Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • sol-gel  (4)
  • D600  (3)
  • Electron microscopy  (3)
  • 1
    Digitale Medien
    Digitale Medien
    Springer
    Journal of molecular medicine 63 (1985), S. 176-183 
    ISSN: 1432-1440
    Schlagwort(e): Whipple's disease ; Electron microscopy ; Disturbed cellular immunology
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Whipple's disease is a curious disorder with the involvement of many organ systems, primarily gut, synovium and the central nervous system, characterized by the presence of numerous proliferating bacteria in tissue macrophages and other cell types. While clinically this disease entity has previously been defined by the classical triad of diarrhoea, malabsorption and weight loss, some patients do not show these features. In this report, a clinically unusual case of Whipple's disease is described presenting with high persistent fever, severe arthralgias and headaches, but without malabsorption, diarrhoea or weight loss. Nevertheless, the histological and electron microscopical pictures demonstrated the typical findings of intracellular micro-organisms along with the presence of bacteria in Schwann nerve cells, which has only once been described previously. Immunological findings before treatment demonstrated a decrease of T cells with the helper/inducer phenotype, and a concomitant rise in cells with the suppressor/cytotoxic phenotype, an elevation of “activated” Ia positive T cells and a significant reduction of T cell mitogenic responsiveness. Of special interest, after a successful treatment these immunological abnormalities shifted to normal with the exception of a still elevated number of Ia+ T cells. The discussion of this unusual case of Whipple's disease includes — besides possible cellular immunological abnormalities — genetic factors, especially since this patient was HLA-B-27-positive as was his son who is suffering from ankylosing spondylitis.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Pflügers Archiv 410 (1987), S. 75-82 
    ISSN: 1432-2013
    Schlagwort(e): Twitch fibre ; K-contracture ; Inactivation ; D600
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract (1) Single twitch fibres were dissected from tibialis muscles ofRana temporaria and used to study the effect of D600 (gallopamil) on potassium-induced contractures. (2) 95 mM K-Ringer's was applied for 8–15 s at intervals of generally 2.5–5 min; at temperatures of 6–8°C and in the absence of D600 the amplitude of the contractures remained fairly constant. After pretreatment with D600 (30 μM) a single (conditioning) K-contracture was sufficient to ‘paralyze’ the fibres (cf. Eisenberg et al. 1983). (3) Complete paralysis could also be achieved at 18–20°C. In three fibres a single conditioning K-application was sufficient; in two more fibres two or three conditioning K-applications were required. (4) D600-paralysis could not only be achieved with high K-concentrations but also by conditioning with subor suprathreshold K-concentrations (20–40 mM); the duration of the conditioning periods required to induce complete paralysis was approximately the same before and after D600-treatment. (5) Contractures were partially abolished by application of 20–40 mM K-Ringer's for short conditioning periods; after D600-treatment the degree of contracture loss was similar. (6) At low temperature the state of partial or complete paralysis induced by subthreshold K-concentrations and D600 was maintained for long periods of time. (7) The presence of 10 mM Ca2+ did not protect the fibres from being paralyzed by treatment with D600 and high K-Ringer's at low temperature; however, more than one conditioning K-application was required. (8) Resting and action potentials of paralyzed fibres were not significantly different from control values. However, endplate potentials were reduced in size, and failure of neuromuscular transmission was observed in some of these fibres. (9) It is concluded that D600 prolongs the state of inactivation of the contractile mechanism, while the development of inactivation does not seem to be markedly affected.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Pflügers Archiv 412 (1988), S. 390-396 
    ISSN: 1432-2013
    Schlagwort(e): Slow fibre ; K-Contracture ; D600 ; Inactivation ; Repriming
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract (1) The effect of 30 μM D600 on the amplitude and time course of isometric contractures was studied in single slow fibres ofRana temporaria. (2) D600 only slightly reduced the amplitude of contractures evoked with 30 or 95 mM K-Ringer's. Maintenance of tension was strongly impaired by D600 only during exposure to 95 mM K. The caffeine contracture was not affected. (3) Addition of 10 mM Ca2+ or other divalent cations to the medium strongly counteracted the effect of D600 on maintained tension. The order of efficiency was Ca2+=Ni2+〉Co2+〉Mn2+〉Mg2+. (4) During 2 min exposure to 95 mM K-Ringer's the slow fibres inactivated to a variable degree; recovery from inactivation in normal Ringer's proceeded with a half time of the order of 1 min, while in the presence of D600 recovery was prolonged 3.3 to 27 times. (5) It is concluded that the effect of D600 on the contractile behaviour of slow fibres fromRana temporaria is predominantly due to a prolongation of the inactivated state. It is suggested that D600 binds to a site at the outer membrane surface which also binds divalent cations and determines the degree of contractile inactivation during exposure to potassium. Blocking of Ca2+ channels is unlikely to be the mechanism of this D600-effect.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Der Pathologe 16 (1995), S. 404-407 
