414 research outputs found

    Bedeutung molekularpathologischer Methoden in der Onkologie: Pathologie und onkologische Entscheidungsprozesse

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    Zusammenfassung: Die Anzahl von molekularen Untersuchungen in der Histo- und Zytopathologie hat in den letzten Jahren, insbesondere mit zunehmender Bedeutung der sog. personalisierten Medizin bei Krebspatienten, stark zugenommen. Die Ergebnisse dieser Untersuchungen fließen vermehrt in die Pathologieberichte ein, die den behandelnden Ärzten als Grundlage fĂŒr weitere Therapieentscheidungen dienen. Die wichtigsten molekularen Methoden, die derzeit in der Pathologie eingesetzt werden, werden mit ihren Möglichkeiten und Grenzen vorgestell

    Bedeutung molekularpathologischer Methoden in der Onkologie: Pathologie und onkologische Entscheidungsprozesse

    Get PDF
    Zusammenfassung: Die Anzahl von molekularen Untersuchungen in der Histo- und Zytopathologie hat in den letzten Jahren, insbesondere mit zunehmender Bedeutung der sog. personalisierten Medizin bei Krebspatienten, stark zugenommen. Die Ergebnisse dieser Untersuchungen fließen vermehrt in die Pathologieberichte ein, die den behandelnden Ärzten als Grundlage fĂŒr weitere Therapieentscheidungen dienen. Die wichtigsten molekularen Methoden, die derzeit in der Pathologie eingesetzt werden, werden mit ihren Möglichkeiten und Grenzen vorgestell

    Evidence for multiple superconducting gaps in optimally doped BaFe1.87_{1.87}Co0.13_{0.13}As2_{2} from infrared spectroscopy

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    We performed combined infrared reflection and ellipsometry measurements of the in-plane optical reponse of single crystals of the pnictide high temperature superconductor BaFe1.87_{1.87}Co0.13_{0.13}As2_{2} with TcT_{c} = 24.5 K. We observed characteristic superconductivity-induced changes which provide evidence for at least three different energy gaps. We show that a BCS-model of isotropic gaps with 2Δ/kBTc\Delta/k_{B}T_{c} of 3.1, 4.7, and 9.2 reproduces the experimental data rather well. We also determine the low-temperature value of the in-plane magnetic penetration depth of 270 nm

    Recurrent phosphaturic mesenchymal tumour of the temporal bone causing deafness and facial nerve palsy

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    Abstract Objective: We describe the first reported case of a phosphaturic mesenchymal tumour, mixed connective tissue variant, invading the temporal bone. Case report: A female patient presented with increasing deafness. On examination there appeared to be a mass behind an intact tympanic membrane. Further radiological investigation showed a vascular mass occupying the middle ear, mastoid and internal auditory meatus. This was surgically resected and revealed to be a benign phosphaturic mesenchymal tumour, mixed connective tissue variant. The tumour recurred a year later, presenting as facial nerve palsy. A revision procedure was carried out; the tumour was excised with the sacrifice of a segment of the facial nerve, and a facial-hypoglossal nerve anastomosis was performed. Conclusion: This case report highlights the occurrence of this benign but sometimes aggressive tumour, of which both clinicians and pathologists should be aware. Early recognition of the condition remains of utmost importance to minimise the debilitating consequences of long-term osteomalacia in affected patients, and to prevent extracranial and intracranial complications caused by the tumou

    LRRML: a conformational database and an XML description of leucine-rich repeats (LRRs)

