Establishment and cryopreservation of liver, heart and muscle cell lines derived from the Chinese alligator （Alligator sinensis）

The Chinese alligator, Alligator sinensis, is a critically endangered species. A conservation project of gene resources for an endangered species first involves the preservation of organs, tissues, gametes, genomic DNA libraries and cell lines. The present study is the first to establish and cryopreserve cell lines of liver, heart and muscle tissues from the Chinese alligator. The study revealed that there was a large discrepancy in cell migration time in primary cultures among liver (11-12 d), heart (13-14 d) and muscle (17-18 d) tissue pieces. The differences in time in primary cell culture suggested that it was relatively easy to build visceral-derived cell lines for reptiles. Biological analysis showed that the population doubling time for thawed cells was approxi- mately 36 h. Karyotyping revealed that the frequency of Chinese alligator cells showing chromosome number as 2n=32 was 88.6%-93.4%. Chinese alligator cell lines established here provide a vital resource for research and are likely to be useful for protection of this rare and critically endangered species. Furthermore, the establishment of these methods may supply technical and theoretical support for preserving genetic resources at the cellular level for other reptile species.     

Experimental study on the explosive boiling in saturated liquid nitrogen

Nowadays,thedevelopmentandapplicationofsuperconductionisbecomingmoreandmoreimpor tantinmanyareas .Duringtheworkingprocessofsu perconductor,somefactors ,forinstance ,deforma tion ,friction ,andmagneticvortex ,canresultinin stantaneousandrandomheatimpulsion ,andmakeitover heatedtothecriticaltemperatureanddeviatefromthenormaloperationcondition .Undersomeex tremeconditions ,thesuperconductorcannotgobacktothenormalstateevenifremovingthetransientheat load ,thusverysevereandunexpectableconse quencema…     

Crystallization and preliminary X-ray diffraction analysis of FKBP12 complexed with a new neurotrophic ligand

Thetherapyofnerveinjuryandneurode generativediseasessuchasAlzheimer’sdiseaseandParkinson’sdiseaseisadifficultprojectforscientiststosurmount.Manydrugsandtherapeuticapproacheshavebeenusedtotreatthesediseases ,buttheresultisunsatisfactory[1] .Inrecent years ,neurotrophinsincludingnervegrowthfactor (NGF) ,neurotrophin3(NT3) ,neurotrophin 4 / 5 (NT4 / 5 )andbrain de rivedneurotrophicfactor (BDNF)werestudiedex tensivelyandfoundtoaffectthesurvival,growth ,and/ordifferentiationofneuronsandsever…     

Hausdorff centered measure of certain linear Cantor sets

Thenotionofpackingmeasure ,introducedinRefs.[1— 3],hasbeenusedincomparisonwithHausdorffmeasuretostudytheregularityandrectifi abilityofsetsintheplane[4 ] .TheHausdorffmeasureisdefinedusingeconomicalcoversofaset,whilethepackingmeasureisdefinedviapackingwithdisjointballscenteredinthegivenset (formoredetailsseeRefs .[5— 7]) .Asasymmetryofthepackingmea sure ,theHausdorffcenteredmeasure ,definedbythecoverswithballscenteredinthegivenset,wasintro ducedinRef .[4 ].RaymondandTricot[8] verifiedthatt…     

He—Ne激光对鸡骨髓培养细胞微核率的影响

不同剂量的Ｈｅ—Ｎｅ激光辐照Ｉｎｓａ鸡骨髓培养细胞，４０ｍＷ×１０′～６０′不能诱导微核产生．培养细胞中吸收亚甲蓝时，同样辐照条件，微核率明显提高，ｔ测验结果Ｐ＜０．０１．     

单圈连通图的边独立指数

依据图的边独立指数概念,探讨了单圈连通图的边独立指数的相关性质,得到了单圈连通图边独立指数的上、下界,并给出了单圈连通图边独立指数达到上、下界的极图     

黑线仓鼠4.5S RNA cDNA的克隆及序列分析

4.5S RNA是一种特异存在于啮齿类细胞中丰富的核小RNA分子（small nuclear RNA,snRNA）.研究以黑线仓鼠（Cricetulus barabensis）为材料,从新鲜肝脏中提取总RNA,以此反转录4.5S RNA cDNA序列,并克隆测序,所得核苷酸序列为88 bp(Genbank登录号:HM1...     

果蝇唾液腺染色体与标本制作技术

本文阐明了果蝇唾液腺染色体的发生机制、形态结构特点及研究意义,提出了玻片标本制作的新技术,为果蝇遗传学的研究提供参考。     

大仓鼠种群生境片断化的遗传效应研究

利用原仓鼠微卫星引物扩增曲阜吴村、平邑柏林和卞桥三个地理种群的大仓鼠基因组DNA，并对长约550bp的特异片段回收测序，利用DAMBE、DNASP4．10及MEGA3．0软件分析所得序列．结果表明，在三个地理种群内及种群间均检测到不同数目的SNPs存在，种群内多态信息含量表现为柏林〉吴村〉卞桥．种群间则以曲阜吴村和平邑卞桥间含量最高．在被检测序列496bp中共检测到6个信息位点，其中4个转换、2个颠换；以平邑柏林和卞桥间含量最低，仅检测到2个信息位点且均为转换．三个地理种群的遗传分化系数（Gst）平均约为0．18，产生的基因流Nm为1．03-1．18，该结果揭示由于生境片断化导致的不同地理种群之间基因流的降低，将会对种群间的遗传分化产生重要的作用．     

Research progress in synthesis and catalysis of polyoxometalates

Polyoxometalates (POMs) form a large class ofmetal oxide cluster type compounds. Their wealthytopology, physical and chemical properties have at tracted increasing interests. In this paper, based onour group’s research, we review the latest progress inthe synthetic chemistry and catalysis of POMs and in troduce some POMs with novel structure and theirderivatives that emerged in 2002—2004. Most of thecited references come from those published in 2003.Due to POMs’superio…