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前路或前-后联合入路治疗下颈椎骨折脱位合并关节突交锁 预览
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作者 刘军 李伟伟 +3 位作者 弓立群 范亚一 段大鹏 卫文博 《临床骨科杂志》 2019年第3期257-260,共4页
目的探讨前路或前-后联合入路治疗下颈椎骨折脱位合并关节突交锁的疗效。方法手术治疗17例下颈椎骨折脱位合并关节突交锁患者,9例行前路切开(复位)内固定融合术,8例行前-后联合入路切开(复位)内固定融合术。记录手术时间和术中出血量,... 目的探讨前路或前-后联合入路治疗下颈椎骨折脱位合并关节突交锁的疗效。方法手术治疗17例下颈椎骨折脱位合并关节突交锁患者,9例行前路切开(复位)内固定融合术,8例行前-后联合入路切开(复位)内固定融合术。记录手术时间和术中出血量,观察并发症情况。采用VAS评分评估疼痛改善情况,采用ASIA脊髓损伤分级评估神经功能恢复情况。X线检查评价椎体复位、关节突解锁及颈椎曲度改善情况。结果患者均获得随访,时间12~47(21.6±8.6)个月。前路术式的手术时间为90~110(98.1±6.9) min,术中出血量为90~120(109.7±14.7) ml;前-后联合入路术式的手术时间为180~240 (212.4±16.7) min,术中出血量为380~580(443.3±70.4) ml。VAS评分:术后3个月较术前明显下降(P <0.01),末次随访较术后3个月进一步下降(P <0.01)。颈椎曲度:术后3个月及末次随访均较术前明显改善(P <0.05),且末次随访无明显丢失(P> 0.05)。末次随访时,患者脊髓神经功能ASIA评分均较术前显著改善;椎体滑脱及关节突交锁均得到满意复位。除1例脑脊液漏、5例吞咽不适及1例C5神经根麻痹外,无其他并发症发生。结论前路或前-后联合入路治疗下颈椎骨折脱位合并关节交锁的临床效果满意。 展开更多
关键词 前路 前-后路 颈椎骨折 脱位 关节突交锁
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Open reduction of a total talar dislocation: A case report and review of the literature 预览
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作者 Furkan Yapici Mehmet Coskun +2 位作者 Muhammet Coskun Arslan Erman Ulu Yunus Emre Akman 《世界临床病例杂志》 2019年第14期1850-1856,共7页
BACKGROUND Total talar dislocation (TTD) is very uncommon for many orthopedic surgeons and emergency/trauma specialists. Scarce cases of TTD have been reported, mainly in the form of open fracture-dislocation injury. ... BACKGROUND Total talar dislocation (TTD) is very uncommon for many orthopedic surgeons and emergency/trauma specialists. Scarce cases of TTD have been reported, mainly in the form of open fracture-dislocation injury. CASE SUMMARY We report a very rare injury of closed TTD with a follow-up period of 36 mo. Initial closed reduction was not successful because of a fractured highly unstable medial malleolus displaced into the ankle mortise, blocking the relocation of the talus. The patient was able to walk pain-free after the 3rd month of surgery. At the 36-mo follow-up, there were 10 degrees of flexion loss and 10 degrees of extension loss in the tibiotalar joint. Furthermore, 5 degrees of subtalar joint inversion-eversion loss was present. CONCLUSION Open reduction should be performed for closed TTDs unless closed reduction is successful. 展开更多
关键词 TOTAL talar DISLOCATION Pan-talar DISLOCATION TALUS Case REPORT
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无痛无汗症患儿骨骼损伤临床特征分析 预览
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作者 王庆利 胡光俊 +1 位作者 谈世刚 宋晓阳 《临床儿科杂志》 CAS CSCD 北大核心 2019年第3期200-202,共3页
目的探讨无痛无汗症骨骼损伤的临床特征。方法收集无痛无汗症病例23例,回顾性分析患者骨骼损伤的首发年龄、发生部位、反复发生次数、原因、治疗及预后。结果骨骼损伤多为无明显诱因的反复多部位发生,首发年龄多在3~6岁,发生部位多在下... 目的探讨无痛无汗症骨骼损伤的临床特征。方法收集无痛无汗症病例23例,回顾性分析患者骨骼损伤的首发年龄、发生部位、反复发生次数、原因、治疗及预后。结果骨骼损伤多为无明显诱因的反复多部位发生,首发年龄多在3~6岁,发生部位多在下肢。6岁以上患者骨骼损伤发生率为100%。结论无痛无汗症患者反复发生骨骼损伤,其原因可能是NTRK1基因突变导致的骨骼发育不良。 展开更多
关键词 无痛无汗症 骨折 关节脱位 NTRK1基因
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Is CT scan a predictor of instability in recurrent dislocation shoulder?
