三维超声心动图评价基因转染骨髓干细胞移植治疗慢性缺血心肌价值

目的探讨动态三维超声心动图(DTDE)评价基因转染自体骨髓基质干细胞移植治疗慢性缺血心肌的价值.方法在猪冠脉左旋支放置Ameroid环建立慢性心肌缺血模型;4周后分组注射编码血管生长素(ANG)基因的腺病毒转染的自体骨髓基质干细胞(组Ⅰ)、编码ANG基因的腺病毒液(组Ⅱ)、单纯自体骨髓基质干细胞(组Ⅲ)和空腺病毒磷酸盐缓冲液(组Ⅳ、对照组);再4周后行病理学检查.应用脱机DTDE重建和分析技术,观测正常、置环后4周及注射后4周左室形状、容积和收缩功能的变化.结果慢性缺血心肌左室舒张和收缩末期容积(LVEDV、LVESV)增大,射血分数(LVEF)降低(P<0.01).注射后,对照组LVEDV、LVESV较其它各组明显增大(P<0.05),射血分数(LVEF)明显降低(P<0.05),与缺血时无明显差异(P>0.05).组Ⅰ～Ⅲ较慢性缺血时LVEDV和LVESV均缩小(P<0.05),LVEF均增大(P<0.05),各治疗组比较,左室重构现象均不同程度地减轻,组Ⅰ较其它组,左室容积减小及收缩功能改善最为显著.组Ⅱ和Ⅲ间测值比较无统计学差异.结论DTDE对评价基因转染自体骨髓基质干细胞移植治疗慢性缺血性心脏病具有重要价值.     

人体骨髓基质干细胞冷冻干燥的探索性实验

人体骨髓基质干细胞已成为组织工程、细胞移植和基因治疗等领域的重要研究对象,目前对它已有低温保存的研究,而通过冷冻干燥的方法对其进行保存国内外未见报导.实验尝试用冻干的方法来保存骨髓基质干细胞.文中选取海藻糖、PVP、HES等作保护剂,应用差示扫描量热仪(DSC)测量其结晶温度和玻璃化转变温度;随后对加入保护剂的细胞溶液进行冻干实验,并应用流式细胞仪对冻干样品复水后的细胞活性进行了测定,其中30%PVP 20%海藻糖对细胞的保护效果较好,细胞成活率达到16.40%.     

自体骨髓干细胞移植与归元方联用治疗急慢性肝损伤实验研究

研究中药归元方与自体骨髓干细胞移植对急慢性肝损伤的治疗作用.研究方法:用肝脏局部注射乙醇的方法复制急性局限性肝损伤模型,复合因素(CCl4、乙醇、高脂、低蛋白)刺激复制大鼠肝纤维化模型,通过定量组织学、肝功能检查、免疫组化、肝组织羟脯氨酸含量、损伤或纤维区骨髓干细胞观察等综合评价中药、自体骨髓干细胞移植及两者合用的疗效.结果:归元方与自体骨髓干细胞移植可减小肝损伤区域,改善肝功能,使纤维肝组织表达μPA增强,降低血清ALT,AST,PCⅢ,HA和肝组织羟脯氨酸的含量,改善肝组织肝纤维化评分,骨髓干细胞能在肝损伤、肝纤维化形成环境中存活、增殖,并向肝细胞分化,表达肝脏特异的角蛋白CK18.结论:归元方与自体骨髓干细胞移植对急慢性肝损伤有明确的治疗作用,两者合用可优势互补,协同增效.临床上有良好的应用前景.     

四边形单元第三类面积坐标系统

四边形单元面积坐标系统的两种型式(QAC-Ⅰ和QAC-Ⅱ)已被建立.QAC-Ⅰ含四个坐标分量(L1,L2,L3,L4),其中只有两个是独立分量.QAC-Ⅱ只含两个独立的坐标分量(Z1,Z2).这些面积坐标系统为建立对网格畸变不敏感的新型四边形单元提供理论基础.该文系统地建立了具有两个坐标分量(T1,T2)的四边形单元第三类面积坐标系统(QAC-Ⅱ).这个新的QAC-Ⅲ系统不仅保留了QAC-Ⅰ和QAC-Ⅱ的丰要优点,而且具有其他一些优异特性:1)它是自然坐标;2)它与直角坐标系统保持线性关系;3)它只含两个坐标分量;4)由它导出的形函数具有比较简洁的形式;5)它可以直接地推广应用于曲边单元;6)采用三类系统Ⅰ、系统Ⅱ、系统Ⅲ的混合形式常可以导出优化的结果.     