    ISSN: 1432-1963
    Schlagwort(e): Schlüsselwörter Nerval-neuroendokriner Komplex ; Zollinger-Ellison-Syndrom ; Magenschleimhaut ; Elektronenmikroskopie ; Key words Nerve fibre-neuroendocrine cell complex ; Stomach ; Zollinger-Ellison-Syndrom ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Beschreibung / Inhaltsverzeichnis: Summary Nerve fibre-neuroendocrine cell complexes (NF-NEC-C's) are neuroendocrine cells located in the lamina propria of the gastrointestinal tract directly connected with nerve fibres of Meissner's plexus. We report on a patient with sporadic Zollinger-Ellison syndrome (ZES) with electron microscopically demonstrated multiple NF-NEC-C's in non-antral gastric mucosa. It is suspected that in ZES the hypergastrinaemia may represent a trophic stimulus for the proliferation of NF-NEC-C's in the gastric mucosa.
    Notizen: Zusammenfassung Unter nerval-neuroendokrinen Komplexen (N-NE-K) versteht man in der Lamina propria mucosae des Magen-Darm-Traktes gelegene Nester neuroendokriner Zellen, die in direktem Kontakt zu Nervenfasern des Meissner-Plexus stehen. Es wird über einen Patienten mit sporadischem Zollinger-Ellison-Syndrom (ZES) berichtet, bei dem sich elektronenmikroskopisch in nonantraler Magenschleimhaut multiple N-NE-K fanden. Möglicherweise stellt die Hypergastrinämie bei ZES einen trophischen Stimulus für die Proliferation von N-NE-K in der Magenschleimhaut dar.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Journal of cancer research and clinical oncology 105 (1983), S. 285-291 
    ISSN: 1432-1335
    Schlagwort(e): Borderline lesion ; Severe dysplasia ; Gastric precancerosis ; Electron microscopy ; Morphometric analysis ; Bleb formation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The “borderline lesion” of the stomach (severe dysplasia of the protruded type) is nowadays considered to be a true precancerous lesion. Histologically, this lesion is characterized by a proliferation in the area of the glandular neck, combined with severe cellular atypia. Investigation by means of transmission electron microscopy reveals the structure of these cells to be very similar to the structure of cells of an intestinal-cell-type carcinoma of the stomach. In addition to signs for a loss of differentiation of the cells, such as the absence of rough-surfaced endoplasmatic reticulum, mucin granules, and of the polarity of the cells, remarkably frequently luminal bulges and “blebs” developed to various extents can be detected. Morphometric analysis is delineating the tendency of structural features of the borderline lesion to develop toward the gastric cancer cell. These irregularities might be expressions of the beginning of expansive growth and signs pointing to differentiation into malignant neoplasia.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Journal of sol gel science and technology 8 (1997), S. 927-929 
    ISSN: 1573-4846
    Schlagwort(e): organic-inorganic hybrids ; sol-gel ; photochromic performance ; spirooxazine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Organic-inorganic hybrid materials synthesized via sol-gel processing are excellent solid matrices for photochromic dyes like spirooxazine, and the photochromic performance can be further enhanced by introducing suitable additives. This work describes the effects of additives on the photochromic intensity (Δ A 0), decolouration rate (k) and photostability of spirooxazine in sol-gel derived organic-inorganic hybrid matrices. They include fluoro-alkylsilane (FAS), bisphenol A (BPA) and methyl-imidazole (MI). FAS enhances both Δ A 0 and photostability, but has little effect on k. The higher the content of BPA, the higher the Δ A 0 and the higher the photostability, but the lower the k. The effect of MI on Δ A 0 and k is not so considerable as that of BPA and is a little complicated, while significant improvement in photostability is achieved by the addition of MI at an optimum concentration with the presence of BPA at a higher content.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Journal of sol gel science and technology 8 (1997), S. 927-929 
    ISSN: 1573-4846
    Schlagwort(e): organic-inorganic hybrids ; sol-gel ; photochromic performance ; spirooxazine