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作者 K.P.Shijith Munish Sood +1 位作者 Ajay Deep Sud Amresh Ghai 《中华创伤杂志:英文版》 CAS CSCD 2019年第3期177-181,共5页
Purpose: Glenoid bone defect and the defect on the posterior-superior surface of the humerus “Hill- Sachs lesion” are the commonly seen bony lesions in patients with recurrent dislocation shoulder. Computed tomograp... Purpose: Glenoid bone defect and the defect on the posterior-superior surface of the humerus “Hill- Sachs lesion” are the commonly seen bony lesions in patients with recurrent dislocation shoulder. Computed tomography (CT) scan is considered as the best option in assessing the bony defects in the recurrent dislocation shoulder. The aim of this study was to assess the clinical and radiological corelation in the patients with recurrent dislocation shoulder. Methods: Forty-four patients of recurrent dislocation shoulder who were evaluated between January 2015 and December 2017 at a tertiary care center, clinically and radiologically using CT scan and meeting the inclusion criteria, were included. The correlation between the clinical history of the number of dislocations and the bone loss using CT scan was evaluated. Two sided statistical tests were performed at a significance level of α=0.05. The analysis was conducted using IBM SPSS STATISTICS (version 22.0). Results: All the patients were male with mean age of 25.95 (SD ± 4.2) years were evaluated. Twenty-four patients sustained injury in sporting activities while 20 patients sustained injury in training. There were an average of 4.68 (SD ± 3.1, range 2e15, median 3) episodes of dislocation. Forty-one patients had the glenoid bone loss while 40 had the Hill-Sachs lesions. The mean glenoid width defect was 10.80%(range 0e27%) while the mean Hill-Sachs defect was 14.27 mm (range 0e26.6 mm). The mean area of bone loss of the glenoid surface was 10.81%(range 0e22.4%). The lesions were on track in 34 patients and off track in 10 patients. Conclusions: CT scan of the shoulder joint is an effective method for assessing the amount of bone loss. The number of dislocations are correlated significantly with off-track lesions and the amount of bone loss on the glenoid and Hill-Sachs lesion. The glenoid width bone loss of more than 9.80% or Hill-Sachs defect of more than 14.80 mm are the critical defects after which the frequency of dislocations increases. 展开更多
关键词 SHOULDER joint RECURRENT DISLOCATION HILL-SACHS LESION
Osteomyelitis post acromioclavicular joint reconstruction
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作者 Raymond DK.Yeak Hafiz Daud Nasir M. Nizlan 《中华创伤杂志:英文版》 CAS CSCD 2019年第3期182-186,共5页
