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  • 1
    ISSN: 1433-0423
    Keywords: Schlüsselwörter Autofluoreszenz ; Lipofuszin ; Retinales Pigmentepithel ; Altersabhängige Makuladegeneration ; Makuladystrophie ; Key words Autofluorescence ; Lipofuscin ; Retinal pigment epithelium ; Age-related macular degeneration ; Macular dystrophy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Background: We investigated fundus autofluorescence in vivo using a novel scanning laser ophthalmoscope. Materials and methods: A total of 550 patients with various retinal diseases were examined and compared with normal eyes. Autofluorescence was detected after excitation with an argon blue laser (488 nm), and emission was recorded with a short wavelength cut off above 500 nm. Results: Reduced autofluorescence was observed in the foveal and parafoveal region due to retinal xanthophyll, along the retinal vessels, at the optic nerve head and in areas with atrophy of the retinal pigment epithelium (RPE). Autofluorescence intensity was increased either focally or diffusely in certain degenerative (AMD) or genetically determined retinal diseases (e. g., Stargardt's disease, Best's disease). Conclusions: These findings are in accordance with the view that in vivo fundus autofluorescence originates at the level of the RPE and suggest that it is derived from lipofuscin.
    Notes: Hintergrund: Wir untersuchten die Erfassungsmöglichkeiten der Fundusautofluoreszenz und deren topographische Verteilung mit einem neuen konfokalen Scanning-Laser-Ophthalmoskop. Material und Methode: 550 Augen normaler Probanden und Patienten mit verschiedenen retinalen Erkrankungen wurden mit dem Heidelberg-Retina-Angiograph (HRA) untersucht. Die Fundusautofluoreszenz wurde nach Exzitation mit einem Argonlaser (488 nm) und Detektion des emittierten Lichts oberhalb von 500 nm erfaßt. Ergebnisse: Im Bereich makulären Xanthophylls, retinaler Gefäße, der Papille und Atrophie des retinalen Pigmentepithels (RPE) war die Autofluoreszenz vermindert. Genetisch determinierte und degenerative retinale Veränderungen gingen z. T. mit erhöhter, irregulärer Autofluoreszenzintensität einher (u. a. Morbus Best, Morbus Stargardt, AMD). Schlußfolgerung: Der Heidelberg-Retina-Angiograph ermöglicht die topographische Erfassung der Fundusautofluoreszenz in vivo. Die Befunde unterstützen die Annahme, daß die Autofluoreszenz durch Akkumulation von Lipofuszingranula im RPE induziert wird.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1434-193X
    Keywords: Lanthanides ; Polydentate ligands ; Luminescence spectroscopy ; Near-infrared luminescence ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: ---A series of m-terphenyl-based ligands bearing three coordinating oxyacetate and two amido or two sulfonamido groups, (1a-b)H3 and (2)H3, respectively, have been synthesized and characterized. The structures of the corresponding neutral complexes have been studied using 1H-NMR spectroscopy and luminescence experiments. The photophysical properties of the (1a-b)Eu, (2)Eu, (1a)Tb, and (2)Tb complexes have been studied to determine the structure of the first coordination sphere in methanol. The first coordination sphere consists of eight donor atoms provided by the ligand (three chelating oxyacetate groups and two amide or sulfonamide oxygens), and one methanol molecule. The (1a)Dy and (1a)Sm complexes exhibited sensitized luminescence in the visible spectral region, but the luminescence intensity was very sensitive to quenching by C-H groups. The near-infrared emitting (1a)Ln and (2)Ln complexes exhibited sensitized luminescence at wavelengths (at 880, 1060, and 1330 nm for Nd3+, at 980 nm for Yb3+, and at 1550 nm for Er3+) of interest for applications in optical telecommunication devices. The luminescence lifetimes of these complexes in DMSO and [D6]DMSO are in the range of microseconds. The luminescent state of the NIR emitting lanthanide ions is very efficiently quenched by high frequency oscillators (such as C-H groups) in the solvent and the ligand.Supporting information for this article is available on the WWW under //http://www.wiley-vch.de/contents/jc_2046/2000/99457_s.pdf or from the author.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1433-0423
    Keywords: Key words Scanning laser ophthalmoscopy ; Fluorescein angiography ; Indocyanine green angiography ; Choroidal neovascularization ; Age-related macular degeneration ; Schlüsselwörter Scanning-Laser-Ophthalmoskopie ; Fluoresceinangiographie ; Indozyaningrünangiographie ; Choroidale Neovaskularisation ; Altersabhängige Makuladegeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Fragestellung: Wir berichten über klinische Erfahrungen mit einem neuen konfokalen Scanning-Laser-Ophthalmoskop zur simultanen Fluorescein- und Indozyaningrün (ICG)-Angiographie. Material und Methode: Die digitalen Aufnahmen erfolgten nach gleichzeitiger Injektion von Fluorescein und ICG mit dem Heidelberg-Retina-Angiograph (HRA). Als Erregerlicht wurden ein Argon- (488 nm) und ein Diodenlaser (795 nm) angewendet. Die Emission wurde zwischen 500 und 650 nm bzw. über 810 nm erfaßt. Ergebnisse: Insgesamt wurden 295 simultane Angiogramme bei verschiedenen Fundusveränderungen einschließlich exsudativer altersabhängiger Makuladegeneration durchgeführt. Die Aufnahmen zeichneten sich durch einen hohen Kontrastreichtum aus. Die Mischung und gleichzeitige Injektion beider Farbstoffe war nicht mit zusätzlichen Nebenwirkungen assoziiert. Schlußfolgerung: Mittels des HRA ist eine simultane Fluorescein- und ICG-Angiographie möglich. Im Vergleich zu konsekutiven Angiographien mit beiden Farbstoffen besitzt sie den Vorteil des geringeren Zeitaufwands, einer nur 1maligen Farbstoffinjektion sowie eine einfachere Interpretation aufgrund der simultanen Darstellung der jeweils farbstofftypischen Befunde.
