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How memory is retained is an immunological mystery. One possibility, argued here by Fons UytdeHaag and colleagues, is that memory is imprinted in the somatically-mutated Ig expressed by certain CD5+ B cells. The theory proposes that the Ig expressed by this self-renewing population acts as surrogate antigen, selecting and stimulating emerging antigen-specific lymphocytes.  相似文献   
94.
A 12‐year‐old child presented with recurrent respiratory infections and was diagnosed with Scimitar syndrome. Drainage of IVC and course of aberrant arterial supply from aorta were not clear by echocardiogram, and hence, additional imaging was planned. CT unraveled the presence of a rare combination of anomalous pulmonary venous connection (APVC) to IVC, with near‐atresia/severe stenosis of IVC, superior to the drainage of scimitar vein. There was a prominent azygos vein with preferential contrast opacification on lower limb injection.  相似文献   
95.
Intermittent dysfunction of mechanical mitral valve prosthesis is an uncommon condition. It carries serious clinical implications if unrecognized. Here, we present a case of a 28‐year‐old female with a history of rheumatic multivalvular disease, for which she had undergone double valve replacement and tricuspid annuloplasty. Six months later, she presented with heart failure. Clinical examination revealed intermittent loss of closing clicks followed by a pansystolic murmur at the apex, suggestive of mitral prosthetic valve dysfunction. We highlight the echocardiographic findings of paroxysmal mitral valvular regurgitation secondary to prosthetic valve malfunction secondary to prosthetic valve thrombosis.  相似文献   
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Patients with large sub-pulmonic ventricular septal defect (VSD) present early as a results of their complications. Some present late, due to the restriction of VSD by the right coronary cusp (RCC) due to its prolapse. In this report, we present a rare case of sub-pulmonic VSD in a 33-year-old man who developed a sub-pulmonic stenosis due to the prolapse of the RCC into the right ventricular outflow tract.  相似文献   
98.
Accurate assessment of etiology of mitral regurgitation (MR) is one of the key steps in the decision-making process and further clinical management of patients with severe MR. Our clinical case illustrates the added value of three-dimensional echocardiography (3DE) in assessment of mitral valve morphology and identification of an unexpected mechanism of MR which was not previously diagnosed using conventional echocardiography. 3DE helped to choose appropriate management strategy in this patient.  相似文献   
99.
Saline contrast echocardiography is a simple and effective method to diagnose the presence and type of right-to-left shunt in patients with unexplained cyanosis. It is considered a very sensitive test to diagnose pulmonary arteriovenous malformations. Our patient presented with unexplained cyanosis and transthoracic echocardiography showed an atrial septal defect and anomalous pulmonary venous drainage of the right and left upper pulmonary veins to the superior venacava. We describe how we used saline contrast echocardiography to demonstrate the presence of pulmonary arteriovenous malformations even in the presence of atrial septal defect and anomalous pulmonary venous drainage.  相似文献   
100.
In cor triatriatum sinister, the left atrium is divided by a membrane into a proximal and a distal chamber. Usually proximal chamber receives all the pulmonary veins and drains through an opening in the dividing membrane into distal chamber, which empties into left ventricle through the mitral valve. Rarely, the two chambers lack a communication and there is associated total anomalous pulmonary venous connection (TAPVC). We report a 1-month-old infant with cyanosis and heart failure, who had cor triatriatum sinister associated with supracardiac TAPVC. The case is reported for rarity of the association with a focus on contrast echocardiographic imaging.  相似文献   
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