ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Organic Chemistry  (9,519)
  • Life and Medical Sciences  (9,191)
  • Animals  (5,805)
  • 1995-1999  (9,475)
  • 1980-1984  (9,026)
  • 1975-1979  (6,014)
Collection
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 165 (1980), S. 41-54 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Histology and cytology of dermal scales of the gymnophionans Ichthyophis kohtaoensis and Hypogeophis rostratus reveal their structure and the nature of their mineralization.Dermal scales are small flat disks set in pockets in the transverse ridges of the skin. Each pocket contains several scales of various sizes. A ring of “hypomineralization” of varying diameter may occur on scales of a particular dermal pocket but bears no relation to the diameter of these scales.Three different layers form the scales and are seen on sections perpendicular to the surface. The cells of the basal layer lie deepest. Each of the two or three more superficial fibrous layers is composed of bundles of fibres that are oriented in parallel. The orientation varies among layers. The striation of the fiber scales has a periodicity comparable to that of the surrounding dermal fibers. Squamulae form a discontinuous layer on the scale surface and are the only mineralized part of the scale. The minerals are deposited both on the collagen fibers passing from the fibrous layers into the squamulae, and in the interfibrillar spaces. Spherical concretions, either isolated or coalescent, reaching up to 1 μm, are found on the surface of the squamulae.The dermal scales of Gymnophiona present some analogies with those of evolved bony fishes. Their characteristics could make them an original model for the study of mineralization.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 324 (1982), S. 964-972 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Investigations on the Thermal Decomposition of n-Dodecylcyclopentane in the Gas PhaseIn the thermal decomposition of n-dodecylcyclopentane at 670 and 750°C in a laboratory tubular reactor mixtures of hydrogen and 57 and 113 hydrocarbons respectively are formed. The mixtures have been analyzed and identified by capillary gas chromatography and by mass spectrometry. The distribution of the reaction products is used for mechanistic discussions.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 325 (1983), S. 66-74 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Kinetic Investigations of the Pyrolysis of Mono-n-alkyl-cyclohexanesThe thermal decomposition of cyclohexane and six mono-n-alkylcyclohexanes was studied kinetically in a metallic laboratory tubular reactor at 650 to 850°C and atmospheric pressure.Kinetic parameters were found to be a function of length of the alkylic side chain. A comparison with analogous parameters of n-paraffins and the unsubstituted cyclohexane allowed the conclusion that C—C-scission in the alkylic chain is the initial reaction in pyrolysis of n-alkylcyclohexanes followed by radical attacks to all C—H-bonds of the feed molecules.
    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
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 321 (1979), S. 1000-1006 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Model Calculations on the Counterion Effect in the Cationic Polymerization; Decay of the Mixed Halogenoantimonates SbCl5Br- and SbClBr5-The decay of the halogenoantimonates SbCl5Br- and SbClBr5- according to SbCl5Br- → SbCl5 + Br- resp. SbCl4Br + Cl- and SbClBr5- → SbBr5 + Cl- resp. SbClBr4 + Br- has been investigated by the quantum-chemical CNDO/2 method including geometry optimization. The calculations show that the dissociation of the Sb—Cl bond needs more energy (7,8 kcal/mol) than the dissociation of the Sb—Br bond.Dissociation of the complex anions is facilitated with increasing Br content.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 162 (1995), S. 36-43 
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Insulin-like growth factor II (IGF II) regulated tissue-specific gene expression in hepatoma cell lines, but had no effect on expression of tissue-specific genes in primary cultures of E14 and newborn rat liver cells depleted of erythroid cells. No change was observed in these primary cultures with respect to α-fetoprotein (α-FP), albumin, cytokeratin 19 (CK 19), γ-glutamyltranspeptidase (GGT), and IGF II receptors. Two well-differentiated hepatomas, HepG2 and FTO-2B, and a poorly differentiated hepatoma, H4AzC2, did not show increased proliferation in the presence of IGF II, yet showed gene expression changes in response to IGF II. In HepG2 cells, IGF II increased albumin mRNA levels and resulted in a shift from clusters of cells positive to 100% of the cells expressing immunohistochemically detectable albumin. The transcription factor HNF-3β mRNA and protein levels of the bile duct markers, CK19 and GGT, were also increased in the presence of IGF II. Other genes tested were not affected, including α 1-antitrypsin, and two liver specific transcription factors, HNF-4 and HNF-3α. In FTO-2B cells, IGF II increased the expression of albumin, CK19, and GGT, without accompanying changes in albumin and GGT mRNAs. In H4AzC2 cells, IGF II reduced CK19 and OC.3 protein levels and GGT, transferrin, and HNF-3β mRNAs. The effects of IGF II on H4AzC2 cells were not blocked in the presence of an anti-rat IGF II receptor antibody. We conclude that IGF II affects tissue-specific gene expression of hepatomas and qualitative and quantitative aspects of its influence on the hepatomas is dependent on their degree of differentiation. © 1995 Wiley-Liss, Inc.
