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排序方式: 共有3392条查询结果,搜索用时 15 毫秒
31.
Stéphane Terry Ihsan Y. El-Sayed Damien Destouches Pascale Maillé Nathalie Nicolaiew Guillaume Ploussard Fannie Semprez Cynthia Pimpie Himisha Beltran Arturo Londono-Vallejo Yves Allory Alexandre de la Taille David S. Salomon Francis Vacherot 《Oncotarget》2015,6(14):11994-12008
Members of the EGF-CFC (Cripto, FRL-1, Cryptic) protein family are increasingly recognized as key mediators of cell movement and cell differentiation during vertebrate embryogenesis. The founding member of this protein family, CRIPTO, is overexpressed in various human carcinomas. Yet, the biological role of CRIPTO in this setting remains unclear. Here, we find CRIPTO expression as especially high in a subgroup of primary prostate carcinomas with poorer outcome, wherein resides cancer cell clones with mesenchymal traits. Experimental studies in PCa models showed that one notable function of CRIPTO expression in prostate carcinoma cells may be to augment PI3K/AKT and FGFR1 signaling, which promotes epithelial-mesenchymal transition and sustains a mesenchymal state. In the observed signaling events, FGFR1 appears to function parallel to AKT, and the two pathways act cooperatively to enhance migratory, invasive and transformation properties specifically in the CRIPTO overexpressing cells. Collectively, these findings suggest a novel molecular network, involving CRIPTO, AKT, and FGFR signaling, in favor of the emergence of mesenchymal-like cancer cells during the development of aggressive prostate tumors. 相似文献
32.
Imaging the right heart pulmonary circulation unit: Insights from advanced ultrasound techniques 下载免费PDF全文
Francesco Ferrara MD PhD Luna Gargani MD PhD Ellen Ostenfeld MD Michele D'Alto MD PhD Jaroslaw Kasprzak MD Damien Voilliot MD Christine Selton‐Suty MD Olga Vriz MD Alberto M. Marra MD Paola Argiento MD Anna A. Stanziola MD PhD Antonio Cittadini MD PhD Antonello D'Andrea MD PhD Eduardo Bossone MD PhD 《Echocardiography (Mount Kisco, N.Y.)》2017,34(8):1216-1231
The right heart pulmonary circulation unit (RH‐PCU) is a key determinant of prognosis in several cardiorespiratory diseases. Although right heart catheterization is considered the gold standard for pulmonary hemodynamic assessment, a comprehensive cardiovascular ultrasound approach is an essential step in the diagnostic–prognostic clinical pathway of patients with suspect or overt pulmonary hypertension. The exponential development of advanced ultrasound techniques (strain, 3‐dimensional echocardiography and lung ultrasound) has led to new insights into the evaluation of RH‐PCU structure and function, overcoming some limitations of standard Doppler echocardiography. In the near future, exercise Doppler echocardiography may become a useful technique for detecting a latent stage of pulmonary hypertension and for evaluating right ventricular contractile reserve. 相似文献
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Emma Kanbar Damien Fouan Charles A. Sennoga Alexander A. Doinikov Ayache Bouakaz 《Ultrasound in medicine & biology》2017,43(5):1004-1015
Subharmonic signals backscattered from gas-filled lipid-shelled microbubbles have generated significant research interest because they can improve the detection and sensitivity of contrast-enhanced ultrasound imaging. However, the emission of subharmonic signals is strongly characterized by a temporal dependence, the origins of which have not been sufficiently elucidated. The features that influence subharmonic emissions need to be identified not only to better develop next-generation microbubble contrast agents, but also to develop more efficient subharmonic imaging (SHI) modes and therapeutic strategies. We examined the effect of microbubble filling gas on subharmonic emissions. Phospholipid shelled-microbubbles with different gaseous compositions such as sulfur hexafluoride (SF6), octafluoropropane (C3F8) or decafluorobutane (C4F10), nitrogen (N2)/C4F10 or air were insonated using a driving frequency of 10 MHz and peak negative pressure of 450 kPa, and their acoustic responses were tracked by monitoring both second harmonic and subharmonic emissions. Microbubbles were first acoustically characterized with their original gas and then re-characterized after substitution of the original gas with air, SF6 or C4F10. A measureable change in intensity of the subharmonic emissions with a 20- to 40-min delayed onset and increasing subharmonic emissions of the order 12–18 dB was recorded for microbubbles filled with C4F10. Substitution of C4F10 with air eliminated the earlier observed delay in subharmonic emissions. Significantly, substitution of SF6 for C4F10 successfully triggered a delay in the subharmonic emissions of the resultant agents, whereas substitution of C4F10 for SF6 eliminated the earlier observed suppression of subharmonic emissions, clearly suggesting that the type of filling gas contained in the microbubble agent influences subharmonic emissions in a time-dependent manner. Because our agents were dispersed in air-stabilized phosphate-buffered saline, these results suggest that the diffusivity of the gas from the agent to the surrounding medium is correlated with the time-dependent evolution of subharmonic emissions. 相似文献
34.
Procalcitonin and C‐reactive protein may help to detect invasive bacterial infections in children who have fever without source 下载免费PDF全文
35.
Noa Holoshitz Damien Kenny Ziyad M Hijazi 《Methodist DeBakey Cardiovascular Journal》2014,10(2):93-98
The evolution of congenital cardiac surgery has seen significant innovative advances in collaborative efforts between congenital cardiac surgeons and interventionalists to provide the least invasive intervention with the greatest hemodynamic benefit for patients with congenital heart disease. This review looks at how this collaborative approach has evolved and is being applied to treat a number of congenital conditions across the age ranges. 相似文献
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Nina Vyas Kawa Manmi Qianxi Wang Ananda J. Jadhav Mostafa Barigou Rachel L. Sammons Sarah A. Kuehne A. Damien Walmsley 《Ultrasound in medicine & biology》2019,45(5):1044-1055
Bacterial biofilms are a cause of contamination in a wide range of medical and biological areas. Ultrasound is a mechanical energy that can remove these biofilms using cavitation and acoustic streaming, which generate shear forces to disrupt biofilm from a surface. The aim of this narrative review is to investigate the literature on the mechanical removal of biofilm using acoustic cavitation to identify the different operating parameters affecting its removal using this method. The properties of the liquid and the properties of the ultrasound have a large impact on the type of cavitation generated. These include gas content, temperature, surface tension, frequency of ultrasound and acoustic pressure. For many of these parameters, more research is required to understand their mechanisms in the area of ultrasonic biofilm removal, and further research will help to optimise this method for effective removal of biofilms from different surfaces. 相似文献
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