The protective effects of compound sarcopyramis nepalensis wall on acute hepatic injury in mice

目的观察复方风柜斗草对四氯化碳(CCl4)引起的小鼠急性肝损伤的保护作用。方法将小鼠随机分为空白组、模型组、复方风柜斗草低剂量组(2.2 g/kg)、中剂量组(4.4 g/kg)、高剂量组(8.8 g/kg)和联苯双酯阳性对照组(0.2g/kg)。空白组与模型组给予1%羧甲基纤维素钠(CMC-nA)水溶液,其他组给予相应的药物,1次/d,连续灌胃给药10 d后,除正常组外,腹腔注射CCl4致小鼠急性肝损伤。检测肝组织中的超氧化物歧化酶(SOd)及血清中丙氨酸氨基转移酶(AlT)、天冬氨酸氨基转移酶(AST)的活性,同时检测血清中总胆红素(T-bIl)、直接胆红素(d-bIl)及肝组织中丙二醛(MdA)的水平,并计算肝脏指数。结果预先给予复方风柜斗草能显著降低急性肝损伤小鼠体内T-bIl、d-bIl、AlT、AST和MdA的水平,并升高肝组织中SOd活力。结论复方风柜斗草对CCl4致小鼠急性肝损伤具有保护作用,其机制可能与其所具有的抗脂质过氧化和清除体内过多氧自由基的作用有关。Objective To observe the protective effects of compound sarcopyramis nepalensis wall against tetrachloride( CCl4)-induced acute hepatic injury in mice.Methods The mice were randomly divided into normal group,model group,low dose compound sarcopyramis nepalensis wall group( 2.2 g / kg),medium dose group( 4.4 g / kg),high dose group( 8.8 g / kg),and positive control( biphenyldicarboxylate) groups( 0.2 g / kg).The mice were ig pretreated with compound sarcopyramis nepalensis wall and biphenyldicarboxylate once daily for consecutive 10 d,respectively.The mice in the normal and model groups were given 0.1% CMCNa,the water-solution instead.Then,acute liver injury in mice was induced by ip injection of CCl4.The activities of serum ALT and AST,hepatic SOD,and the level of serum T-BIL and D-BIL,hepatic MDA were also determined,the hepatic indices were calculated.Results The activities of ALT and AST,the level of T-BIL,D-BIL and MDA were significantly decreased by compound sarcopyramis nepalensis wall pretreatment,while activity of SOD in hepatic tissues was markedly increased.Conclusion Compound sarcopyramis nepalensis wall has protective effects against CCl4-induced acute hepatic injury in mice,and the mechanisms might be associated with its anti-oxidative and scavenging free radical activity

Catalytic Properties of Ultrafine SiO_2 Supported Amphiphilic Phosphine-Rh Complex Catalysts

作者简介: 彭庆蓉( 1973- ) , 女, 四川达州市, 讲师, 博士。 通讯联系人：袁友珠[中文文摘]针对均相催化反应后催化剂与产物分离困难和高碳烯烃在水-有机两相中反应速率较低的问题,采用水-有机两亲膦铑络合物负载到超细SiO2载体上催化1-己烯氢甲酰化反应,并与超细SiO2制备负载水相催化剂比较,超细SiO2负载型两亲铑膦络合物催化剂表现出较高的1-己烯氢甲酰化反应活性和选择性,且含水质量分数范围较宽,反应后产物与催化剂容易分离。两亲膦铑络合物超细SiO2负载液相催化剂可避免超细SiO2负载水相催化剂循环使用时水分被提取到有机相的缺点,同时获得较高的氢甲酰化反应活性和选择性。[英文文摘]Because of the lower activity of higher olefins in aqueous/organic biphasic catalysis system and the catalyst separation of homogeneous catalysts,ultrafine SiO2 nanoparticles were used as supports to immobilize amphiphilic phosphine-complex to obtain supported catalysts for hydroformylation of 1-hexene. Compared to the supported aqueous-phase catalysts (SAPC) on ultrafine SiO2 support,the ultrafine SiO2-supported catalyst with amphiphilic phosphine-complex presented a higher hydroformylation performance over a relatively wider range of support hydration. Since the water was distilled to organic phase for more times recycled catalysts, the draw backs of ultrafine SiO2 supported water- soluble phosphine-Rh complexes catalyst could be avoided by using supported liquid- phase catalyst prepared by using amphiphilic phosphine- Rh complexes, obtaining higher activity and selectivity of hydroformylation.国家自然科学基金(20023001

