顺丁烯二酸酐改性环氧二甲基丙烯酸酯的合成与应用

为了合成顺丁烯二酸酐改性的环氧二甲基丙烯酸酯树脂及其物理机械性能。按量取E51环氧树脂、甲基丙烯酸、顺丁烯二酸酐，与催化剂N，N-二甲基苄胺一起进行反应。检测了由合成EAM单体或EMA单体配制复合树脂的压缩强度、径向拉伸强度、表面硬度、固化深度、吸水值和水溶解值。与EMA单体比较，含EAM单体的复合树脂明显增强了压缩强度、径向拉伸强度、表面硬度、固化深度值，降低了吸水值和水溶解值。     

氨氯地平复方丹参滴丸对高血压大鼠血管壁重塑的干预

目的：探讨氨氯地平片（络活喜）加复方丹参滴丸对自发性高血压大鼠（SHR）血管壁重塑的干预。方法：将32只10周龄雄性SHR随机分成空白对照组（SHRc）、阴性对照组（SHRNs）、阳性对照组（SHRA）和治疗组（SHRA＋D）四组，每组8只。空白对照组未作治疗即测定各指标，并与8只同周龄Wistar鼠比较。除空白对照组外，后三组分别经生理盐水、络活喜、络活喜加复方丹参滴丸治疗8周后处死，测定各项指标。结果：与wistar组比较，空白对照组及阴性对照组血压明显增高、管腔增大、血管壁明显增厚，尤以血管中层平滑肌细胞（VSMC）肥大为主；经治疗后，阳性对照组及治疗组血压明显降低，血管壁增厚得到遏制；阳性对照组与治疗组之间比较，治疗组血管壁变薄更明显，但无统计学意义。结论：络活喜通过降低血压遏制SHR血管壁重塑，加复方丹参滴丸治疗能进一步遏制血管壁重塑，但可能表现为时效关系。     

狼疮方对慢性GVHD狼疮样肾炎小鼠模型的作用

目的探讨狼疮方治疗狼疮肾炎的有效性及作用机理。方法采用慢性移植物抗宿主病(GVHD)狼疮样小鼠模型,经狼疮方、强的松治疗后分别检测血清抗ds-DNA抗体、脾细胞CD40表达及肾脏功能,并观察形态学变化。结果(1)血清抗dsDNA抗体为模型组与正常对照组比较差异有显著性(P＜0．01)；狼疮方组及强的松组与正常对照组比较差异无显著性(P＞0．05)。(2)脾细胞CD40表达的平均荧光强度及阳性细胞百分率模型组均显著高于正常对照组(P＜0．05或P＜0．01)；狼疮方组及强的松组与正常对照组比较差异无显著性。(3)肾脏病理学半定量分析显示各治疗组肾小管间质损伤总积分和肾小球硬化指数均明显低于模型组(P＜0．05或P＜0．01),病变较模型组均显著减轻。结论狼疮方具有一定的免疫抑制作用,可能通过干扰CD40信号,减少自身抗体产生,从而对慢性GVHD狼疮样肾炎小鼠模型具有一定的防治作用。     

火把花根片在小鼠骨髓移植模型中减轻急性移植物抗宿主病的实验研究

目的探讨火把花根片在小鼠骨髓移植模型中减轻急性移植物抗宿主病(acute graft-versus-host disease,aGVHD)的效果及可能的作用机制。方法建立小鼠异基因骨髓移植GVHD模型,预处理为放疗8．0Gy,分为：对照组(n=10)异基因骨髓细胞(2×10~6)加脾T淋巴细胞(2×10~6)移植组；火把花根片组(n=20)异基因骨髓细胞(2×10~6)加脾T淋巴细胞(2×10~6)移植加火把花根片预防组。比较受鼠生存时间和GVHD发生情况,受鼠外周血象中白细胞、血球压积等恢复情况和骨髓细胞中嵌合体H-2D~b阳性细胞百分比以评价造血重建。在移植后不同时间点分别采用流式细胞仪检测受鼠的脾细胞中CD4~+和CD8~+以及CD25和CD69的表达。结果移植后对照组受鼠均于25天内死于GVHD,火把花根片组GVHD的发生率为20%(4/20),与对照组小鼠相比,存活率和时间明显增高和延长(P＜0．01)；存活的火把花根片组小鼠(n=4)40天时骨髓细胞中的H-2D~b阳性细胞百分比达(93．38±4．32)%。移植后10天开始,火把花根片组小鼠CD4~+和CD8~+T细胞比例明显低于对照组(P＜0．...     

