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61.
E. Werner P. Roth U. Heinrichs A. Giussani M. C. Cantone Th. Zilker 《Isotopes in environmental and health studies》2013,49(2):123-132
Abstract Although molybdenum is considered to be an essential trace metal for humans, the knowledge about its metabolism is rather limited. The present study was aimed at the assessment of biokinetics following intravenous injection of trace amounts of 95Mo or 96Mo into five healthy volunteers. In a total of 11 investigations, the plasma clearance up to eight hours and the urinary excretion for at least three days after the injection were evaluated. The tracer concentrations were determined by proton nuclear activation analysis in blood plasma and by thermal ionization mass spectrometry in urine samples respectively. In all subjects, the plasma clearance is much faster than expected from the literature. The data obtained for the plasma clearance of the tracer can reasonably be fitted by a two exponential equation. The half times of the fast component range between 4 and 70 minutes and for the slow component between 3 and 30 hours. The urinary excretion of the injected tracer seems also to be faster than expected and the fractions lost are higher for larger doses administered. For the smallest dose given, 34% of the injected tracer were excreted within one day whereas for the four times larger dose about 60% were lost. These findings on urinary excretion are in agreement with recently published results. 相似文献
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Karcher Wolfgang Roth Stefan Spodarev Evgeny Walk Corinna 《Statistical Inference for Stochastic Processes》2019,22(2):263-306
Statistical Inference for Stochastic Processes - Given a low frequency sample of an infinitely divisible moving average random field $$\{\int _{\mathbb {R}^d} f(x-t)\varLambda (dx); \ t \in \mathbb... 相似文献
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Uwe Gaitzsch Hansjörg KlaußStefan Roth Ludwig Schultz 《Journal of magnetism and magnetic materials》2012,324(4):430-433
A 5M Ni-Mn-Ga single crystal was investigated, supplied by Adaptamat Ltd, Finland. Especially low temperature magnetic actuation as well as cyclic tensile-compression tests revealed promising properties, which provide useful insights for training concepts in polycrystalline materials. Successive compressions lead to a significant reduction of the twinning stress by a factor of two. 相似文献
67.
Michelle Hampson Naomi Driesen Jennifer K. Roth John C. Gore R. Todd Constable 《Magnetic resonance imaging》2010
Functional brain imaging studies have identified a set of brain areas typically activated during cognitive tasks (task-positive brain areas) and another set of brain areas typically deactivated during cognitive tasks (task-negative brain areas). Negative correlations, or anticorrelations, between task-positive and task-negative brain areas have been reported at rest. Furthermore, the strength of these anticorrelations appears to be related to cognitive function. However, studies examining anticorrelations have typically employed global regression or similar analysis steps that force anticorrelated relationships to exist between brain areas. Therefore the validity of these findings has been questioned. Here we examine anticorrelations between a task-negative region in the medial frontal gyrus/anterior cingulate cortex and dorsolateral prefrontal cortex, a classic task-positive area, using an analysis that does not include global regression. Instead, we control for whole-brain correlations in the group-level analysis. Using this approach, we demonstrate that the strength of the functional connection between the medial frontal cortex and the dorsolateral prefrontal cortex is related to cognitive function and that this relationship is not an artifact of global regression. 相似文献
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Juan Saulo Gonzlez‐Gonzlez Itzia I. Padilla‐Martínez Efrn V. García‐Bez Olivia Franco‐Hernndez Francisco J. Martínez‐Martínez 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(1):66-69
In the title compound, C24H36N6O6·C2H6OS, the carbonyl groups are in an antiperiplanar conformation, with O=C—C=O torsion angles of 178.59 (15) and −172.08 (16)°. An intramolecular hydrogen‐bonding pattern is depicted by four N—H...O interactions, which form two adjacent S(5)S(5) motifs, and an N—H...N interaction, which forms an S(6) ring motif. Intermolecular N—H...O hydrogen bonding and C—H...O soft interactions allow the formation of a meso‐helix. The title compound is the first example of a helical 1,2‐phenylenedioxalamide. The oxalamide traps one molecule of dimethyl sulfoxide through N—H...O hydrogen bonding. C—H...O soft interactions give rise to the two‐dimensional structure. 相似文献
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The orientational ordering of three liquid crystals (trans,trans-4-n-alkyl-4'-cyanobicyclohexanes) has been investigated using 13C NMR. 2D proton-encoded local field spectroscopy was used to determine the 13C-1H dipolar coupling constants, from which the order parameters were calculated. Semi-empirical linear relations between the obtained order parameters and anisotropic 13C chemical shifts were established. It was found that the order parameters of the major axis of the cyclohexane rings are smaller than those of liquid crystals with phenyl rings, and the order parameters of the C-H bonds in the aliphatic chains also behave differently. 相似文献