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When performing epicardial ablation of ventricular tachycardia (VT), caution must be taken not to damage the coronary arteries. We report a case in which a new, nonfluoroscopic technique for incorporating an accurate, real‐time reconstruction of the main coronary vessels into a three‐dimensional electroanatomic map was used for epicardial VT ablation.  相似文献   
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Aim The effects of sensorineural hearing loss (SNHL) are often complicated by additional disabilities, but the epidemiology of associated disorders is not clearly defined. The aim of this study was to evaluate the frequency and type of additional neurodevelopmental disabilities in a sample of children with SNHL and to investigate the relation between these additional disabilities and the aetiology of deafness. Method One hundred children with severe/profound SNHL (60 males, 40 females; mean age 5y 7mo, SD 3y 6mo, range 8mo–16y) were investigated using a diagnostic protocol including neurodevelopmental, genetic, neurometabolic, and brain magnetic resonance imaging (MRI) assessment. Results Forty‐eight per cent of the sample exhibited one or more additional disabilities, with cognitive, behavioural–emotional, and motor disorders being the most frequent. The risk of additional disabilities varied according to the type of aetiology. Thirty‐seven out of 80 individuals with available MRIs showed signal abnormalities, in particular brain malformations (46%) and white matter abnormalities (54%). Frequency and type of disability were associated with aetiology (p=0.015) and MRI data (p<0.001). Interpretation A multidimensional evaluation, including aetiological, neurodevelopmental, and MRI investigation, is needed for planning therapeutic intervention, such as cochlear implantation in children with severe to profound hearing impairment. The aetiology of deafness is a relevant risk indicator for the presence of an associated disorder.  相似文献   
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The H-Ala-Arg-(Ala)6-Lys-OH sequence is a biologically interesting ‘difficult sequence’ presenting Nα-Fmoc deprotection and coupling problems. Different chemical conditions and synthetic strategies have been tested in order to overcome the problems due to sequence-dependent interactions. In particular, it was confirmed that different solvents in the deprotection step did not provide any significant improvement, but the use of a more efficient base in the deprotection mixture avoided insufficient unblocking of Nα-protecting group; problems due to partial coupling in the last steps of the synthesis were solved by double coupling techniques. Moreover, the synthesis of the model peptide was carried out using both ‘continuous flow’ and ‘batch’ techniques. The present results demontrate that on-line monitoring of the deprotection step by absorbance measurements represents a very effective tool to detect the onset of internal aggregations during the synthesis. © Munksgaard 1997.  相似文献   
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The protective role of large spontaeous portosystemic shunts in oesophageal varices bleeding due to portal hypertension in liver cirrhosis is still debated. A series of 20 consecutive patients with haemodynamically efficient collaterals involving the para-umbilical-epigastric venous route (evaluated by Echo-Doppler flowmetry) is reported. All patients presented absent or mild oesophageal varices at endoscopy. During a mean follow-up period of 23.5 months, no patient developed large varices or experienced variceal bleeding. Hepatic encephalopathy was present in 35% of patients. Haemodynamically efficient spontaneous portosystemic shunts may protect cirrhotic patients from the risk of oesophageal varices forming and bleeding. The diversion of large amounts of blood from portal to systemic circulation correlates with the higher trend of hepatic encephalopathy in these patients.  相似文献   
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External Iliac Artery Endofibrosis (EIAE) is an uncommon disease usually affecting young, otherwise healthy, patients. It usually involves cyclists but cases have been reported in other groups of endurance athletes. The external iliac artery is the most affected anatomical site but other locations are described too. The precise pathophysiology and long-term evolution of the disease still remain unknown. The diagnosis may be challenging and delayed as the patients usually present symptoms only in extreme conditions and physical and instrumental examinations may be normal at rest.We present two cases of young professional cyclists who suffered of exercise-induced leg pain which led them to reduce running. Both patients were firstly treated with balloon angioplasty that rapidly failed to improve their symptoms. The successive open surgery with endofibrosectomy and autologous saphenous vein closure patch completely resolved physical limitations.EIAE is a rare disease that can induce arterial stenosis, thrombosis, dissection and secondary atheroma. After-exercise ankle-brachial index represents a useful diagnostic criterion. Careful observation of angio-CT may strengthen the suspect. Knowledge of the these features allows a better pre-operative assessment and an early effective treatment. Surgical revascularization remains the gold standard approach.  相似文献   
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