Search results for "pret"
showing 10 items of 2250 documents
Basal opioid receptor binding is associated with differences in sensory perception in healthy human subjects: a [18F]diprenorphine PET study.
2009
The endogenous opioid system is involved in many body functions including pain processing and analgesia. To determine the role of basal opioid receptor availability in the brain in pain perception, twenty-three healthy subjects underwent positron emission tomography (PET) utilizing the subtype-nonselective opioid antagonist [(18)F]diprenorphine, quantitative sensory testing (QST) and the cold pressor test. Binding potentials (BPs) were calculated using a non-invasive reference tissue model and statistical parametric mapping was applied for t-statistical analysis on a voxelwise basis. We found that cold pain-sensitive subjects present a significantly lower BP in regions including the bilater…
High-b-Value Diffusion-weighted MR Imaging of Benign Hepatocellular Lesions: Quantitative and Qualitative Analysis
2012
PURPOSE:To analyze the signal intensity (SI) of benign hepatocellular lesions in high-b-value diffusion-weighted (DW) magnetic resonance (MR) images and to compare the apparent diffusion coefficient (ADC) values of focal nodular hyperplasias (FNHs) with those of hepatocellular adenomas (HCAs). MATERIALS AND METHODS: This retrospective study was approved by institutional review board, with waiver of informed consent. Inclusion criteria were consecutive patients with diagnosed FNH or HCA who underwent MR imaging with a DW sequence of the liver at three b values, 0, 150, and 600 sec/mm2. The final study population included 67 patients (seven men, 60 women) with 90 hepatocellular lesions (54 FN…
MRI pattern recognition in multiple sclerosis normal-appearing brain areas
2011
ObjectiveHere, we use pattern-classification to investigate diagnostic information for multiple sclerosis (MS; relapsing-remitting type) in lesioned areas, areas of normal-appearing grey matter (NAGM), and normal-appearing white matter (NAWM) as measured by standard MR techniques.MethodsA lesion mapping was carried out by an experienced neurologist for Turbo Inversion Recovery Magnitude (TIRM) images of individual subjects. Combining this mapping with templates from a neuroanatomic atlas, the TIRM images were segmented into three areas of homogenous tissue types (Lesions, NAGM, and NAWM) after spatial standardization. For each area, a linear Support Vector Machine algorithm was used in mult…
Error in Intensive Care
2014
Objective To identify the psychological repercussions of an error on professionals in intensive care and to understand their evolution. To identify the psychological defense mechanisms used by professionals to cope with error. Design Qualitative study with clinical interviews. We transcribed recordings and analysed the data using an interpretative phenomenological analysis. Setting Two ICUs in the teaching hospitals of Besancon and Dijon (France). Subjects Fourteen professionals in intensive care (20 physicians and 20 nurses). Interventions None. Measurements and main results We conducted 40 individual semistructured interviews. The participants were invited to speak about the experience of…
Linguistic Bias Modulates Interpretation of Speech via Neural Delta-Band Oscillations.
2017
Language comprehension requires that single words be grouped into syntactic phrases, as words in sentences are too many to memorize individually. In speech, acoustic and syntactic grouping patterns mostly align. However, when ambiguous sentences allow for alternative grouping patterns, comprehenders may form phrases that contradict speech prosody. While delta-band oscillations are known to track prosody, we hypothesized that linguistic grouping bias can modulate the interpretational impact of speech prosody in ambiguous situations, which should surface in delta-band oscillations when grouping patterns chosen by comprehenders differ from those indicated by prosody. In our auditory electroenc…
Perceptual Correlate of Nociceptive Long-Term Potentiation (LTP) in Humans Shares the Time Course of Early-LTP
2006
As in neocortex and hippocampus, neurons in the dorsal horn of the spinal cord develop long-term potentiation of synaptic efficacy (LTP) on high-frequency stimulation (HFS) of their afferent input, although how long LTP lasts in this nociceptive relay nucleus has not yet been addressed. Here we studied neurogenic hyperalgesia, a perceptual correlate of nociceptive LTP, in 13 healthy subjects, after HFS (5 × 1 s at 100 Hz) of superficial cutaneous afferents. HFS led to a mean upward shift of the stimulus–response function for pinprick-evoked pain (punctate mechanical hyperalgesia) in all subjects by a factor of 2.5 ( P < 0.001) that lasted undiminished for the initial 1-h observation per…
Muscle-tendon interaction and elastic energy usage in human walking
2005
The present study was designed to explore how the interaction between the fascicles and tendinous tissues is involved in storage and utilization of elastic energy during human walking. Eight male subjects walked with a natural cadence (1.4 ± 0.1 m/s) on a 10-m-long force plate system. In vivo techniques were employed to record the Achilles tendon force and to scan real-time fascicle lengths for two muscles (medial gastrocnemius and soleus). The results showed that tendinous tissues of both medial gastrocnemius and soleus muscles lengthened slowly throughout the single-stance phase and then recoiled rapidly close to the end of the ground contact. However, the fascicle length changes demonstr…
Placental metal concentrations and birth outcomes: The Environment and Childhood (INMA) project
2019
To examine the association of placental levels of arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), manganese (Mn), and chromium (Cr) with birth outcomes (birth weight, length, and head circumference, low birth weight [LBW], gestational age, preterm delivery, and small for gestational age [SGA]) in mother-child pairs from the Environment and Childhood (INMA) Project in Spain.Metal concentrations were measured in placenta tissue samples randomly selected from five INMA cohorts. Data on birth outcomes were obtained from medical records. Associations were assessed in a sub-sample of 327 mother-infant pairs by regression models adjusted for confounding factors and for all metals simultaneous…
Virtual Unenhanced Images at Dual-Energy CT: Influence on Renal Lesion Characterization
2019
Background Dual-energy (DE) CT allows reconstruction of virtual noncontrast (VNC) images from a single-phase contrast agent-enhanced examination, potentially reducing the need for multiphasic CT to characterize renal lesions. However, data regarding diagnostic performance of VNC images for the characterization of renal lesions are limited. Purpose To determine whether renal mass CT performed by using VNC images allows for reliable identification of renal lesions and differentiation of contrast-enhanced from unenhanced lesions, compared with unenhanced images. Materials and Methods This is a retrospective study of 293 patients (105 women [mean age, 65 years; age range, 18-91 years] and 188 m…
Functional imaging of sympathetic activation during mental stress
2010
Activation of the sympathetic nervous system (SNS) is essential in adapting to environmental stressors and in maintaining homeostasis. This reaction can also turn into maladaptation, associated with a wide spectrum of stress-related diseases. Up to now, the cortical mechanisms of sympathetic activation in acute mental stress have not been sufficiently characterized. We therefore investigated cerebral activation applying functional magnetic resonance imaging (fMRI) during performance of a mental stress task with graded levels of difficulty, i.e. four versions of a Stroop task (Colour Word Interference Test, CWT) in healthy subjects. To analyze stress-associated sympathetic activation, skin c…