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Recently, there has been an increasingly minimalistic approach to transcatheter aortic valve replacement (TAVR), with most procedures now performed under conscious sedation without real time transesophageal echocardiography (TEE) guidance. Proponents of echo should not feel discouraged by this; it is the initial insights that were gained with procedural TEE during the early years of TAVR that have allowed the procedure's gradual maturation and sophistication. Experienced centers that have promoted extensive TAVR TEE programs continue to maximize the benefits of echocardiography in both procedural planning and execution. Critical to this is the understanding of 3D TEE, allowing the annulus to be sized accurately, relevant neighboring anatomy defined, and complications flagged. This review will outline the current application of 3D TEE in TAVR and discuss challenges and opportunities for 3D echocardiography in this field.  相似文献   
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Inadvertent endocardial lead malposition is recognized as a rare incident which is usually underreported and if recognized during implantation can be easily corrected. This phenomenon is caused by the ventricular lead unintentionally crossing a pre-existing patent foremen ovale, septal defects (atrial or ventricular) or directly from the aorta via an accidental subclavian puncture resulting in the lead implanting into the left ventricle. While this is a rare occurrence we report, the incidental finding of pacemaker lead malposition during a routine follow-up transthoracic echocardiogram and the benefits of three-dimensional transesophageal echocardiography in this patient prior to lead extraction.  相似文献   
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Epstein–Barr virus (EBV) is a human B‐lymphotropic herpes virus and one of the most common viruses in humans. Specific skin signs related to EBV infection are the exanthem of mononucleosis, which is observed more frequently after ingestion of amoxicillin, and oral hairy leukoplakia, a disease occurring mostly in immunocompromised subjects with HIV infection. Other more uncommon cutaneous disorders that have been associated with EBV infection include virus‐related exanthems or diseases such as Gianotti–Crosti syndrome, erythema multiforme, and acute genital ulcers. Other skin manifestations, not correlated to virus infection, such as hydroa vacciniforme and drug‐induced hypersensitivity syndrome have also been linked to EBV. The putative involvement of EBV in skin diseases is growing similarly to other areas of medicine, where the role of EBV infection is being investigated in potentially debilitating inflammatory diseases. The prognosis of EBV infection in healthy, immunocompetent individuals is excellent. However, lifelong infection, which is kept in check by the host immune system, determines an unpredictable risk of pathologic unpredictable scenarios. In this review, we describe the spectrum of non‐tumoral dermatological manifestations that can follow EBV primary infection or reactivation of EBV in childhood.  相似文献   
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Castrated or sham-operated male athymic mice were inoculated with cells from the human hepatocellular carcinoma cell line PLC/PRF/5. There were no significant differences between the two groups with respect to the number of animals developing tumors, the time to tumor development, or the subsequent rate of increase in either tumor base area or mouse serum alpha-fetoprotein concentration. Androgen receptors were assayed in nuclei obtained from three separate liver cancer cell lines and from normal adult human liver. Similar concentrations, ranging from 235 to 550 fmol/mg DNA, of nuclear androgen receptors were detected in all tissues. Low percentages of androgen receptors were retained on DNA-cellulose. Although the presence of receptors implies the potential for metabolic effects of androgens in normal and malignant liver, our in vivostudies suggest that castration does not alter significantly the growth of liver cancer xenografts in athymic mice.  相似文献   
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