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Transplant ureteric stent insertion reduces the incidence of MUCs, but it is not known whether routine PSRGU is needed to detect unmasked MUCs. This study evaluated whether routine PSRGU in the pRTR is a useful tool to identify MUCs before they become clinically apparent. A retrospective analysis was undertaken of the clinical outcomes following elective stent removal from pediatric kidney‐only transplant recipients at two London centers between 2012 and 2016. Our policy was to perform PSRGU either routinely or urgently if there were concerning symptoms or biochemical evidence of renal allograft dysfunction. Elective stent removal was performed in 86% (97 of 113 pRTR), and 75 (77%) of whom had routine PSRGU at a median (IQR) of 6 (2‐8) days after stent removal. There were changes to management in 3 (4%) of pRTR with PSRGU identifying no MUC. Nineteen patients (25%) had urgent PSRGU, most commonly due to renal allograft dysfunction, at a median (IQR) of 5.5 (2.7‐12.3) days after stent removal. Of these, two pRTR required ureteric intervention. For our current practice of removing transplant stents at 4‐6 weeks post‐transplantation, our study has found no evidence to support routine PSRGU after elective stent removal.  相似文献   
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Central illustration: cumulative major adverse cardiac events (MACE) and bioresorbable vascular scaffold (BVS) thrombosis rates after 1, 2, 3, 4 and 5 years.
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A comparative study involving bimetallic nickel catalysts designed from disubstituted N,N,N′,N′‐tetra(diphenylphosphanylmethyl)benzene diamine bridging ligands is reported. Catalyst behavior is explored in the Kumada catalyst‐transfer polymerization (KCTP) using poly(3‐hexylthiophene) (P3HT) as the model system. The success of a controlled polymerization is monitored by analyzing monomer conversion, degree of polymerization, end‐group identity, and molecular weight distribution. The characterization of P3HT obtained from KCTP initiated with the bimetallic catalysts shows chain‐growth behavior; however, the presence of Br/Br end‐groups and broader molecular weight distribution reveals a reduced controlled polymerization compared to the commonly employed Ni(dppp)Cl2. The observed increase in intermolecular chain transfer and termination processes in KCTP initiation with the bimetallic catalysts can be attributed to a weaker Ni(0)‐π‐aryl complex interaction, which is caused by increased steric crowding of the coordination sphere.  相似文献   
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Titanium osteosynthesis is currently the fixation system of choice in maxillofacial traumatology. Biodegradable osteosynthesis systems have the ability to degrade in the human body. The aim of this study was to conduct a systematic review, with meta- and trial sequential analyses, to assess the efficacy and morbidity of biodegradable versus titanium osteosynthesis after maxillofacial trauma. MEDLINE, Embase, and CENTRAL were searched for randomized controlled trials and prospective and retrospective controlled studies. Five time periods were studied: perioperative, short-term (0–4 weeks), intermediate (6–12 weeks), long-term (>12 weeks), and overall follow-up. After screening 3542 records, 24 were included. All had a high risk of performance and detection bias due to the nature of the interventions. Meta-analysis showed no differences in efficacy or morbidity between biodegradable and titanium osteosynthesis. The risk of perioperative screw breakage was significantly higher (risk ratio 17.13, 95% confidence interval 2.19–34.18) and the symptomatic plate removal rate lower in the biodegradable group (risk ratio 0.11, 95% confidence interval 0.02–0.57), which was confirmed by the trial sequential analysis. The quality of evidence ranged from very low to moderate. Based on the narrative review and meta-analyses, current evidence shows that biodegradable osteosynthesis is a viable alternative to titanium osteosynthesis when applied in the treatment of maxillofacial trauma, with similar efficacy but significantly lower symptomatic plate removal rates. Perioperative screw breakage occurred significantly more often in the biodegradable group compared to the titanium group.  相似文献   
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PurposeTo retrospectively evaluate the safety and effectiveness of the Covera stent graft (SG) for the treatment of dysfunctional or thrombosed arteriovenous grafts (AVGs).Materials and MethodsWithin 29 months (February 2016–August 2018), 79 patients underwent Covera SG placement in the authors’ department for the treatment of dysfunctional AVGs. Data were available for 64 patients who underwent 64 procedures, using 64 devices. Minimum follow-up was 6 months, unless reintervention occurred. Mean follow-up was 277 days (6–923 days). Treatment characteristics were 51 cases with venous-graft anastomosis (VGA) stenosis (79.7%), 13 cases of puncture zone stenosis (20.3%), 14 cases of in SG stenosis (21.9%), 8 cases of pseudoaneurysm treatment (12.5%) (1 treatment area might have had more than 1 characteristic). Thirty-six patients presented with thrombosis (56.2%), and 31 of 64 case were de novo treatment areas (48.4%). Primary outcome measurements were technical success and post-intervention primary patency (PIPP) at 6 months, whereas secondary outcome measurements included factors influencing primary outcome.ResultsTechnical success was 100%. Median PIPP was 336 days, and 73.6% of treatment areas were patent at 6 months. There were no significant differences in terms of PIPP when de novo treatment areas were compared with restenotic areas (519 vs. 320 days, respectively; P = .1); patients who presented with versus those who presented without thrombosis (320 vs. 583 days, respectively; P = .07); puncture zone stenosis or elsewhere (329 vs. 686 days, respectively; P = .52); and VGA stenosis or elsewhere (336 vs. 335 days, respectively; P = .9).ConclusionsUse of the Covera SG for AVG treatment was safe and effective in every type of treatment area presented in this retrospective analysis.  相似文献   
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目的 :通过观察实验犬下腔静脉内放置可扩张性内支撑后血管的形态学变化 ,确定支撑的内皮化进程 ,以期为临床减少内支撑阻塞、合理应用抗凝剂提供组织学的依据。  方法 :在 14只杂种犬下腔静脉内放置金属内支撑 ,于术后 1个月起 ,逐月取下腔静脉作光镜和电镜检查。  结果 :术后 1个月左右 ,内支撑基本内皮化 ,5个月完成血管的重构。  结论 :早期抗凝治疗是防止内支撑阻塞的关键 ,首次提出内支撑放置后血管重构的现象  相似文献   
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