine the distribution of the oligosaccharide side chains in the glycoprotein, MUC1 mucin. Low-resolution XPS spectra provided elemental composition of MUC1 mucin (fully glycosylated), mucin polypeptide (nonglycosylated), and carbohydrates found in mucin. The nitrogen content of MUC1 mucin was determined to be intermediate between the mucin polypeptide and the carbohydrates. Assuming a uniform distribution of carbohydrate on MUC1 mucin, the average thickness of the carbohydrate layer was calculated to be 4.9 nm using the low-resolution N 1s signals. High-resolution XPS spectra give detailed information about the chemical bonding of the surface molecules. Calculations based on the high-resolution O 1s spectra showed a carbohydrate thickness of 6.6 nm. These experimentally determined values agree reasonably well with an estimated 5 nm of carbohydrate thickness from a simple model which assume that the core protein is a rodlike molecule approximately 5 nm in diameter. Although the carbohydrate coating on the MUC1 mucin appears to be thick enough to cover the core protein entirely, fully glycosylated breast milk MUC1 mucin is susceptible to proteolytic digestion without removal of any oligosaccharide side chain, suggesting areas of exposed core protein. A possible explanation is that the oligosaccharide side chains may form patches of carbohydrate along the core protein with regions of exposed core protein. © 1998 John Wiley & Sons, Inc. Biospectroscopy 4: 257-266, 1998
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 3
    Electronic Resource
    Electronic Resource
    Cancer grading by Fourier transform infrared spectroscopy (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Biospectroscopy 4 (1998), S. 37-46 
    Details
    ISSN: 1075-4261
    Keywords: FTIR ; cancer prognosis ; cancer grade ; tissue spectroscopy ; lymphoma ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Physics
    Notes: Thirty-nine freeze-dried tissue samples from 17 lymphoid tumors (nine malignant non-Hodgkin's lymphomas) were studied by Fourier transform infrared (FTIR) spectroscopy. The absorbance ratio A1121/A1020 increased, along with the emergence of an absorbance pulse at 1121 cm-1, with increasing clinicopathological grade of malignant lymphoma. An increasing A1121/A1020 ratio from benign to malignant is evident in literature spectra from several different tissues; however, the present study is the first to comment on this effect and to propose it as an index of the cellular RNA/DNA ratio after subtraction of overlapping absorbances, if present, due to collagen or glycogen. Absorbance attributable to collagen increased with lymphoma grade and was greater in benign inflammatory tumors than in low-grade lymphomas. The A1121/A1020 trend observed here may form the basis of a universal cancer-grading parameter to assist with cancer treatment decisions and may also be useful in the analysis of cellular growth perturbation induced by drugs or other therapies. Our spectral findings may potentially be applied to cell clusters and discrete areas of tumor tissue sections using the FTIR microscope, allowing correlation with morphology and a high degree of spatial resolution. © 1998 John Wiley & Sons, Inc. Biospectroscopy 4: 37-46, 1998
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 4
    Electronic Resource
    Electronic Resource
    Separation of calixarenes with a chemically bonded C60 silica stationary phase in microcolumn liquid chromatography (1996)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 19 (1996), S. 475-477 
    Details
    ISSN: 0935-6304
    Keywords: Microcolumn liquid chromatography ; C60 bonded phase ; Calixarenes ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jhrc.1240190814
    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...