In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
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Question: Context: Magnetic Resonance Imaging (MRI) allows a detailed "in vivo" macroscopic study of the human brain; previously, it has been demonstrated that Fluid Attenuated Inversion Recovery (FLAIR) sequence shows higher signal intensity of cortices belonging to limbic structures.', 'To measure and compare signal intensities (SI) of cytoarchitectonically different cortical regions.', 'In 22 adult subjects, without psychiatric or neurological diseases, FLAIR sequence was performed in coronal slices, perpendicular to the main hippocampal axis. Signal intensity was measured, with a region-of-interest (ROI) function, in 12 different cortical regions. We compared these values and grouped the cortices into five groups: (1) limbic cortices, (2) paralimbic agranular cortices, (3) paralimbic granular cortices, (4) parietal-type neopallium, (5) frontal-type neopallium. A t-test for comparison of paired samples was performed, considering p</=0.05 as statistically significant.', 'We found statistically significant differences amongst the different groups, with the exception of groups 1 and 2, which did not show differences between them. No statistically significant differences were found among cortices belonging to the same group.\Question: Does magnetic resonance imaging identify cytoarchitectonic subtypes of the normal human cerebral cortex?

Answer: Structural characteristics of the cerebral cortex cause changes in its signal intensity. Magnetic resonance imaging (FLAIR sequence) allows discrimination of different cytoarchitectonic areas of the human cerebral cortex.


Question: Context: Transcranial direct current stimulation (tDCS) of the primary motor cortex has been shown to modulate pain and trigeminal nociceptive processing.', 'Ten patients with classical trigeminal neuralgia (TN) were stimulated daily for 20\xa0minutes over two weeks using anodal (1\xa0mA) or sham tDCS over the primary motor cortex (M1) in a randomized double-blind cross-over design. Primary outcome variable was pain intensity on a verbal rating scale (VRS 0-10). VRS and attack frequency were assessed for one month before, during and after tDCS. The impact on trigeminal pain processing was assessed with pain-related evoked potentials (PREP) and the nociceptive blink reflex (nBR) following electrical stimulation on both sides of the forehead before and after tDCS.', 'Anodal tDCS reduced pain intensity significantly after two weeks of treatment. The attack frequency reduction was not significant. PREP showed an increased N2 latency and decreased peak-to-peak amplitude after anodal tDCS. No severe adverse events were reported.\Question: Does patient-conducted anodal transcranial direct current stimulation of the motor cortex alleviate pain in trigeminal neuralgia?

Answer: Anodal tDCS over two weeks ameliorates intensity of pain in TN. It may become a valuable treatment option for patients unresponsive to conventional treatment.


Question: Context: Severe mitral regurgitation (MR) reduces left atrial thrombus formation in patients with mitral stenosis (MS) and atrial fibrillation (AF). Plasma D-dimer levels represent a biochemical marker for fibrinolytic activity in prothrombotic states. The prothrombotic burden in patients with mitral valve disease and/or AF was assessed using plasma D-dimer levels.', 'The study population included 89 patients with mitral valve disease, 21 with AF but normal valves, and 15 healthy controls. The mitral valve group was subdivided into patients with MS (n = 27), severe MR (n = 26), and MS with concomitant with severe MR (MS/MR; n = 36). These subgroups were further subdivided according to the atrial rhythm (sinus rhythm (SR)+AF).', 'The mean left atrial size was increased in all groups with cardiac disease. D-dimer levels were highest in the MS+AF subgroup (527 +/- 134 microg/l). Patients with MS+AF, MS+SR, and nonvalvular AF had significantly higher D-dimer levels than controls (p < 0.01, by ANOVA). Patients with MR had normal levels of D-dimer. The atrial rhythm did not influence D-dimer levels in the MS/MR subgroup, or in the pure MR subgroup (p = NS).\Question: Does mitral regurgitation reduce systemic coagulation activity in patients with rheumatic heart disease?

Answer:
Plasma D-dimer levels correlated with the embolic risk in mitral valve disease and non-valvular AF. The highest levels were found in patients with MS+AF and non-valvular AF. Severe MR decreased the D-dimer levels in MS and/or AF to control levels.