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L. Di Angelo P. Di Stefano A. E. Morabito 《International Journal on Interactive Design and Manufacturing》2018,12(3):801-809
A new method for secondary features segmentation, performed on high-density tessellated geometric models, is proposed. Four types of secondary features are considered: fillets, rounds and grooves. Sharp edges are also recognised. The method is based on an algorithm that analyses the principal curvatures. The nodes, potentially attributable to a fillet of given geometry, are those with a certain value for the maximum principal curvature. Since the deterministic application of this simple working principle shows several problems, due to the uncertainties in the curvature estimation, a fuzzy approach is proposed. In order to segment the nodes of a tessellated model belonging to secondary features of a given radius, an appropriate set of membership functions is defined and evaluated based on some parameters, which affect the quality of the curvature estimation. A region-growing algorithm connects the nodes pertaining to a same secondary feature so that, for a given radius, one or more secondary features may be recognized. The method is applied and verified in some test cases. 相似文献
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Patrizia Rovere-Querini Maria Teresa Castiglioni Maria Grazia Sabbadini Angelo A. Manfredi 《Autoimmunity》2013,46(4):290-294
Apoptosis normally occurs in the human placenta. As a consequence, cell blebs, post-apoptotic debris (also referred to as syncytial knots) and membrane microparticles are released into the blood of pregnant women. These events become prominent during the best-characterized pregnancy complication, pre-eclampsia. An excessive or deregulated cell death, which results in the generation of an overwhelming burden of apoptotic material, alarms the immune system. This plays a role in the pathogenesis of systemic connective tissue diseases and possibly of small vessels vasculitis. Infiltration of leukocytes and activation of endothelial cells and platelets are hallmarks of normal pregnancy, indicating that physiologic pregnancy is a condition characterized by an activation of the innate immune system. Conversely, a failure in the physiologic termination of inflammatory events is probably a requirement for pre-eclampsia to develop. Here, we discuss recent findings suggesting a link between deregulated disposal of placental debris, the generation of endogenous pro-inflammatory signals (alarmins) and the widespread vascular inflammation that characterizes on one hand pre-eclampsia and on the other systemic autoimmune diseases. 相似文献
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A complex ventricular septal defect following transcatheter aortic valve implantation evaluated by 3D transthoracic echocardiography
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Giovanni Barbati MD Roberto Zeppellini MD Giovanna Erente MD Angelo B. Ramondo MD 《Echocardiography (Mount Kisco, N.Y.)》2018,35(1):126-128
Transcatheter aortic valve implantation (TAVI) has revolutionized the treatment of elderly patients with symptomatic severe aortic valve stenosis. Among the possible TAVI complications, a rare one is the annular/left ventricular outflow tract rupture. We report a rare case of a late complex ventricular septal defect (VSD) following TAVI with a balloon‐expandable prosthesis, conservatively managed. Our case demonstrates the role of 3D transthoracic echocardiography (3DTTE) in the accurate diagnosis of this TAVI complication and suggests that, in some cases, it can be used as an alternative to other diagnostic tools, such as transesophageal echocardiography, cardiac catheterization, and computed tomography. 相似文献
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Method to improve minute ventilation (MV) during spontaneous breathing (SB) in stable severe chronic obstructive pulmonary disease (COPD) have a great clinical relevant in long term outcome. In this scenario, recommendations of early use of high-Intensity non-invasive Positive pressure Ventilation (HI-NPPV) or intelligent Volume Assured Pressure (iVAP) Support in Hypercapnic COPD have been proposed by safe therapeutics options. We analyze in this letter, Ekkernkamp et al. study that described the effect of HI-NPPV compared with SB on MV in patients receiving long-term treatment. We consider that interpretation of relationships between ABG, functional parameters, and respiratory mechanics reported need clarifications. Further prospective large clinical trials identifying the best mode of ventilation according to the characteristics in severe stable COPD are necessary to balance an effective approach and response on clinical symptoms and long-term effects. 相似文献
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Katia Falasca Jacopo Vecchiet Claudio Ucciferri Marta Di Nicola Chiara D’Angelo Marcella Reale 《Nutrients》2015,7(10):8335-8347
Inflammation persists in patients infected with HIV. Reduction of inflammatory cytokines and microbial translocation might be one way that this could be managed. Purpose: The anti-inflammatory properties of certain probiotic strains prompted us to investigate whether a probiotic could reduce the inflammatory index of HIV-infected patients. Methods: The study involved 30 HIV+ males on antiretroviral therapy, who were given one bottle of fermented milk Yakult Light® containing Lactobacillus casei Shirota (LcS) twice a day for four weeks. Results: The probiotic LcS was associated with an increase of T lymphocytes and a significant increase of CD56+ cells (p = 0.04). There was also a significant decrease of mRNA levels of TGFβ, IL-10 and IL-12 (p < 0.001) and IL-1β expression (p < 0.001) and an increase of serum IL-23 (p = 0.03). In addition, decreased inflammation and cardiovascular risk were observed, as shown by a reduction of cystatin C (p < 0.001). Conclusions: These data provide preliminary evidence that probiotic supplementation may modulate certain immunological parameters and some of the cytokines that were analyzed. Thus, we propose that LcS may be an inexpensive and practical strategy to support the immune function of HIV+ patients. 相似文献
128.
The worldwide incidence of hepatocellular carcinoma (HCC) continues to rise and liver transplantation (LT) represents an established curative treatment for early stage disease. As a result of organ shortage, guidelines have restricted transplantation to HCC patients with an expected 5-year post transplantation survival greater than 70 %. The Milan criteria (MC) remain a reliable and noninvasive instrument for selecting patients with 5-year survival meeting this criteria. Since the adoption of the MC by United Network for Organ Sharing (UNOS), attempts have been made to expand MC to account for the projected increase in the incidence of HCC over the next 20 years. An area of active debate focuses on identifying a subgroup of patients outside of MC with similar or better outcomes through either new expanded criteria or identifying other prognostic factors to enhance MC. 相似文献
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