Acromioclavicular joint (ACJ) injury is a common shoulder injury. There are various techniques of ACJ reconstruction. Superficial infection after ACJ reconstruction is not an uncommon complication. However, osteomyeli... Acromioclavicular joint (ACJ) injury is a common shoulder injury. There are various techniques of ACJ reconstruction. Superficial infection after ACJ reconstruction is not an uncommon complication. However, osteomyelitis post ACJ reconstruction has never been highlighted as a possible complication. Our patient is a 31-year-old male who sustained a Rockwood 5 ACJ dislocation and had anatomical ACJ reconstruction with autogenous gracilis and semitendinosus graft. Our technique involved the anatomical reconstruction of the ACJ and the coracoclavicular ligament with the usage of two bioscrews and the temporary stabilisation of the ACJ with two k-wires. As in any orthopaedic surgery, infection is often disastrous especially when the surgery involves implants. It can be disastrous with high morbidity to the patient as well as a costly complication to treat. Therefore, we wish to highlight this case as despite its rarity, osteomyelitis can be devastating to the patient and should be prevented if possible. 展开更多
关键词 ACROMIOCLAVICULAR JOINT DISLOCATION ACROMIOCLAVICULAR JOINT reconstruction INFECTION OSTEOMYELITIS COMPLICATION
Co-seismic change in ocean bottom topography:Implication to absolute global mean sea level change
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作者 Jiangcun Zhou Heping Sun +2 位作者 Jianqiao Xu Xiaodong Chen Xiaoming Cui 《大地测量与地球动力学:英文版》 2019年第3期179-186,共8页
Earthquakes perturb both the ocean bottom topography due to displacements of sea floor and the geoid due to mass redistribution, which induces the relative sea level(RSL) change. However, the relative global mean sea ... Earthquakes perturb both the ocean bottom topography due to displacements of sea floor and the geoid due to mass redistribution, which induces the relative sea level(RSL) change. However, the relative global mean sea level(GMSL) change is zero in that sea water mass is conserved. But the absolute GMSL change is not zero because earthquakes displace total ocean mass with respect to the Earth’s center of mass(CM) which remains unchanged after an earthquake. This displacement, i.e. the absolute GMSL change, may be detectable by altimetry since the satellites are orbiting around CM. In this paper, we proposed a method to estimate co-seismic absolute GMSL change caused by earthquakes based on the point dislocation theory for a spherically symmetric, non-rotating, elastic and isotropic(SNREI) Earth.This change can be directly connected to the perturbation of ocean bottom topography. We first computed co-seismic displacements as well as the change in geo-potential and solved the sea level equation to validate the insignificance of the oceans’ feedback, i.e. the loading effect due to RSL change, to co-seismic displacements. The results imply that the loading effect due to RSL change is negligible on displacements while is considerable on geoid. We then computed the absolute GMSL change caused by co-seismic vertical and horizontal displacements by making use of the integrated Green’s function method. The numerical results show that a large earthquake may raise the absolute GMSL by magnitude of sub-millimeter and the recent three large events cause GMSL to rise about one millimeter, in which the contribution from horizontal displacement is non-negligible. 展开更多
