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131.
Background: Most children in need of cardiac pacemakers remain dependent on the function of the permanent from childhood to adulthood. We sought to evaluate and compare the function between epicardial and endocardial pacemakers in pediatric groups with different conditions. Methods: Between 2012 and 2018, this single-canter study evaluated 44 pediatric patients with indications for epicardial or endocardial pacemakers. Results: The 2 groups, at a median age of 5 (0.1–16) years, were compared concerning the characteristics of the leads used (n = 80: bipolar, unipolar, steroid-eluting, and non–steroid-eluting), survival data, and complications. The reason for pacemaker implantation was congenital complete heart block in 11 (25%) cases and postoperative heart block in 33 (75%) cases. The commonest congenital heart disease accompanied by postoperative block was the ventricular septal defect. In the endocardial lead group, the mean ventricular pacing threshold immediately after the implantation and during the follow-up was less than that in the epicardial lead group (0.75 vs. 0.81 V; P = 0.01 and 0.8 vs. 2.4 V; P = 0.001). During the follow-up, the mean battery longevity was better in the endocardial group (last visit: 6.7 endocardial vs. 3.3 years epicardial). Lead failure was commoner in the epicardial pacemaker, and chronic high-pacing threshold pattern was seen in 14 patients in this group. After 3 years, freedom from lead failure was 94% and 63% in the endocardial and epicardial leads. Conclusions: Pacemakers with endocardial bipolar steroid-eluting leads showed better lead characteristics regarding survival and battery longevity than epicardial pacemakers without these lead characteristics. An appropriate pacemaker type should be selected based on the patient’s condition.  相似文献   
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Annals of Nuclear Medicine - When using perfusion only modified PIOPED II criteria for PE detection, generated non-diagnostic scans are found to be the main diagnostic restriction. The objective of...  相似文献   
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Y-STR polymorphism of Gujjar population was determined by using AmpFISTR®YfilerTM PCR amplification kit. A total 176 haplotypes were obtained after the analysis of 17 Y-STR loci in 176 genetically unrelated individuals. Haplotype diversity and discrimination capacity attained was 0.99730 and 0.652201325, respectively. The comparison of Gujjar population with 16 other populations revealed that Gujjars have low genetic distance from Punjabi, Sindhi, and Pakhtun population of Pakistan; Azad Kashmir, Saraswat Brahmin from India; Bangladeshi population; north and south of Afghanistan; and Uttar Pradesh India which hints toward the migrational route Gujjars took over the centuries. This data is of significant value for population studies and forensic applications.  相似文献   
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Prediction of the diameter of a nanofiber is very difficult, owing to complexity of the interactions of the parameters which have an impact on the diameter and the fact that there is no comprehensive method to predict the diameter of a nanofiber. Therefore, the aim of this study was to compare the multi-layer perceptron (MLP), radial basis function (RBF), and support vector machine (SVM) models to develop mathematical models for the diameter prediction of poly(ε-caprolactone) (PCL)/gelatin (Gt) nanofibers. Four parameters, namely, the weight ratio, applied voltage, injection rate, and distance, were considered as input data. Then, a prediction of the diameter for the nanofiber model (PDNFM) was developed using data mining techniques such as MLP, RBFNN, and SVM. The PDNFMMLP is introduced as the most accurate model to predict the diameter of PCL/Gt nanofibers on the basis of costs and time-saving. According to the results of the sensitivity analysis, the value of the PCL/Gt weight ratio is the most significant input which influences PDNFMMLP in PCL/Gt electrospinning. Therefore, the PDNFM model, using a decision support system (DSS) tool can easily predict the diameter of PCL/Gt nanofibers prior to electrospinning.

A new tool for prediction the diameter of nanofibers is presented: the use of adaptive modeling techniques to predict fiber diameter and study the impact of electrospinning process parameters on electrospinning fiber diameter.  相似文献   
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Clinical Rheumatology - Rheumatoid arthritis (RA) is the most common autoimmune rheumatic disease, in which an epigenetic implication in the disease etiopathogenesis has been noted. Here in this...  相似文献   
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Clinical Rheumatology - Vitamin D is involved in immune system modulation as well as in calcium and bone homeostasis, hence plays a role in rheumatoid arthritis (RA) etiopathogenesis. A bulk of...  相似文献   
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