神经死亡抑制剂对全脑缺血模型治疗作用的研究

采用双侧颈总动脉结扎法建立小鼠全脑缺血再灌注模型,用避暗实验、Y型迷宫实验等行为学方法,及神经细胞的HE染色法研究神经死亡抑制剂(简称NDI)对于C57Black/6J小鼠全脑缺血30 min后再灌注大脑海马区的影响。试验表明,与缺血模型组相比,行为学实验中给药组记忆能力增强(p<0.05);免疫染色法实验则为给药组小鼠大脑海马CA1区完整细胞染色数量明显增多(p<0.05)。因此得出,NDI对全脑缺血再灌注模型所引起的神经功能缺损的恢复具有较好的疗效。     

Replication pattern of double minutes derived from an insect cell line

Summary The DNA replication pattern of double minutes derived from an established cell line ofAedes albopictus is described. Although the vast majority of double minutes replicate semiconservatively once during the S phase, some double minutes appear to exhibit different pattern(s). Two theories are suggested as possible explanations of our findings.This work was supported by a grant from the Whitehall Foundation, Inc. awarded to A.B.M.     

液体金属脆机理研究

从实验和计算两个角度研究液体金属脆机理,利用第一原理和陈难先三维晶格反演方法获得Ａｌ－Ｇａ和Ｇａ－Ｇａ有效对势。运用分子动力学研究液态金属吸附对位错发射的影响。模拟结果表明,当Ａｌ晶体的纹表面吸附Ｇａ原子之后,裂尖发射位错临界应力强度因子降低。     

两种染色方法对聚丙烯酰胺凝胶电泳回收蛋白的影响

以牛血清白蛋白(BSA)为材料进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE),分别采用考马斯亮蓝(CBB)G-250染色和咪唑-Zn反染,用电洗脱仪回收.它们的灵敏度分别为500ng和5 ng;蛋白质回收率分别为37.9%和74.4%.     

Transmission electron microscopy and atomic force microscopy characterization of nickel deposition on bacterial cells

Recently bacterial cells have become attractive biological templates for the fabrication of metal nano- structures or nanomaterials due to their inherent small size, various standard geometrical shapes and abundant source. In this paper, nickel-coated bacterial cells (gram-negative bacteria of Escherichia coli) were fabricated via electroless chemical plating. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) characterization results reveal evident morphological difference between bacterial cells before and after deposition with nickel. The bare cells with smooth surface presented transverse outspreading effect at mica surface. Great changes took place in surface roughness for those bacterial cells after metallization. A large number of nickel nanoparticles were observed to be equably distributed at bacterial surface after activation and subsequent metallization. Furthermore, ultra thin section analytic results validated the presence and uniformity of thin nickel coating at bacte- rial surface after metallization.     

Enhancement of the thermal and mechanical properties of polyurethane/ polyvinyl chloride blend by loading single walled carbon nanotubes

Structural, thermal, and mechanical properties of pure blend and nanocomposites based on polyurethane (PU) and polyvinyl chloride (PVC) doped with low different content of single walled-carbon nanotubes (SWCNTs) were studied. The nanocomposites at different concentration were prepared via casting technique. The interaction between PU/PVC and CNTs were examined via FT-IR studies. The changes in the structures of the nanocomposites were examined using X- Ray Diffraction (XRD), and the results indicated that the amorphous domains of nanocomposites increased with increasing SWCNTs content. Transmission electron microscope (TEM) observation indicated that SWCNTs surface was wrapped with the polymer with the thermal properties of nanocomposites improved. The mechanical behavior of the nanocomposites was evaluated as a function of SWCNTs content. The main enhancement in tensile properties was observed, e.g., the tensile strength and elastic modulus increased compared with the pure blend, which may be attributed to the interaction and adhesion between CNTs and the polymer matrices due to the hydrogen bonding between carbonyl groups (C=O) of polymer blend chains and carboxylic acid (COOH) groups of CNTs.     

用电子显微镜研究花岗石的抛光机理

以扫描电子显微镜和透射电子显微镜为主要测试手段,研究了花岗石石材磨削抛光后其表面的微观结构特点,发现了花岗石抛光层的存在,以及抛光层内矿物为晶质的,进而得知花岗石的抛光机理是以热物理作用为主,微切削作用为辅     

一种分析有丝分裂期蛋白的新方法

介绍了一种分析细胞有丝分裂任一时期蛋白质组成及各时期蛋白动态变化的方法，该法将细胞的显微分离，微量蛋白电泳和银染结合起来，通过显微分离可以获得无期它时期细胞污染的任一时期细胞，通过微量蛋白电泳和银染，可以分析其蛋白组成，并通过显微分离100个小麦根尖末期细胞证明了其可行性。     

综合物探方法在煤田水害探测中的应用

在特定的自然、地质环境条件下,具有露头的煤层容易自燃形成火烧区,致使下部矿井与上部水利联系密切,增加了矿井生产的安全隐患。赋存在具有特殊结构的煤系地层中的煤层自燃后产生"热剩磁",可通过高精度磁测对火烧区的范围进行圈定,结合瞬变电磁勘探对火烧区的富水性进行评价,以指导矿井安全生产。本文介绍了两种方法的基本原理、数据采集以及资料处理与解释,结合勘探实例,表明高精度磁测和瞬变电磁联合的方法在煤田火烧区有着良好的应用前景。     

角膜移植的免疫学研究——实验性角膜移植排斥反应的病理组织学观察

角膜移植排斥反应现已成为角膜移植手术失败的主要原因,研究角膜移植免疫反应具有重要意义。本文报告了用同一供体皮肤移植引起兔同种穿透性角膜移植排斥反应的动物模型,描述了角膜移植术后和皮肤移植术后的经过,排斥反应的临床表现,组织学标本,包括光镜、扫描电镜和透射电镜标本的制作方法,重点报告了排斥反应实验组的角膜和对照组透明角膜的组织学观察结果。发现对照组的透明角膜,除了在供、受体组织交界处形成疤痕外,植片和受主角膜表现与正常角膜相同。而在发生排斥反应的角膜,则有大量新生血管侵入,植片有大量的浸润细胞,这些细胞主要是淋巴细胞,还有巨噬细胞、浆细胞、多形核白细胞、成纤维细胞等。植片组织遭到不同程度的损害,受主角膜除了有新生血管生长和有少量浸润细胞附着以外,没有受损。本文讨论了有关动物模型、排斥反应的临床特征、病理组织学与免疫机理及功能的联系,新生血管在排斥反应中起的作用等问题。我们认为本组实验动物模型的临床表现和组织学改变均符合典型的特异性免疫反应。这种反应以细胞免疫为主,亦有体液免疫参与。血管在免疫排斥反应的传入、传出弧中均超重要作用。