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The development of ultrasound contrast agents with excellent tolerance and safety profiles has notably improved liver evaluation with ultrasound(US)for several applications,especially for the detection of metastases.In particular,contrast enhanced ultrasonography(CEUS)allows the display of the parenchymal microvasculature,enabling the study and visualization of the enhancement patterns of liver lesions in real time and in a continuous manner in all vascular phases,which is similar to contrast-enhanced computed tomography(CT)and contrast-enhanced magnetic resonance imaging.Clinical studies have reported that the use of a contrast agent enables the visualization of more metastases with significantly improved sensitivity and specificity compared to baseline-US.Furthermore,studies have shown that CEUS yields sensitivities comparable to CT.In this review,we describe the state of the art of CEUS for detecting colorectal liver metastases,the imaging features,the literature reports of metastases in CEUS as well as its technique,its clinical role and its potential applications.Additionally,the updated international consensus panel guidelines are reported in this review with the inherent limitations of this technique and best practice experiences.  相似文献   
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Modern cardiac resynchronization therapy (CRT) device‐based threshold detection enables capture management and voltage output adjusting to combine consistent left ventricular (LV) pacing with acceptable battery drainage. The current technologies available for LV capture automatic confirmation in most cases require the evoked response, as well as “LV pace to right ventricular sense” algorithms. The LV pacing percentage counter may overestimate the CRT delivery which may be reduced due to pacing inhibition (by sensed LV activation) or inadequate capture due to subthreshold current or pacing into refractory tissue. Moreover, the LV threshold at implant and its behavior over time (as a marker of electrical viability) and the ineffective CRT issues (subthreshold stimulation or concealed loss of capture) are discussed. The purpose of the present review is to explore these new challenges regarding LV pacing automatic management.  相似文献   
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T‐cell help to B lymphocytes is one of the most important events in adaptive immune responses in health and disease. It is generally delivered by cognate CD4+ T follicular helper (TFH) cells via both cell‐to‐cell contacts and soluble mediators, and it is essential for both the clonal expansion of antibody (Ab)‐secreting B cells and memory B‐cell formation. CD1d‐restricted invariant natural killer T (iNKT) cells are a subset of innate‐like T lymphocytes that rapidly respond to stimulation with specific lipid antigens (Ags) that are derived from infectious pathogens or stressed host cells. Activated iNKT cells produce a wide range of cytokines and upregulate costimulatory molecules that can promote activation of dendritic cells (DCs), natural killer (NK) cells, and T cells. A decade ago, we discovered that iNKT cells can help B cells to proliferate and to produce IgG Abs in vitro and in vivo. This adjuvant‐like function of Ag‐activated iNKT cells provides a flexible set of helper mechanisms that expand the current paradigm of T‐cell–B‐cell interaction and highlights the potential of iNKT‐cell targeting vaccine formulations.  相似文献   
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Acute ST-elevation myocardial infarction(STEMI) usually results from coronary atherosclerotic plaque disruption with superimposed thrombus formation. Detection of coronary thrombi is a poor prognostic indicator,which is mostly proportional to their size and composition. Particularly,intracoronary thrombi impair both epicardial blood flow and myocardial perfusion,by occluding major coronary arteries and causing distal embolization,respectively. Thus,although primary percutaneous coronary intervention is the preferred treatement strategy in STEMI setting,the associated use of adjunctive antithrombotic drugs and/or percutaneous thrombectomy is crucial to optimize therapy of STEMI patients,by improving either angiographical and clinical outcomes. This review article will focus on the prognostic significance of intracoronary thrombi and on current antithrombotic pharmacological and interventional strategies used inthe setting of STEMI to manage thrombotic lesions.  相似文献   
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