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Showing 1 to 20 of 23 for “"NMR-Tomographie"”.
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Erweiterte Phasenkodier-Trajektorien für kontinuierliche NMR-Tomographie
Das starre Aufnahmeschema konventioneller 2-dimensionaler Mehrschichtbildgebung verursacht eine unerwünschte wechselseititge Abhängigkeit von Kontrast- und Auflösungsparametern eines MR-Bildes. So ist z.B. die Anzahl der Scheiben, die in einer Messung aufgenommen werden können, durch die …
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Dichte-gewichtete Phasenkodierung zur effizienten k-Raumabtastung in der NMR-Bildgebung
Die spektroskopische NMR-Bildgebung (Chemical Shift Imaging, CSI) kombiniert die Lokalisationstechniken der NMR-Tomographie mit der NMR-Spektroskopie und bietet so eine ortsaufgelöste metabolische Information über das untersuchte Gewebe. Mit dieser Technik können Stoffwechselvorgänge direkt und …
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Convergence of pitch and number word magnitude coding in the intraparietal cortex
The human capability of abstraction enables us to appreciate and process completely different impressions and stimuli. One approach to an abstract association system came from Walsh (Theory of Magnitude, ATOM, 2003). He postulated, that time, space, and quantity are processed by a generalized …
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Funktionsdiagnostik des Herzens mittels Dual-Source-Computertomographie im Vergleich zur Magnetresonanztomographie : eine tierexperimentelle Studie an Schweinen
In cardiac function diagnosis several invasive and non-invasive examination procedures are available. To determine the cardiac volume and pumping function the magnetic resonance imaging (MRI) is considered to be gold standard. Different workgroups have already examined the correlation of …
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Zwei Wege zur Paritätsentscheidung: eine fMRT-Studie zur Notations-/Modalitätsspezifität in der Zahlenverarbeitung
Introduction: According to Dehaene and Cohen (1995) as well as Dehaene et al. (2003), numbers are processed depending on notation, modality and task. Three codes are claimed to build a network of functional and anatomical number representations. First, an abstract semantic magnitude representation …
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Evaluation von Gruppenunterschieden bei fMRI-Daten an einem Beispiel aus der psychiatrischen Forschung
Schizophrenia can be characterized by an impairment in emotional processing. Whereas emotional experience of patients with schizophrenia might function normally, the ability to perceive emotional stimuli is disturbed. The accomplishment to perceive and process emotional facial expressions is …
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MR-tomographische Untersuchungen zur Entwicklung eines verspäteten Hirnödems nach operativer Ausräumung intrazerebraler Blutungen im Schweinemodell
Objectives: Spontaneous intracerebral hemorrhage is associated with high mortality and morbidity. Despite of countless clinical and experimental trials, no evidence-based therapy can be recommended. The therapeutic alternatives include best medical therapy, surgical therapy via craniotomy and lysis …
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Magnetresonanztomographie mit einer 3D-T2-gewichteten Turbo-Spin-Echo-Sequenz unterschiedlicher Auflösung : Darstellung anatomischer Details und pathologischer Veränderungen in axialen Aufnahmen, Maximum-Intensitäts-Projektionen und dreidimensionalen Volumenrekonstruktionen
In the present dissertation a very high-resolution three-dimensional T2-weighted turbo spin-echo sequence (3D-T2-TSE) with a matrix of 230 x 230 pixels was benchmarked in comparison to a highresolution sequence with a matrix of 128 x 128 pixels to the imaging of anatomical structures and …
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Akustisches Synchronisationsverfahren für die Magnetresonanztomographie
In current clinical MR practice, cardiac motion is dealt with using electrocardiographic (ECG) gating to synchronize data acquisition with the cardiac cycle. ECG, being an inherently electrical measurement, is corrupted by interferences with electromagnetic fields and by magnetohydrodynamic …
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Vergleich zweier Kontrastmittel in der kernspintomographischen Vitalitätsdiagnostik des Myokards
Within clinical routine examinations we performed a study containing 60 patients undergoing a 1,5 Tesla MR imaging of cardiac vitality. By using a standardized protocol cine images were gathered by a true-FISP-sequence and late enhancement images with IR turbo-Flash-sequence. Look locker sequences …
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Molecular analysis of the role of Caspase-8 during liver regeneration and tumorigenesis
Binding of the cytokine TNF-alpha to TNF-Receptor 1 mediates pleiotropic effects via two different signaling complexes. Complex-I triggers activation of NF-kappaB and activation of c-Jun N-terminal kinases (JNK) leading to inflammation and/ or cell proliferation, whereas complex-II induces …
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Eine vergleichende Studie zur zerebralen Repräsentation des Spiegelneuronensystems und der Deutschen Gebärdensprache bei Normalprobanden sowie Gehörlosen
The mirror neuron system is an observation-execution matching system activated, in humans, during action observation, motor learning, and imitation of action. Furthermore it is hypothesized that the mirror neuron system plays a key role during the evolution of language and provides the necessary …
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Development and application of techniques for quantitative voxel based morphometry
The use of standard brain atlases is well established in the MR community, but none of the commonly utilised standard brains or atlases, such as MNI305 or ICBM152, provide quantitative information. Within the framework of quantitative MRI of the brain, which has gained much importance in the last …
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Bildgebende Untersuchung zum Erlernen visuell dargebotener Artikulationsmuster
INTRODUCTION: The influence of facial visual articulatory information on the process of speech perception is well-known. On the speech production side midsagittal visual articulatory information is helpful for learning and releraning to produce speech sounds, syllables, or words in speech therapy. …
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Functional networks of within- and cross-modal divided attention
In modern neuropsychology attention is subdivided into different domains (Fernandez-Duque & Posner, 2001; Posner & Boies, 1971; Posner & Rafal, 1987; Sturm, 2005; van Zomeren & Brouwer, 1994). One of these domains is divided attention, which describes the ability to process two or more different …
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Räumliche Orientierung auf dem mentalen Zahlenstrahl : eine kombinierte Reaktionszeit- und fMRT-Studie
Semantic number magnitude is represented in an analogue visual-spacial system in the shape of a left-to-right oriented, logarithmically compressed mental number line; the most important evidence is the SNARC (Spatial Numerical Association of Response Codes)-effect (Dehaene, Bossini & Giraux, 1993). …
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Vergleich zweier MRT-Kontrastmittel mit unterschiedlicher T1-Relaxivität zur Gefäßdarstellung bei Patienten mit abdominellen Aortenaneurysmen
The aim of this tripartite work is the comparison of different paramagnetic contrast agents in the examination of the infrarenal arterial vascular tree in magnetic resonance imaging (MRI) at 1.5 T in a group of patients with infrarenal aortic aneurysms. The two gadolinium-based contrast agents used …
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MRT-gesteuerte Ballonangioplastie peripherer Arterien zur lokalen Substanzapplikation in die Gefäßwand
Magnetic resonance imaging permits the realisation of vascular interventions by the use of real-time sequences. In order to treat arteriosclerotic vessel lumen stenoses and prevent restenoses after angioplasties local drug-delivery during intervention has been suggested. Within four examination …
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Serotonergic modulation of response inhibition : a fMRI study
In animal and human studies, the neurotransmitter serotonin (5-HT) has been implicated in inhibitory control. Using functional magnetic response imaging (fMRI), the present study investigated the acute effects of pharmacological modulation in the serotonergic system on brain activations during …
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