    Additional Material: 4 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
    Biologie in unserer Zeit 25 (1995), S. 29-36 
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Obwohl die Neurobiologie in den letzten Jahren einen enormen Aufschwung erfahren hat, ist noch immer sehr wenig über die zentralnervösen Grundlagen für die Steuerung von Verhaltensweisen bekannt. Voraussetzung für die Erforschung dieses Phänomens ist ein geeignetes Modellsystem: Das zu untersuchende Verhalten muß klar definiert und leicht zu messen sein; die wesentlichen Elemente des zentralnervösen Schaltkreises, der diese Verhaltensweise kontrolliert, sollten bekannt sein; und schließlich muß es möglich sein, die Häufigkeit, mit der diese Verhaltensweise auftritt, im Experiment zu verändern. Alle drei Forderungen sind in besonderer Weise bei schwachelektrischen Messerfischen erfüllt. Diese unscheinbaren Aquarienbewohner eröffnen damit die Möglichkeit, einen Einblick in die Komplexität der Steuerung von Verhalten durch das Gehirn zu erhalten.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; chromosome XV sequencing ; expressed sequence tags ; ADH1 ; COQ3 ; MSH2 and RCF4 ; transmembrane proteins ; organelle targeting ; ARS ; GCN4 ; Arabidopsis thaliana ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The nucleotide sequence of a 29·425 kb fragment localized on the left arm of chromosome XV from Saccharomyces cerevisiae has been determined. The sequence contains 13 open reading frames (ORFs) of which four encode the known genes ADH1, COQ3, MSH2 and RCF4. Predictions are made concerning the functions of the unknown ORFs. Some of the ORFs contain sequences similar to expressed sequences tags (EST) found in the database made available by TIGR. In particular, the highly expressed ADH1 gene is represented in this database by no less than 20 EST sequences. Two ARS sequences and a putative functional GCN4 motif have also been detected. One ORF (O0953) containing nine putative transmembrane segments is similar to a hypothetical membrane protein of Arabidopsis thaliana. Characteristic features of the other ORFs include ATP/GTP binding sites, a fungal Zn(2)-Cys(6) binuclear centre, an endoplasmic reticulum targeting sequence, a β-transducin repeat signature and in two instances, good similarity to the prokaryotic lipoprotein signal peptide motif. The sequence has been deposited in the EMBL data library under Accession Number X83121.
    Additional Material: 5 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
    Chirality 10 (1998), S. 362-363 
    ISSN: 0899-0042
    Keywords: Jacobsen's catalyst ; enantiomeric purity determination ; chiral HPLC ; cyclodextrin chiral stationary phases ; enantioseparation ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A HPLC method is described for the chiral analysis of the commercially available Jacobsen's catalyst. A hydroxypropyl β-cyclodextrin stationary phase was used in conjunction with a nonaqueous, polar-organic mobile phase. The method can be applied to control the enantiomeric purity of the catalyst, which is of great importance for quality control of that product. High accuracy in the determination of trace levels of the unwanted enantiomer in the presence of large amounts of the desired enantiomer is demonstrated. Chirality 10:362-363, 1998. © 1998 Wiley-Liss, Inc.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 28 (1998), S. 64-71 
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Viele Erkenntnisse über das Geschehen in einer Zelle vermitteln uns das Bild eines Fließgleichgewichts, das es der Zelle erlaubt, sich flexibel auf änderungen der Umwelt einzustellen. Während dieses Prinzip für Stoffwechselprozesse schon lange akzeptiertes Lehrbuchwissen darstellt, haben Untersuchungen zum Proteinabbau dieses Dogma nun auch auf proteolytische Prozesse erweitert. Die meisten zelluläen Proteine werden ständig neu gebildet und ebenso auch wieder abgebaut. Hierbei können sich ihre individuellen Halbwertszeiten je nach Funktion der Proteine stark voneinander unterscheiden. So besitzen Enzyme, die wichtige metabolische Kontrollfunktionen in der Zelle ausüben, Halbwertszeiten im Bereich von Minuten, während andere Proteine über Monate stabil vorliegen können. Der gezielte Proteinabbau stellt für die Zelle ein wirkungsvolles Kontrollinstrument dar, um die Konzentrationen wichtiger regulatorischer Proteine schnell und irreversibel zu senken. Auf diese Weise kann sich die Zelle zudem von abnormalen, wie zum Beispiel falsch gefalteten oder mutierten, und damit funktionsunfähigen Proteinen befreien, deren Ansammlung sie auf längere Sicht hin schäadigen würde. überdies werden wertvolle Aminosäurebausteine im Sinne eines effektiven Recyclings wieder zur Synthese neuer Proteine eingesetzt. Da die Proteinbiosynthese ein energieaufwendiger Prozeß ist, muß der regulierend eingesetzte Proteinabbau einer strikten Kontrolle unterliegen. Wir beginnen gerade zu verstehen, wie die Zelle das Kunststück fertigbringt, aus der großen Vielzahl aller zelluläen Proteine mit hoher Präzision diejenigen auszuwählen, die zu einem bestimmten Zeitpunkt abgebaut werden sollen.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The conjugate addition of the chiral, non-racemic alkoxy-enolates 5 and 6 to nitroolefins furnishes the hydroxynitroesters 7-13, which are catalytically hydrogenated to give the lactams 14-18. The configuration of adduct 7 from nitroethylene was elucidated by NMR. analysis of the acetal 20 derived from 7. The assignment establishes that the reaction follows the stereochemical rule of attack depicted in 21 and previously deduced for other electrophiles, i.e. formation of erythro-products of type 3b and 4b. No stereocontrol was found at the newly formed chiral centers in α- and β-position to the NO2 group of 8-12.
    Additional Material: 1 Tab.
    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...