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  • 1995-1999  (13)
  • 1965-1969  (3)
Materialart
Erscheinungszeitraum
Jahr
  • 1
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 66 (1995), S. 4902-4910 
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: A Penning trap system has been set up for storing and investigating cluster ions over time ranges from microseconds up to minutes. This enables studies of cluster reactions with extremely low cross sections and the observation of their time dependence in a new regime. The ions are created externally by laser vaporization, cooled by adiabatic expansion of a supersonic beam, and injected into the Penning trap. Detection of reaction products is achieved by combining the advantages of two complementary approaches, viz. the high resolution of Fourier transform mass spectrometry and the high sensitivity of single-ion counting with a time-of-flight mass spectrometer. The performance of the apparatus is illustrated by results of recent cluster experiments. © 1995 American Institute of Physics.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Journal of neurology 194 (1968), S. 296-310 
    ISSN: 1432-1459
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung In Ergänzung früherer Untersuchungen werden an Hand von Abbildungen klinischer und besonders tierexperimentell erzeugter Liquorzellpräparate die Ergebnisse zur formalen Genese der Riesenzellen besprochen und vier Bildungswege für die Entstehung der Riesenzellen im Bereich des Subarachnoidalraumes aufgezeigt. Dabei konnte festgestellt werden, daß der primär syncytialen Entstehung der Riesenzellen (Fresen) neben der amitotischen Kern- ohne Plasmateilung eine besondere Bedeutung bei der Bildung mehr- oder vielkerniger Riesenzellen zukommt. Darüber hinaus lassen sich in der mitotischen Kernteilung und Confluenz von Einzelzellen zwei weitere Bildungsmöglichkeiten nachweisen. Allerdings kommt diesen beiden Entstehungsformen nur eine untergeordnete Bedeutung zu, da sie nur relativ selten im Liquorzellsediment anzutreffen sind. Auch wenn diese Befunde besonders an Fremdkörperriesenzellen erhoben wurden, muß für die Langhansschen Riesenzellen die gleiche Genese angenommen werden. Die unterschiedlichen Ansichten bei der Entstehung der Riesenzellen werden danach aufgezeigt und im einzelnen diskutiert. Abschließend werden einige Fragen zur kausalen Genese der Riesenzellen erörtert. Da sich die Riesenzellen wie die reticulären Zellen und somit Makrophagen im Liquor aus dem leptomeningealen Mesenchym entwickeln, biologisch vollwertig und zur Phagocytose befähigt sind, kann man sie auch als eine besondere Form der reticulären Makrophagen bezeichnen.
    Notizen: Summary In expanding previous studies, micrographs of preparations of cerebrospinal fluid cells obtained from clinical cases and particularly from animal experiments were evaluated. The results are discussed as they relate to the morphogenesis of giant cells. Four possible ways in which giant cells may develop in the subarachnoid space are suggested. Besides the amitotic division of nuclei without division of the cytoplasm, the primary syncytial formation of giant cells (Fresen) was found to be of particular significance for the development of bi- or multinuclear cells. In addition, the mitotic mode of division of the nucleus and the fusion of single cells are two other ways. However, the latter two possibilities are of lesser importance as they are only seldomly seen in cell sediments of cerebrospinal fluid. The assumptions presented above are also to hold true of the formation of Langhans' giant cells even though the observations of the present study were made on foreign body giant cells. The different opinions expressed on the formal evolution of giant cells are pointed out and discussed in detail. Some aspects of the causes entailing the formation of giant cells are considered. Giant cells may also be termed a special form of reticular macrophages since the giant cells of cerebrospinal fluid arise from the leptomeningeal mesenchyma similarly to reticular cells, i.e. macrophages, and since they are biologically viable and capable of phagocytosis.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Journal of neurology 188 (1966), S. 300-307 
    ISSN: 1432-1459
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Es wurden nahezu zellfreie Liquores von 60 Patienten mit verschiedenen Erkrankungen des ZNS und 5 Kontrollpersonen auf den Gehalt an folgenden, meist zellstrukturgebundenen Oxydoreduktasen untersucht: NADH2- und NADPH2-Oxydasen mit O2 als Elektronenacceptor, endogene NADH2- (NADPH2)-Oxydationsraten, NADH2- und NADPH2-Oxydoreduktasen mit Ferricyanid und 2,6-Dichlorphenolindophenol als Elektronenacceptoren, Vitamin K3-Reduktase, NADH2- und NADPH2-Cytochrom c-Reduktasen und Glutathionreduktase. NADH2- und NADPH2-Oxydasen mit O2, Ferricyanid und 2,6-Dichlorphenolindophenol als Elektronenacceptoren, Vitamin K3-Reduktase und NADPH2-Cytochrom c-Reduktase waren in keinem Fall nachweisbar. Nur in zwei von 20 untersuchten Liquores von Patienten mit gefäßbedingten Blutungen konnte das Vorkommen von NADH2-Cytochrom c-Reduktase gesichert werden. Ein Liquor von getesteten Tumorpatienten enthielt deutlich Glutathionreduktaseaktivität. Ansonsten fanden sich beide letztgenannten Fermente in keinem weiteren Liquor. Die endogene NADH2-Oxydationsrate betrug bei Tumoren im pH-Optimum (6–6,5) 7, bei allen übrigen Fällen etwa 3 μ M/min und 1000 ml Liquor. Eine endogene NADPH2-Oxydation wurde in keinem Fall beobachtet. Die Frage nach dem Austritt strukturgebundener Oxydoreduktasen (Elektronentransportfermente) in den Liquor bei verschiedenen Erkrankungen des ZNS muß am Beispiel der getesteten Enzyme vorerst verneint werden.