可应用于智能光网络的信令嵌套预留协议分析

文章介绍了一种基于后向预留机制的信令嵌套预留协议（SNRP）。该协议考虑在资源预留过程中,网络通过占用预留过程中的未使用带宽来传送大量非实时数据包。SNRP通过修改后向预留协议来实现。文章还分析了SNRP使用信令机制来提高嵌套预留协议（NRP）性能的措施,SNRP可运用于智能光网络,以增强智能光网络的性能

基于OIF UNI1.0的邻居发现过程的研究

随着自动交换传送网的出现,有必要发展一种可以共同使用的过程,能够在连接到传送网的客户（如IP、ATM和SONET设备）之间请求和建立动态的连接（带有不同的透明度）。用户网络接口（UNI）是用户设备和传送网络之间的服务控制接口。文章详细介绍了O IF UNI1.0邻居发现的过程,并提出用VC++6.0实现邻居发现的方法

采用常规条形流场的质子交换膜燃料电池阴极数值模拟模型建立

对采用常规条形流场的H_2-Air PEMFCs阴极建立了二维数学模型,模型的控制方程耦合了连续性方程、Darcy方程、电传导方程以及O_2和H_2O的对流-扩散方程,对氧的电化学还原反应过程采用Butler-Volmer方程描述.利用模型计算了阴极扩散层中电流密度、O_2和H_2O浓度、催化层界面上局部电流密度的分布,分析了采用常规条形流场时气体在阴极扩散层中的传递机制及各组分浓度分布的特点

高活性的PtRu/C抗CO催化剂

采用共沉积还原法制备了高分散度的催化剂PtRu/C。对此催化剂进行的XRD晶相分析表明，PtRu/C中的双金属形成了合金，并具有较高的分散度。通过EMFC中单电池的伏安曲线和循环伏安法考察了自制PtRu/C催化剂的活性，并与Pt/C和Johnson-Matthey公司PtRu/C进行了比较。由循环伏安中氢的氧化脱附峰的面积和电池纯氢燃料的性能，得到催化剂对H2的活性顺序是：Pt/C>自制的PtRu/C＞Johnson-Matthey PtRu/C，而对H2／（5×10^-5)CO燃料的活性顺序是：自制的PtRu/C>Johnson-Matthey,PtRu/C>Pt/C。通过对循环安中CO氧化过程的研究认为，CO的氧化通过双功能机理（Bifunctional mechanism)进行，Ru的加入提高了催化剂对H2O的活性，使PtRu表面容易形成吸附态的含氧物种（OH）ads，从而降低了催化剂氧化CO的电势

Current Statistical Machine Translation Research in China

2005年7月13日至15日,中国科学院自动化研究所、计算技术研究所和厦门大学计算机系联合举办了我国首届统计机器翻译研讨班。本文主要介绍本次研讨班参加单位的测试系统和实验结果,并给出相应的分析。测试结果表明,我国的统计机器翻译研究起步虽晚,但已有快速进展,参评系统在短期内得到了较好的翻译质量,与往年参加863评测的基于规则方法的系统相比性能虽还有差距,但差距已经不大。从目前国际统计机器翻译研究的现状和发展趋势来看,随着数据资源规模的不断扩大和计算机性能的迅速提高,统计机器翻译还有很大的发展空间。在未来几年内,在基于短语的主流统计翻译方法中融入句法、语义信息,必将成为机器翻译发展的趋势。Institute of Automation,Institute of Computing Technology of Chinese Academy of Sciences,and Department of Computer Science of Xiamen University held the first Statistical Machine Translation Workshop in China together,from July 13th to 15th in 2005.This paper describes the tested systems of involved institutions,and analyzes the results of their experiments.The test results show that although the research of statistical machine translation started late in China,it develops rapidly.The tested systems got quite good results in a short period.Compared with the rule-based systems reported in the formal "863"evaluation,the performance is somewhat lower;however,the difference is small.According to the state of art and the trend of international statistic machine translation research,we believe that there is still great space for the improvement of statistic machine translation,with larger-scale data resources and more powerful hardware.In near future,phrase-based method incorporated with syntax and semantic information will become the mainstream of statistical machine translation.国家自然科学基金资助项目(60272041