硫杂冠醚为载体的液膜中Ag（Ⅰ）的迁移研究

选择内耦合液膜技术,以CHCl3为膜溶剂,1,4,7,10,13,16-六硫杂-18冠-6(HT18C6)为流动载体,研究Ag(Ⅰ)在(HT18C6-CHCl3)液膜体系中的迁移过程.考察了载体的种类和浓度、料液相浓度、接受相的种类、浓度和pH值、搅拌速度以及温度等因素对Ag(Ⅰ)离子迁移过程的影响.结果表明,在最佳迁移条件下:载体浓度为5.0×10-4mol/L、料液相NaClO4浓度为5.0×10-3 mol/L、接受相Na2S2O3浓度为0.05 mol/L、搅拌速度为120 r/min、工作温度控制在293～313 K范围内,Ag(Ⅰ)的迁移率可达到99%以上.同时Hg(Ⅱ),M(Ⅱ),Ca(Ⅱ),Ni(Ⅱ),K(Ⅰ),Na(Ⅰ),Cr(Ⅲ),Zn(Ⅱ),Cu(Ⅱ),Pb(Ⅱ)和Cd(Ⅱ)等共存金属离子对Ag(Ⅰ)的迁移无影响.对废定影液样品中Ag(Ⅰ)进行迁移富集,银的回收率在99.3%～99.8%.     

纳米微孔杂多化合物Na[Fe2(O2H3)Mo2O8](Ⅰ)和(NH4)[Fe(MoO4)2](Ⅱ)的结构特征

通过采用水热合成法得到了二种具有纳米筛孔的氧簇化合物Na[Fe2(O2H3)Mo2O8](Ⅰ)和(NH4)[Fe(Mo O4)2](Ⅱ).晶体(Ⅰ)属于单斜晶系,空间群为C2/m,晶胞参数为a=9.5450(17),b=6.4381(9),c=0.76405(12)nm;β=116.128(4),Z=2,R1=0.0219,Rw=0.0756.晶体(Ⅱ)属于正交晶系,空间群为Pnma,晶胞参数为a=1.4782(3),b=0.56774(11),c=0.87653(18)nm;Z=4,R1=0.0212,Rw=0.0513.     

纳米微孔杂多化合物Na[Fe2(O2H3)Mo2O8](Ⅰ)和(NH4)[Fe(MoO4)2](Ⅱ)的结构特征

通过采用水热合成法得到了二种具有纳米筛孔的氧簇化合物Na[Fe2(O2H3)Mo2O8](Ⅰ)和(NH4)[Fe(Mo O4)2](Ⅱ).晶体(Ⅰ)属于单斜晶系,空间群为C2/m,晶胞参数为:a=9.5450(17),b=6.4381(9),c=0.76405(12)nm;β=116.128(4),Z=2,R1=0.0219,Rw=0.0756.晶体(Ⅱ)属于正交晶系,空间群为Pnma,晶胞参数为:a=1.4782(3),b=0.56774(11),c=0.87653(18)nm;Z=4,R1=0.0212,Rw=0.0513.     

鳗弧菌灭活疫苗对海水养殖大菱鲆的免疫预防研究

福尔马林灭活的鳗弧菌疫苗分别以浸泡、注射接种的方式对海水养殖大菱鲆鱼苗进行免疫 ,定期检测血清中特异性抗体。 4周后用鳗弧菌悬液 (3.7× 1 0 8cfu/ml) 0 .2ml腹腔注射感染免疫鱼。结果表明 ,灭活鳗弧菌疫苗用 2种方式免疫后都能刺激大菱鲜产生特异性免疫反应。其中注射免疫组在 1周后即可产生特异抗体 ,在 6周内一直呈上升趋势 ,最高达 1 2 2 8.8,免疫 4周后人工感染后的免疫保护力为 91 .70 %。浸泡免疫组在 3周后才产生抗体凝集价 ,凝集抗体效价最高 36 ,免疫保护力为 33.30 %。     

