Mutation scanning-coupled analysis of haplotypic variability in mitochondrial DNA regions reveals low gene flow between human and porcine Ascaris in endemic regions of China

Haplotypic variation within and among the Ascaris populations representing six provinces in China was investigated. Mitochondrial DNA regions in the cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1) genes were amplified by PCR from total genomic DNA samples (n > 720) from Ascaris individuals from humans and pigs, and subjected to mutation scanning and subsequent selective sequencing. For the cox1, ten different electrophoretic profiles were recorded for human Ascaris, and the same number for pig Ascaris, one of them being common to both host species. For the nad1, 11 different profiles were detected for human Ascaris, and 15 for pig Ascaris. Having defined all haplotypes (20 for pcox1 and 26 for pnad1) by sequencing, their frequencies were estimated in each of the two host species and each of the six provinces. For each mitochondrial region, the frequency of the different haplotypes varied considerably, depending on host species and geographical origin. Analysis of the sequence data (representing all haplotypes for each mitochondrial locus) by F-statistics indicated restricted gene flow between human Ascaris and pig Ascaris, and supported the conclusions from previous molecular epidemiological investigations that pigs are not a significant source of Ascaris infection in humans in endemic regions.     

固相萃取搅拌棒萃取-气相色谱分析海水中的多环芳烃

利用固相萃取搅拌棒（SBSE）萃取海水中的多环芳烃，然后用热解吸脱附-气相色谱分析。研究了萃取时间、添加NaCl浓度对萃取效率的影响。实验结果表明，SBSE方法对16种多环芳烃的萃取回收率分别在33．5％～122．4％之间；对标准样品的检出限为2．74-13．5ng／L；方法RSD为3．8％～13．1％。用此方法测定了大连海岸海水中的多环芳烃含量。     

二氧化碳/环氧丙烷/γ-丁内酯三元共聚物微球降解性的研究

动物体内的体液和肠胃等器官的环境各不相同，这就要求各种不同用途的载药体的降解性能必须满足特定环境的要求。同时，可降解材料在不同的降解介质中通常有着不同的降解表现，这也决定着可降解材料的运用环境。因此，有必要对降解性材料在不同降解介质中的降解性进行专门的研究，由CO2和环氧化物合成的脂肪族聚碳酸酯具有良好的生物降解性能。     

6α-甲基-强的松龙乙酸酯合成的改进方法

6α-甲基强的松龙乙酸酯(6α-Methyl-pre-dnisolone acetate)4是不含氟的甾体皮质激素药物,在国外已广泛用于临床。我们曾报道将6α-甲基-11β,17α-二羟基-黄体酮1以I_2、CaO处理,转变成碘化物后,不需分离就可将碘化物与KOAc进行置换,得6α-甲基-可的唑乙酸酯2。2用DDQ进行脱氢,得产物4的收率仪55%。因而我们改用化合物1作底物,先经节杆菌(Arthrobacter simplex)脱氢可     

Preparation and characterization of nanoaggregates of poly(ethylene oxide)-b-polymethacrylate and poly-L-lysine

Poly(ethylene oxide)-b-polymethacrylate (PEO-b-PMA), one of the double-hydrophilic block copolymers, has proved to the form nanoaggregates with poly-L-lysine (PLS). This was confirmed by turbidimetry, zeta-potential measurements, and dynamic light scattering. The nanoaggregate formation is induced by electrostatic charge neutralization of the PMA block with PLS. The properties of the aggregates are affected by PLS concentration as well PEO-b-PMA concentration. The aggregates have potential applications in biomedical science.     

铬系乙烯齐聚和聚合催化剂

综述了近年来国内外铬系催化剂的最新研究进展。介绍了该类催化剂齐聚和合的性能研究和应用，讨论了该催化剂长期引起争议的活性中心，活性价态，以及反应机理，并同时预测了铬系催化剂在工业和纳米技术方面的发展趋势。     

Preparation and Photocatalytic Characterization of Nanoporous TiO2

Nanoporous TiO2 photocatalysts were prepared by use of controlled drying method with surfactants. The surface area and porous properties are dependent on the chain length of incorporated surfactant cation. The TiO2 materials prepared in the presence of surfactant molecules during the gel formation exhibit much higher photocatalytic activity than that prepared in the absence of surfactants.     

[H2en]2{La2M(SO4)6(H2O)2} (M=Co, Ni): First organically templated 3d-4f mixed metal sulfates

The first organically templated 3d-4f mixed metal sulfates, [H₂en]₂{La₂M(SO₄)₆(H₂O)₂} (M=Co 1, Ni 2) have been synthesized and structurally determined from non-merohedrally twinned crystals. The two compounds are isostructural and their structures feature a three-dimensional anionic network formed by the lanthanum(III) and nickel(II) ions bridged by sulfate anions. The La(III) ions in both compounds are 10-coordinated by four sulfate anions in bidentate chelating fashion, and two sulfate anions in a unidentate fashion. The transition metal(II) ion is octahedrally coordinated by six oxygens from four sulfate anions and two aqua ligands. The doubly protonated enthylenediamine cations are located at the tunnels formed by 8-membered rings (four La and four sulfate anions).     

La1-xCaxCrO3体系复合氧化物的甘氨酸-硝酸盐法合成与表征

采用甘氨酸-硝酸盐法(GNP)合成了La1-xCaxCrO3 (x=0～0.3)体系复合氧化物粉料,对合成产物的粉体结构和性能进行了表征,研究了体系组成及合成方法对材料烧结性能和导电性能的影响.实验结果表明,在La1-xCaxCrO3体系中Ca2 离子的引入促进了材料的烧结,随着Ca2 离子含量的增加,材料的烧结致密度和导电性能明显提高.与常规固相法相比,GNP法合成的粉料颗粒细小均匀(100～200 nm),烧结活性高,其烧结体在1400 ℃以下即可达到较高的烧结致密度和良好的电性能.     

金属载体催化剂的涂层研究

在高温氧化处理不同时间的金属载体箔片上涂覆MgAl2O4/Al2O3过渡涂层,利用TG-DSC,XRD,SEM,BET和超声振动等分析测试技术,对载体和涂层的微观结构与表面特性进行研究.结果表明,在950 ℃下高温氧化5 h,箔片表面生成板状Al2O3晶须,有利于增强涂层与箔片的附着力.在载体表面涂覆一层MgAl2O4/Al2O3过渡涂层,有助于提高活性组分与金属载体的结合力,可以获得高结合强度的涂层结构,促使活性元素高度分散.