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排序方式: 共有3228条查询结果,搜索用时 15 毫秒
41.
Maria Kostaki Argyro D. Manona Irene Stavraka Penelope Korkolopoulou Georgia Levidou Eleni‐Andriana Trigka Eleftheria Christofidou Grigorios Champsas Alexandros J. Stratigos Andreas Katsambas Othon Papadopoulos Christina Piperi Athanasios G. Papavassiliou 《Experimental dermatology》2014,23(5):332-338
Epigenetic mechanisms participate in melanoma development and progression. The effect of histone modifications and their catalysing enzymes over euchromatic promoter DNA methylation in melanoma remains unclear. This study investigated the potential association of p16INK4A promoter methylation with histone methyltransferase SETDB1 expression in Greek patients with sporadic melanoma and their correlation with clinicopathological characteristics. Promoter methylation was detected by methylation‐specific PCR in 100 peripheral blood samples and 58 melanoma tissues from the same patients. Cell proliferation (Ki‐67 index), p16INK4A and SETDB1 expression were evaluated by immunohistochemistry. High‐frequency promoter methylation (25.86%) was observed in tissue samples and correlated with increased cell proliferation (P = 0.0514). p16INK4A promoter methylation was higher in vertical growth‐phase (60%) melanomas than in radial (40%, P = 0.063) and those displaying epidermal involvement (P = 0.046). Importantly, p16INK4A methylation correlated with increased melanoma thickness according to Breslow index (P = 0.0495) and marginally with increased Clark level (I/II vs III/IV/V, P = 0.070). Low (1–30%) p16INK4A expression was detected at the majority (19 of 54) of melanoma cases (35.19%), being marginally correlated with tumor lymphocytic infiltration (P = 0.078). SETDB1 nuclear immunoreactivity was observed in 47 of 57 (82.46%) cases, whereas 27 of 57 (47.37%) showed cytoplasmic immunoexpression. Cytoplasmic SETDB1 expression correlated with higher frequency of p16INK4A methylation and p16INK4A expression (P = 0.033, P = 0.011, respectively). Increased nuclear SETDB1 levels were associated with higher mitotic count (0–5/mm2 vs >5/mm2, P = 0.0869), advanced Clark level (III‐V, P = 0.0380), epidermal involvement (P = 0.0331) and the non‐chronic sun exposure‐associated melanoma type (P = 0.0664). Our data demonstrate for the first time the association of histone methyltransferase SETDB1 with frequent methylation of the euchromatic p16INK4A promoter and several prognostic parameters in melanomas. 相似文献
42.
Kostas Fasoulas Athanasios Beltsis Taxiarchis Katsinelos Eleni Dimou Mary Arvaniti Anna Charsoula Victor Gourvas Stefanos Atmatzidis Grigoris Chatzimavroudis Panagiotis Katsinelos 《Saudi Journal Of Gastroenterology》2012,18(2):146-148
Mesenteric panniculitis (MP) is a rare inflammatory and fibrotic disease of the mesentery of unknown etiology. It has various clinical and radiological manifestations, posing a diagnostic challenge for clinicians. Its diagnosis is indicated via radiologic imaging and is usually confirmed via peritoneal biopsies. We describe a case of a patient with histopathologically proven MP, in which steroid dependence was successfully managed with colchicine. 相似文献
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Evaluation of T‐lymphocyte subpopulations in actinic keratosis,in situ and invasive squamous cell carcinoma of the skin
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45.
Eleni Vradi Werner Brannath Thomas Jaki Richardus Vonk 《Journal of biopharmaceutical statistics》2018,28(4):735-749
The growing role of targeted medicine has led to an increased focus on the development of actionable biomarkers. Current penalized selection methods that are used to identify biomarker panels for classification in high-dimensional data, however, often result in highly complex panels that need careful pruning for practical use. In the framework of regularization methods, a penalty that is a weighted sum of the L1 and L0 norm has been proposed to account for the complexity of the resulting model. In practice, the limitation of this penalty is that the objective function is non-convex, non-smooth, the optimization is computationally intensive and the application to high-dimensional settings is challenging. In this paper, we propose a stepwise forward variable selection method which combines the L0 with L1 or L2 norms. The penalized likelihood criterion that is used in the stepwise selection procedure results in more parsimonious models, keeping only the most relevant features. Simulation results and a real application show that our approach exhibits a comparable performance with common selection methods with respect to the prediction performance while minimizing the number of variables in the selected model resulting in a more parsimonious model as desired. 相似文献
46.
Stamatia Theodoridou Aikaterini Teli Eleni Yfanti Timoleon-Achilleas Vyzantiadis Theodoros Theodoridis Marina Economou 《Hemoglobin》2018,42(2):129-131
Hb Adana (HBA2: c.179G>A) is found worldwide but is extremely rare and carriers are asymptomatic, with red cell indices similar to α+-thalassemia (α+-thal) carriers. First line screening tests are unable to detect the unstable hemoglobin (Hb). Coinheritance with the α-thal (–α3.7) deletion is herein presented and the challenges involving genetic counseling of couples carrying the mutations are discussed. 相似文献
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Claudia Eleni Goffredo Grifoni Alessandra Di Egidio Roberta Meoli Claudio De Liberato 《Parasitology research》2014,113(3):1247-1250
In Europe, the red fox (Vulpes vulpes) is considered the reservoir of Angiostrongylus vasorum, nematode residing in the pulmonary arteries and right heart of dogs and many species of wild carnivores. Italy is considered one of the European countries where this nematode is actually spreading. Between May 2007 and November 2013, 62 foxes found dead in Central Italy were necropsied. Right heart and pulmonary arteries were opened and checked for the presence of adult parasites. Impression smears from sectioned lungs were examined for the presence of first-stage larvae, and samples of lungs were processed for histological examination. In order to detect eventual disseminated infections, samples of heart, pulmonary lymph nodes, liver, kidneys, and brain of foxes positive for A. vasorum at necropsy or lungs histological examination were processed for histological examination. An overall prevalence of 43.5 % was recorded. Light, mild, and severe lung lesions were detected in 33.3, 22.2, and 25.9 % of infected animals, respectively. Severe lesions were more frequent in animals younger than 12 months. In five infected foxes (18.5 %), no gross lesions were observed, while for three animals, angiostrongylosis was considered the cause of death. A case of disseminated angiostrongylosis was detected and another one was suspected. This is the firs report of disseminated angiostrongylosis in the fox. 相似文献
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