排序方式: 共有63条查询结果,搜索用时 15 毫秒
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通过采集严重骨盆髋臼骨折患者的薄层CT扫描数据, 在Mimics中进行图像编辑、三维重建及分析总结, 探讨3D打印技术在严重骨盆髋臼骨折内固定手术中的应用. 结果表明, 3D打印技术有利于术前进行手术设计、术前预弯钢板, 有利于判断畸形及术中在确定截骨部位、复位的关键标记以及判断复位质量. 3D打印技术具有快速性、高仿真性、高成功率及通用性意义, 具有推广价值. 相似文献
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Wensheng Zhang Wenjing Xu Fei Zhang Hui Jin Yuzhe Wang Jitao Li 《Research on Chemical Intermediates》2014,40(4):1337-1344
Treatment of a variety of arynes in water-soluble ionic liquid [DMIM]Me2PO4 in the presence of catalytic amount of CuI and inexpensive NH3·H2O under aerobic conditions afforded the corresponding symmetrical 1,3-diynes in high yields. The ionic liquid could be reused for at least five times without apparent decrease of the yield. 相似文献
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《Tetrahedron: Asymmetry》2005,16(5):959-963
A new series of thioether–phosphinite ligands, easily prepared in a few steps from inexpensive d-(+)-xylose, was tested in the Pd-catalyzed allylic substitution of substrates with different steric properties. The results show that the enantiomeric excesses are strongly dependent on the steric properties of the substituent in the thioether moiety. Enantiomeric excesses of up to 93% with high activities were obtained for the substrate rac-1,3-diphenyl-3-acetoxyprop-1-ene 7 with dimethyl malonate as the nucleophile. 相似文献
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本文旨在评估髓芯减压联合陶瓷骨植入治疗股骨头坏死的临床疗效, 并与单纯髓芯减压手术进行对比. 纳入第一作者所在医院骨科自2015年1月至2017年8月收治的早期股骨头坏死患者32例(40髋). 采用随机数表法将患髋随机分为A、B两组: A组20例, 行单纯髓芯减压术; B组20例, 行髓芯减压联合陶瓷骨植入手术. 术后每3个月通过影像学检查及查体对患者进行随访, 依据X线片结果将影像学分为进展及稳定两个等级. 髋关节功能评分采取Harris评分(Harris Hip Score, HHS). 记录两组数据并进行对比分析. 所有手术均顺利, 无围手术期严重并发症发生. 单纯髓芯减压组12髋(60.0%)影像学稳定, 髓芯减压联合陶瓷骨植入组18髋(90.0%)影像学稳定, 二者具有统计学差异(p=0.032). 两组术后HHS均较术前明显提高, 髓芯减压联合陶瓷骨植入组术后平均HSS为92.1分, 显著优于单纯髓芯减压组(HHS: 82.2, p=0.008). 按照HHS评分等级, 髓芯减压联合陶瓷骨植入组髋关节功能优良率为95.0%, 显著高于单纯髓芯减压组(70.0%, p=0.046). 髓芯减压联合陶瓷骨植入手术的临床疗效优于单纯髓芯减压手术, 可以作为治疗早中期股骨头坏死的有效方法. 相似文献
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在骨-器械界面建立和维持成熟骨是骨科植入材料长期成功的关键. 镁合金由于其生物可降解性、天然骨组织的力学相似性以及成骨潜力, 并且在体内不抑制间充质干细胞(hBMSCs)的成骨特性, 成为有前途的承重骨科植入物的候选材料. 但其高降解率和植入物相关感染的风险以及不佳的力学性能, 对其临床应用提出了巨大的挑战. 有限元分析方法能对复杂结构、形态、载荷和材料力学性能进行应力分析, 可有效地帮助临床医生了解镁合金植入器械的应力及生物力学性能. 相似文献
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设gφ,b是Littlewood-Paley g-函数与b生成的交换子.本文证明了若α,β属于Muckenhoupt A_p权函数类,1
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Rui-Hua Xiao Zhan-Ying Guo Shi-Qun Zhu Jian-Xing Fang 《International Journal of Theoretical Physics》2013,52(6):1721-1728
The dynamical behaviors of quantum discord between two atoms coupled with a vacuum cavity are investigated. If the two qubits are initially prepared in two extended Werner-like states, the quantum discord and entanglement can be numerically calculated. There are remarkable differences between the time evolutions of the quantum discord and entanglement under the same conditions. These results imply that quantum discord is not zero for some unentangled states and in some regions entanglement can disappear completely. A large amount of quantum discord exists between the two-qubit. Thus, the quantum discord is more robust than entanglement for the quantum system exposed to the environment. The quantum discord shows sudden change and its existence depends on the initial state of the system. This property of quantum discord may have important implications for experimental characterization of quantum phase transitions. 相似文献