Bibliothek

X
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
  • Inorganic Chemistry  (19)
  • Cell & Developmental Biology  (5)
  • EPR  (2)
  • 1
    Digitale Medien
    Digitale Medien
    Electron Paramagnetic Resonance of Tb3+ Ions in YBa2Cu3O6 (2000)
    Springer
    Journal of superconductivity 13 (2000), S. 895-897 
    Details
    ISSN: 1572-9605
    Schlagwort(e): EPR ; YBCO ; rare-earth ions ; impurities
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Elektrotechnik, Elektronik, Nachrichtentechnik , Physik
    Notizen: Abstract The first observation of electron paramagnetic resonance (EPR) of Tb3+ doped into YBa2Cu3O6 is reported. EPR is used to determine the local symmetry of the rare-earth ion and to study the effect of suppression of high-T c superconductivity by doping. The distance between the lowest singlets of Tb3+ ion Δ ≅ 7.1 GHz ≡ 0.24 cm−1 and g-factor g ∥ ≃ 17.9 have been estimated from measurements. Both these parameters are in a good agreement with the corresponding calculated values. No evidence of Tb4+ ions was found.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1026477519347
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 2
    Digitale Medien
    Digitale Medien
    Tilting Mode Relaxation and Oxygen Isotope Effect in La2−xSrxCuO4 Studied by Electron Paramagnetic Resonance (2000)
    Springer
    Journal of superconductivity 13 (2000), S. 955-958 
    Details
    ISSN: 1572-9605
    Schlagwort(e): EPR ; LSCD ; isotope effect
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Elektrotechnik, Elektronik, Nachrichtentechnik , Physik
    Notizen: Abstract The electron paramegnetic resonance (EPR) of Mn2+ doped into La2−x Sr x CuO4 was used to probe the copper spin relaxation via the bottleneck effect for oxygen isotope (16O and 18O)–substituted samples. It was found that the EPR linewidth is larger for the 18O isotope samples than for the 16O samples. For x = 0.03, the linewidth for the 18O sample is larger than for 16O sample by a factor of 2. The isotope effect is pronounced at low temperatures and decreases with increasing Sr concentration. This effect is quantitatively explained by the Cu2+ S = 1/2 spin relaxation to the lattice via Dzyaloshinski terms coupled linearly to the local Q 4/Q 5 tilting modes of the CuO6 octahedra as proposed by Kochelaev et al. [1] The Q 4/Q 5 modes are coupled sterically to the Q 2 Jahn–Teller modes considered to be relevant for the (bi)-polaron formation and thus for the high-temperature superconductivity (HTSC).
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1023/A:1026498123890
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 3
    Digitale Medien
    Digitale Medien
    Colchicine-induced stimulation of PMN motility related to cytoskeletal changes in actin, α-actinin, and myosin (1993)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 25 (1993), S. 10-18 
    Details
    ISSN: 0886-1544
    Schlagwort(e): microtubules ; blebs ; locomotion ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Colchicine-induced stimulation of polymorphonuclear leukocyte (PMN) locomotion is an interesting model because extension of blebs at the front occurs at a rate (about 2.4 μm/s) which is far above that reported for growth of actin filaments. The following cytoskeletal changes were observed in colchicine-treated PMNs: (1)a small increase in cytoskeleton-associated actin was noted, as well as a somewhate more pronounced increase in cytoskeleton-associated α-actinin, as compared with untreated or DMSO-treated controls. There was, however, no measurable increase in F-actin as determined by NBD-phallacidin blinding; (2)the values for the ratio (α-actinin/actin) are lower in PMNs treated with colchicine for 30 min, as compared with PMNs stimulated with fNLPNTL for 1 minute (non-polar ruffling cells) or 30 min (polarized locomoting cells); thus, this ratio may depend on the type of PMN motility; (3) in polarized PMNs F-actin was mainly located linearly all along the cell membrane; there was more intense staining at the front of the cells; (4) α-actining appeared to colocalize with F-actin at the leading front, but not with F-actin at the tail of polarized cells; (5) myosin was preferentially found at the rear part of polarized cells but not or only to a small extent at the front. Our data indicate a close functional correlation between microtubules and microfilaments. We speculate that F-actin in combination with α-actinin promotes expansion of pseudopods, whereas myosin combined with F-actin promotes contraction. In more general terms we suggest that different forms of PMN motility are generated by differential selective interaction of cytoskeletal compnents and variations in the composition of the cytoskeleton in different sites of the same cells. © 1993 Wiley-Liss, Inc.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/cm.970250103
