数字化成形三维钛网在颅骨缺损修补手术中的应用

目的比较预塑球形钛网和数字化成形三维钛网修补颅骨缺损的临床效果,探讨数字化成形三维钛网在颅骨修补手术中的操作要点及应用价值。方法回顾性分析我院2001年8月至2009年1月155例采用预塑球形钛网行颅骨修补术的患者临床资料,与2009年2月至2013年3月83例采用数字化成形三维钛网行颅骨修补术的患者临床资料进行比较。结果手术时间:预塑钛网组(125±8)min,三维钛网组(98±6)min,预塑钛网组平均手术时间明显长于三维钛网组(P0.05);使用钛钉数量:预塑钛网组(11.8±1.5)个,三维钛网组(8.3±1.2)个,预塑钛网组平均使用钛钉数量明显多于三维钛网组(P0.05);外观满意度:预塑钛网组(7.30±0.21)分,三维钛网组(10.00±0.00)分,预塑钛网组外观满意度明显低于三维钛网组(P0.05);术后并发症:预塑钛网组共19例,发生率12.26%,三维钛网组共3例,发生率3.61%,预塑钛网组术后并发症明显高于三维钛网组(P0.05)。结论采用数字化成形三维钛网修补颅骨缺损具有手术时间短,使用钛钉数量少,外观满意度高,术后并发症少优点,是目前颅骨修补手术的首选材料,应该在临床推广应用。     

Designing the epitope flanking regions for optimal generation of CTL epitopes

The flanking amino acids that surround epitopes are critical for effective antigen processing and maintenance of epitope integrity. In the present study, the frequency and characteristics of each amino acid that flanked the peptides generated from the proteasomal degradation of three different subtypes of HIV-1 Gag-p24 were determined. Synthetic flanking regions were designed based on the highest and the lowest frequencies of amino acid with the ideal characteristics at positions upstream and downstream of the proteasomal cleavage site. Peptides were synthesized that contained known CD8+ CTL-epitopes from HIV-1 Gag, CMV pp65, and vaccinia proteins HRP-2, and C16, flanked by amino acid sequences specifically designed to either generate or inhibit the known CD8+ CTL-epitopes. As predicted, the known CD8+ CTL-epitopes were effectively generated from the peptides with synthetic flanking regions specifically designed to promote epitope generation in a proteasome-dependent manner. The majority of the proteasome-generated epitopes were cleaved immediately after the C-terminal amino acid of the specific CTL-epitope. The synthetic peptide sequences containing known CD8+ CTL-epitopes with the flanking regions that promote epitope generation were effectively processed and presented to epitope specific CD8+ T-cells resulting in the production of IFN-γ. These results highlight the importance of flanking regions in promoting efficient antigen processing and presentation. This concept can have important implications in vaccine design and development strategies.     

脑胶质瘤耐放射细胞亚株的建立方法

目的探索诱导并建立脑胶质瘤耐放射细胞亚株的体外实验方法,为进一步研究胶质瘤放疗抵抗发生的分子生物学机制提供基础。方法以脑胶质瘤U251细胞株为实验对象,通过体外细胞培养,应用60Co射线对脑胶质瘤U251细胞株进行小剂量重复的诱导照射,得到U251耐放射细胞亚株RR-U251。观察RRU251细胞形态的变化;MTT检测其细胞活力,流式细胞仪(FCM)检测其细胞凋亡;集落形成实验检测细胞克隆团形成。结果放射治疗后,RR-U251与U251细胞的相比:细胞增殖活力增强11.5%,迁移能力增强50%,侵袭能力增强87.5%,凋亡率下降69.6%,细胞集落形成率升高88.5%;RR-U251放射敏感性明显下降。结论小剂量重复照射诱导法能较好地建立胶质瘤耐放射细胞亚株RR-U251。     

M-CSF、CA153、HPV联合检测在宫颈癌早期筛查中的临床意义

目的研究巨噬细胞集落刺激因子(M-CSF)、糖类抗原153(CA153)、人乳头瘤病毒(HPV)联合检测在宫颈癌早期筛查中的临床意义。方法以该院2016年3月至2018年10月收治的120例宫颈癌患者作为宫颈癌组,另选取同期于该院体检合格者120例作为健康组以及不典型增生患者120例作为CIN组。比较3组研究对象M-CSF、CA153、HPV水平差异,分析宫颈癌患者的M-CSF、CA153、HPV水平相关性以及单独检测和联合检测的效能差异。结果宫颈癌组患者的M-CSF、CA153、HPV水平均显著高于CIN组和健康组(P<0.05);宫颈癌组患者的M-CSF、CA153、HPV水平与宫颈癌呈正相关,均为宫颈癌的独立危险因素,通过ROC曲线分析,宫颈癌组患者的M-CSF、CA153、HPV联合检测的诊断灵敏度高于单独检测,宫颈癌患者的M-CSF、CA153的诊断界值分别为485.12pg/mL和317.62U/mL。结论M-CSF、CA153、HPV联合检测对宫颈癌早期筛查具有重要意义,在一定程度上可对患者的宫颈癌病变进行早期预测。     

Numerical and Experimental Analysis of Titanium Sheet Forming for Medical Instrument Parts