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract Organic-inorganic hybrid materials synthesized via sol-gel processing are excellent solid matrices for photochromic dyes like spirooxazine, and the photochromic performance can be further enhanced by introducing suitable additives. This work describes the effects of additives on the photochromic intensity (ΔA 0), decolouration rate (k) and photostability of spirooxazine in sol-gel derived organic-inorganic hybrid matrices. They include fluoroalkylsilane (FAS), bisphenolA (BPA) and methyl-imidazole (MI). FAS enhances both ΔA 0 and photostability, but has little effect onk. The higher the content of BPA, the higher the ΔA 0 and the higher the photostability, but the lower thek. The effect of MI on ΔA 0 andk is not so considerable as that of BPA and is a little complicated, while significant improvement in photostability is achieved by the addition of MI at an optimum concentration with the presence of BPA at a higher content.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 8
    Digitale Medien
    Digitale Medien
    Springer
    Journal of sol gel science and technology 3 (1994), S. 189-197 
    ISSN: 1573-4846
    Schlagwort(e): nanocomposites ; sol-gel ; heteropolymetalates ; photochromics ; electrochemical properties
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie
    Notizen: Abstract New nanocomposites materials have been synthesized. They present electrochemical and photochromic properties. They are based on a hybrid organic-inorganic network, in which tungsten heteropolyoxometalates (PW12O 40 3− , SiW12O 40 4− , W10O 32 4− , polymeric tungstate) are entrapped. High tungsten ratios could be reached and films or bulk materials have been obtained. The structure of these materials is described on the basis of multi-spectroscopic investigations (IR, EPR, NMR). Electrochemical redox reactions have been observed in thin films. Dark blue reversible coloration of the materials is obtained under UV irradiation. The photochromic mechanism has been investigated and shows the reversible formation of carbonyl group.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 9
    Digitale Medien
    Digitale Medien
    Springer
    The journal of membrane biology 112 (1989), S. 185-192 
    ISSN: 1432-1424
    Schlagwort(e): slow fiber ; K contracture ; D600 ; divalent cations ; competitive binding
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Chemie und Pharmazie
    Notizen: Summary Single, slow muscle fibers fromRana temporaria were equilibrated in normal Ringer's. 95 mmol/liter K1-solution containing various concentrations of Ca2+, Ni2+, Mn2 or Mg2+ was applied, and the ensuing contractures were recorded isometrically. While peak tension (F max) was little affected, maintained tension (measured 1 min after onset of contracture) strongly depended on the concentration and species of divalent cations. Tension was maintained at its peak value in the presence of all species of divalent cations provided their concentrations were adequately increased. Dose-response curves were hyperbolic: Lineweaver-Burk plots revealed straight lines with different slopes intersecting near 1/F max, and indicating the following order of efficiency: Ni2+〉Ca2+〉Mn2+〉〉Mg2+. Hill plots for these cations resulted in straight lines with slopes near 1. Qualitatively similar relationships were obtained with contracture solutions containing D6000 (3–12 μmol/liter). However, under these conditions higher concentrations of Ca2+ or Ni2+ were required in order to fully maintain tension. After a step concentration change in the medium during contracture, the effects of Ca2+ or D600 were detectable only after a delay of 9 and 18 sec, respectively. It is concluded that divalent cations and D600 compete for the same binding site according to a 1:1 reaction. This site is presumably located inside the transverse tubular system and controls inactivation of the contractile force.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 10
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    Advanced Materials for Optics and Electronics 7 (1997), S. 123-133 
    ISSN: 1057-9257
    Schlagwort(e): nanocomposites ; sol-gel ; heteropolymetallates ; photochromics ; holographic data storage ; amplitude grating ; two-wave-mixing recording ; Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Elektrotechnik, Elektronik, Nachrichtentechnik , Physik
    Notizen: This paper describes the properties of some new organic-inorganic photochromic layers. They are based on a hybrid organic-inorganic matrix in which tungsten heteropolyoxometallates (SiW12O4-40, PW12O3-40) are entrapped in a network obtained from the reaction of 3-glycidoxy-propyltrimethoxysilane. The high homogeneity of these materials on the nanoscale leads to transparent monoliths and layers of controlled thicknesses up to 40 μm. The optical properties of the blend are emphasised and the construction of amplitude gratings in the materials by two-wave-mixing experiments is described. The results of the optical experiments and the comparison with the theoretical background are used as a model for photochromic holographic storage processes. © 1997 John Wiley & Sons, Ltd.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...