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 4
    Digitale Medien
    Digitale Medien
    Motility, cell shape, and locomotion of neutrophil granulocytes (1983)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 3 (1983), S. 47-60 
    Details
    ISSN: 0886-1544
    Schlagwort(e): neutrophil granulocytes ; motility ; locomotion ; cell-shape ; cell-substratum adhesion ; f-Met-Leu-Phe ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Activation of the motile apparatus by chemokinetic factors cannot be reliably assessed in cells that are attached to a solid substratum because motility can be totally abolished by excessive adhesion. It is however, necesary to quantify the activation of the motile apparatus in order to analyze and understand chemokinetic responses.It was the purpose of the present work to establish morphological criteria that can be used to quantify motility in nonadherent (floating) neutrophils and to predict the locomotor response under conditions of limited adhesion. The proportion of neutrophils performing crawling-like movements (polarized cells) in suspension correlates very closely with stimulated locomotion at low to optimal concentration of f-Met-Leu-Phe, ie, under conditions of limited adhesion. Reduced locomotion at supraoptimal concentrations of f-Met-Leu-Phe has also morphological correlates. The major feature is the decrease in the proportion of neutrophils performing crawling-like movements and the corresponding appearance of cells that are motile but not polarized in suspension and that do not locomote on the substratum. Concentration-dependent changes in neutrophil length and in the proportion of polarized neutrophils with and without tail were also observed. The locomotor potential of neutrophils under conditions of limited contact with the substratum can be predicted on the basis of their motile behavior, in particular the proportion of cells showing crawling-like movements, in suspension. In combination with measurements of adhesion the procedure should permit a more complete analysis of the regulation of chemokinetic responses.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/cm.970030105
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 5
    Digitale Medien
    Digitale Medien
    Orthokinetic and klinokinetic responses of human polymorphonuclear leucocytes (1985)
    New York, NY : Wiley-Blackwell
    Cell Motility and the Cytoskeleton 5 (1985), S. 447-461 
    Details
    ISSN: 0886-1544
    Schlagwort(e): chemokinesis ; orthokinesis ; klinokinesis ; polymorphonuclear leucocytes ; locomotion ; Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Evidence is presented to show that klinokinesis, which was previously demonstrated in bacteria and amoeba only, may also occur in metazoan cells. The chemotactic peptide formyl-Met-Leu-Phe (fMLP) elicited orthokinetic and klinokinetic responses of human blood-borne polymorphonuclear leucocytes (PMNs) under the test conditions used. Increased speed (orthokinesis) was due to an increase in the proportion of migrating cells as well as in the speed of the locomoting subset. The klinokinetic effect was manifested by a decrease in the klinolocomotion index, the mean angle of changes in direction ≥ 90°, and the frequency of turns ≥ 90°. The klinolocomotion index was inversely related to speed. This explains the synergistic effect of klinokinesis and orthokinesis in this system. Colchicine alone had and orthokinetic effect which was exclusively due to alterations in the proportion of migrating cells and it altered the turning behaviour without exerting a klinokinetic effect. However, colchicine had marginal orthokinetic and klinokinetic effects on fMLP-stimulated cells resulting in reduced translocation. The relationship between klinokinesis and mean angle or frequency of turns has been analysed. Klinokinesis was a substantial though not the major element of the chemokinetic response to fMLP under the conditions used. No other metazoan cells have been shown to possess such a complete pattern of responses, including orthokinesis, klinokinesis, and chemotaxis, which regulate locomotion.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/cm.970050603
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 6
    Digitale Medien
    Digitale Medien
    Diacylglycerols and PMA are particularly effective stimulators of fluid pinocytosis in human neutrophils (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 145 (1990), S. 465-471 