    Notizen: Summary The following oxidoreductases were measured in nearly cell-free specimens of cerebrospinal fluid from 60 patients with various diseases of the CNS and from 5 normal controls: NADH2 (NADPH2)-oxidases with molecular oxygen, ferricyanide or 2,6-dichlorophenolindophenol as electron acceptors; the rates of endogenous NADH2 (NADPH2)-oxidation and activities of vitamine K3 reductase, NADH2 (NADPH2)-cytochrome c reductases and glutathione reductase. There were no oxidase activities at all when molecular oxygen, ferricyanide and dichlorophenolindophenol served as electron acceptors nor vitamine K3 reductase or NADPH2-cytochrome c reductase activities. Only 2 out of 20 specimens of cerebrospinal fluid from patients with cerebrovascular hemorrhages exhibited NADH2-cytochrome c reductase activity. One of the tumor patients clearly showed glutathione reductase activity. No activities of these two enzymes were found in the other specimens. The rate of endogenous NADH2-oxidation at the optimal pH of 6–6.5 amounted to 7 μM per minute and 1000 ml cerebrospinal fluid in tumor patients and to 3 μM in all other cases. An endogenous NADPH2-oxidation was never demonstrable. Most of the enzymes investigated in this study are bound to cellular structures. They do not appear to be released into the cerebrospinal fluid in the disease entities which were subject of this investigation.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Journal of molecular medicine 47 (1969), S. 1268-1269 
    ISSN: 1432-1440
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Summary In cerebrospinal fluids (CSF) of patients with acute inflammatory cerebral diseases, brain atrophies and tumours of the CNS we observed a higher activity of adenosine deaminase than in normal persons. Activities in CSF of patients with epilepsies, vascular, degenerative and chronical inflammatory cerebral diseases did not differ from normal values. The range of activities found in normal CSF was 0–0,26 IU. The results were discussed. The estimation of adenosine deaminase activity in CSF was commended as an additional diagnostical method in unclear neurological diseases.
    Notizen: Zusammenfassung Im Liquor läßt sich zu hohen Prozentsätzen bei akut entzündlichen cerebralen Erkrankungen, Hirnatrophien und Tumoren im Bereich des ZNS eine erhöhte spezifische Aktivität der Adenosindesaminase nachweisen. Die übrigen untersuchten Krankheitsbilder, wie Epilepsien, gefäßbedingte, degenerative und chronisch entzündliche Erkrankungen des ZNS zeigten keine Unterschiede zur Normalaktivität, die in einem Bereich von 0–0,26 IE festgelegt wurde. Die Befunde werden diskutiert und die Bestimmung der Adenosindesaminase in Liquores als ergänzende Untersuchung bei neurologisch unklaren Erkrankungen empfohlen.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    The European physical journal 352 (1995), S. 373-390 
    ISSN: 1434-601X
    Schlagwort(e): 21.10.Sf ; 21.60.Cs ; 23.20.-g ; 27.60.+j
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract The neutron deficient nuclei98Ag,104Sn withT z =2 and103In,105Sn (T z=5/2) were studied in-beam following the reaction of 250 MeV58Ni+50Cr. Neutron and charged particle (p, α) gatedγγ-coincidence spectra were used to identify these nuclei, which are populated with yields between 0.05% and 2% of the total residue cross section, and to determine their level schemes. In a comprehensive shell model study various approaches for the residual interaction were used to describe these newly and several previously studied neutron deficient nuclei. As a result predictions for the neutron single particle energies for100Sn are obtained and used to discuss the next generation of experiments.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 6
    ISSN: 1434-601X
    Schlagwort(e): 23.20.Lv ; 27.60.+j ; 21.60.Cs
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract An extended level scheme of109Sn is presented showing high-spin states up to Ex≈ 8 MeV and spins up toJπ=(41/2+). Their decay to the 5/2+ ground state has been observed identifying a 12.8 keV 7/2+ → 5/2+ transition. A half-life of T1/2=7(1) ns has been measured for the 17/2+ state atE x =2114 keV. The experimental data are compared with the predictions of shell-model calculations.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Rheumatology international 18 (1998), S. 35-36 
