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1.
【摘要】目的:分析保乳术后放疗患者钛夹动度,并探讨其与乳腺大小、钛夹位置的相关性。方法:随机选取保乳术后放疗患者15例,每周两次锥形束CT。测量乳腺基底面直径(D)和乳高轴(H),以瘤床质心为原点将临床靶区分4个象限。记录各象限内钛夹在左右、腹背、头脚方向动度(MLR、MAP、MSI)以及其与临床靶区最内、最前、最上的距离(DSLR、DSAP、DSSI)。结果:MLR、MAP、MSI分别为(2.2±3.0)、(-1.1±3.6)、(0.8±4.7) mm;系统误差Σ在左、右、腹、背、头、脚分别为1.7、2.2、2.0、2.4、2.9、3.0 mm,随机误差σ分别为2.4、4.0、3.2、4.0、4.7、4.7 mm;靶区对应外放5.9、8.3、7.2、8.8、10.5、10.9 mm。一象限内,当D×H<99.89 cm2,MAP和D×H强相关(r=0.805),MLR、MAP均和DSLR、DSAP、DSSI强正相关(r=0.94, 0.94, 0.91;0.87, 0.91, 0.92),MSI和DSLR、DSAP强正相关(r=0.91, 0.94);四象限内,当D×H<90.71 cm2,MAP和DSLR,MSI和DSAP均强负相关(r=-0.96;-0.95),MLR和DSLR强正相关(r=0.91)。结论:钛夹动度有各向异性,以SI方向外扩最大,并易受乳腺大小、钛夹位置影响。  相似文献   
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By means of the ultrasonic surface impact (amplitude of 30 μm, strike number of 48,000 times/mm2), nanograins have been achieved in the surfaces of both Ti6Al4V(TC4) and Ti3Zr2Sn3Mo25Nb(TLM) titanium alloys, mainly because of the dislocation motion. Many mechanical properties are improved, such as hardness, residual stress, and roughness. The rotating–bending fatigue limits of TC4 and TLM subjected to ultrasonic impact are improved by 13.1% and 23.7%, separately. Because of the bending fatigue behavior, which is sensitive to the surface condition, cracks usually initiate from the surface defects under high stress amplitude. By means of an ultrasonic impact tip with the size of 8 mm, most of the inner cracks present at the zone with a depth range of 100~250 μm in the high life region. The inner crack core to TC4 usually appears as a deformed long and narrow α-phase, while the cracks in TLM specimens prefer to initiate at the triple grain boundary junctions. This zone crosses the grain refined layer and the deformed coarse grain layer. With the gradient change of elastic parameters, the model shows an increase of normal stress at this zone. Combined with the loss of plasticity and toughness, it is easy to understand these fatigue behaviors.  相似文献   
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文题释义:微弧氧化技术:是金属材料表面处理的一种技术,将金属材料(如,镁、铝、钛等)置于特定电解液中,通过弧光放电过程中瞬时的高温和高压条件产生结合于金属表面的陶瓷膜层,该种方法制备的涂层材料具有高硬度、耐磨的特点。  种植体:是针对于人体自身牙齿缺失而植入上下颌骨内的人工牙根。性能优良的种植体需要同时具备高强度、耐降解、生物相容性好的特性。目前复合材料类如金属表面添加陶瓷涂层材料,具有上述多种材料特性而被临床选择。 背景:采用普通电化学法可在钛及其合金表面制备纳米级羟基磷灰石涂层,但该涂层吸收降解缓慢,需要8-12周的时间。而微弧氧化可在复杂表面形成均匀薄膜,有利于细胞黏附和骨组织长入。 目的:探索微弧氧化羟基磷灰石涂层钛合金对成骨细胞增殖及骨向分化能力的影响。 方法:采用电化学法与微弧氧化法分别制备羟基磷灰石涂层钛合金材料,检测两种材料表面的接触角。将成骨细胞系hFOB1.19接种于两组羟基磷灰石涂层钛合金材料表面,培养48 h时,采用扫描电镜观察细胞在材料上的形态变化;培养1,12,24,48,72 h时,采用MTT法检测细胞增殖;培养1,3,5 d时,比较两组材料表面细胞计数与碱性磷酸活性;培养第5天,采用Western Blotting检测细胞内骨形态发生蛋白2和骨形态发生蛋白4表达。 结果与结论:①微弧氧化组材料表面的接触角小于电化学组[(66.5±2.2)°,(52.8±2.1)°,P=0.001 5)];②扫描电镜显示,电化学组成骨细胞形态不规则,胞体皱缩不饱满,与材料贴合较差;微弧氧化组细胞充分伸展,形态扁平,与材料贴合紧密;③微弧氧化组12-72 h的细胞增殖快于电化学组(P < 0.05),培养3,5 d的细胞计数多于电化学组(P < 0.05);④微弧氧化组培养1,3,5 d的细胞碱性磷酸酶活性高于电化学组(P < 0.05);⑤微弧氧化组骨形态发生蛋白2和骨形态发生蛋白4表达均高于电化学组(P < 0.05);⑥结果表明,微弧氧化羟基磷灰石涂层钛合金材料可促进成骨细胞的增殖及骨向分化能力。 ORCID: 0000-0003-2787-4667(王艳玲) 中国组织工程研究杂志出版内容重点:生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程  相似文献   
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杨晓  梅伟  张伟 《中国组织工程研究》2020,24(27):4328-4332
文题释义:可吸收棒、钛合金螺钉内固定:两者均属于MasonⅡ型桡骨头骨折螺钉内固定法,主要区别在于其制作材质不一样,前者是由聚乳酸制成的可吸收高分子聚合物,而后者为钛合金制成,需二次手术取出。桡骨头骨折Mason分类:Ⅰ型,为线状骨折,即无移位型骨折,骨折线可通过桡骨头边缘或呈劈裂状;Ⅱ型,为有移位的骨折,有分离的边缘骨折;Ⅲ型,为粉碎型骨折,移位或无移位或呈塌陷性骨折;Ⅳ型,为桡骨头骨折伴有肘关节脱位。 背景:目前切开复位内固定是治疗MasonⅡ型桡骨头骨折的有效方法,内固定的选择有螺钉、微型钢板、克氏针、可吸收棒或钉等,临床疗效报道不一致。 目的:对比可吸收棒或钛合金螺钉内固定治疗MasonⅡ型桡骨头骨折的临床疗效。方法:选择2016年1月至2017年2月四川省人民医院收治的桡骨头骨折患者25例,其中男16例,女9例,年龄38-61岁,均进行切开复位内固定治疗,其中13例的内固定材料为钛合金螺钉,另12例的内固定材料为可吸收棒。术后随访拍摄X射线片,确定骨折愈合时间。末次随访时,对比两组目测类比评分、肘关节活动度及肘关节功能Mayo评分与Broberg-Morrey 评分。该研究已通过四川省医学科学院·四川省人民医院伦理委员会的审批。结果与结论:①可吸收棒组、钛合金螺钉组的骨折愈合时间分别为(2.35±0.92),(2.10±0.47)个月,组间比较差异无显著性意义(P > 0.05);②末次随访时,两组间肘关节功能Mayo评分与Broberg-Morrey 评分比较差异均无显著性意义(P > 0.05);③末次随访时,两组间肘关节屈曲、伸直、旋后、旋前角度比较差异均无显著性意义(P > 0.05);④末次随访时,两组目测类比评分比较差异均无显著性意义(P > 0.05);⑤结果表明,可吸收棒与钛合金螺钉治疗MasonⅡ型桡骨头骨折的临床疗效相似,但可吸收棒避免了二次手术取出内固定及应力性遮挡等情况。 ORCID: 0000-0003-4778-7050(杨晓) 中国组织工程研究杂志出版内容重点:人工关节;骨植入物;脊柱;骨折;内固定;数字化骨科;组织工程  相似文献   