关键词 Point DISLOCATION theory SNREI earth Sea level equation ABSOLUTE GMSL Ocean BOTTOM TOPOGRAPHY
Stress dependence of the creep behaviors and mechanisms of a third-genegation Ni-based single crystal superalloy
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作者 Quanzhao Yue Lin Liu +5 位作者 Wenchao Yang Chuang He Dejian Sun Taiwen Huang Jun Zhang Hengzhi Fu 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第5期752-763,共12页
Elevated temperature creep behaviors at 1100℃ over a wide stress regime of 120-174 MPa of a thirdgeneration Ni-based single crystal superalloy were studied. With a reduced stress from 174 to 120 MPa, the creep life i... Elevated temperature creep behaviors at 1100℃ over a wide stress regime of 120-174 MPa of a thirdgeneration Ni-based single crystal superalloy were studied. With a reduced stress from 174 to 120 MPa, the creep life increased by a factor of 10.5, from 87 h to 907 h, presenting a strong stress dependence. A splitting phenomenon of the close-(about 100 nm) and sparse-(above 120 nm) spaced dislocation networks became more obvious with increasing stress. Simultaneously, ao<010> superdislocations with low mobil让ies were frequently observed under a lower stress to pass through γ precipitates by a combined slip and climb of two ao<110> superpartials or pure climb. However, ao<110> superdislocations with higher mobility were widely found under a higher stress, which directly sheared into y precipitates. Based on the calculated critical resolved shear stresses for various creep mechanisms, the favorable creep mechanism was systematically analyzed. Furthermore, combined with the microstructural evolutions during different creep stages, the dominant creep mechanism changed from the dislocation climbing to Orowan looping and precipitates shearing under a stress regime of 137-174MPa, while the dislocation dim bing mechanism was operative throughout the whole creep stage un der a stress of 120 MPa, resulting a superior creep performanee. 展开更多
关键词 NI-BASED single crystal SUPERALLOY CREEP Dislocation network Critical RESOLVED shear STRESS CREEP mechanism
表面爆炸处理后的ZGMn13Cr2钢的冲击磨损性能及硬化机理 预览
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作者 巴奇楠 宋仁伯 +1 位作者 冯一帆 李论 《材料导报》 EI CAS CSCD 北大核心 2019年第10期1712-1716,共5页
对ZGMn13Cr2钢表面进行一次爆炸处理,测量其冲击磨损性能,观察不同硬化层的显微组织,分析其硬化机理。实验结果表明:经爆炸处理后的ZGMn13Cr2钢硬度随硬化深度的增加而降低,耐磨性提高了1.32~1.41倍,磨损形貌以犁沟、剥落坑为主,还有少... 对ZGMn13Cr2钢表面进行一次爆炸处理,测量其冲击磨损性能,观察不同硬化层的显微组织,分析其硬化机理。实验结果表明:经爆炸处理后的ZGMn13Cr2钢硬度随硬化深度的增加而降低,耐磨性提高了1.32~1.41倍,磨损形貌以犁沟、剥落坑为主,还有少量破碎坑;通过对不同硬化深度的实验用钢表面进行显微表征,发现硬化层内产生了大量的形变孪晶,爆炸表面具有高密度位错的畴界,距爆炸表面10mm处有泰勒晶格以及距爆炸表面20mm处出现大量平行的滑移带和滑移带交割,未观察到马氏体组织,仍以基体奥氏体为主,这说明一次爆炸处理的ZGMn13Cr2钢的硬化机理为孪晶硬化和位错硬化的复合机制。 展开更多
关键词 爆炸处理 ZGMn13Cr2钢 硬化机理 形变孪晶 位错 冲击磨损
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快速多重旋转碾压对碳钢表面组织结构及渗硼的影响 预览
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作者 袁兴栋 王泽力 许斌 《表面技术》 EI CAS CSCD 北大核心 2019年第3期112-117,共6页
