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991.
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Manuel Valdebran Justin Bandino Amira Elbendary Abdallah Gad Krishna C. Arudra Sébastien de Feraudy Dirk M. Elston 《Journal of cutaneous pathology》2018,45(3):204-207
Background
Interpretation of Clark's nevi has generated debate over the years; although criteria have been proposed for grading morphological features of melanocytes, there is still confusion and variability in the assessment of these lesions.Methods
This is a retrospective observational study conducted on 100 Clark's nevi and 84 melanomas. A single expert dermatopathologist evaluated all blinded and randomized photomicrographs of both the Clark's nevi and melanomas for the presence of 14 cytologic features. Subsequently, a multivariate model was used to obtain sensitivity and specificity.Results
Clark's nevi showed a significantly higher frequency of absent‐or‐inconspicuous nucleoli over melanoma, whereas mitotic figures, pleomorphism, notching, multiple nucleoli, peppered moth nuclear pattern, flattened adjacent nuclei, prominent nucleoli and vesicular nucleus with rounded nucleoli were found significantly higher in frequency in melanomas.Conclusion
Our data suggest that nuclear alterations are of value in the differentiation of atypical nevi from melanoma. 相似文献995.
Dwarikanath Mahapatra Peter Schueffler Jeroen A. W. Tielbeek Joachim M. Buhmann Franciscus M. Vos 《Journal of digital imaging》2013,26(5):920-931
Increasing incidence of Crohn’s disease (CD) in the Western world has made its accurate diagnosis an important medical challenge. The current reference standard for diagnosis, colonoscopy, is time-consuming and invasive while magnetic resonance imaging (MRI) has emerged as the preferred noninvasive procedure over colonoscopy. Current MRI approaches assess rate of contrast enhancement and bowel wall thickness, and rely on extensive manual segmentation for accurate analysis. We propose a supervised learning method for the identification and localization of regions in abdominal magnetic resonance images that have been affected by CD. Low-level features like intensity and texture are used with shape asymmetry information to distinguish between diseased and normal regions. Particular emphasis is laid on a novel entropy-based shape asymmetry method and higher-order statistics like skewness and kurtosis. Multi-scale feature extraction renders the method robust. Experiments on real patient data show that our features achieve a high level of accuracy and perform better than two competing methods. 相似文献
996.
《Expert Review of Clinical Immunology》2013,9(4):621-631
The care of inflammatory bowel disease has changed considerably with the introduction of a number of immunosuppressants including anti-metabolite and anti-TNF therapies. While efficacious, these medications also carry important risks, notably the potential risk of lymphoma. This risk is one of the most worrisome for both patients and physicians. Our current knowledge is still evolving; however, our understanding of what risks these drugs carry, both individually and synergistically, is critical in allowing informed decision making. In this article, we will describe the known lymphoma risks of commonly used immunosuppressant medications in inflammatory bowel disease, with an emphasis on non-Hodgkin’s lymphoma and hepatosplenic T-cell lymphoma. 相似文献
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BackgroundThe association between cerebrovascular atherosclerosis and Alzheimer’s disease (AD) has been examined in many cross-sectional studies; however, there are few data regarding the role of cerebrovascular atherosclerosis on the longitudinal course of cognitive decline in AD. The aim of this study was to examine the progression of cognitive function in AD patients with cerebrovascular atherosclerosis compared to those without atherosclerosis over a two-year period.MethodsForty-seven AD patients with cerebrovascular atherosclerosis and 81 AD patients without atherosclerosis were assessed for cognitive function at the time of diagnosis and again at follow-up after two years. The cognitive functions were evaluated by neuropsychological tests including mini-mental state examination (MMSE) and clinical dementia scale (CDR).ResultsRepeated-measures multivariate analyses showed that there was a significant group-by-time interactions for the temporal changes of the MMSE and CDR between the two groups. The group-by-time interactions remained significant when the atherosclerotic patients were sub-classified into either an extracranial stenosis (EC) group or an intracranial stenosis(IC) group. Comparing either the EC or IC group with the non-atherosclerosis group, there were no main effects by time or group alone, but there were significant group-by-time interactions for the MMSE and CDR.ConclusionsCognitive function worsened more in terms of progressive impairment in AD patients with cerebrovascular atherosclerosis compared to AD patients without cerebrovascular atherosclerosis, regardless of whether the atherosclerosis was extracranial or intracranial. 相似文献
999.
Hiroyuki Onozu Shuichi Yamamoto Kenji Takou Seiji Hasyasaka 《Neuro-ophthalmology (Aeolus Press)》2013,37(3):145-150
A 16-year-old girl hospitalized with a sudden onset of blepharoptosis and diplopia revealed a combined paresis of the elevator palpebrae, the superior rectus, and the medial rectus muscles of the left eye as quantitatively demonstrated by the Hess chart and levator action test. A small midbrain lesion confined to the left cerebral peduncle and tegmentum, presumably by an ischemic or demyelinative process, was identified on magnetic resonance imaging. Despite uncertainty in its pathology, the incomplete oculomotor palsy of this case is certainly a consequence of oculomotor fascicular involvement in the intra-axial nerve root which initially fans out and then converges into the peripheral compact bundle. We speculate on the revised version of the oculomotor fascicular arrangements by which the neurophthalmologic features of the current case are better explained. 相似文献
1000.
《Journal of Children and Media》2013,7(1):114-132
This article explores internet-related parent–child relationships across twenty-five European countries. Parent–child dyads are analysed in terms of parental mediation, digital competence, and communicative proximity, in order to answer the following research questions: Which types of parent–child relationship with respect to internet use can be found? How do they coincide with developmental, social, and cultural patterns? And how are they distributed across European Union countries? Using data from the EU Kids Online survey, four types of parent–child relationship were identified. The types are shaped by several factors on the level of child, family, and country, with the child's age and internet use being the most important predictors. Based on the prevalence of these family types, six country clusters were identified, which represent technical, social, and cultural contexts shaping the type of internet-related parent–child relationship. 相似文献