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背景:成人髋臼发育不良晚期并发髋关节骨性关节炎常需行全髋关节置换。由于不同患者髋臼病变的严重程度有很大差别,导致重建髋臼时难度明显增加,而髋臼内壁内移截骨能良好解决对臼杯假体的包容,但对截骨后髋臼内壁的内移范围仍存有争议。
目的:通过计算机辅助设计有限元分析,寻找髋臼内壁截骨的合适内移范围。
方法:利用SolidWorks 2008软件建立髋臼发育不良骨盆的三维模型,模拟髋臼内壁内移截骨术式,使髋臼内壁骨从未完全陷入盆腔内保持2 mm骨性接触处开始,逐渐内移至完全陷入盆腔内7 mm处,每隔1 mm为1个实验组,分成10个实验组。将每组髋臼人为划成4个象限,分别对各组假体髋臼-骨界面间进行计算机模拟对比力学实验分析,测量出髋臼假体-骨界面间的Mises应力及剪切应力值。
结果与结论:第1,5,6,9,10组在后下、前上、前下3个象限内的Mises应力分布不均匀;第2,3,4,7,8 组在后下、前上、前下3个象限内的Mises应力分布均匀,其中第4组Mises应力分布更为均匀。第2,3,4,7,8组在上述3个象限内的剪切应力分布均匀,第7,8组剪切应力最小。提示关节力在髋臼内的分布主要集中在后上象限,随着臼杯不断内移,臼杯与骨的接触面积会逐渐增大,从而增加接触面上的Mises应力,但剪切应力随髋臼内壁的内移而减小。因此髋臼内壁截骨合适的内移范围在未入盆腔内1 mm到完全陷入盆腔1 mm,最佳位置在完全陷入盆腔1 mm处。 相似文献
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目的: 探讨RNA干扰技术沉默STAT3基因表达对人肝癌细胞的抑制作用及对相关生长调控基因的调节.方法:构建pSilencer 3.0-H1-siRNA-STAT3重组质粒, 转染人肝癌细胞株SMMC 7721, 采用MTT法观察重组质粒对肝癌细胞的生长抑制, RT-PCR和Western blot及免疫组化法分别观察STAT3基因和蛋白水平的变化, 同时检测 survivin, c-myc, VEGF, p53, caspase3生长调控基因的mRNA, 并用流式细胞技术(FCM)及AO/EB染色方法观察细胞凋亡.结果: pSilencer 3.0-H1-siRNA-STAT3重组质粒对肝癌细胞的生长有抑制作用, 实验组48 h和72 h抑制率分别为59.32%, 76.49%, 与空白组及阴性组细胞相比有显著性差异(P<0.01);在重组质粒组, STAT3基因mRNA及蛋白水平表达降低, surviving, VEGF的mRNA表达下调, p53, caspase3的mRNA表达上调(P<0.01), c-myc的mRNA表达却无明显改变;重组质粒可诱导SMMC 7721细胞凋亡, 凋亡率达21.6%(P<0.01), 细胞周期分析显示细胞阻滞于G2期.结论:pSilencer 3.0-H1-STAT3-siRNA可能通过下调基因survivin和VEGF mRNA表达, 上调p53和caspase3 mRNA表达来抑制STAT3基因在人肝癌细胞中的表达. 相似文献
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Penetrating injuries are rare but important for the patient both visually and socioeconomically. This guide intends to provide a structure for emergency department personnel to enable targeted history taking, effective examination, appropriate investigation and timely referral for those presenting with penetrating eye trauma. 相似文献
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BackgroundKidney transplant recipients are at increased risk of keratinocyte cancers, namely squamous cell and basal cell carcinomas (SCCs and BCCs). This is primarily due to the high levels of immunosuppression that are required to prevent allograft rejection. Different immunosuppressive medications confer different risks, and the effect of mycophenolate mofetil on SCC and BCC risk is unclear. We explored the relationship between mycophenolate dose prescribed over the entire transplant period and the risk of SCC and BCC.MethodsKidney transplant recipients from Queensland, Australia, were recruited between 2012 and 2014 and followed until mid-2016. During this time transplant recipients underwent regular skin examinations to diagnose incident SCCs and BCCs. Immunosuppressive medication