The paper analyses the forming of the surgical instrument handles made of Grade 2 titanium sheets. Sheet metal forming is a technology ensuring high strength and light weight of products. Replacing stainless steels with titanium further reduces instrument weight and additionally provides the required resistance to corrosive environments typical for surgeries. The low instrument weight is important to prevent fatigue of surgeons and allow them to maintain high operational accuracy during long term surgeries. The numerical analysis of the technological process was performed in order to adapt it to forming tool handles using titanium sheets instead of steel sheets. The numerical calculations were experimentally verified. It was found that, in the case of titanium handles, it is necessary to use a blank holder in the first forming operation to eliminate sheet wrinkling in the flange area. The shape and dimensional accuracy of the drawn part after trimming were high enough and the 4th forming operation became unnecessary. Moreover, the process modification included lubrication using rapeseed oil with the addition of boric acid, which effectively prevents the galling of titanium on the working surfaces of the steel tools and ensures a more uniform distribution of plastic strains in the drawn part.     

The Effects of Geometry Size and Initial Microstructure on Deformation Behavior of Electrically-Assisted Micro-Compression in Ti-6Al-4V Alloy

In this study, electrically-assisted micro-compression (EAMC) tests were conducted for cylindrical specimens of Ti-6Al-4V alloy with four geometric sizes and three initial microstructures. The result showed that the specimen temperature nonlinearly increased with the square of current density. The quasi-static heat equilibrium equation was established to quantify the effects of the scale factor on the Joule heat temperature. Moreover, it was demonstrated that the Joule temperature scale effect had a greater effect on the flow stress than the sample size effect for specimens of different dimensions. It was noted that the 0.5 mm diameter sample displayed abnormal deformation behavior, which was related to surface oxidation leading a brittle surface layer. By comparison of the microstructures, it was found that the α→β phase transformation occured below the β transus temperature, which was attributed to the local Joule heat effect and the scattering of drift electrons during EAMC. Furthermore, the flow curves showed a strong dependence of the strength and ductility on the initial microstructure. The widmannstatten microstructure exhibited higher strength, smaller hardening rate and more easy flow localization compared with basket-weave microstructures, which was attributed to the low β phase content and narrow interlamellar spacing of α lamellae grains in the widmannstatten microstructure.     

基于AHP-CRITIC混合加权法和Box-Behnken设计-响应面法优化羌芩颗粒成型工艺及其物理指纹图谱研究

目的 优化羌芩颗粒的干法制粒成型工艺,并对颗粒进行质量控制。方法 以颗粒成型率、吸湿率（H）、溶化率和休止角（α）的综合评分为指标,采用Box-Behnken设计-响应面法结合AHP-CRITIC混合加权法建立干法制粒关键工艺参数（critical process parameters,CPPs）和关键质量属性（critical quality attributes,CQAs）的数学模型,通过该模型构建干法制粒的设计空间,并进行蒙特卡洛验证。采用单形格子设计对满足制粒工艺的甘露醇、麦芽糊精、糊精进行辅料配比筛选,确定最佳辅料配比并进行验证。采用粉体学评价方法对羌芩颗粒各项物理质量属性指标进行综合表征,建立由松装密度（D_a）、振实密度（D_c）、α、豪斯纳比（IH）、H、含水量（HR）、颗粒间孔隙率（I_e）、卡尔指数（IC）、比表面积（SSA）、粒径＜50 µm百分比（Pf）、分布宽度（span）、分布范围（width）、均匀性（HG）共13个二级物理质量指标构成的颗粒物理指纹图谱,评价不同批次间颗粒质量的一致性。结果 羌芩颗粒干法制粒CPPs的设计空间为送料频率37～45 Hz,滚轮频率8.0～11.8 Hz,滚轮压力40～50 kg/cm²。最佳辅料配比为甘露醇86%,糊精14%。15批样品物理指纹图谱的相似度均大于0.95。结论 优选后的羌芩颗粒干法制粒成型工艺稳定可行,中间体物理性质质量评价科学合理,可为中药新药的开发及工业化放大生产提供参考。     

粒细胞-巨噬细胞集落刺激因子膀胱灌注治疗骨髓移植术后出血性膀胱炎的疗效观察

目的：评估粒细胞-巨噬细胞集落刺激因子(GM-CSF)治疗单倍体骨髓移植术后并发Ⅲ～Ⅳ级出血性膀胱炎的临床效果。方法：对7例出血性膀胱炎患者应用GM-CSF进行膀胱灌注300μg／d，连用5天。结果：7例患者中有6例完全缓解，1例无效，获得完全缓解的中位时间为11．3d(范围5～16d)。结论：膀胱灌注GM-CSF治疗骨髓移植术后出血性膀胱炎有效，未见不良反应发生。     

巨噬细胞集落刺激因子对破骨细胞活性的影响

巨噬细胞集落刺激因子(M-CSF)是目前临床上应用最广泛的细胞因子之一,因其具有独特和良好的升白细胞及干细胞动员作用,得到临床医师的肯定。M-CSF可诱导人破骨细胞形成,刺激其分化、存活,参与成熟破骨细胞对骨的吸收作用;而且可以抑制破骨细胞凋亡,因而可用于治疗骨骼石化症。虽然有关M-CSF对破骨细胞的生长、分化和凋亡的影响已有较广泛的研究,但对其确切的细胞生物学机制并不很清楚,本文综述了近年来该方面的研究进展。