目的进一步提高碳钢表面低温B-Cr-Re固体渗硼层的质量。方法采用快速多重旋转碾压法(Fast multiple rotation rolling,FMRR)对碳钢表面进行预处理,然后进行低温B-Cr-Re固体共渗研究。利用透射电子显微镜、高分辨透射电子显微镜、扫描电... 目的进一步提高碳钢表面低温B-Cr-Re固体渗硼层的质量。方法采用快速多重旋转碾压法(Fast multiple rotation rolling,FMRR)对碳钢表面进行预处理,然后进行低温B-Cr-Re固体共渗研究。利用透射电子显微镜、高分辨透射电子显微镜、扫描电子显微镜、X射线衍射仪等测量仪器对基体表层组织结构、显微硬度和渗硼层组织结构进行了表征。结果经FMRR处理后,基体表层发生严重塑性变形,沿着垂直于基体表面由表及里的方向,变形程度逐渐变小,总变形层厚度约为30μm,变形方向呈方向一致的流线结构;部分晶粒发生破碎现象,晶粒逐渐细化,出现约为30nm的纳米结构层,同时观察到基体表层存在非晶、孪晶、高密度位错等结构缺陷。经FMRR处理后,只有?-Fe相的X射线衍射峰变宽,但未发现新相产生。结论经FMRR处理后,基体表层显微硬度明显提高,基体表面得到明显强化。FMRR方法提高了基体表面低温B-Cr-Re共渗速度,低温渗硼层的平均厚度约为30μm,约为未处理低温渗硼层厚度的1.7倍,低温渗硼层质量也明显得到改善。 展开更多
关键词 快速多重旋转碾压 渗硼层 表面纳米化 非晶 位错
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晚期囊袋内人工晶状体复合体脱位的研究进展
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作者 韩笑言 樊琪 +1 位作者 卢奕 杨晋 《国际眼科纵览》 2019年第4期284-288,共5页
晚期囊袋内人工晶状体(intraocular lens,IOL)脱位是一种白内障术后少见但具有严重危害性的并发症。近年来随着人工晶状体眼的人群比例日益增加,眼科医生对这一并发症的关注和研究也逐步增多。研究表明,渐进性的悬韧带功能不全和晶状体... 晚期囊袋内人工晶状体(intraocular lens,IOL)脱位是一种白内障术后少见但具有严重危害性的并发症。近年来随着人工晶状体眼的人群比例日益增加,眼科医生对这一并发症的关注和研究也逐步增多。研究表明,渐进性的悬韧带功能不全和晶状体囊袋收缩是其最可能的发病机制,高度近视、外伤和玻璃体切除术后是其发病的三大高危因素,对高危患者合理使用囊袋张力环是预防晚期囊袋内IOL脱位的较佳策略。 展开更多
关键词 人工晶状体 脱位 危险因素 发病机制
全身麻醉后手法复位联合椎弓根螺钉内固定植骨融合术治疗AndersonⅡ型齿突骨折伴寰枢关节旋转性脱位交锁 预览
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作者 胡安文 曹纬 《脊柱外科杂志》 2019年第3期163-167,171共6页
目的 探讨采用全身麻醉后手法复位联合后路寰枢椎椎弓根螺钉内固定植骨融合术治疗伴寰枢关节旋转性脱位交锁的AndersonⅡ型齿突骨折的临床疗效。方法 收集2006年2月—2015年12月收治的13例合并寰枢关节旋转性脱位交锁的AndersonⅡ型齿... 目的 探讨采用全身麻醉后手法复位联合后路寰枢椎椎弓根螺钉内固定植骨融合术治疗伴寰枢关节旋转性脱位交锁的AndersonⅡ型齿突骨折的临床疗效。方法 收集2006年2月—2015年12月收治的13例合并寰枢关节旋转性脱位交锁的AndersonⅡ型齿突骨折患者的临床资料。术前交锁侧颈部旋转活动度为8°±2°,对侧为27°±9°,疼痛视觉模拟量表(VAS)评分为(5.7±1.8)分,美国脊髓损伤协会(ASIA)分级均为E级。患者均接受气管插管全身麻醉后手法复位联合后路寰枢椎椎弓根螺钉内固定植骨融合术治疗。记录手术时间、术中出血量,随访术后有无内固定松动、断裂等并发症发生及植骨融合情况。对所有患者进行影像学评估,比较术前、末次随访时颈椎旋转活动度、VAS评分和ASIA分级。结果 所有患者随访24~28个月,平均25.3个月;手术时间为80~120min,平均105min;术中出血量为100~330mL,平均150mL。末次随访时交锁侧颈部旋转活动度为45°±12°,对侧为56°±10°,两侧活动度与术前相比差异均有统计学意义(P<0.05);术后颈部疼痛症状均获得不同程度改善,VAS评分恢复至(2.2±1.3)分,与术前相比差异有统计学意义(P<0.05);末次随访时ASIA分级仍为E级。所有患者均未出现切口疼痛、感染、不愈合及神经损伤等并发症,末次随访时无内固定松动、断裂等并发症发生,均实现骨性融合,融合时间为2~4个月,平均3.1个月。1例患者复查颈椎CT时发现2枚螺钉位置欠佳,因其无不适而未予处理。结论 全身麻醉后手法复位联合后路寰枢椎椎弓根螺钉内固定植骨融合术治疗伴寰枢关节旋转性脱位交锁的AndersonⅡ型齿突骨折,可使寰枢关节复位,重建寰枢椎稳定。该术式安全、有效,能减轻患者疼痛,较大程度恢复患者颈椎功能。 展开更多
关键词 寰椎 枢椎 寰枢关节 齿突尖 脱位 脊柱骨折 内固定器
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Martensitic Transformation Eflfect on the Dislocation Emission from a Semi-infinite Crack Tip in Nano composites
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作者 Tengwu He Miaolin Feng Xiuhua Chen 《固体力学学报:英文版》 SCIE EI CSCD 2019年第2期160-172,共13页
A theoretical model is established to investigate the effect of martensitic transformation particle on the dislocation emission from a crack tip in ceramic-matrix nanocomposites. Using the model of dislocation-based s... A theoretical model is established to investigate the effect of martensitic transformation particle on the dislocation emission from a crack tip in ceramic-matrix nanocomposites. Using the model of dislocation-based strain nucleus and the Green's function met hod, the expressions of complex potentials and stress fields are derived in closed form. The critical stress intensity factors for the first-lattice dislocation emission and the maximum number of emitted dislocations are well calculated. The effects of important parameters such as the size of transformation