regimens were obtained from hospital records, and the average mycophenolate dose/day over the entire transplantation period was calculated for each patient. Doses were divided into three ranked groups, and adjusted relative risks (RRadj) of developing SCC and BCC tumours were calculated using negative binomial regression with the lowest dosage group as reference. Recipients who had used azathioprine previously were excluded; further sub-group analysis was performed for other immunosuppressant medications.ResultsThere were 134 kidney transplant recipients included in the study. The average age was 55, 31% were female and 69% were male. At the highest median mycophenolate dose of 1818 mg/day the SCC risk doubled (RRadj 2.22, 95% CI 1.03–4.77) when compared to the reference group of 1038 mg/day. An increased risk persisted after accounting for ever-use of ciclosporin, ever-use of tacrolimus, and when excluding mammalian target of rapamycin users. This increased risk was mainly carried by kidney transplant recipients immunosuppressed for five or more years (RRadj = 11.05 95% CI 2.50–48.81). In contrast, there was no significant association between BCC incidence and therapy with the highest compared with the lowest mycophenolate dosage (RRadj = 1.27 95% CI 0.56–2.87).ConclusionHigher mycophenolate dosage is associated with increased SCCs in kidney transplant recipients, particularly those immunosuppressed for more than five years. The increased SCC risk persists after accounting for usage of other immunosuppressant medications. 相似文献
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目的检测同种异体间充质干细胞在不接受免疫抑制治疗的正常羊关节腔内分化形成软骨能力。方法将同种异体间充质干细胞复合β-磷酸三钙陶瓷植入正常羊关节腔内。在进行干细胞体内植入前进行淋巴细胞混合试验,确保供体与受体动物间存在免疫排斥反应。异体干细胞植入8周后,取出植入物进行组织学与免疫组化分析。将其结果与自体间充质干细胞复合β-磷酸三钙陶瓷关节腔内植入以及无细胞复合的单纯β-磷酸三钙陶瓷关节腔内植入相应检测结果进行对比分析。通过检测受体血清内产生的针对供体细胞的特异性抗体,评估系统性免疫反应。结果未检测到针对同种异体间充质干细胞移植所产生的特异性免疫排斥反应。在复合异体干细胞的植入物内没有发生明显炎性细胞浸润,并且没有检测到有针对异体细胞的抗体产生。组织学和免疫组化分析表明在复合异体及自体间充质干细胞的植入物内有新生软骨形成。在无细胞复合的植入物内未检测到软骨形成。结论受关节腔环境影响,同种异体间充质干细胞能够分化形成软骨组织。在被移植到不经免疫抑制治疗的同种异基因动物体内后,细胞陶瓷复合体不引起特异性免疫排斥反应。 相似文献
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免疫磁珠法分离纯化骨髓间充质干细胞及向成软骨细胞分化 总被引:5,自引:1,他引:5
目的利用免疫磁珠法分离成人骨髓神经生长因子受体(nerve growth factor receptor,NGFR)阳性细胞,获得同质性骨髓间充质干细胞(bone m esenchymal stem cells,BMSCs),并进行向软骨细胞诱导。方法采用Percoll密度梯度离心法分离成人骨髓中单个核细胞(mononuclearcells,MNCs),对MNCs进行常规贴壁培养或应用磁分离技术分离NGFR+细胞。分别检测NGFR+细胞和常规贴壁培养所获BMSCs体外扩增和集落形成能力,分析其细胞表型和细胞周期,并进行成神经细胞诱导。结果免疫磁珠分离获得NGFR阳性细胞的纯度为(90.6±5.1)%,NGFR阳性细胞较贴壁培养获得BMSCs具备更强增殖能力和向软骨分化潜能。结论利用免疫磁珠分离骨髓NGFR阳性细胞可以获得同质性原始BMSCs。 相似文献
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