镁合金微弧氧化膜腐蚀电流密度关联过程参量间关系的预计模型

目前,将量钢分析用于镁合金微弧氧化膜腐蚀电流密度关联过程参量预计模型较为罕见.根据镁合金微弧氧化过程参数脉冲频率f、电压U、氧化时间t、电解液浓度ρ和腐蚀电流密度Jcorr之间关联的量,通过量纲分析,构造了“时间因数”、“第一构造体积量”和“第二构造体积量”,分别建立了4参量的预计模型(模型Ⅰ)、2参量的预计模型(模型Ⅱ、模型Ⅲ),利用回归法得到了相应的关联式,并计算了关联式的相对残差.结果表明:3种模型中,当Jcorr较小时,模型Ⅱ的方案较好;当Jcorr较大时,模型Ⅲ的方案较好;所建模型有助于指导材料耐腐蚀性能与制备工艺参数之间关系的试验方案设计.     

经胸三维超声心动图诊断先天性心脏间隔缺损与二维超声心动图诊断的对照研究

目的探讨经胸三维超声心动图(3DTTE)诊断先天性心脏间隔缺损的可靠性和优越性.方法选取彩色经多普勒二维超声心动图(CDE)诊断并接受手术治疗的VSD52例,ASD20例.术前应用HP SONOS 5500型超声心动仪和Tomtec4D Cardio-View RT三维超声成像系统进行3DTTE诊断.结果(1)52例VSD按手术结果分为膜周型35例,双动脉瓣下型17例,与术前3DTTE诊断和CDE诊断完全吻合;VSD手术测值为9.28±3.19mm,与3DTTE测值(8.82±2.92mm)具有良好相关性(r＝0.88,p<0.01);与CDE测值(8.69±3.42mm)也具有良好相关性(r＝0.65,p<0.01).在诊断VSD合并症方面,手术显示合并三尖瓣隔瓣腱索脱入缺损处者4例,3DTTE在术前均做出正确诊断,但CDE漏诊2例,误为两处VSD者1例,误为主动脉瓣下隔膜者1例;手术显示合并主动脉瓣脱垂者4例,3DTTE在术前亦均做出正确诊断,而CDE漏诊2例.(2)20例ASD按手术结果分为继发孔型17例、下腔静脉型2例和上腔静脉型1例,与术前3DTTE诊断吻合,而CDE术前诊断均为继发孔型ASD.20例ASD最大长轴径和最大短轴径的手术测值分别为19.5±4.2mm和14.8±3.7mm.3DTTE估测ASD最大长轴径和最大短轴径分别为18.8±3.7mm和14.0±3.3mm,与手术测值均具有高度相关性(r＝0.93和r＝0.92,p<0.01);CDE估测ASD最大径为18.6±4.1mm,与手术最大长轴径测值也具有良好相关性(r＝0.86,p<0.01).结论3DTTE能较真实地反映小儿VSD和ASD及其周围结构信息,可对CDE诊断做出补充或纠正,对诊断小儿先天性心脏间隔缺损具有重要价值.     

Simulation of dye adsorption by beech sawdust as affected by pH

The effect of pH on the batch kinetics of methylene blue adsorption on beech sawdust was simulated, in order to evaluate sawdust potential use as low cost adsorbent for wastewater dye removal. The zero point of charge pH(pzc) of the sawdust, in order to explain the effect of pH in terms of pH(pzc), was measured by the mass titration and the automatic titration methods. The adsorption capacity, estimated according to Freundlich's model, indicate that increase of the pH enhances the adsorption behaviour of the examined material. The lower adsorption of methylene blue at acidic pH is due to the presence of excess H(+) ions that compete with the dye cation for adsorption sites. As the pH of the system increases, the number of positively charged sites decreases while the number of the negatively charged sites increases. The negatively charged sites favour the adsorption of dye cation due to electrostatic attraction. The increase in initial pH from 8.0 to 11.5 increases the amount of dye adsorbed.     