    Details
    ISSN: 0021-9541
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Diacylglycerols (OAG, diC8) and PMA were found to stimulate fluid pinocytosis (net uptake of FITC-dextran) to a far greater extent than other neutrophil activators, such as the chemotactic agents fNLPNTL and LTB4, the microtubule disassembling agents colchicine and nocodazole, the kinase inhibitor H-7, or D2O. OAG and diC8 produce a dose-dependent increase in the uptake of FITC-dextran, which is up to about 25- to 30-fold the control value of unstimulated neutrophils. The protein kinase inhibitor H-7 alone had a small stimulating effect on the net uptake, and it failed to inhibit stimulation of fluid pinocytosis by PMA, OAG, and diC8. Also, the protein kinase inhibitor staurosporine failed to inhibit fluid pinocytosis stimulated by OAG, diC8, and PMA. Stimulated fluid pinocytosis and vacuolization in response to PMA or diacylglycerols is associated with surface ruffling of neutrophils. Pinocytosis as well as surface ruffling stimulated by PMA, OAG, diC8, or diC10 are suppressed in the presence of cytochalasin D. The results suggest that diacylglycerols may be instrumental in transducing the signal for stimulated pinocytosis and that the surface movements induced by diacylglycerols, and PMA may be instrumental in fluid pinocytosis.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jcp.1041450311
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 7
    Digitale Medien
    Digitale Medien
    Selective effects of the PKC inhibitors Ro 31-8220 and CGP 41 251 on PMN locomotion, cell polarity, and pinocytosis (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 161 (1994), S. 526-536 
    Details
    ISSN: 0021-9541
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Using two newly synthesized inhibitors, Ro 31-8220 and CGP 41 251, of protein kinase C (PKC), we analyzed: (1) how distinct PMN functions (shape changes, locomotion, pinocytosis) are regulated, and (2) the role of protein phosphorylation and PKC in this process. We were able to transform: (1) resting PMNs into locomoting cells using fNLPNTL, (2) locomoting cells into non-locomoting highly pinocytic cells using PMA, and (3) PMA-stimulated cells showing marked pinocytosis into locomoting or into resting cells using Ro 31-8220. It is thus possible to selectively manipulate PMN function (resting state, locomotion, marked pinocytosis), indicating that there are different regulatory pathways. It was not possible to induce locomotion and marked pinocytosis simultaneously, indicating crosstalk between pathways. Ro 31-8220 inhibited PMA-induced shape changes (nonpolar cells) and pinocytosis, but not fNLPNTL-induced shape changes (polarity) and pinocytosis. At higher concentrations, Ro 31-8220 alone elicited cell polarity and chemokinesis, indicating that a constitutively active protein kinase is involved in maintaining the spherical shape of resting PMNs. Functional effects of another PKC inhibitor, CGP 41 251, on neutrophil function were strikingly different. CGP 41 251 selectively inhibited fNLPNTL-induced polarity and locomotion (but not colchicine or Ro 31-8220-induced polarity), and it failed to inhibit PMA-induced, stimulated pinocytosis and shape changes. Although the effects of Ro 31-8220 vs. CGP 41 251 on PMN function were strikingly different, the inhibition of profiles for constitutive and for fNLPNTL- or PMA-induced protein phosphorylation in intact PMNs showed only small differences, which could not yet be conclusively related to cell function. © 1994 Wiley-Liss, Inc.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/jcp.1041610316
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 8
    Digitale Medien
    Digitale Medien
    Ag2PdCl4, Kristallstruktur und die kristallchemische Beziehung zum NaCl-Typ (1988)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 562 (1988), S. 123-130 
    Details
    ISSN: 0044-2313
    Schlagwort(e): Chemistry ; Inorganic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Ag2PdCl4, Crystal Structure and the Crystal Chemical Relation to the NaCl TypeAg2PdCl4 single crystals show orthorhombic symmetry with the space group Cmca (No. 64) and the lattice parameters a = 10.088(2), b = 8.051(5), c = 8.078(2) å, with 4 formular units per unit cell. The atomic arrangement of Ag2PdCl4 is explored by X-ray crystal structure analysis.Silver shows a distorted octahedral arrangement of chlorine atoms. Palladium forms typical, approximately square-planar PdCl4 groups. Ag2PdCl4 is a new variant of a partially occupied sodium chloride structure type.
