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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    World journal of surgery 8 (1984), S. 399-399 
    ISSN: 1432-2323
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Breast cancer research and treatment 4 (1984), S. 79-88 
    ISSN: 1573-7217
    Keywords: breast ; carcinoma ; DNA ; kinetics ; ploidy ; receptors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The S-phase fraction (SPF) measured by flow cytometry of DNA and the thymidine labeling index (TLI) measured autoradiographically indicate the proportion of carcinoma cells currently synthesizing DNA and reflect the rate of proliferation. The TLI and SPF are lognormally distributed. The median TLI performed to maximize precursor uptake is near 5% (5 labeled carcinoma cells per 100), the mean near 7%, and the range from less than 1% to near 40%. Corresponding values for the SPF measured by DNA flow cytometry are slightly higher when appropriate measures are taken to reduce background debris counts and other artefacts. Residual elevation of SPF above TLI may result from S-phase arrested cells. Flow cytometric histograms show that clearly aneuploid cell lines exist in 50–80% of primary breast carcinomas. Aneuploid breast carcinomas have higher mean TLI than diploid breast carcinomas, and therefore proliferate more rapidly. They also more frequently lack estrogen receptor (ER). Carcinomas with minimal nuclear anaplasia, particularly those of tubular, mucinous, infiltrating lobular and adenocystic types have low TLI and SPF, whereas carcinomas with highly anaplastic nuclei, including medullary carcinomas, have high TLI and SPF. TLI and SPF correlate inversely with ER and PgR content, have no relationship to axillary lymph nodal status, and have a weak positive correlation with tumor size and a weak negative correlation with age. High TLI predicts a high risk of early relapse after primary therapy for both node-negative and node-positive carcinomas. Carcinomas that produce brain metastases have particularly high TLI. Current evidence suggests that high SPF and aneuploidy may prove to have prognostic significance like TLI.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 116 (1983), S. 1154-1173 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Fulvenes with Inverse Ring Polarization, 10. Electron Rich HeptafulvenesThe synthesis and structural properties of the electron rich heptafulvenes 3a - f are described. The compounds 3 have electron donor substituents at C-8. In the case of 3f NMR-spectroscopy revealed the presence of a boat conformation with bond alternation. HMO-calculations showed that, depending on the electron donor properties, the C-8 substituents lead to a characteristic “HOMO-LUMO-GAP-NARROWING”.  -  The new compounds 3a - f have been synthesized either from derivatives of 1,3,5-cycloheptatriene-7-carboxaldehyde or from cycloheptatriene-7-carboxylic acid.
    Notes: Synthesen und Struktureigenschaften der elektronenreichen Heptafulvene 3a - f werden beschrieben. Die Verbindungen 3 haben Donorsubstituenten an C-8. Am Beispiel des Bis(dimethylamino)heptafulvens 3f wurde mit 1H-NMR gezeigt, daß die Bootkonformation vorliegt und die C — C-Bindungen Bindungsalternanz zeigen. Zur weiteren Charakterisierung des π-Systems wurde das HMO-Modell verwendet: Charakteristisch ist insbesondere die Verringerung der Energielücke zwischen den Grenzorbitalen durch die Donorsubstituenten an C-8  -  Die Verbindungen 3a - f wurden entweder aus Derivaten des 1,3,5-Cycloheptatrien-7-carboxaldehyds oder der Cycloheptatrien-7-carbonsäure synthetisiert.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 67 (1984), S. 1972-1988 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Degree of Aggregation of Organolithium Compounds by Means of Cryoscopy in TetrahydrofuranThe association behaviour of alkyl-, aryl- and alkinyl-lithium compounds as well as of lithium enolates and chiral lithium azaenolates is determined from freezing-point depression values in dilute tetrahydrofuran solutions at -108°C. Compared toX-ray-crystallographic data (lithiated methyldithiane, phenyllithium, lithio derivatives of a ketone, carboxylic amide and -ester, and a diketopiperazine-bislactim-ether), desaggregation is found under these conditions. The structures determined by 13C-NMR spectroscopy for BuLi, lithiophenylacetylene and (t-butyl)lithioacetylene are confirmed. The dilithio salt of a carboxylic acid is polymeric, a chiral lithio-hydrazone and a chiral lithio-oxazolidine are monomeric and dimeric, respectively. Lithium diisopropylamide is a monomer-dimer equilibrium mixture. The apparatus described permits both synthesis and measurement of the reactive species under inert atmosphere conditions in the same vessel.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 115 (1982), S. 99-118 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloheptatrienes and Norcaradienes1): Relation between Hindrance of Rotation about the C-7-C-8 Bond and StructureIn order to elucidate factors responsible for substituent effects on cycloheptatriene-norcaradiene equilibria, the imidazolidinylium compound 12a and b, and the spiro molecules 13a and b are investigated. The synthesis of 12a starts from 7-cyanocycloheptatriene (14). Bisalkylation of dilithium heptafulvenediolate 17 affords 13. Compounds 12 and 13 are characterized by cycloadditions (→ 15, 22). Concerning the equilibrium 12a ⇌ 12b no norcaradiene could be traced by NMR. At room temperature 13a and b form a fast and dynamic equilibrium with [13a]:[13b] = 42:58. Thermodynamic parameters are given. The crystal structures of the compounds were determined by X-ray analysis. Both compounds are cycloheptatrienes with boat stereochemistry. The carbonyl group in 13a is exo, the cation substiuent in 12a is endo.