Treatment of groundwater polluted by arsenic compounds by zero valent iron

Batch experiments were carried out to study the kinetics and efficiency of inorganic arsenic removal by zero valent iron (ZVI) powder, and as well as the effects of pH, anions, and humic material (HM) on this process. Moreover, column experiment was conducted for 31 days to treat arsenate solution of 500 microg As/L using waste iron chippings as filling. Batch experiments showed that both arsenate and arsenite compounds could be removed efficiently from simulated groundwater by ZVI under aerobic and relative anaerobic conditions. Aerobic condition was favorable to arsenic removal especially for arsenate, while arsenite could be removed more rapidly than arsenate in relative anaerobic condition. Oxidation of arsenite to arsenate by iron species in aerobic environment was observed, which is thought to be an important pathway of arsenite removal. In an unsealed system, the removal efficiency of both arsenate and arsenite decreased at higher pH value. In a sealed system, acidic and alkaline condition seemed to be favorable for arsenate and arsenite removal, respectively. Phosphate and low concentration sulfate caused a decrease in arsenate removal, while high concentration sulfate as well as nitrate caused slight increase in arsenate removal. Presence of HM in solution slightly inhibited arsenic removal. Arsenic removal efficiency in column study was influenced by flow rate and work period of the column. More than 98% of arsenate could be removed stably with a hydraulic resident time of 2 h at last, and the effluent meet the drinking water standard.     

应用PCI总线的音频处理系统的设计

讨论了一种关于音频调理的方法，由于该系统对传输要求比较高，所以系统的传输速度和效率都是很重要的性能指标，在系统的性能指标基础上，选定了PCI总线接口的方案，为简化电路，论文采用PLX公司的PCI9054芯片实现PCI接口，用FPGA实现FIFO数据缓存和本地总线控制逻辑，使通过音频处理后的声音信号通过声音编解码器出去。最后编写了该系统的驱动程序以及应用程序，达到了预期效果。     

Evolution of the Microstructure by High Velocity Impacts of Particles by Cold Spray

The cold spray technique is still in its innovation stage. This process is similar to other thermal coating techniques with the additional benefit of lower working temperature than the melting energy of the feedstock material. In this study, a new coating–substrate system is developed by using the 80%Ni–20%Cr feedstock powder sprayed by this technique on a superni 601 superalloy substrate. The coating microstructure depends upon both the substrate and coating material properties, and thus, coating obtained in this study has a unique microstructure. The coating microstructure developed and tested in this study by scanning electron microscopy/energy-dispersive x-ray spectroscopy (SEM/EDX) and X-ray diffraction (XRD) techniques is found to be suitable for boilers and incinerators.     

Study of electromagnetic diffraction by curved strip gratings by use of the C-method

The C-method is one of the most efficient and versatile methods designed for diffraction gratings. Its strength lies in the use of a coordinate system in which the surface of the grating coincides with a coordinate surface. The result is a great simplification in writing the boundary conditions. We exploit this simplification to treat the problem of diffraction from curved strip gratings, and we use the combined boundary conditions method that has been introduced for planar strip gratings and proved to be very efficient.     

Acceleration of particles by laser radiation scattered by a system of conductive spheres

An exchange of energy between a charged particle and an EM wave scattered by a conductive sphere or a system of conductive spheres has been calculated. Fields of the near-wave zone are responsible for energy exchange. A proper distribution of the scatterers leads to a cumulative change of the particle energy. The deflection of particles and radiative losses due to the scattered wave have been evaluated. Although both processes seem unimportant for acceleration of heavy particles (protons), they do restrict the acceleration of electrons, particularly the radiative losses. The system is studied as a model of a laser diffraction grating accelerator.     

由PDMS与PVC共热解聚碳硅烷制备SiC-C纤维

以聚二甲基硅烷(PDMS)与聚氯乙烯(PVC)为原料,经过共热解聚合反应合成了聚碳硅烷(PCS P),并制备出SiC C纤维.利用IR、XRD、XPS等分析方法对先驱体PCS P与SiC C纤维的组成、结构与性能进行了研究.结果表明,在PVC的引入量适当的条件下,通过共热聚将少量的短碳链引入到聚碳硅烷结构中,使SiC-C纤维的电阻率显著降低到10-1～101Ω·cm,并保持了良好的结晶性和耐氧化性.     

Bubble propagation by disks formed by ion-implantation

The investigation of implantation conditions for bubble propagation points to the necessity for a minimum dose (1.5 times 10^{16}ions cm²) and a sufficiently thick profile (0.4 μ). The use of flat profiles gives uniform implanted layers and allows values of the maximum defect concentration far away from the amorphization threshold. Unlike in permalloy circuits, bubble stability and bias field margins do not increase with the drive field. The propagation is not critically dependent upon disk diameter and spacing.