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
Filter
  • Wiley-Blackwell  (15)
  • 1990-1994  (15)
Collection
Year
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 143 (1990), S. 357-363 
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The uptake of chlortetracycline (CTC) and the nature of the fluorescence of CTC was studied in intact human erythrocytes from apparently healthy donors. The uptake of CTC at 22°C proceeded with a t½ of about 3 min, and after 15 min a stable equilibrium was achieved with an intracellular accumulation by a factor of 5-6 relative to the medium concentration. The accumulation did not change in the range of CTC concentrations tested (20-500 μM). The Ca specificity of the CTC fluorescence spectrum was confirmed by Ca depletion of red cells using A23187 in the presence of EGTA and 0.2 mM Mg. This procedure decreased the total intracellular calcium content by about 70% and reduced the fluorescence intensity to one-fourth. Fluorescence microscopy of red cells incubated with 100 μM CTC at 22°C showed that the fluorescence originated mainly from the red cell membrane. In addition, in about 15% of erythrocytes one or more fluorescent dots (diameter 〉0.2 〈1μm) were detected. The fluorescence of the dots and membranes was related to calcium, as evidenced by the reduction of their intensity in Ca depleted cells. The number of erythrocytes with fluorescent dots and the frequency of the dots per cell was largely unaffected by lowering the incubation temperature to 0°C, indicating that the dots most probably do not represent endocytotic artifacts induced by CTC. The number of dots was increased in erythrocytes preincubated with primaquine, demonstrating that CTC fluorescence can be applied to monitor the appearance of intracellular Ca storing vesicles. It is concluded that in (at least) 15% of erythrocytes obtained from apparently healthy donors intracellular vesicles containing Ca can be detected by CTC fluorescence microscopy.
    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: Aza sugars ; Glycosidase inhibitors ; Piperidine ring contraction ; Pyrrolidines ; Enzymes ; Carbohydrates ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Fragmentation of methyl 3-O-benzyl-6-bromo-2-O-(tert-butyldimethylsilyl)-6-deoxy-4-O-(4-methoxybenzyl)-α-D-mannopyranoside (2) and in situ reductive amination give (3R,4S,5R)-6-benzylamino-4-benzyloxy-5-(tert-butyldimethylsilyloxy)-3-(4-methoxybenzyloxy)hexene (3) which is converted by intramolecular aminomercuration into an epimeric mixture of the bromomercuriopiperidine derivatives 4 and 5. The minor D-manno epimer 4 is transformed into mesylate 10 which, upon reaction with LiN3 in DMF, suffers a piperidine-pyrrolidine ring contraction to give azidomethylpyrrolidine 11. Reductive acetylation by means of thioacetic acid affords the fully protected pyrrolidine aza sugar derivative 12. The major L-gulo epimer 5 is transformed into the mesylate 15 which, again, upon reaction with LiN3 in DMF undergoes piperidine-pyrrolidine ring contraction to give the 1-azido-3-O-benzyl-2,5-benzylimino-6-bromomercurio-1,2,5,6-tetradeoxy-4-O-(4-methoxybenzyl)-L-iditol (16). Eliminative dehalomercuration by means of Zn powder is accompanied by in situ reduction of the azido group to give amino alkene 17. Intramolecular aminomercuration of 17 followed by N-acetylation yields the protected 1,2,5,6-tetradeoxy-2,5-imino-D-glucitol derivative 20 as the major epimer. Reductive oxygenation of 20 leads to pyrrolidine 22 which is deprotected to give title compound 1. Selective cleavage of the PMB group of 22 leads to 24. Benzylation of 22 affords again 12 from which the OH group at C-4 is liberated by selective cleavage of the PMB ether to give pyrrolidine 13. Compound 1 inhibits NAGase from bovine kidney.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Cell Biochemistry and Function 11 (1993), S. 225-230 
    ISSN: 0263-6484
    Keywords: Electrophoresis ; endothelia ; glycoproteins ; lectins ; smooth muscle cells ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Endothelial and smooth muscle cells were isolated from porcine aorta and kept in short-term culture. To determine the terminal carbohydate composition of the plasma membranes from both cell populations, the cells were incubated with a panel of fluorescein-labelled lectins. Both cell populations shared a number of terminal carbohydrates, but the N-galactosamine specific lectin Wistaria floribunda agglutinin labelled only the endothelial cells. A lectin which selectively labelled smooth muscle cells was not found. Western blot analysis of isolated endothelial cell membrane glycoproteins indicated that most membrane glycoproteins are labelled by Wistaria floribunda agglutinin.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 65 (1993), S. 1121-1121 
    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
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 0009-286X
    Keywords: HTW-Vergasung ; Kohle ; Wirbelschicht ; Wirbelschichtvergasung ; Fluiddynamik ; Meßmethoden ; Synthesegas ; Kombikraftwerk ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Chemie Ingenieur Technik - CIT 64 (1992), S. 1109-1112 
    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
