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1.
拉曼共焦技术、表面拉曼增强技术以及降低入射激光强度的方法,被运用于SOD、DNA等生物分子拉曼散身实验中,以抑制其荧光背景,改善光谱质量。  相似文献   
2.
利用CARS方法研究超短脉冲激光的脉冲宽度   总被引:1,自引:1,他引:0  
耿纪宏  王润文 《光学学报》1991,11(7):07-611
在理论上提出了利用两光束CARS/CSRS方法测量超短脉冲激光的三阶相关函数。实验上在几种样品中测量了CARS/CSRS的时间特性,得到了泵浦光脉冲,SCDL输出光脉冲以及受激喇曼散射光脉冲的宽度。  相似文献   
3.
用硒与尿素化合,新生的由杂环有机硒所组成的Zs-93硒剂治疗移植性S180肉瘤,有显著的抑瘤作用(P<0.01),其作用表现出一定的剂量效应,以5μg/只小鼠为最适,抑瘤率达60.76%,治疗组小鼠的T细胞、SOD活性均有增强。  相似文献   
4.
应用核磁共振和电子自旋共振技术研究了铜锌超氧化物歧化酶(CuZnSOD)的金属重组酶与水溶液中游离组氨酸(His)的相互作用。发现在水溶液中CuZnSOD的金属重组酶活性中心的金属可与加入的His发生作用而被部分地诱导出来,与His形成络合物。  相似文献   
5.
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterised by selective neuronal death in the brain stem and spinal cord. The cause is unknown, but an increasing amount of evidence has firmly certified that neuroinflammation plays a key role in ALS pathogenesis. Neuroinflammation is a pathological hallmark of several neurodegenerative disorders and has been implicated as driver of disease progression. Here, we describe a treatment study demonstrating the therapeutic potential of a tandem version of the well-known all-d-peptide RD2 (RD2RD2) in a transgenic mouse model of ALS (SOD1*G93A). Mice were treated intraperitoneally for four weeks with RD2RD2 vs. placebo. SOD1*G93A mice were tested longitudinally during treatment in various behavioural and motor coordination tests. Brain and spinal cord samples were investigated immunohistochemically for gliosis and neurodegeneration. RD2RD2 treatment in SOD1*G93A mice resulted not only in a reduction of activated astrocytes and microglia in both the brain stem and lumbar spinal cord, but also in a rescue of neurons in the motor cortex. RD2RD2 treatment was able to slow progression of the disease phenotype, especially the motor deficits, to an extent that during the four weeks treatment duration, no significant progression was observed in any of the motor experiments. Based on the presented results, we conclude that RD2RD2 is a potential therapeutic candidate against ALS.  相似文献   
6.
铜锌超氧化物歧化酶(Cu2Zn2SOD)在汞电极上的吸附研究   总被引:8,自引:0,他引:8  
金属氧化还原蛋白质的电化学行为作为生物电化学领域中一个重要的研究内容,受到了广泛的关注犤1~3犦,生物体系一些重要的反应均与基本电荷运动有关,如生物催化、神经传导、光合作用以及呼吸作用等均涉及到一些重要氧化还原蛋白质的氧化还原过程。利用电化学的基本原理和实验方法,不但能在生命体系和有机组织的整体水平上,更主要是能在分子和细胞水平上研究氧化还原蛋白质体系中的电子转移以及氧化态转化的化学本质和规律。铜锌超氧化物歧化酶(Cu2Zn2SOD)是一个二聚体,由两个等同的亚单位组成,每一个亚单位含有咪唑桥联的铜?和锌?离子,催…  相似文献   
7.
超氧化物歧化酶模型化合物的合成、表征及其SOD活性研究   总被引:4,自引:0,他引:4  
吴辉禄  高忆慈 《化学通报》2003,66(11):770-774
合成了 4种过渡金属硝酸盐与三 (2 苯并咪唑亚甲基 )胺 (ntb)和水杨酸 (Hsal)的新固体配合物 ,经元素分析确定其组成分别为 [M2 (ntb) 2 (Hsal) 2 ](NO3 ) 2 ·H2 O(M =Zn ,Co)、[M2 (ntb) 2 (Hsal) ](NO3 ) 3 ·3H2 O(M =Cu)和 [M(ntb) (Hsal) ](NO3 )·2H2 O(M =Ni) ,进行了摩尔电导率、热重、红外与紫外可见光谱、1HNMR等性质的表征。研究了配合物的模拟SOD活性 ,用IC50 表征配合物的模拟SOD活性的大小。  相似文献   
8.