    Notizen: Die Kristallstruktur von Ag2PdCl4 wurde mit röntgenographischen Methoden an Einkristallen ermittelt. Ag2PdCl4 kristallisiert mit orthorhombischer Symmetrie: Cmca (No. 64), a = 10,088(2), b = 8,051(5), c = 8,078(2) å mit 4 Formeleinheiten pro Elementarzelle.Silber besitzt eine verzerrt oktaedrische Chlor-Nachbarschaft, während das Palladium annähernd quadratisch planare PdCl4-Gruppen bildet. Ag2PdCl4 stellt eine neue Variante einer teilbesetzten Natriumchloridstruktur dar.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/zaac.19885620115
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 9
    Digitale Medien
    Digitale Medien
    Die Kristallstruktur von AgPb4O4CI, eine kuriose Variante des Blei(II)-oxid-Strukturtyps (1988)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 566 (1988), S. 62-70 
    Details
    ISSN: 0044-2313
    Schlagwort(e): Chemistry ; Inorganic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Crystal Structure of AgPb4O4Cl, a Curious Variant of the Tetragonal Structure Type of PbOAgPb4O4Cl was prepared for the first time and the crystal structure was explored by single crystal measurement. The compound crystallizes with tetragonal symmetry in space group P4/n - No. 85 with a = 8.197(2) Å, c = 6.257(4) Å and two formulae per unit cell. The structure was refined by full matrix least-squares techniques to an R value of 0.049. AgPb4O4Cl shows a typical layer structure. Layers of Pb2+, Ag+ and O2- are separated by chloride layers. The crystal-chemical relations to the structural arrangement of the tetragonal modification of PbO is shown.
    Notizen: AgPb4O4Cl wurde erstmalig dargestellt und die Kristallstruktur an Einkristallen aufgeklärt. AgPb4O4Cl kristallisiert tetragonal (Raumgruppe P4/n - No. 85) mit a = 8,197(2) Å, c = 6,257(4) Å und Z = 2. Die Verfeinerung der Einkristallmessung mittels der Methode der kleinsten Fehlerquadrate ergab den Gütefaktor Rw = 0.049. AgPb4O4Cl zeigt eine Schichtstruktur, wobei Chloridionen die Schichten aus Pb2+, Ag+ und O2- trennen. Die kristallchemische Beziehung zum Aufbau der tetragonalen Modifikation von PbO wird dargelegt.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/zaac.19885660109
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 10
    Digitale Medien
    Digitale Medien
    Trigonal-planare CuX3-Gruppen in Cu2Mo6X14, X = Cl, Br, IProfessor Herbert Jacobs zum 60. Geburtstag gewidmet (1996)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 622 (1996), S. 663-669 
    Details
    ISSN: 0044-2313
    Schlagwort(e): Dicopper(I)-octa-μ3-halogeno-hexahalogeno-octahedro-hexamolybdate(II) ; crystal structure ; Mo6X14-group ; trigonal planar CuX3-group ; ionic conduction ; Chemistry ; Inorganic Chemistry
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Beschreibung / Inhaltsverzeichnis: Trigonal Planar CuX3-Groups in Cu2Mo6X14, X = Cl, Br, ICu2Mo6Cl14 (I), Cu2Mo6Br14 (II) and Cu2Mo6I14 (III) were synthesized by thermal treatment of corresponding mixtures of copper(I) and molybdenum(II) halides. The crystal structures were determined by single crystal X-ray analyses. I and II show isotypism, cubic, Pn3 (no. 201, sec. setting), Z = 4, I: a = 12.772(3) Å, II: a = 13.350(2) Å. III shows a new structural type, orthorhombic, Pbca (No. 61), Z = 4, a = 16.058(3) Å, b = 10.643(2) Å, c = 16.963(3) Å. Trigonal planar CuX3 units were found in I—III. Structural behaviour relations are discussed, especially with regard to ionic conductivity.
    Notizen: Cu2Mo6Cl14 (I), Cu2Mo6Br14 (II) und Cu2Mo6I14 (III) wurden durch thermische Behandlung der Gemenge der binären Halogenide CuX und Mo6X12 im molaren Verhältnis 2:1 in einkristalliner Form erhalten. Röntgenographische Strukturbestimmung wurde an Einkristallen durchgeführt. I und II zeigen Isotypie, Pn3 (Nr. 201, sec. setting) Z = 4, I: a = 12,772(3) Å, II: a = 13,350(2) Å. III weist eigenen Strukturtyp auf: Pbca (Nr. 61), Z = 4, a = 16,058(3) Å, b = 10,643(2) Å, c = 16,963(3) Å. In I—III liegen trigonal planare CuX3-Gruppen vor. Bindungsverhältnisse und Meßergebnisse der Ionenleitfähigkeit werden diskutiert.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/zaac.19966220415
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...