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31.
Ioannis Tsitouridis PhD MD Charalampos Maskalidis MD Despoina Panagiotidou MD Eleni P Kariki MScHI MScHCM MD 《Journal of ultrasound in medicine》2014,33(10):1855-1864
We present the sonographic and magnetic resonance imaging findings of Leydig cell tumors in a series of patients, along with a brief review of the literature. We evaluated the sonographic features of 11 cases of Leydig cell tumors, including echogenicity, size, margins, and patterns of vascularity. The magnetic resonance imaging characteristics of 9 patients were also assessed, with special attention to the appearance of the tumors on T2-weighted imaging and postcontrast T1-weighted imaging. Seven tumors were hypoechoic, and 4 were almost isoechoic. Ten patients showed various patterns of hypervascularity in the tumors, combined in some cases with feeding vessels. One case presented with a single feeding vessel. The tumors showed homogeneous or heterogeneous low signal intensity on T2-weighted imaging and marked enhancement on postcontrast T1-weighted imaging. The small size of these tumors, the various patterns of vascularity on color and power Doppler sonography, and the marked enhancement on postcontrast T1-weighted imaging are considered valuable but generally nonspecific for identification of these tumors. 相似文献
32.
Theodoros N. Sergentanis Antonios G. Antoniadis Helen J. Gogas Constantine N. Antonopoulos Hans-Olov Adami Anders Ekbom Eleni Th. Petridou 《European journal of cancer (Oxford, England : 1990)》2013,49(3):642-657
Although obesity is an established risk factor for several cancer types, its possible role in the aetiology of malignant melanoma remains unclear. This meta-analysis aims to examine the association between obesity and melanoma risk, exploring any tentative gender-specific associations. After the identification of eligible studies, we estimated pooled effect estimates (odds ratios and relative risks), undertook a meta-regression analysis and analysed separately risk of malignant melanoma among males and females in relation to body mass index (BMI) and body surface area (BSA). Out of the 21 eligible articles, 11 used a case–control design encompassing 4460 cases/6342 controls; 10 used a cohort design whose total size comprised 7895 incident cases/6,368,671 subjects. Among males, the pooled effect estimate was 1.31 (95% confidence interval (CI): 1.18–1.45) for overweight and 1.31 (95% CI: 1.19–1.44) for obese. Meta-regression revealed no significant slope, most probably due to the underlying plateau in effect estimates. Among females, no significant association was documented; the pooled effect estimate for overweight and obese subjects was 0.98 (95% CI: 0.92–1.05) and 0.99 (95% CI: 0.83–1.18), respectively. Noticeably, there was evidence for confounding between sunlight exposure and obesity in females. All results were reproducible upon analyses on BSA. In conclusion, overweight and obesity are associated with increased risk of malignant melanoma among males. Meticulous assessment of sunlight exposure is needed especially in women, since self limited public sun exposure may be prevalent among overweight or obese females. Higher-order associations between BMI and melanoma risk should be addressed and examined by the future studies. 相似文献
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34.
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
35.
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
36.
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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38.
Vasileios Peppes George Rammos Efstathios Manios Eleni Koroboki Stylianos Rokas Nikolaos Zakopoulos 《Clinical Interventions in Aging》2008,3(4):699-710
Background
Our objective was to associate serum levels of myocardial enzymes and inflammatory biomarkers with severity of coronary artery disease (CAD).Patients and methods
123 patients participated in our study, including 65 cases of acute myocardial infarction (MI), 27 cases of newly diagnosed CAD – without MI – and 31 controls. In all subjects, myocardial serum enzyme levels (creatine phosphokinase, aspartate aminotransferase, lactate dehydrogenase) and inflammatory indices (C-reactive protein, fibrinogen, white blood cells, and erythrocyte sedimentation rate) were measured. Patients were all submitted to coronary angiography and CAD severity was evaluated by Gensini score.Results
Significant differences concerning enzyme serum levels and inflammatory indices were found to exist between the three study groups, being highest among patients with acute MI (p < 0.001). A significant association was demonstrated between Gensini score and serum enzyme levels as well as inflammatory biomarkers.Conclusions
Our findings suggest that serum levels of myocardial enzymes and inflammatory indices correlate with CAD severity in Greek patients. 相似文献39.
40.
Micheva I Thanopoulou E Michalopoulou S Kakagianni T Kouraklis-Symeonidis A Symeonidis A Zoumbos N 《British journal of haematology》2004,126(6):806-814
Myelodysplastic syndrome (MDS) is a stem cell disorder characterized by ineffective haematopoiesis and blood cytopenias. The present study investigated the potential of bone marrow CD34(+) progenitors in MDS patients to proliferate and differentiate into dendritic cells (DCs) in a cytokine-supplemented liquid culture system and analysed the status of blood DC subsets in these patients. CD34(+) progenitors had low potential to generate DCs in vitro, as the number of DCs obtained from one CD34(+) cell was significantly lower compared with controls (median value 0.2 vs. 4, P = 0.003). In patients, the survival and proliferation of CD34(+) cells in culture was not correlated to the degree of apoptosis. Phenotypically and functionally CD34(+)-derived DCs were similar in MDS patients and normal subjects. The percentage of both circulating DC subsets in patients was extremely diminished compared with controls (myeloid DC: 0.10 +/- 0.10% vs. 0.35 +/- 0.13%, P < 0.001; plasmacytoid DC: 0.11 +/- 0.10% vs. 0.37 +/- 0.14%, P < 0.001). In cases with the 5q deletion both CD34-derived DCs and blood DCs harboured the cytogenetic abnormality. Our results indicate that, in MDS, the production of DCs is affected by the neoplastic process resulting in ineffective 'dendritopoiesis' with low blood DC precursor numbers. This quantitative DC defect probably contributes to the poor immune response against infectious agents and to the escape of the malignant clone from immune recognition with disease progression towards acute leukaemia. 相似文献