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81.
目的 探讨无脑部外伤与骨科相关的意识障碍原因、鉴别诊断和治疗方法.方法 回顾性分析自2003-01-2014-01诊治的77例无脑部外伤骨科患者出现意识障碍的临床资料.结果 本组68例获得随访6~128个月,平均67.6个月.其中脂肪栓塞综合征(FES)33例中死亡2例,植物状态1例,13例昏迷2~10周,17例表现为较轻的意识障碍,24例目前意识均恢复正常.肺栓塞(PE)21例中死亡9例,植物状态2例,4例昏迷2~5 d,6例出现短暂的意识丧失,8例目前意识恢复正常.脑梗死(CI)9例中死亡3例,植物状态1例,4例遗留部分后遗症.重度低钠血症(SHN)7例,意识均恢复正常.重症肺炎(SP)5例中死亡4例,1例意识恢复正常.颅内感染(ICI)2例,均死亡.结论 无脑部外伤的骨科患者出现的意识障碍要充分认识,辨明病因,积极防治,减少死亡率和病残率.  相似文献   
82.

Purpose

Percutaneous epiphysiodesis using transphyseal screws (PETS) was developed as a minimally invasive outpatient procedure to address limb-length discrepancy (LLD) that allowed immediate postoperative weight bearing and was potentially reversible by removing the screws. The aims of our study were to report our results using PETS for LLD and evaluate the accuracy of three growth predictor models.

Methods

Sixteen patients with an average age of 14 years were treated for LLD using PETS. Thirteen patients had screws inserted in a parallel fashion and 3 had crossed screws. We compared the predicted LLD at skeletal maturity using the three growth predictor methods with the actual LLD at skeletal maturity and preoperative LLD with the final LLD at skeletal maturity.

Results

The mean LLD at skeletal maturity between the predicted and final measurements was 0.2 cm using the Green−Anderson method, 1.4 cm using the Moseley method, and −0.1 cm using the Paley method. The mean preoperative LLD of 3.1 cm was corrected to 1.7 cm at skeletal maturity (p < 0.001). Six patients complained of pain over the screw heads; however, no patient developed an infection or angular deformity.

Conclusions

The three growth predictor methods predicted the final LLD within an average of 1.4 cm, but there was high variability. Although PETS improved the LLD by a mean of 1.4 cm, we believe the results would have been better if PETS was performed at an earlier skeletal age.  相似文献   
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Nanotechnology is a very attractive tool for tailoring the surface of an orthopedic implant to optimize its interaction with the biological environment. Nanostructured interfaces are promising, especially for orthopedic applications. They can not only improve osseointegration between the implant and the living bone but also may be used as drug delivery platforms. The nanoporous structure can be used as a drug carrier to the surrounding tissue, with the intention to accelerate tissue–implant integration as well as to reduce and treat bacterial infections occurring after implantation. Titanium oxide nanotubes are promising for such applications; however, their brittle nature could be a significantly limiting factor. In this work, we modified the topography of commercially used titanium foil by the anodization process and hydrothermal treatment. As a result, we obtained a crystalline nanoporous u-shaped structure (US) of anodized titanium oxide with improved resistance to scratch compared to TiO2 nanotubes. The US titanium substrate was successfully modified with hydroxyapatite coating and investigated for bioactivity. Results showed high bioactivity in simulated body fluid (SBF) after two weeks of incubation.  相似文献   
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Aim: To investigate the effect of calcium concentration on the bone tissue response to Ca‐incorporated titanium implants Materials and methods: Two titanium surfaces containing 4.2% and 6.6% calcium were prepared using the micro‐arc oxidation process. The implants were inserted in the tibia of nine New Zealand White rabbits. After 6 weeks of healing, the bone response to the implants was quantitatively compared by biomechanical and histomorphometrical measurements. Results: Ca 4.2% and Ca 6.6% containing implants revealed no distinctive differences in their qualitative surface chemistry; chemical bonding state of Ca in titanium oxide was mainly calcium titanates. No significant differences were observed between two implants in peak removal torque and shear strength comparisons (P>0.05). Histomorphometrical analyses presented no significant differences in bone–metal contact, bone area and newly formed bone measurements between two implants (P>0.05). Conclusions: From biomechanical and histomorphometrical measurements, the two calcium concentrations in this study did not differ significantly with respect to their influence on the bone tissue response. This similar bone response in rabbit tibiae may be explained by the similarity of the qualitative Ca chemistry in titanium surfaces.  相似文献   
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刘晓  廖光天  李慧慧 《口腔医学研究》2012,28(9):865-867,871
目的:冷热循环对不同金属与树脂粘接剂粘接强度的影响。方法:铸造直径分别为4mm和5mm的镍铬合金和纯钛,切割成长度为3mm的标本。2种规格的同种金属标本配对,金属表面经50μmAlzO3喷砂,涂布Al—loy Primer,使用Super—BondC&B和PanaviaF2种粘接剂粘接。固化后经37℃恒温水浴24h以及10000次冷热循环,测试剪切粘接强度。用spssl7.0统计软件进行统计分析。结果:10000次冷热循环后,镍铬合金与Super—BondC&B、纯钛与PanaviaF粘接强度显著提高(P〈O.01),其余各组没有统计学差异。结论:粘接剂的种类对冷热循环前后的粘接强度没有明显影响,金属的种类对冷热循环前后的粘接强度没有明显影响,但是不同金属和不同粘接剂的配伍组合在冷热循环前后的粘接强度变化有统计学意义。  相似文献   
90.
目的改变纯钛表面的成分,提高其硬度和耐磨损性能。方法对纯钛试样表面行3×1017 ions.cm-2和9×1017 ions.cm-2两种剂量的氮离子注入。以能量散射光谱测定分析其表面元素的改变,显微硬度仪测量其显微硬度,纳米划痕仪测量其表面的耐磨损性能,扫描电子显微镜观察其注入前后的划痕形貌。综合分析其微观摩擦学性能的改变。结果氮离子注入后,纯钛试样表面成金黄色。在注入3×1017 ions.cm-2和9×1017 ions.cm-2剂量的氮离子试样表面,氮元素的原子百分率分别为24.08%和35.83%。试样表面的显微硬度值提高。纯钛的摩擦系数较氮离子注入前明显降低,其中注入剂量为9×1017 ions.cm-2的纯钛较剂量为3×1017 ions.cm-2的纯钛摩擦系数小。结论氮离子注入可提高纯钛的硬度,改善其耐磨损性能。  相似文献   
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