particle, the dislocation emission angle and the distance from the crack tip to the transformation particle on dislocation emission are discussed in detail. The results reveal that the transformation particle shows a significant shielding effect on the dislocation emission from the crack tip, and the shielding effect enhances with an increase in the size of transformation particle. On the other hand, the results also imply that the emission of edge dislocations is closely related with the dislocation emission angle, and there exists a probable angle |θ|≈ 74° making the dislocation emission easiest. Besides, the remarkable crack blunting induced by the dislocation emission is quite difficult for small grain size but easy for the growth of crack. 展开更多
关键词 SHIELDING effect Martensitic transformation. DISLOCATION emission Stress INTENSITY factor NANOCOMPOSITE
Understanding formation of Mg-depletion zones in Al-Mg alloys under high pressure torsion
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作者 Jing Xue Shenbao Jin +3 位作者 Xianghai An Xiaozhou Liao Jiehua Li Gang Sha 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第5期858-864,共7页
Redistribution of elements may take place in alloys during severe plastic deformation, which significantly alters the mechanical properties of the alloys. Therefore, comprehensive knowledge about deformationinduced re... Redistribution of elements may take place in alloys during severe plastic deformation, which significantly alters the mechanical properties of the alloys. Therefore, comprehensive knowledge about deformationinduced redistribution of elements has to be established. In the present paper, the distribution of Mg in an Al-Mg alloy processed by high pressure torsion was examined using atom probe tomography(APT).With crystallographic information extracted by APT data analysis, this research reveals that the movement of dislocations plays an important role in the formation of Mg-depletion zones in the deformed microstructure. 展开更多
关键词 High-pressure TORSION ATOM probe TOMOGRAPHY Aluminum alloys GRAIN boundary diffusion DISLOCATION
Rare variants of Bosworth fracture-dislocation: Bosworth fracture-dislocation with medial malleolus adduction type fracture
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作者 Wei Ren Yong-Cheng Hu Ji-Ke Lu 《中华创伤杂志:英文版》 CAS CSCD 2019年第2期120-124,共5页
Bosworth ankle fracture-dislocation is rare, known to be an irreducible type of ankle injury, with a high incidence of complication. We present two cases of even rarer variants of Bosworth ankle fracturedislocation. T... Bosworth ankle fracture-dislocation is rare, known to be an irreducible type of ankle injury, with a high incidence of complication. We present two cases of even rarer variants of Bosworth ankle fracturedislocation. The first case is a type of supination external rotation adduction, and the second case is a type of supination external rotati on adduction. These types have not bee n described before .In both of the cases we failed to achieve close reduction, and therefore proceeded with emergency surgeries, with open reduction and internal fixation. Both of the cases were performed with a postero-lateral approach to reduce the dislocations, and fix the fractures successfully. Unfortunately in one of the cases, acute compartment syndrome developed post-surgically. However, both cases showed good functional outcomes. 展开更多
