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51.
Elisa Veronese Roberto Stramare Andrea Campion Bernd Raffeiner Valeria Beltrame Elena Scagliori Alessandro Coran Luca Ciprian Ugo Fiocco Enrico Grisan 《Medical engineering & physics》2013,35(2):188-194
Rheumatoid arthritis (RA) is a chronic multisystemic autoimmune disease, with an unclear etiopathogenesis. Its early diagnosis and activity assessment are essential to adjust the proper therapy. Among the different imaging techniques, ultrasonography (US) allows direct visualization of early inflammatory joint changes as synovitis, being also rapidly performed and easily accepted by patients. We propose an algorithm to semi-automatically detect synovial boundaries on US images, requiring minimal user interaction. In order to identify the synovia-bone and the synovia-soft tissues interfaces, and to tackle the morphological variability of diseased joints, a cascade of two different active contours is developed, whose composition corresponds to the whole synovial boundary.The algorithm was tested on US images acquired from proximal interphalangeal (PIP) and metacarpophalangeal (MCP) finger joints of 34 subjects. The results have been compared with a consensus manual segmentation. We obtained an overall mean sensitivity of 85 ± 13%, and a mean Dice's similarity index of 80 ± 8%, with a mean Hausdorff distance from the manual segmentation of 28 ± 10 pixels (approximately 1.4 ± 0.5 mm), that are a better performance than those obtained by the raters with respect to the consensus. 相似文献
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Mortality After Admission to Stroke Unit for Intracerebral Hemorrhage: Effect of Age 80 and Older and Multimorbidity 下载免费PDF全文
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Thalassaemia major and infectious risk: High Mobility Group Box‐1 represents a novel diagnostic and prognostic biomarker 下载免费PDF全文
Valeria Chirico Antonio Lacquaniti Basilia Piraino Maricia Cutrupi Caterina Cuppari Luisa Grasso Luciana Rigoli Antonio David Teresa Arrigo Carmelo Salpietro 《British journal of haematology》2015,171(1):130-136
High mobility group box ‐1 (HMGB1) represents a common causal agent for various types of diseases, including infective pathologies. This study aimed to investigate the role of HMGB1 in β‐thalassemia major (TM) by evaluating its diagnostic and prognostic role. Fifty‐one TM patients and 30 healthy subjects (HS) were enrolled. Receiver operating characteristics (ROC) analysis was employed to calculate the area under the curve (AUC) for HMGB1 to determine the best cut‐off values capable of identifying infectious episodes. Adjusted risk estimates for infective events were calculated using univariate followed by multivariate Cox proportional hazard regression analysis. Serum HMGB1 levels were higher in TM patients than in HS (14·6 ± 8·7 vs. 2·08 ± 0·9 ng/ml, P < 0·0001). Patients who underwent splenectomy were characterized by lower levels of HMGB1, when compared with patients with an intact spleen (10·2 ± 8 vs. 19·1 ± 7 ng/ml, P = 0·004). ROC analyses revealed an AUC for serum HMGB1 of 0·801, with a sensitivity and specificity of 92·3% and 68·2% to detect an infectious episode. Low HMGB1 levels predicted high risk of infective events (HR: 0·81; P = 0·006). HMGB1 represents a prognostic marker for TM patients and a predictive factor for infectious events. 相似文献
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Raffaella Santi Alessandro Franchi Valeria Saladino Massimo Trovati Giovanna Cenacchi Massimo Squadrelli-Saraceno Gabriella Nesi 《Head and neck pathology》2015,9(2):300-304
Paragangliomas (PGs) of the head and neck region are typically benign, slow-growing neuroendocrine tumours. At times, they may exhibit unusual histological features, such as prominent stromal sclerosis (sclerosing PG), which may raise concerns of malignancy. We describe a case of sclerosing PG of the carotid body, emphasizing the value of immunohistochemical stains for differential diagnosis. A 43-year-old woman presented with a painless lump on the neck. A magnetic resonance imaging scan demonstrated a hypervascular lesion of the carotid body, which was surgically excised. Grossly, the lesion measured 1.8 cm at maximum diameter. On microscopic examination, irregular nests and tiny bundles of neoplastic cells were found between thick bands of fibrous tissue. Focal nuclear cytomegaly and marked pleomorphism were noted. Neoplastic cells proved to be immunoreactive for chromogranin, synaptophysin and neuron specific enolase, but negative for cytokeratins, smooth muscle actin and CD34. Ultrastructurally, numerous mitochondria, rough endoplasmic reticulum structures and endocrine granules were seen in the cytoplasm of the tumour cells. On consideration of the above-mentioned clinico-pathological and ultrastructural findings a diagnosis of sclerosing PG was established. Sclerosing PG is a rare entity which may mimic a malignant neoplasm. The recognition of this unusual morphological variant of PG, together with appropriate immunostains, leads to the correct diagnosis. 相似文献
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Zuccotti M Garagna S Merico V Monti M Alberto Redi C 《Molecular and cellular endocrinology》2005,234(1-2):11-17
Although the female gamete is blocked at the dictyate stage of the first meiotic prophase during the whole folliculogenesis, many important epigenetic changes occur to organise the genome to attend early embryonic development. In this paper, we will describe the results of a number of studies aimed to improve our understanding of the nuclear organization of the mouse oocyte during folliculogenesis. Using silver methods that stain NOR, centromeres and heterochromatin, as well as, the use of specific antibodies for the demonstration of centromeres, we have described the changes to the chromatin organisation and to the spatial localisation of chromocenters and centromeres during oocyte growth; these changes have been correlated to the developmental competence of the resulting antral and metaphase II (MII) oocyte. 相似文献
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