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 102 (1990), S. 347-361 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Als im Altertum König Hieron von Syrakus Archimedes vor die Frage stellte, ob ein für ihn handgearbeitetes Stirnband aus purem Gold gefertigt wurde, befestigte dieser das Stirnband und einen Klumpen aus purem Gold gleicher Masse an den Enden einer Balkenwaage und tauchte beide Gegenstände ins Wasser. Bekanntlich hob sich die Seite des Wägebalkens aus der Flüssigkeit, an der das Stirnband befestigt war. Dies war der Beweis dafür, daß der Goldschmied dem Schmuckstück Silber zugemischt hatte (Prinzip des Archimedes). Das klare und eindeutige Ergebnis des einfachen Experiments verdeutlicht die physikalische Integrität dieses klassischen Meßprinzips, das auf einer Gewichtsänderung beruht. Der Wägetechnik, über die in diesem Artikel berichtet wird, liegt zugrunde, daß die Änderung der Resonanzfrequenz eines Schwingquarzes quantitativ mit einer Massenänderung im Nanogrammbereich korreliert werden kann. Dies gilt auch für Quarzresonatoren, deren eine Seite mit einer Flüssigkeit in Kontakt steht. Nehmen wir an, daß die bei der Überprüfung von Hierons Schmuckstück beobachtete Gewichtsänderung etwa einige hundert Gramm betrug, so entspricht diese Gewichtsdifferenz einer Anzahl von etwa 1025 Wassermolekülen. Verwendet man die Quarzmikrowaage zur Untersuchung des Lösungsmitteltransports innerhalb dünner Schichten, so können Wassereinlagerungen bis zu 1014 Molekülen verfolgt werden. Bei der Untersuchung von Adsorbatschichten können Veränderungen bis zu 0.02 Monolagen detektiert werden. Beide Resultate belegen überzeugend, daß mit dieser in-situ-Technik Oberflächenprozesse am Übergang fest/flüssig mit mikroskopischer Auflösung verfolgt werden können. Die in-situ-Schwingquarzmethode läßt sich auf viele Fragestellungen aus unterschiedlichen Bereichen der Forschung und Entwicklung erfolgreich anwenden.
    Additional Material: 22 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 35 (1993), S. 127-133 
    ISSN: 1040-452X
    Keywords: DNA aneuploidy ; DNA cytophotometry ; Mosaicism ; FSH stimulation ; Preimplantation embryos ; Rabbit ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The DNA ploidy of Feulgen-stained cell nuclei of in vivo preimplantation rabbit embryos was assayed by cytophotometry. DNA ploidy abnormalities were detected in single-cell nuclei readings by the criterion of ≥5C DNA. These hypermodal DNA contents are referred as to DNA aneuploidy. Two, 4 and 6 days old rabbit embryos, all of normal gross morphology, were investigated.The incidence of embryos with DNA ploidy abnormalities increased from 17% in 2-day-old cleavage stages to 51% in 6-day-old expanded blastocysts. All these embryos were mosaics and the percentage of DNA aneuploid nuclei per embryo did not usually exceed 9%. Fifteen percent of the expanded blastocysts, however, contained up to 23% abnormal nuclei. Throughout the embryonic stages studied, the DNA content of abnormal nuclei was remarkably constant and averaged 5.8C. DNA aneuploid and euploid blastocysts did not differ in size. A maternal FSH treatment did not influence the DNA ploidy.This is the first report on the DNA ploidy pattern in preimplantation rabbit embryos. Our results indicate that DNA aneuploidy of single blastomeres is common in this species and occurs more often than generally assumed. The embryonic viability does not seem to be affected by the presence of DNA aneuploid blastomeres supporting earlier findings that a limited number of abnormal blastomeres is compatible with normal preimplantation development. © 1993 Wiley-Liss, Inc.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 152 (1992), S. 397-402 
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Cyclosporine A (CyA) is a powerful nonsteroidal immunosuppressive agent used to prevent graft rejection of organ and bone marrow transplants. A major side effect observed can be attributed to the fibroblast and its functions: proliferation of fibroblasts and formation of fibrotic tissue in the gingiva (fibrous hyperplasia) and in the kidney are induced. The mechanism of both is still obscure. In order to elucidate whether these side effects are due to the drug acting on human fibroblasts itself or whether they are indirect ones mediated by factors released by lymphocytes, cultures of human gingiva fibroblasts were exposed to CyA under defined in vitro conditions. Incubation with CyA for 72 hours resulted in a dosedependent stimulation of DNA synthesis, whereas glycosaminoglycan (GAG) synthesis was slightly suppressed. Long-term incubation (6 weeks) with 1 μg/ml CyA resulted again in stimulation of growth parameters: compared to the drug-free control, cell number increased to 168%, incorporation of 3H-thymidine into DNA to 143%, and overall protein content to 159%. Collagen and GAG synthesis were elevated to ∼ 120%. When corrected for cell number or cell protein content, this represents a decline in matrix synthesis, comparable to short-term incubations. These results indicate that a direct effect of CyA on proliferation of human gingival fibroblasts is responsible for some of the observed hyperplasia. © 1992 Wiley-Liss, Inc.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    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...