关键词 FRACTURE dislocation SUPINATION Rotation ANKLE injuries Complications
Geodynamic simulation of the WenChuan Ms8.0 and Lushan Ms7.0 earthquakes
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作者 Li Liao Jiansi Yang Dongning Zhang 《大地测量与地球动力学:英文版》 2019年第1期49-57,共9页
The Lushan Ms7.0 earthquake, occurred on April 20th, 2013, is another strong earthquake that occurred on Longmen Mountain Faults after the Wenchuan Ms8.0 earthquake. In this paper we construct a finite element model d... The Lushan Ms7.0 earthquake, occurred on April 20th, 2013, is another strong earthquake that occurred on Longmen Mountain Faults after the Wenchuan Ms8.0 earthquake. In this paper we construct a finite element model depicting fault frictional mechanism to study the geodynamics of these two strong earthquakes. The locations of the initial rupture points and the dislocation forms of the Wenchuan earthquake and Lushan earthquake are simulated to find out the potential relationship between the two earthquakes. Simulative results show that the elevation, fault geometry, and the different rheological strengths between the Sichuan basin and Tibetan plateau play an important role in the earthquake dynamics. The dynamic simulation shows the initial rupture points are located at Yingxiu county and the rupture process is mainly along the northeast direction for the Wenchuan earthquake. In particular, the different frictional strengths caused by the fluid pressure decrease between the southern and northern segments of Longmenshan faults after the Wenchuan earthquake have affected the initial rupture point and the fault dislocation form of the Lushan earthquake, when considering the thrust of Tibetan plateau to Sichuan basin as the major dynamic source. 展开更多
关键词 FINITE element model INITIAL RUPTURE point DISLOCATION form Numerical simulation
C1-C2 pedicle screw fixation for adolescent with os odontoideum associated atlantoaxial dislocation and a compound reduction technique for irreducible atlantoaxial dislocation
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作者 Jia Liu Ling-Jun Zhu +4 位作者 En-Ze Jiang Xiao-Gang Bao Bo Hu Dong-Yang Niu Guo-Hua Xu 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第10期1253-1256,共4页
To the Editor: Os odontoideum (OO) is a rare congenital anomaly of the second cervical vertebra that is defined as occurring when an independent ossicle is separated from the base of the odontoid process?⑴ In general... To the Editor: Os odontoideum (OO) is a rare congenital anomaly of the second cervical vertebra that is defined as occurring when an independent ossicle is separated from the base of the odontoid process?⑴ In general, it requires surgeries for the patients who suffer from OO-associated atlantoaxial dislocation (AAD), especially for young patients due to their immature bones and the unavoidable tumbles and physical impacts in their daily lives. 展开更多