    Notes: Background: We report on our clinical experience with a recently developed confocal scanning laser ophthalmoscope for simultaneous fluorescein and indocyanine-green (ICG) angiography. Materials and methods: Following injection of fluorescein and ICG mixed in one syringe simultaneous confocal scanning laser fluorescein and ICG angiography were carried out using the Heidelberg Retina Angiograph (HRA). An argon laser (488 nm) and a diode laser beam (795 nm) from an external source were delivered via single-mode fibers. Emission was recorded between 500 and 650 nm and above 810 nm, respectively. Digital images were displayed simultaneously on a monitor during angiography. Results: A total of 295 simultaneous angiograms in 268 patients with various retinal and choroidal diseases, including exudative age-related macular degeneration with occult and classic choroidal neovascularization, were obtained. High-contrast images during all phases of the angiography were obtained. Besides mild side effects in similar frequency known from individual injections, no additional toxic or allergic reactions from simultaneous injections of the two dyes were observed. Conclusions: Confocal laser scanning angiography allows for simultaneous fluorescein and ICG angiography. Compared with consecutive investigations using both dyes, simultaneous angiography requires only one injection, and offers identical digital frames. Simultaneous injection is not associated with additional side effects.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1433-0423
    Keywords: Schlüsselwörter Indozyaningrünangiographie ; Heidelberg-Retina-Angiograph ; Choroidale Neovaskularisation ; Altersabhängige Makuladegeneration ; Key words Indocyanine green angiography ; Heidelberg Retina Angiograph ; Choroidal neovascularization ; Age-related macular degeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: ``Classic'' choroidal neovascularization (CNV) has a relatively uniform appearance in fluorescein angiography. In contrast, indocyanine green (ICG) angiography shows variable features of well-defined CNV. We examined 31 classic CNV patients secondary to age-related macular degeneration using a confocal laser scanning ophthalmoscope (Heidelberg Retina Angiograph) in order to determine ICG characteristics of classic CNV. Vascular patterns (97%), a hypofluorescent rim (84%), a hyperfluorescent margin (42%), late ICG leakage (32%) and ``feeder vessels'' were identified in variable frequency. Some of the ICG characteristics may correlate with histological features of the membrane and reflect proliferative activity. Extrafoveal ``feeder vessels'' may be amenable to laser photocoagulation in the presence of subfoveal CNV.
    Notes: Klassische choroidale Neovaskularisationen (CNV) stellen sich in der Fluoresceinangiographie relativ uniform dar, während sie in der Indozyaningrün (ICG)-Angiographie unterschiedliche Aspekte zeigen. Zur weiteren Bestimmung ICG-angiographischer Charakteristika wurden 31 Patienten mit klassischer CNV bei altersabhängiger Makuladegeneration mittels eines konfokalen Scanning-Laser-Ophthalmoskops (Heidelberg-Retina-Angiograph) untersucht. In unterschiedlicher Häufigkeit wurden abgrenzbare Gefäßmuster (97%), ein hypofluoreszenter Randsaum (84%), ein hyperfluoreszenter Membranrand (42%), ICG-Leckagen (32%) und umschriebene Feeder vessels (29%) erkannt. Die ICG-angiographischen Besonderheiten einzelner CNV gehen auf histologische Merkmale der Membran zurück und lassen ggf. Rückschlüsse auf das Ausmaß der proliferativen Aktivität zu. Extrafoveal darstellbare sog. Feeder vessels könnten insbesondere bei subfovealer CNV einer Laserkoagulation zugänglich sein.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 46 (1933), S. 583-584 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Konformationsumwandlungen in N-Methyl-azacyclohexanen haben eine Besonderheit: Sie können sowohl unter Ringinversion als auch unter Stickstoffinversion verlaufen. Durch beide Vorgänge wird eine äquatoriale N-Methylgruppe in eine axiale umgewandelt und umgekehrt. Es ist zweckmäßig, die Energiebarrieren für die N-Methylinversion in zwei “Halbbarrieren„ für die Schritte axiale Form → Übergangszustand und äquatoriale Form → Übergangszustand zu zerlegen und beide Werte getrennt anzugeben. - In diesem Beitrag werden die N-Methylinversionsbarrieren zahlreicher methylierter Oligoazacyclohexane, auch mit Sauerstoff- oder Schwefelatomen im Ring, diskutiert.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 0570-0833
    Keywords: Inversion barriers ; Inversion barriers ; Conformation analysis ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Conformational conversions of N-methylazacyclohexanes are of particular interest: they can proceed either via ring- or nitrogen-inversion processes. In both procedures an equatorial N-methyl group is converted into an axial one, and the converse. It is appropriate to dissociate the energy barriers for N-methyl inversion into two “half-barriers” for the steps, axial form → transition state and equatorial form → transition state, and to report both values separately. - In this article the N-methyl inversion barriers of numerous methylated oligoazacyclohexanes, including species with oxygen or nitrogen atoms in the ring, are discussed.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 44 (1931), S. 342-348 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 47 (1934), S. 832-832 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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