    ISSN: 1437-160X
    Schlagwort(e): Key words Fibromyalgia ; Serotonin ; Substance P ; Pain ; Acupuncture ; Therapy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The lack of objective parameters makes the measurement of pain and the efficacy of pain treatment in patients with chronic pain very difficult. We performed acupuncture therapy in fibromyalgia patients and established a combination of methods to objectify pain measurement before and after therapy. The parameters corresponded to patients' self-report. Twenty-nine fibromyalgia patients as defined by ACR-criteria (25 women, 4 men) with a mean age of 48.2±2.0 years and a mean disease duration of 6.1±1.0 years participated in the study. Pain levels and positive tender points were assessed using the visual analogue scale (VAS, i.e., range 0–100 mm) and dolorimetry. Serotonin and substance P levels in serum and the serotonin concentration in platelets were measured concomitantly. During acupuncture therapy no analgesic medication was allowed. The VAS scores decreased from 64.0±3.4 mm before therapy to 34.5±4.3 mm after therapy (P〈0.001). Dolorimetry revealed a decreased number of tender points after therapy from 16.0±0.6 to 11.8±1.0, P〈0.01. Serotonin levels decreased from 715.8±225.8 μg/1012 platelets to 352.4±47.9 μg/1012 platelets (P〈0.01), whereas the serum concentration increased from 134.0±14.3 ng/ml to 171.2±14.6 ng/ml (P〈0.01). Substance P levels in serum increased from 43.4±3.5 pg/ml to 66.9 ±8.8 pg/ml (P〈0.01). Acupuncture treatment of patients with fibromyalgia was associated with decreased pain levels and fewer positive tender points as measured by VAS and dolorimetry. This was accompanied by decreased serotonin concentration in platelets and an increase of serotonin and substance P levels in serum. These results suggest that acupuncture therapy is associated with changes in the concentrations of pain-modulating substances in serum. The preliminary results are objective parameters for acupuncture efficacy in patients with fibromyalgia.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 8
    ISSN: 1572-9540
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract First direct mass measurements on rare earth isotopes around 146Gd have been performed with the Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN. More than 40 isotopes of the elements Pr, Nd, Pm, Sm, Eu, Dy and Ho have been measured with an accuracy of typically 1 × 10-7. In the case of 141Sm isomeric and ground state (ΔE = 175 keV) were resolved. Since isobaric contaminations are present in the ISOLDE beam, these measurements on rare earth isotopes became only possible after the installation of a new cooler trap which acts an isobar separator.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 9
    Digitale Medien
    Digitale Medien
    Springer
    Hyperfine interactions 108 (1997), S. 0-0 
    ISSN: 1572-9540
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 10
    Digitale Medien
    Digitale Medien
    Springer
    Hyperfine interactions 108 (1997), S. 207-218 
    ISSN: 1572-9540
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract High-accuracy mass measurements have recently been performed on radioactive isotopes produced by proton-induced spallation at the on-line isotope separator ISOLDE at CERN and by heavy-ion projectile fragmentation at the fragment separator FRS at GSI. At ISOLDE, singly charged ions were injected into the Penning trap mass spectrometer ISOLTRAP and their masses determined by observing their cyclotron frequencies in the homogeneous magnetic field of the ion trap. At GSI, bare, hydrogen, or helium-like ions were injected into the experimental storage ring ESR, electron-cooled to the same velocity, and their masses determined by observing their revolution frequencies in the ESR. With ISOLTRAP and ESR, resolving power in the range of 4 × 105〈 = m/Δ m(FWHM)〈 = 107 and an accuracy up to \delta m/m~ 10-7 were achieved for radioactive isotopes. Mass measurements of highly charged ions of stable isotopes were performed at Stockholm by use of SMILETRAP. In this case, a resolving power of about 108 and an accuracy close to 10-9 were obtained.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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