关键词 ATLANTOAXIAL dislocation COMPOUND REDUCTION TECHNIQUE
后外侧结构重建对后外侧入路全髋关节置换术后早期脱位的影响 预览
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作者 龚保军 窦强兵 +2 位作者 李行星 袁先发 凤晓翔 《骨科》 CAS 2019年第2期101-104,共4页
目的探讨后外侧结构重建对后外侧入路全髋关节置换术(total hip arthroplasty, THA)后早期脱位的影响。方法回顾性分析2015年1月至2018年1月于我院行后外侧入路初次THA的病人120例,根据术中是否修补关节囊及外旋肌群将病人分为两组:观察... 目的探讨后外侧结构重建对后外侧入路全髋关节置换术(total hip arthroplasty, THA)后早期脱位的影响。方法回顾性分析2015年1月至2018年1月于我院行后外侧入路初次THA的病人120例,根据术中是否修补关节囊及外旋肌群将病人分为两组:观察组60例,舌形切开关节囊,术中将关节囊及外旋肌群原位缝合在大转子后方及臀中肌肌腱附着处;对照组60例,切除后关节囊,术中未进行外旋肌群修补重建。术后3个月内发生的脱位定义为早期脱位,比较两种方法对术后早期脱位率的影响。记录并比较两组病人的手术时间、术腔引流量、髋关节Harris评分。结果观察组手术时间为(51.6±9.5)min,对照组为(45.1±7.5)min,对照组手术时间短于观察组,差异有统计学意义(t=2.008,P=0.036)。观察组术腔引流量为(129.6±11.9)ml,对照组为(136.8±12.4)ml,差异无统计学意义(t=1.187,P=0.269)。观察组未发现早期脱位,对照组早期脱位4例(4/60,脱位率为6.667%),观察组术后Harris评分为(86.1±5.0)分,对照组为(85.9±5.5)分,差异无统计学意义(t=1.416,P=0.092)。结论在后外侧入路THA过程中行后外侧结构重建的手术方式早期脱位率低,修补关节囊及外旋肌群对维持髋关节软组织平衡有一定意义。 展开更多
关键词 关节成形术 置换 关节囊 外旋肌群 重建 后脱位
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弥散强化Pt-10Rh合金高温微观组织结构研究 预览
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作者 李凤 杨晓亮 +6 位作者 唐会毅 吴保安 程小利 罗维凡 万伟建 席铭泽 王桂升 《功能材料》 EI CAS CSCD 北大核心 2019年第6期6052-6055,共4页
用金相显微镜、扫描电镜观测普通Pt-10Rh合金和弥散强化Pt-10Rh合金的微观组织结构,结果表明,普通Pt-10Rh合金在高温下晶粒长大趋势明显,且高温持久性低,而弥散强化Pt-10Rh合金中有强化颗粒氧化锆的存在,能减少晶界缺陷,提高晶界结合力... 用金相显微镜、扫描电镜观测普通Pt-10Rh合金和弥散强化Pt-10Rh合金的微观组织结构,结果表明,普通Pt-10Rh合金在高温下晶粒长大趋势明显,且高温持久性低,而弥散强化Pt-10Rh合金中有强化颗粒氧化锆的存在,能减少晶界缺陷,提高晶界结合力,降低晶界的扩散速度,减缓位错攀移,有效阻止晶粒长大和晶界的滑移,从而提高材料的强度和使用寿命。 展开更多
关键词 弥散强化 Pt-10Rh合金 位错 晶界滑移 氧化锆
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3D打印技术个性化手术治疗儿童DDH
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作者 李克伟 戎帅 +4 位作者 滕勇 李浩 刘连涛 甄可培 李锋 《中国矫形外科杂志》 CAS CSCD 北大核心 2019年第5期465-469,共5页
[目的]通过建立一条3D打印辅助外科手术途径,探究3D打印技术在儿童DDH手术中的应用及意义。[方法]选择1例大龄儿童DDH患者,利用逆向工程与3D打印技术制作出1:1大小骨盆及股骨模型,用以制定手术计划并术前模拟手术操作。[结果]术中所见... [目的]通过建立一条3D打印辅助外科手术途径,探究3D打印技术在儿童DDH手术中的应用及意义。[方法]选择1例大龄儿童DDH患者,利用逆向工程与3D打印技术制作出1:1大小骨盆及股骨模型,用以制定手术计划并术前模拟手术操作。[结果]术中所见与术前模型的畸形表现一致,术中截骨矫形有效,手术顺利,无并发症,术后恢复良好。[结论] 3D打印技术能够精确、直观地体现畸形情况,指导制定手术计划,模拟手术操作,增加手术的精确性、安全性。 展开更多
关键词 髋关节 发育不良 脱位 3D打印 逆向工程
4H-SiC外延层中堆垛层错与衬底缺陷的关联性研究 预览
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作者 郭钰 彭同华 +2 位作者 刘春俊 杨占伟 蔡振立 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2019年第7期748-754,共7页
本研究探讨了同质外延生长的4H-SiC晶片表面堆垛层错(SF)的形貌特征和起因。依据表面缺陷检测设备KLA-Tencor CS920的光致发光(PL)通道和形貌通道的特点,将SF分为五类。其中I类SF在PL通道图中显示为梯形,在形貌图中不显示;II类SF在PL通... 本研究探讨了同质外延生长的4H-SiC晶片表面堆垛层错(SF)的形貌特征和起因。依据表面缺陷检测设备KLA-Tencor CS920的光致发光(PL)通道和形貌通道的特点,将SF分为五类。其中I类SF在PL通道图中显示为梯形,在形貌图中不显示;II类SF在PL通道图中显示为三角形,且与I类SF重合,在形貌图中显示为胡萝卜形貌。III-V类SF在PL通道图中均显示为三角形,在形貌图中分别显示为胡萝卜、无对应图像或三角形。研究结果表明,I类SF起源于衬底的基平面位错(BPD)连线,该连线平行于<1100>方向,在生长过程中沿着<112ˉ0>方向移动,形成基平面SF。II类和大部分的III-IV类SF起源于衬底的BPD,其中一个BPD在外延过程中首先转化为刃位错(TED),并在外延过程中延<0001>轴传播,其余BPD或由TED分解形成的不全位错(PDs)在(0001)面内传播形成三角形基平面SF。其余的III-V类SF起源于衬底的TED或其它。II-III类SF在形貌通道中显示为胡萝卜,而IV类SF不显示,主要区别在于外延过程中是否有垂直于(0001)面的棱镜面SF与表面相交。上述研究说明减少衬底的BPD,对减少外延层中的SF尤为重要。 展开更多
关键词 碳化硅 同质外延 位错 堆垛层错
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