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Although magnetic resonance imaging (MRI) represents the most sensitive tool for the detection of white matter abnormalities in patients with multiple sclerosis (MS), the heterogeneity of MS placques severely hampers the elucidation of specific pathophysiological processes. In order to identify putative MRI markers for de- and remyelination, we employed the cuprizone mouse model which leads to a selective and reversible demyelination of the corpus callosum with little or no axonal damage. Apart from histopathology, animals were studied with high-resolution three-dimensional MRI in vivo using multiple contrasts. While individual MRI findings significantly correlated with electron microscopy, the differentiation of regions with normal, demyelinated or remyelinated white matter by one contrast alone was less specific than by histology or electron microscopy. However, an accurate MRI prediction of the in vivo myelin status was achieved by a discriminant function analysis using a combination of T1, T2 and magnetization transfer contrast. With a correct assignment of 95% of all animals examined, the procedure will allow for the survey of new therapeutic approaches aiming at improved remyelination.  相似文献   
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Free-roaming camels, especially those crossing national borders, pose a high risk for spreading Middle East respiratory syndrome coronavirus (MERS-CoV). To prevent outbreaks, active surveillance is necessary. We found that a high percentage of dromedaries in Tunisia are MERS-CoV seropositive (80.4%) or actively infected (19.8%), indicating extensive MERS-CoV circulation in Northern Africa.  相似文献   
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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Vor dem Hintergrund der derzeitigen COVID-19-Pandemie entstand die Idee zur Durchführung einer Studie, in der die...  相似文献   
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Meyer  Barbara  Graf  Lukas  Endermann  Susann 《Der Anaesthesist》2021,70(7):598-602
Die Anaesthesiologie - Die Immunthrombozytopenie (ITP) ist eine seltene, erworbene Thrombozytopenie mit einer Inzidenz von 2–4/100.000 Personen und Jahr. Sie wird durch eine Thrombozytenzahl...  相似文献   
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OBJECTIVE: To determine if there is an influence of body mass index (BMI) on the radiological progression in early and longer duration rheumatoid arthritis (RA). METHODS: Fifty-four patients with RA were observed in a progressive 2 year followup for radiological progression of joint damage. At the beginning of study, 27 (50%) patients had a duration of complaints less than 6 months, grouped as early RA. BMI at the beginning and end of the study were monitored, together with HLA-DRB1 alleles, initial joint erosions, duration of disease, age, sex, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP). Outcome was defined as radiographic damage according to yearly increase of Larsen score. RESULTS: Increased radiographic joint damage of patients was significantly correlated with lower BMI at the beginning of the study (r = 0.363, p < 0.05), the presence of initial joint erosions (r = 0.341, p < 0.01), ESR (r = 0.315, p < 0.05), and CRP at study entry (r = 0.427, p < 0.01). Patients with an increase of Larsen score > or = 5.8/year were found to have a lower weight at the beginning of their complaints (BMI 24.8 +/- 4.7 vs 27.8 +/- 3.8; p < 0.05) as well as after the time of observation (BMI 24.6 +/- 3.7 vs 27.6 +/- 4.9; p < 0.05). Stepwise logistic regression analysis revealed a BMI < 27 at the beginning of disease (beta = 2.04, p = 0.003, odds ratio = 7.69), the presence of HLA-DR4 shared epitope (beta = 1.76, p = 0.015, OR 5.82), and joint erosions at study entry (beta = 1.56, p = 0.044, OR 4.78) as significant predictors for rapid joint damage. CONCLUSION: Together with the presence of HLA-DR4 shared epitope and erosive disease at study entry, a low BMI at the beginning of RA was found in association with higher radiographic progression in RA. Accordingly, BMI could be of interest as a sensitive and inflammation-independent predictor for radiological outcome of RA.  相似文献   
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