Thomas Frenzel

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Gd-Ethoxybenzyl-DTPA (Gd-EOB-DTPA) is a highly water-soluble paramagnetic contrast agent. Due to its protein binding of about 10% and its lipophilic residue, Gd-EOB-DTPA exhibits both renal (30% of the dose) and hepatobiliary (70%) excretion in rats. Despite its lipophilic character, the compound displays a low toxicity (LD50 = 7.5 mmol/kg). T1-relaxivity(More)
OBJECTIVES In this prospective preclinical study, we evaluated T1-weighted signal intensity in the deep cerebellar nuclei (CN) and globus pallidus (GP) up to 24 days after repeated administration of linear and macrocyclic gadolinium-based contrast agents (GBCAs) using homologous imaging and evaluation methods as in the recently published retrospective(More)
BACKGROUND AND PURPOSE The hyperintense acute reperfusion marker (HARM) on fluid-attenuated inversion recovery MRI is believed to be caused by gadolinium-based contrast agents crossing a disrupted blood-brain barrier. However, this hypothesis has never been directly verified in humans. METHODS In this study, we analyzed cerebrospinal fluid samples of(More)
A new lanthanide complex, praseodymium-2-methoxyethyl-DO3A, was tested as a temperature indicator for 1H magnetic resonance spectroscopy under in vivo conditions, using a 2-T imaging system. The chemical shift of the methoxy group of the compound is strongly temperature dependent. In vitro, a shift change of -0.131 ppm/degree C was found. The signal was(More)
OBJECTIVE To develop and characterize a clinically applicable, fast and efficient method for stem cell labeling with ferucarbotran and protamine for depiction with clinical MRI. METHODS The hydrodynamic diameter, zeta potential and relaxivities of ferucarbotran and varying concentrations of protamine were measured. Once the optimized ratio was found,(More)
This paper evaluates the performance of QoS-aware Mobile IP Fast Authentication Protocol (QoMIFA) compared to the well-known Simple QoS signaling protocol (Simple QoS) via simulation studies mod-eled in the ns2. The evaluation comprises the investigation of network load impact on both protocols with respect to the time required to reserve resources, number(More)
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