GLORIA

GEOMAR Library Ocean Research Information Access

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
  • 1990-1994  (3)
  • 1
    Electronic Resource
    Electronic Resource
    Decreased resistance toN,N-dimethylated anthracyclines in multidrug-resistant Friend erythroleukemia cells (1993)
    Springer
    Cancer chemotherapy and pharmacology 31 (1993), S. 301-307 
    Details
    ISSN: 1432-0843
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Doxorubicin-resistant Friend erythroleukemia cells, line F4–6 ADM2R, were selected by exposure of wild-type F4-6 cells to doxorubicin concentrations of up to 1 μg/ml. In these cells, increased expression of multidrug resistance (MDR) genes was demonstrated by Northern blot analysis. The growth-inhibitory effect of doxorubicin, daunorubicin,N,N-dimethyldoxorubicin,N,N-dimethyldaunorubicin, morpholinodoxorubicin, and pyrromycin was comparatively investigated in resistant and wild-type cells. The doxorubicin-resistant F4-6 cells showed approx. 200-fold resistance to doxorubicin and about 100-fold resistance to daunorubicin with respect to the drug-sensitive counterpart. A dramatic decrease in resistance was observed for theN,N-dimethylated derivatives of doxorubicin and daunorubicin as well as for theN,N-dimethylated natural anthracycline pyrromycin and for morpholinodoxorubicin. Uptake studies using [14C]-daunorubicin and [14C]-N,N-dimethyldaunorubicin in resistant F4-6 cells showed a decreased accumulation of daunorubicin but no significant reduction inN,N-dimethyldaunorubicin accumulation as compared with the wild-type cells. Treatment with verapamil led to increased intracellular levels of daunorubicin in resistant cells, whereas an excess ofN,N-dimethyldaunorubicin did not have this effect. Thus, the decreased resistance of the doxorubicin-resistant F4-6 cells to theN-alkylated anthracyclines may at least in part be due to a reduced affinity of these compounds for the efflux pump. The results indicate that the dimethylation of the amino group of the anthracycline sugar moiety and its incorporation within a morpholinyl ring may overcome MDR by similar mechanisms.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00685675
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Low molecular weight subunits associated with the cytochrome b 6 f complexes from spinach and Chlamydomonas reinhardtii (1993)
    Springer
    Photosynthesis research 38 (1993), S. 73-81 
    Details
    ISSN: 1573-5079
    Keywords: cytochrome f ; cytochrome b 6 ; thylakoid membranes ; low molecular weight subunits ; petG
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cytochrome b 6 f complexes, prepared from spinach and Chlamydomonas thylakoids, have been examined for their content of low molecular weight subunits. The spinach complex contains two prominent low molecular weight subunits of 3.7 and 4.1 kD while a single prominent component of 4.5 kD was present in the Chlamydomonas complex. An estimation of the relative stoichiometry of these subunits suggests several are present at levels approximating one copy per cytochrome complex. The low molecular weight subunits were purified by reversed phase HPLC and N-terminal sequences obtained. Both the spinach and Chlamydomonas cytochrome complexes contain a subunit that is identified as the previously characterized petG gene product (4.8 kD in spinach and 4.1 kD in Chlamydomonas). A second subunit (3.8 kD in spinach and 3.7 kD in Chlamydomonas) appears to be homologous in the two complexes and is likely to be a nuclear gene product. The possible presence of other low molecular weight subunits in these complexes is also considered.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00015063
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Modellgestütztes Messen in chemischen ReaktorenVortrag von H. Schuler auf dem Jahrestreffen der Verfahrens-Ingenieure, 3. bis 5. Okt. 1990 in Stuttgart. (1991)
    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 63 (1991), S. 189-203 
    Details
    ISSN: 0009-286X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Model-aided measurement in chemical reactors. Some reaction-specific variables of chemical reactors can be determined only with difficulty, sometime only with analytical measurements which are corrupted by time lags. In contrast, the approach tries to determine these variables indirectly and without time delay from easily measured variables like temperatures, pressures, flows. These sensor signals are processed together with reactor models to provide the characteristic reaction variables. This contribution discusses the applications of model-based measuring techniques to chemical reactors. The systems are applied to operator assistence, process diagnosis, and reactor control. Their operation is submitted to a critical appraisal.
    Additional Material: 18 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cite.330630303
    Location Call Number Limitation 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...