    Notes: Cycloheptatrien-7-ylimidazolidin-2-ylium-tetrafluoroborat (12a) wurde aus 7-Cyancycloheptatrien (14) und Aziridinium-tetrafluoroborat synthetisiert. Spirocycloheptatrien 13a und Norcaradien 13b entstehen durch cyclisierende Alkylierung des Dilithium-heptafulvendiolats 17. Mit Dienophilen bilden 12 und 13 die Polycyclen 15 und 22. NMR-Untersuchungen schließen einen nennenswerten Anteil von Norcaradien 12b im Gleichgewicht mit 12a aus. Dagegen stehen bei 284 K Cycloheptatrien 13a und Norcaradien 13b mit 42:58 im Gleichgewicht [ΔΔH0(NCD—CHT) = -1 kcal/mol, ΔΔS0(NCD—CHT) = -3 cal/Grad. mol]. Nach der Röntgenstrukturanalyse liegt 12a im Kristall in der Bootform mit endo-ständigem 7-Substituenten vor; von 13a ⇌ 13b ist im Kristall nur die Cycloheptatrienstruktur 13a mit exo-ständiger Carbonylgruppe stabil.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 116 (1983), S. 1777-1786 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cross Conjugated Enolates: Structure Characterization of Two Lithium HeptafulvenolatesWhen deprotonated, N,N-dimethylcycloheptatriene-7-carboxamide (2a) and cycloheptatriene-7-carboxylic acid (2c) yield the amide anion 4a and the acid dianion 4c. Due to the NMR spectra, 4a and c show in the range 600-700 nm three and two signals, respectively. The spectra are temperature and solvent dependent. The THF-solution of 4c is paramagnetic. The structures of the organolithium compounds are discussed.
    Notes: Die bei der Deprotonierung von N,N-Dimethylcycloheptatrien-7-carboxamid (2a) und Cycloheptatrien-7-carbonsäure (2c) entstehende Lithiumverbindung 4a und Dilithiumverbindung 4c werden spektroskopisch charakterisiert. 4a und c sind Heptafulvene, d. h. das Lithium ist am Sauerstoff lokalisiert. Die Elektronenspektren von 4a und c im Bereich 600-700 nm zeigen drei bzw. zwei Banden, deren Intensitäten von der Lösungsmittelzusammensetzung und der Temperatur abhängen. Die Lösung von 4c in Tetrahydrofuran ist paramagnetisch. Die Strukturen der lihiumorganischen Verbindungen werden diskutiert.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 117 (1984), S. 809-826 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Highly Unsaturated Radical Cations: Regio- und Stereochemistry of the Oxidative Dimerizations of HeptafulvenesThe oxidative dimerizations of heptafulvenes 3 yield bicycloheptatrienyl compounds 4, 5, 7, and 8 in single electron transfer reactions (SET). The C - C bond formation proceeds exclusively at the less hindered ring carbons. In all cases mixtures of regio- and stereoisomers are formed. Steric and electronic effects of the substituents influence the product distribution. The diester meso(u)-4a is thermically labile and rearranges to a complex mixture of bicycloheptatrienyls. The bicycloheptatrienyls are further characterized by cycloaddition reactions with 4-methyl-4H-1,2,4-triazole-3,5-dione (12a), leading to homobarrelenes. - The crystal structure of meso(u)-4a is determined by an X-ray analysis.
    Notes: Die oxidative Dimerisierung der Heptafulvene 3 führt zu Bicycloheptatrienyl-Verbindungen 4, 5, 7 und 8 über radikalische Zwischenstufen. Die C - C-Verknüpfung erfolgt an den sterisch weniger gehinderten Kohlenstoffen. Die Substituenten beeinflussen die Regio- und Stereoselektivität. Die thermische Labilität der Bicycloheptatrienyl-Verbindungen wird am Beispiel des Diesters meso (u)-4a gezeigt. Die Umlagerungsreaktion führt zu einer Vielzahl von Isomeren. Chemisch werden die Bicycloheptatrienyl-Verbindungen durch Addition von 4-Methyl-4H-1,2,4-triazol-2,5-dion (12a) charakterisiert, die zu Homobarrelenen führt. - Die Kristallstruktur von meso(u)-4a wird durch eine Röntgenstrukturanalyse bestimmt.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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