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51.

Eruptive melanocytic nevi (EMN) is a phenomenon characterized by the sudden onset of nevi. Our objective was to compile all published reports of EMN to identify possible precipitating factors and to evaluate the clinical appearance and course. We conducted a systematic bibliographic search and selected 93 articles, representing 179 patients with EMN. The suspected causes were skin and other diseases (50%); immunosuppressive agents, chemotherapy or melanotan (41%); and miscellaneous, including idiopathic (9%). The clinical manifestations could largely be divided into two categories: EMN associated with skin diseases were frequently few in number (fewer than ten nevi), large, and localized to the site of previous skin disease, whereas those due to other causes presented most often with multiple small widespread nevi. In general, EMN seem to persist unchanged after their appearance, but development over several years or fading has also been reported. Overall, 16% of the cases had at least one histologically confirmed dysplastic nevus. Five cases of associated melanoma were reported. We conclude that the clinical appearance of EMN may differ according to the suggested triggering factor. Based on the clinical distinction, we propose a new subclassification of EMN: (1) widespread eruptive nevi (WEN), with numerous small nevi, triggered by, for example, drugs and internal diseases, and (2) Köbner-like eruptive nevi, often with big and few nevi, associated with skin diseases and most often localized at the site of previous skin disease/trauma. The nature of the data precluded assessment of risk of malignant transformation.

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Neurofibromatosis 1 is a multisystem disorder associated with substantial clinical variability. During childhood, few neurofibromas and café au lait spots may be the only manifest symptoms, making correct and timely diagnosis difficult. Herein we describe the clinical usefulness of ultrasound examination in identifying neurofibromas.  相似文献   
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Background: We evaluate the usefulness of screening for p53 and Ki-ras mutations in comparison with histological and flow cytometric findings. Methods: We analyzed 1486 biopsy samples from 769 locations of 83 patients with long-standing ulcerative colitis enrolled in a surveillance program by means of histology, flow cytometry and SSCP analysis. As a control we used 66 biopsy samples of 16 patients with irritable bowel disease. Results: With respect to all biopsy samples analyzed, DNA aneuploidy was found in 32.5% (27/83) of patients, dysplasia in 22.9% (15/83), p53 in 21.7% (18/83) and Ki-ras mutations in 18.1% (15/83) of patients. None of these markers was found in our control group. In 7 out of 10 patients who displayed dysplastic findings during endoscopic surveillance p53 and / or Ki-ras mutations were present in at least one colonoscopy. Statistically significant associations were observed between dysplasia and DNA aneuploidy ( P < 0.001), between dysplasia and p53 mutations ( P = 0.05) and between dysplasia and p53 and/or Ki-ras mutations ( P = 0.002). No significant associations were found between dysplasia and Ki-ras mutations alone. The results for the SSCP analysis showed a much broader variation than those for the flow cytometric analysis. Conclusions: These results show that screening for p53 and Ki-ras mutations can be a useful adjunct in surveillance of patients with longstanding ulcerative colitis.  相似文献   
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High‐definition OCT (HD‐OCT) is an innovative technique based on the principle of conventional OCT. Our objective was to test the resolution and image quality of HD‐OCT in comparison with reflectance confocal microscopy (RCM) of healthy skin. Firstly, images have been made of a ultra‐high‐resolution line‐pair phantome with both systems. Secondly, we investigated 21 healthy volunteers of different phototypes with HD‐OCT and RCM on volar forearm and compared the generated images. HD‐OCT displays also differences depending on the skin phototype and anatomical site. The 3‐μm lateral resolution of the HD‐OCT could be confirmed by the phantom analysis. The identification of cells in the epidermis can be made by both techniques. RCM offers the best lateral resolution, and HD‐OCT has the best penetration depth, providing images of individual cells deeper within the dermis. Eccrine ducts and hair shafts with pilosebaceous units can be observed depending on skin site. HD‐OCT provides morphological imaging with sufficient resolution and penetration depth to permit visualization of individual cells at up to 570 μm in depth offering the possibility of additional structural information complementary to that of RCM. HD‐OCT further has the possibility for rapid three‐dimensional imaging.  相似文献   
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During the last decades, atypical parkinsonian disorders such as multiple system atrophy, dementia with Lewy bodies, progressive supranuclear palsy, and corticobasal degeneration along with secondary parkinsonian disorders have been increasingly recognized as important causes of parkinsonism. Although treatment options are largely limited to date, remarkable progress has occurred through advances in the fields of molecular biology and diagnostic neuroimaging, resulting in intense preclinical drug discovery programs. Early‐investigation‐assisted clinical diagnosis has become more crucial than ever because disease‐modifying therapies will hopefully become available within this decade. © 2011 Movement Disorder Society  相似文献   
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