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We made an anatomic study using a convenience sample of 20 patients, most of them referred to our institution for depicting internal auditory malformations that justify sensorineural deafness or for surgical planning of cochlear implants. All patients underwent a multislice temporal bone CT and oblique single slice reformation postprocessing in six proposed different planes corresponding to cochlear basal turn, apical basal turn, malleoincudal complex, stapes, and facial channel. Anatomic and pathologic characterization of some middle and inner ear structures, difficult to evaluate in standard axial and coronal planes, can be improved using this technique.  相似文献   
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Behavioural responses are linked to complex biochemical and physiologic changes and may act as sensitive indicators of the sublethal effects of pollutants. This article investigates changes in the locomotor activity rhythms of the amphipod Gammarus aequicauda exposed to cadmium (Cd) as a model to study the effect of pollutants on an ecologically important species. Under a 12:12 h light-to-dark cycle, G. aequicauda showed a strict nocturnal rhythm, with 90.2 ± 0.4% of their total daily activity occurring during the night. Under constant darkness, circadian rhythms persisted for 10 days, with a mean periodicity of 24.32 h, thus confirming endogenous control. Exposure to sublethal concentrations of Cd (0.16, 0.20, 0.24, and 0.28 mg l−1) did not change the nocturnal activity patterns of G. aequicauda, although their swimming activity during the night was significantly decreased by exposure to concentrations of 0.24 and 0.28 mg Cd l−1. In conclusion, locomotor activity bioassays using the amphipod G. aequicauda appeared to be a sensitive indicator of Cd contamination, and sensitivity and tolerance to Cd in short-term bioassays may depend on the time of the day tests are carried out. These results provide further support for the idea that behavioural end points in amphipods are useful indicators of pollutant exposure and that future studies should take circadian rhythms into consideration.  相似文献   
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We present a 29-year-old woman with a long history of attacks of migraine with and without visual aura. She was a heavy smoker (20 cigarettes/d) and was currently taking oral contraceptives. During a typical migraine attack with aura, she developed dysarthria, left brachial hemiparesis and hemihypoesthesia and brief and autolimited left clonic facial movements. Four hours after onset, vascular headache and focal sensorimotor neurological deficit were the only persisting symptoms and, on seventh day, she was completely recovered. Brain magnetic resonance imaging on day 20 after onset showed a subacute ischemic lesion in the right temporo-parietal cortex compatible with cortical laminar necrosis (CLN). Extensive neurological work-up done to rule out other known causes of cerebral infarct with CLN was unrevealing. Only ten of 3.808 consecutive stroke patients included in our stroke registry over a 19-year period fulfilled the strictly defined International Headache Society criteria for migrainous stroke. The present case is the unique one in our stroke registry that presents CLN related to migrainous cerebral infarction. Migrainous infarction can result in CLN.  相似文献   
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Smoldering multiple myeloma (SMM) is an asymptomatic plasma cell disorder characterized by the presence of one or both features of serum M-protein ≥?30 g/L and bone marrow plasma cell infiltration ≥?10 %. However, myeloma-related symptomatology is absent from this condition. The risk of progression to active MM is not uniform, and several markers are useful for identifying SMM patients at high risk of progression to active MM. These include the size of the M-protein and the infiltration in the bone marrow, the serum-free light-chain ratio, the presence of immunoparesis and percentage of plasma cell with aberrant phenotype by flow cytometry, or the presence of focal lesions in magnetic resonance imaging. Overall, the presence of these factors identifies patients who have a 50 % probability of progression at 2 years, and the forthcoming challenge will be to identify ultra-high-risk patients who have an 80 % risk of progression at 2 years. The current standard of care is not to treat until progression to symptomatic disease occurs. Several trials of melphalan, thalidomide and bisphosphonates have been conducted in the overall SMM patient population to examine the delay in time to progression (TTP) to symptomatic disease, but these have shown no significant benefit. However, a randomized trial that focused on high-risk SMM patients allocated to receive early treatment with lenalidomide plus dexamethasone versus observation did report a significant benefit with respect to TTP and overall survival. In summary, high-risk SMM patients should be targetted for early treatment, and more so efforts should be made to identify the ultra-high-risk subgroup within the high-risk SMM patient population which may be considered as early MM and thereby candidates for receiving therapy before they develop myeloma-related symptomatology.  相似文献   
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Juvenile-onset spondyloarthritis is a special group within the entities included in the concept of spondyloarthritis, and is characterized by a predominantly peripheral involvement (arthritis and enthesitis), and more frequent presentation as undifferentiated forms. However, like its adult-onset equivalent, it has the potential to develop structural damage and progress to juvenile ankylosing spondylitis, with consequent irreversible functional impairment. Many important advances have been made in the understanding of the genetics and pathophysiology of juvenile-onset spondyloarthritis, as well as in the diagnosis and treatment of this entity. These advances are summarized in this article.  相似文献   
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