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61.
Astrid R. R. Heutelbeck Carsten Junghans Hermann Esselmann Ernst Hallier Thomas G. Schulz 《International archives of occupational and environmental health》2009,82(9):1123-1131
Introduction
Cattle are an important source of allergens in the working area of farmers. Asthma caused by cow allergens is a significant occupational problem. Yet in allergological testing, the results of in vivo and in vitro diagnostic tests are often inconsistent even in cases with clearly cattle-related symptoms. 相似文献62.
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64.
Robin M Heidemann Mark A Griswold Nicole Seiberlich Mathias Nittka Stephan A R Kannengiesser Berthold Kiefer Peter M Jakob 《Magnetic resonance in medicine》2007,57(6):1037-1046
MRI with non-Cartesian sampling schemes can offer inherent advantages. Radial acquisitions are known to be very robust, even in the case of vast undersampling. This is also true for 1D non-Cartesian MRI, in which the center of k-space is oversampled or at least sampled at the Nyquist rate. There are two main reasons for the more relaxed foldover artifact behavior: First, due to the oversampling of the center, high-energy foldover artifacts originating from the center of k-space are avoided. Second, due to the non-equidistant sampling of k-space, the corresponding field of view (FOV) is no longer well defined. As a result, foldover artifacts are blurred over a broad range and appear less severe. The more relaxed foldover artifact behavior and the densely sampled central k-space make trajectories of this type an ideal complement to autocalibrated parallel MRI (pMRI) techniques, such as generalized autocalibrating partially parallel acquisitions (GRAPPA). Although pMRI can benefit from non-Cartesian trajectories, this combination has not yet entered routine clinical use. One of the main reasons for this is the need for long reconstruction times due to the complex calculations necessary for non-Cartesian pMRI. In this work it is shown that one can significantly reduce the complexity of the calculations by exploiting a few specific properties of k-space-based pMRI. 相似文献
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Stephan N. W. Dommann 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》1996,47(3):169-172
Zusammenfassung
Adh?sionsmoleküle sind Zell-Oberfl?chen-Proteine, welche verantwortlich sind für die Zell-Zell- und Zell-Matrix-Interaktionen.
Sie sind in der Lage eine gro?e Zahl von Stimuli zu erkennen und darauf entsprechend zu reagieren. Sie bilden somit eine Basis
für manchen physiologischen und pathologischen Prozess insbesonders des „Homing“-Verhaltens, der Homeostase der Immunantwort,
der Wundheilung, der Entzündungen und der Tumormetastasierung. In der Dermatologie wurde das Interesse vor allem durch die
Entdeckung des CLA (cutaneous lymphocyte antigen) geweckt, welches der spezifische „Homing“-Rezeptor für Memory-T-Zellen darstellt.
So konnte gezeigt werden, da? die Zellen in kutanen Lymphomen CLA-positive T-Zellen sind, im Gegensatz zu prim?r nodalen Non-Hodgkin
Lymphomen, wo die T-Zellen CLA negativ sind. Neuere Arbeiten haben gezeigt, da? die Adh?sionsmoleküle wie CD44v6 bei kutanen
Lymphomen, welche eine systemische Ausbreitung zeigen, auf den Tumorzellen exprimiert werden und somit eine entscheidende
Rolle in der Metastasierung dieser Tumoren darstellen.
Eingegangen am 27. November 1995 Angenommen am 22. Dezember 1995 相似文献
68.
Comparative genomic hybridization (CGH) discloses chromosomal and subchromosomal copy number changes in Merkel cell carcinomas 总被引:1,自引:0,他引:1
M. Härle N. Arens I. Moll W. Back T. Schulz H. Scherthan 《Journal of cutaneous pathology》1996,23(5):391-397
We analyzed three Merkel cell carcinomas (MCC), applying comparative genomic hybridization (CGH) with DNA from paraffin-embedded and cultured tumor material as the probes. By this method, numerous changes in chromosome copy numbers were observed in each tumor investigated. Recurrent gains of chromosomes 1, 6, 18q and 20 were detected in two tumors. A third tumor showed complex chromosomal copy number changes, including gain of chromosome 8 and 9. These gains, as well as gain of chromosome 1 in the first two tumors, were confirmed by fluorescence in situ hybridization to paraffin tissue sections. Our results support the view that important genes for MCC development may be located on chromosomes 1, 6, 18q and 20. 相似文献
69.
70.
The ischaemic cerebral attack is a disease prevailingly of older age. Its prognosis is distinguished by a mortality rate as high as ever. From 1975 to 1985, 520 patients with ischaemic cerebral attack have been treated in hospital, with specific acute therapy changing from the so-called vasodilator therapy via osmotherapy into haemodilution therapy with lowmolecular dextrane. Since during vasodilator therapy any early mobilisation nor continuous physiotherapy were carried out and the patients prevailingly died of bronchopneumonia, the significantly lower mortality rate under osmotherapy and haemodilution therapy cannot be attributed to the specific drug therapy. In all probability it is a result of the improvement of care and of the active early mobilisation of the patients. 相似文献