Delta大通道与Quadrant通道技术治疗腰椎退行性疾病效果比较

目的 比较Delta大通道与Quadrant通道技术治疗腰椎退行性疾病的临床效果.方法 回顾性分析50例腰椎退行性疾病患者的临床资料,其中采用Delta大通道技术治疗的患者25例(A组),采用Quadrant通道技术治疗的患者25例(B组),比较两组患者的切口长度、手术时间、失血量、卧床时间、住院时间及术前、术后第7天...     

Trappin-2对HaCaT细胞及银屑病跨膜模型增殖的抑制作用

目的 构建Trappin-2的真核表达体系,初步探讨Trappin-2对HaCaT细胞及银屑病跨膜模型增殖的影响.方法 采用DNA重组技术构建Trappin-2的表达载体pIRES2-EGFP-Trappin-2,通过脂质体法转染入宫颈癌HeLa细胞.将Trappin-2高表达上清加入HaCaT细胞及银屑病跨膜模型中,通过3H-TdR掺入法、MTT法、流式细胞术及组化染色Ki67检测对增殖的影响.结果 Trappin-2作用后MTY和cpm值变化率显示Trappin-2可抑制HaCaT细胞的代谢与DNA合成,同时可使HaCaT细胞G2 S期细胞比例下降,而G1期细胞比例增加.Trappin-2可下调银屑病皮损Ki67表达水平.结论 成功将Trappin-2基因转染HeLa细胞,并进行有效表达,初步证实Trappin-2具有抑制HaCaT细胞及银屑病跨膜模型增殖的特性.     

A Novel Model of Ultrasonic Fatigue Test in Pure Bending

The very high cycle fatigue (VHCF) failure of in-service components is mainly caused by the vibration of thin-wall elements at a high frequency. In this work, a novel model of ultrasonic fatigue test was developed to test thin-wall material in bending up to VHCF with an accelerated frequency. The theoretical principle and finite element analysis were introduced for designing a sample that resonated at the frequency of 20 kHz in flexural vibration. In the advantage of the second-order flexural vibration, the gauge section of the sample was in the pure bending condition which prevented the intricate stress condition for thin-wall material as in the root of cantilever or the contact point of three points bending. Moreover, combining the constraint and the loading contact in one small section significantly reduced heating that originated from the friction at an ultrasonic frequency. Both strain gauge and deflection angle methods were applied to verify the controlling of stress amplitude. The fractography observation on Ti6Al4V samples indicated that the characterized fracture obtained from the novel model was the same as that from the conventional bending test.     

镫骨骨质缺损对听力传导影响的有限元分析

目的建立完善的鼓膜-听骨链模型,利用有限元初步探讨镫骨前、后脚骨质缺损对听力传导的影响。方法实验数据源于对一名无中耳病史的成年男性左侧颞骨进行Micro-CT扫描,在医学影像处理软件Mimics上进行三维重建,利用Geomagic形成需要的曲面,最后在SolidWorks上将成型的鼓膜-听骨链模型进行切割组装,建立正常听骨链模型以及镫骨前、后脚骨质缺损模型,利用模型分析骨质缺损对听力传导的影响。结果建立的鼓膜-听骨链模型镫骨足板频振曲线符合相关文献报道,在镫骨前、后脚骨质缺损病理模型下,曲线与正常中耳模型曲线接近。结论利用多软件综合处理,可建立可信度较高的中耳听骨链模型;有限元模拟分析结果显示,镫骨前、后脚缺损部分骨质,未对听力传导产生明显影响。     

隐匿性丙型肝炎病毒感染

隐匿性HCV感染作为一种特殊的感染形式正逐渐受到重视,此文就隐匿性HCV感染的发生机制、生物学特性及临床特征作了简要概括.     

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??OBJECTIVE To study preliminarily the cadmium absorption and accumulation in Ligusticum Wallichii to provide a scientific basis for solving the problem of cadmium excess. METHODS The aboveground and underground parts of Ligusticum Wallichii in different growth periods and the rhizosphere soil were collected from Aoping Town, Pengzhou City and Yongshou Town, Meishan City. The cadmium content was determined, and the enrichment coefficient and transfer coefficient were calculated. RESULTS The average cadmium content in the underground part was 77.21% higher than that in the aboveground part. The cadmium enrichment coefficients and cadmium transfer coefficients of different parts were both greater than 0.5, and the enrichment coefficient of the underground part was 64.75% higher than the aboveground part. CONCLUSION Ligusticum Wallichii has a certain capacity to absorb and transfer cadmium, and most cadmium is enriched in the medicinal roots.     

CA19-9、CA125和CP2在卵巢黏液性肿瘤诊断和监测中的价值

目的探讨血清肿瘤标志物CA19-9、CA125及CP2在卵巢黏液性肿瘤诊断和监测中的价值。方法对北京大学人民医院1999年1月至2007年6月间收治的273例卵巢肿瘤患者的临床资料进行回顾性分析,探讨血清肿瘤标志物CA19-9、CA125及CP2在50例卵巢黏液性肿瘤诊断和监测中的价值,并与223例卵巢非黏液性肿瘤进行比较。结果（1）卵巢黏液性肿瘤中,CA19-9的曲线下面积最大（为0．95）,其次是CA125（为0．90）;而卵巢非黏液肿瘤中,CA125和CP2的曲线下面积最大（均为0．90）。（2）卵巢黏液性肿瘤患者联合检测CA19-9和CA125时,其敏感度（93．8％）较单项检测（CA19-9和CA125分别为75．0％和66．7％）明显提高（P〈0．05）,而特异度（分别为86．1％、86．6％和90．2％）无明显变化（P〉0．05）。卵巢非黏液性肿瘤患者联合检测CA125和CP2时的敏感度（85．0％）,较CP2（70．6％）单项检测明显提高,差异有统计学意义（P〈0．05）;较CA125（80．7％）单项检测虽有提高,但差异无统计学意义（P〉0．05）;3者的特异度（分别为90．2％、88．5％和93．9％）比较,差异无统计学意义（P〉0．05）。（3）82例卵巢恶性肿瘤术前血清肿瘤标志物阳性患者中。可行满意的肿瘤细胞减灭术患者[70％（57／82）]的血清肿瘤标志物于术后2个月内降为正常的百分率高于未能行满意肿瘤细胞减灭术者（分别为75％和28％）,差异有统计学意义（P〈0．05）;且其术后血清肿瘤标志物再次上升的平均时间延长（分别为18．2和16．4个月）,但差异无统计学意义（P〉0．05）;复发率（分别为35％和56％）及死亡率（分别为14％和32％）降低,差异有统计学意义（P〈0．05）。20例术前血清肿瘤标志物阴性患者均可行满意的肿瘤细胞减灭术,其中复发患者仅2例（10％）。（4）卵巢黏液性肿瘤患者术后复发时多为血清CA19-9水平上升,而卵巢非黏液性肿瘤术后复发时主要为血清CA125水平上升,部分患者血清CP2水平也上升。（5）术前血清肿瘤标志物阳性患者较阴性患者生存率明显下降,其中CA125（＋）与CA125（-）、CP2（＋）与CP2（-）患者间生存率比较,差异有统计学意义（P〈0．05）;而CA19-9（＋）与CA19-9（-）患者间生存率比较,差异则无统计学意义（P〉0．05）。结论CA19-9是诊断卵巢黏液性肿瘤的敏感指标,与CA125联合检测可提高对卵巢黏液性肿瘤诊断的敏感度,并对术后监测有重要临床意义。CA125和CP2联合检测则对诊断卵巢非黏液肿瘤更敏感。