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    Background: Leucine-rich repeats (LRRs) are present in more than 6000 proteins. They are found in organisms ranging from viruses to eukaryotes and play an important role in protein-ligand interactions. To date, more than one hundred crystal structures of LRR containing proteins have been determined. This knowledge has increased our ability to use the crystal structures as templates to model LRR proteins with unknown structures. Since the individual three-dimensional LRR structures are not directly available from the established databases and since there are only a few detailed annotations for them, a conformational LRR database useful for homology modeling of LRR proteins is desirable. Description: We developed LRRML, a conformational database and an extensible markup language (XML) description of LRRs. The release 0.2 contains 1261 individual LRR structures, which were identified from 112 PDB structures and annotated manually. An XML structure was defined to exchange and store the LRRs. LRRML provides a source for homology modeling and structural analysis of LRR proteins. In order to demonstrate the capabilities of the database we modeled the mouse Toll-like receptor 3 (TLR3) by multiple templates homology modeling and compared the result with the crystal structure. Conclusion: LRRML is an information source for investigators involved in both theoretical and applied research on LRR proteins. It is available at http://zeus.krist.geo.uni-muenchen.de/similar to lrrml

    Macroscopic phase segregation in superconducting K0.73Fe1.67Se2 as seen by muon spin rotation and infrared spectroscopy

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    Using muon spin rotation (\muSR) and infrared spectroscopy we investigated the recently discovered superconductor K0.73Fe1.67Se2 with Tc = 32 K. We show that the combined data can be consistently described in terms of a macroscopically phase segregated state with a matrix of ~88% volume fraction that is insulating and strongly magnetic and inclusions with a ~12% volume fraction which are metallic, superconducting and non-magnetic. The electronic properties of the latter, in terms of the normal state plasma frequency and the superconducting condensate density, appear to be similar as in other iron selenide or arsenide superconductors.Comment: 22 pages, 8 figures. (citation list correction.

    Electric-field-induced pyroelectric order and localization of the confined electrons in LaAlO3/SrTiO3 heterostructures

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    With infrared ellipsometry, x-ray diffraction, and electric transport measurements we investigated the electric-field-effect on the confined electrons at the LaAlO3/SrTiO3 interface. We obtained evidence that the localization of the electrons at low temperature and negative gate voltage is induced, or at least strongly enhanced, by a pyroelectric phase transition in SrTiO3 which strongly reduces the lattice polarizability and the subsequent Coulomb screening. In particular, we show that the charge localisation and the polar order of SrTiO3 both develop below about 50 K and exhibit similar, unipolar hysteresis loops as a function of the gate voltage. Our findings suggest that the pyroelectric order also plays an important role in the quantum phase transition at very low temperatures where superconductivity is suppressed by an electric field.Comment: 5 pages, 4 figures, supplementary materia

    Pseudogap and precursor superconductivity in underdoped cuprate high temperature superconductors: A far-infrared ellipsometry study

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    Abstract.: With the technique of infrared ellipsometry we performed a detailed study of the temperature- and doping dependence of the c-axis response of a series of YBa2Cu3O7−ή single crystals. In particular, we explored the anomalous electronic properties at temperatures above the macroscopic superconducting transition temperature, T c, whose conflicting explanations range from a precursor superconducting state to electronic correlations that compete with superconductivity. We show that the c-axis spectra provide evidence that both kinds of correlations are present and that their contributions can be disentangled based on an analysis with a so-called multilayer-model. We find that the onset temperature, T *, and the energy scale, ΔPG, of the competing pseudogap increase rapidly towards the underdoped side whereas they vanish on the overdoped side. In addition, we provide evidence that in a strongly underdoped sample the precursor superconducting correlations develop below an onset temperature, T ons, that is considerably lower than T * but still much higher than T

    Evidence of precursor superconductivity as high as 180 K from infrared spectroscopy

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    We show that a multilayer analysis of the infrared c-axis response of RBa2Cu3O7-d (R=Y, Gd, Eu) provides important new information about the anomalous normal state properties of underdoped cuprate high temperature superconductors. Besides competing correlations which give rise to a pseudogap that depletes the low-energy electronic states below T*>>Tc, it enables us to identify the onset of a precursor superconducting state below Tons>Tc. We map out the doping phase diagram of Tons which reaches a maximum of ~180 K at strong underdoping and present magnetic field dependent data which confirm our conclusions.Comment: 5 pages, 3 figure
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