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Segmental mandibular defects require reconstruction. The fibula flap serves as a versatile flap in restoring mandibular contour and bony height. With the advances in computer-aided design and additive manufacturing technology, an innovative “one-piece” patient-specific reconstruction plate to facilitate double-barrel fibula flap shaping and bone securing was developed; the plate is described in this study. The “one-piece” plate is fabricated with individualized specifications and is mainly composed of three components: the long-bar reconstruction plate, a short-bar plate, and connecting bars. Our initial experiences showed that mandibular reconstructive surgery was greatly facilitated by the “one-piece” reconstruction plate for double-barrel fibula flap reconstruction and achieved satisfactory outcomes. A well-designed clinical trial is required to confirm the superiority of the “one-piece” reconstruction plate in the future. ClinicalTrials.gov registration: NCT03057223.  相似文献   
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目的探讨可调节部分钛听骨在II型鼓室成形术听力重建中的疗效。方法回顾分析95例慢性化脓性中耳炎患者(均为单耳发病),随机分为两组,实验组(47耳):应用可调节钛金属部分听骨赝复物(PORP)行开放式乳突根治术+II型鼓室成形术;对照组(48耳):应用固定型钛听骨PORP重建听骨链。术后所有患者均随访1年以上,术后3个月、1年时分别对比两组的手术前后听力变化(0.5、1、2、4 kHz)及有效率。结果①实验组中1耳钛听骨移位;1耳筋膜裂缝,纳入听力研究45耳。一期手术成功率为95.7%(45/47),对照组中2耳钛听骨移位、2耳筋膜裂缝,纳入听力研究44耳。一期手术成功率为91.7%(44/48);②实验组与对照组比较,术后3个月气骨导差比较,差异具有统计学意义(P<0.05);术后1年气骨导差比较,差异无统计学意义(P>0.05);③实验组与对照组有效率比较,差异无统计学意义(P>0.05)。结论可调节钛听骨应用于听骨链重建有独特优越性,术后3个月听力恢复优于固定型钛听骨,为中耳传音材料提供新的选择。  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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PurposeThe treatment of hemimandibular hyperplasia (HH) is difficult by performing condylectomy and orthognathic surgery in one stage. This study investigated the clinical feasibility of treating HH with computer-aided design and computer-aided manufacturing (CAD/CAM) cutting and drilling guides and the pre-bent titanium plates to improve the accuracy of operation to avoid condyle reconstruction.Methods12 patients diagnosed with HH were included in this study from 2014 to 2018. Conservative condylectomy and bimaxillary orthognathic surgery were performed in all patients. The CAD/CAM cutting and drilling guides and the pre-bent titanium plates were used to guide surgeries. Follow-up and radiographic examinations were performed. The difference between virtually simulated and postoperative models was measured.ResultsAll patients got satisfactory and stable results, without complications or obvious relapse during follow-up. Occlusion relationship, temporomandibular joint function and facial symmetry were improved obviously after surgery. Comparison between simulated plans and actual postoperative outcomes showed that the surgical plans were transferred accurately.ConclusionsCAD/CAM cutting and drilling guides and the pre-bent titanium plates described in this paper can help transferring the results from computer simulation to the operating room accurately. Conservative condylectomy can be operated exactly matching bimaxillary orthognathic surgery for treating HH, avoiding condyle reconstruction.  相似文献   
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