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Introduction Myxopapillary ependymomas are low grade tumours that are known to recur locally even after complete excision, but metastasis to distant sites is extremely uncommon. Case report We report an unusual case of lumbo-sacral myxopapillary ependymoma in a 13-year-old boy with metastasis to both cerebellopontine angles. To the best of our knowledge, this is the youngest patient of metastatic myxopapillary ependymoma.  相似文献   
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Percutaneous retrograde puncture of the popliteal artery is a well-described technique and offers an alternative site for access to the peripheral vascular system. Antegrade popliteal artery puncture has only been described once in the literature. We present a case of subintimal angioplasty of a crural vessel occlusion using an antegrade popliteal approach. This report highlights that if other access is not possible due to unfavourable anatomy this approach is a technically feasible option.  相似文献   
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Summary. Cotton leaf curl disease (CLCuD) causing viruses belong to the Begomovirus genus of the family Geminiviridae. Most begomoviruses are bipartite with two molecules of circular single stranded DNA (A and B) encapsidated in icosahedral geminate particles. However, the begomoviruses associated with CLCuD have DNA- instead of DNA-B. In this communication we report the complete genomic sequence of DNA-A component of two CLCuD-causing begomoviruses, cotton leaf curl Kokhran virus-Dabawali (CLCuKV-Dab), tomato leaf curl Bangalore virus-Cotton [Fatehabad] (ToLCBV-Cotton [Fat]) and partial sequences of two other isolates cotton leaf curl Rajasthan virus-Bangalore (CLCuRV-Ban) and cotton leaf curl Kokhran virus-Ganganagar (CLCuKV-Gang). A phylogenetic analysis of these isolates along with other related begomoviruses showed that ToLCBV-Cotton [Fat] isolate was closest to the tomato leaf curl Bangalore virus-5 (ToLCBV-Ban5) where as CLCuKV-Dab isolate was close to the cotton leaf curl Kokhran virus-Faisalabad1 (CLCuKV-Fai1), cotton leaf curl Kokhran virus-72b (CLCuKV-72b) and cotton leaf curl Kokhran virus-806b (CLCuKV-806b) isolates from Pakistan. The phylogenetic analysis further showed that the ToLCBV-Cotton [Fat] and CLCuKV-Dab isolates along with CLCuKV-Fai1, CLCuKV-72b and CLCuKV-806b are closer to the ToLCBV, tomato leaf curl Gujarat virus (ToLCGV), tomato leaf curl Gujarat virus-Varanasi (ToLCGV-Var) and tomato leaf curl Sri Lanka virus (ToLCSLV) isolates, where as cotton leaf curl Alabad virus-804a (CLCuAV-804a), cotton leaf curl Multhan virus (CLCuMV) cluster with the isolates from cotton leaf curl Rajasthan virus (CLCuRV) and okra yellow vein mosaic virus (OYVMV). These results demonstrate the extensive variability observed in this group of viruses. The AC4 ORF is the least conserved among these viruses. In order to further asses the variability in the CLCuD-causing begomoviruses, the region showing minimum similarity in the DNA-A sequence was first determined by a comparison of segments of different lengths of the aligned sequences. The results indicated that region 2411–424 (771nt) was the least conserved. A phylogenetic tree constructed using the sequences of all the CLCuD causing begomoviruses, corresponding to the least conserved region showed that they form two distinct clusters.  相似文献   
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The management of the capsule during hip arthroscopy for femoroacetabular impingement syndrome has been in the spotlight during the last decade. Although there is robust biomechanical evidence that preserving the anatomic integrity of the iliofemoral ligament is important for the stability of the hip joint, the effect of capsular management on patient outcomes is often debated in clinical studies. Mid-term and long-term follow-up studies have shown that capsular closure is associated with decreased risk of hip arthroscopy failure, but no difference in patient outcomes based on capsular management has been found by some case series studies. What is driving the controversy in the literature? It seems to stem from the variation in surgical techniques used to perform hip capsulotomy or capsular repair, worldwide. Given that improvement in patient outcomes must be prioritized, it is time to use the existing knowledge appropriately to establish evidence-based guidelines for the management of hip capsule during hip arthroscopy.  相似文献   
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PurposeFractures of the femoral shaft in children are common. The rates of bone growth and remodeling in children vary according to their ages, which affect their respective management. MethodsThis paper evaluates the incidence and patterns of pediatric femoral shaft fracture and the current concepts of treatments available.ResultsThe type of fracture—closed or open; stable or unstable—needs to be taken into account. Child abuse should be suspected in fractures sustained by infants. For younger children, non-surgical management is preferred, which include Pavlik harness (< 6 months old) and early spica casting (6 months to 6 years old). Older children (> 6 years old) usually benefit from surgical treatments as outcomes of non-surgical alternatives are worse and are associated with prolonged recovery times. These operative measures for older children that are 6–12 years old include elastic stable intramedullary nailing and submuscular plating. Factors to be considered when devising an appropriate intervention include body mass, location of injury, and nature of fracture. For adolescent and skeletally mature teenagers (> 12 years old), rigid antegrade entry intramedullary fixation is indicated. In the event of open fractures or polytrauma, external fixation should be considered as a temporary treatment method for initial fracture stabilization.ConclusionAn age-based and evidence-based algorithm has been proposed to guide surgeons in the process of evaluating an appropriate treatment.  相似文献   
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A prospective vein graft screening programme was established in order to improve graft patency in the period 1-12 months after operation. Patient assessment consisted of ankle:brachial pressure index (ABPI) measurement before and after exercise, and Duplex scanning. Thirty-nine grafts have been followed up, with 19 stenoses detected in 18 grafts (46%) using Duplex. Of these 18 grafts, six had a serial fall in resting ABPI, median 0.14 (range 0.11-0.33), and nine had a post-exercise ABPI fall, median 0.19 (range 0.13-0.4). The remaining three had a normal ABPI but were unable to exercise. Fifteen grafts have been treated, 12 by percutaneous transluminal angioplasty (PTA), and three by surgery. One stenosis treated with PTA recurred within 3 months and was repaired with a vein patch. Since screening was implemented no grafts in the programme have occluded. This study indicates that simple ABPI measurements can be used to screen "at risk" grafts for evaluation with Duplex scanning, without jeopardising graft patency.  相似文献   
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