It was studied the effect of ultrasonic processing (22 kHz) of the aqueous suspension of metakaolin, sodium hydroxide and alumina with a molar ratio 2Al2Si2O7:12NaOH:2Al2O3 on the low-modulus zeolite synthesis processes. To investigate the XRD, SEM, IR, EDS had been used. It was shown that after ultrasonic processing, sodium aluminates are formed, what leads to a change in process of further synthesis. It was found that without ultrasonic processing on the stage of thermal treatment at 650 °C, SOD zeolite (|Na6|[Al6Si6O24]) and sodium aluminosilicate (Na6Al4Si4O17) are synthesized. In the sample after ultrasound during thermal treatment, only sodium aluminosilicates of cubic syngony (Na6Al4Si4O17 and Na8Al4Si4O18) are formed. It was demonstrated that sodium aluminosilicates are precursors for the formation of LTA zeolite (|Na12|[Al12Si12O48]). As a result zeolitization of sodium aluminosilicates after the hydrothermal crystallization in alkaline solution, the sonicated sample contained 97 wt% LTA. Without ultrasonic processing, the product of synthesis contained 50 wt% SOD and 40 wt% LTA.  相似文献   
9.
Three new dinuclear Cu(II) complexes with the formulas [Cu2(pxdmbtacn)Cl4] ( 1 ), [Cu2(pxdmbtacn)Cl0.7(NO3)1.3(OH)2(H2O)1.3]?6H2O ( 2 ) and [Cu2(pxdiprbtacn)Cl4] ( 3 ) together with one previously reported complex, [Cu2(pxbtacn)Cl4] ( 4 ), were obtained from Cu(II) salts with three p‐xylylene‐bridged bis‐tacn ligands bearing pendant alkyl substituents or without pendant group. Complex 2 was structurally characterized as a centrosymmetric dinuclear molecule with each metal center being coordinated to some labile ligands in addition to one tacn ring. Based on the results of mass spectrometry and UV–visible spectroscopy, complexes 1 and 3 are capable of existing in aqueous solution as dinuclear species but 4 can partially form a dimer of the original dinuclear motif. Complexes 1 , 3 and 4 can all effectively cleave supercoiled DNA oxidatively in the presence of hydrogen peroxide. The superoxide dismutase (SOD) activities of 1 and 3 measured under physiological conditions are comparable to that of the native CuZnSOD enzyme but the enzymatic activity of 4 is about three‐ to fourfold lower. Furthermore, complexes 1 , 3 and 4 demonstrate moderate scavenging effect on hydrogen peroxide and their catalase activities are in the decreasing order of 3 > 1 > 4 .  相似文献   
10.
Theoretical studies on the thermodynamic and kinetic properties of the reactions of Ti+ with sulfur transfer reagent SCO via the C═S bond activation pathway have been carried on using DFT/B3LYP method, general statistical thermodynamics, and Eyring transition state theory with Wigner correction. The relevant reactions include reaction 1 4 Ti++1SCO → 4 IM 1 4 TS 1 4 IM 2 4 TiS++ 1 CO, and reaction 2 4Ti++1SCO →4IM1→ CP →2IM22TiS++1CO in which the spin multiplicity changes from the quartet state to the doublet state in the crossing region. It is concluded that the increase of the temperature is favored to the reaction 1 process, since the equilibrium constants (K) rises from 0.566 × 10[P]-9 at 200 K to 0.109 × 100 at 1200 K, and the reaction rate constant (k) from 0.222 × 100 s[P]-1 at 200 K to 0.540 × 10 11 s[P]-1 at 1200 K. Moreover, reaction 1 is endothermic, and non-spontaneous in the way the entropy increases, while reaction 2 is exothermic and spontaneous in the way their entropy decreases. The reaction path 2 is the energetically favorable channel, and its thermodynamic data change not largely with the rise of temperature.  相似文献   
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