新型免疫调节剂—来氟米特

来氟米特是一个新型的免疫调节剂。其作用机制独特 ,血浆蛋白结合率高 ,目前主要用于治疗类风湿关节炎、系统性红斑狼疮、抗移植排斥反应等。本文对来氟米特的作用机制、药动学及临床应用进行综述。     

新型骨替代材料硅磷酸钙的生物相容性实验研究

目的:评价新型骨替代材料硅磷酸钙的生物相容性,从而为其在骨缺损修复领域中的临床应用提供依据。方法:分别选用含10%、5%硅酸钙的硅磷酸钙,分别进行急性毒性试验、肌肉植入试验。结果:含10%与5%硅酸钙的硅磷酸钙无急性全身毒性,对肌肉组织无刺激,植入肌肉后呈降解趋势。结论:新型骨替代材料硅磷酸钙具有良好的生物相容性。     

Multi-Step Forming Simulation and Quality Control of Aluminum Alloy Automobile Rear Upper Control Arm

Aluminum alloy is widely used in automobile parts because of its light weight and good process performance. In view of the complex structure of aluminum alloy automobile rear upper control arms, multiple forming processes and the difficulty in quality control, in this paper, we propose a rolling-forging composite process to produce a rear upper control arm. Based on the reasonable volume distribution of the blank by cross-wedge rolling, multi-step forging was carried out. Finite element simulation of thermomechanically coupled multi-step forming was carried out using DEFORM software. Based on a comparison of the traditional process and the proposed rolling-forging composite forming process, we concluded that the rolling-forging composite process can greatly reduce the material cost and the forming force, resulting in superior product performance. The coarse-grain structure of products at different process temperatures was analyzed by a crystal-phase experiment. The results show that the process temperature of the multi-step process, as well as the heat treatment temperature and time have an important influence on the coarse-grain structure of the product. The optimal preheating temperatures for preforging and final forging dies were determined to be 335 °C and 350 °C, respectively; a preheating temperature of 530 °C and a solution time of 45 min resulted in the least coarse-grain surface structure. The research results provide a theoretical basis for improving the multi-step forming quality of automobile rear upper control arms.     

前交叉韧带重建术后短期内移植体黏性变化

目的 研究前交叉韧带重建(anterior cruciate ligament reconstruction, ACLR)术后短时间内移植体黏性的变化规律。方法 选择6只雄性新西兰兔,以跟腱为移植体制作单侧膝关节ACLR动物模型。ACLR术后15 d将实验兔安乐死,取出移植体、健康的前交叉韧带(anterior cruciate ligament, ACL)和跟腱。测量移植体的截面积,分别进行0.1、1 MPa平衡条件的蠕变实验,并计算黏性系数,总结移植体的黏性变化规律,与健康ACL进行对比。结果 移植体的截面积在手术后15 d内缓慢上升。ACL与移植体的黏性呈非线性变化。在不同应力下,黏性系数有较大差异。移植体黏性系数随ACLR术后时间呈下降趋势,但在低应力下更明显。结论 本文建议,ACLR术后早期康复过程中,应使用助行器,降低步频,并避免踢、踹等对关节冲击的运动。     

Fibrin glue assisted amniotic membrane graft reconstruction of conjunctival fornix and canthus following excision of conjunctival tumours

Conjunctival tumors involving non-limbal locations, such as the fornix and canthus, are typically excised using a “non-touch” technique, often with a wide surgical margin. Reconstruction of these large defects can be difficult due to the contour of the ocular surface and are often complicated by shortening of the fornix, symblepharon formation, and restriction of eye movements. In our experience, the use of amniotic membrane grafts combined with the sealant properties of fibrin glue such as Tisseel® has improved our surgical outcomes during the reconstruction phase. We would like to highlight and describe our surgical technique using fibrin glue and squint hooks to aid amniotic membrane graft reconstruction for surgically challenging locations in the fornix and canthus following excision of conjunctival lesions, with excellent surgical outcomes.     

Early Age Shrinkage and Mechanical Effect of Ultra-High-Performance Concrete Composite Deck: A Case Study with In Situ Test and Numerical Simulation

For the Honghe Bridge project located in Yunnan Province, Southwest China, a steel/ultrahigh-performance concrete (UHPC) composite deck is used in the suspension bridge with a 700 m main span, and the steel stud connectors are used in the 50 mm–thick UHPC layer. To investigate the shrinkage behavior of UHPC and the relevant influence, the in situ time-dependent strain is measured continuously, and within the 20-day curing time, the material behavior is summarized based on test results. This paper proposes a prediction model for UHPC shrinkage which is refined from the widely used B3 model for normal concrete material, and the parameter values are modified and optimized by experimental comparison. Combining the numerical model and the finite element analysis model of the composite deck, the detailed mechanical state in structural parts is studied. For the practical construction, the simulation results indicate that the small thickness of UHPC above the stud and weak bond strength can influence the eventual structural performance greatly. In the discussion of stress distribution at different locations of the deck, the potential crack on the edge and the corner of the UHPC–steel interface and the mechanical damage on the stud connector around are also indicated.