海绵中石油降解微生物的分离筛选及降解特性研究

从大连湾原油污染海域生长的海绵中分离筛选到一株原油降解菌OA58,根据其生长形态、培养特征、16S rRNA序列相似性比对分析和生化指标检测,初步鉴定为脱叶链霉菌（Streptomyces exfoliatus）。同时,考察了该链霉菌对原油的降解效果,OA58能以原油为唯一碳源生长,在人工海水培养基中,14 d内对原油（初始浓度为1 g/L）的平均降解率为83%,是一株具有开发潜力的原油降解放线菌。     

小鼠精原干细胞不同转染方法效率的比较

本研究采用腺病毒感染、慢病毒感染、脂质体转染和电穿孔转化方法将含有绿色荧光蛋白（GFP）的质粒转入经过差异贴壁法初步分离纯化的小鼠精原干细胞(SSCs)中,转染48 h后通过流式细胞仪检测GFP阳性细胞比例比较4种方法在体外转染精原干细胞的效率.结果显示,脂质体转染效率最高仅为8.64%,不能满足对精原干细胞进一步实验的要求;电穿孔法效率最高达到25.27%,但转化后细胞大量死亡;腺病毒转染细胞的效率达到了32.4%;慢病毒转染效率最高,达到74.25%. 因此,慢病毒转染法是体外转染小鼠精原干细胞的有效方法.     

Phylogenetic positions of several amitochondriate protozoa

Several groups of parasitic protozoa, as represented by Giardia, Trichomonas, Entamoeba and Microsporida, were once widely considered to be the most primitive extant eukaryotic group―Archezoa. The main evidence for this is their ‘lacking mitochondria’ and possessing some other primitive features between prokaryotes and eukaryotes, and being basal to all eukaryotes with mitochondria in phylogenies inferred from many molecules. Some authors even proposed that these organisms diverged before the endosymbiotic origin of mitochondria within eukaryotes. This view was once considered to be very significant to the study of origin and evolution of eukaryotic cells (eukaryotes). However, in recent years this has been challenged by accumulating evidence from new studies. Here the sequences of DNA topoisomerase II in G. lamblia, T. vaginalis and E. histolytica were identified first by PCR and sequencing, then combining with the sequence data of the microsporidia Encephalitozoon cunicul and other eukaryotic groups of different evolutionary positions from GenBank, phylogenetic trees were constructed by various methods to investigate the evolutionary positions of these amitochondriate protozoa. Our results showed that since the characteristics of DNA topoisomerase II make it avoid the defect of ‘long-branch attraction’ appearing in the previous phylogenetic analyses, our trees can not only reflect effectively the relationship of different major eukaryotic groups, which is widely accepted, but also reveal phylogenetic positions for these amitochondriate protozoa, which is different from the previous phylogenetic trees. They are not the earliest-branching eukaryotes, but diverged after some mitochondriate organisms such as kinetoplastids and mycetozoan; they are not a united group but occupy different phylogenetic positions. Combining with the recent cytological findings of mitochondria-like organelles in them, we think that though some of them (e.g. diplo-monads, as represented by Giardia) may occupy a very low evolutionary position, generally these organisms are not as extremely primitive as was thought before; they should be poly-phyletic groups diverging after the endosymbiotic origin of mitochondrion to adapt themselves to anaerobic parasitic life.     

饥饿和再投喂对日本黄姑鱼生长及其体生化组成的影响

日本黄姑鱼(Nibea japonica)俗称黑毛,属鲈形目,石首鱼科,黄姑鱼属,分布于中国东海及日本南部海域[1,2].其营养丰富、生长快、病害少、易于养殖,是东海区海水养殖的理想品种.     

大麻染色体行为分析

以大麻不同性别的植株为材料,常规压片法观察细胞染色体行为规律。核型分析结果表明:大麻雌雄株的体细胞染色体数目均为2n=20,核型公式分别为雌株2n=2x=20=18m 2sm,雄株2n=2x=20=18m 2sm(1SAT)。雌株体细胞中有2条X染色体,而雄株只有一条X染色体和一条具有大随体的Y染色体。雌雄株核型均为2A型,为较对称核型。这一结果可为进一步研究大麻性别的分化机制提供细胞遗传学理论依据。     

鹦鹉源Ⅰ型禽副粘病毒F和HN基因序列测定与分析

禽副粘病毒(Avian paramyxovirus,APMV)属于副粘病毒科、副粘病毒亚科、腮腺炎病毒属,现已确定有9个血清型(APMV-1～9)。APMV-1血清型是禽类最重要的致病型,几乎所有禽种均对其敏感。该病毒是一种有囊膜的单股负链RNA病毒,由囊膜、核衣壳和核酸组成;基因组全长约15kb,     

增施磷、钾肥对大花蕙兰炭疽病防治效果的影响

通过施用3种不同氮、磷、钾比例的肥料并结合常规药剂防治,对大花蕙兰黄金小神童炭疽病防治效果进行比较试验。结果表明,增施钾肥的[N：P(P2O5)：K(K2O)=15：15：30]和增施磷肥的[N：P(P2O5)：K(K2O)=15：30：15]防治效果显著,防治效果分别达到76．54％、73．71％,显著高于未增施磷、钾肥的(N：P(P2O5)：K(K2O)=15：15：15]防治效果(47．79％),说明增施磷、钾肥有助于提高对兰花炭疽病的防治效果。     

太原市土壤中汞污染及成因研究

由于在城市的生产和生活等活动中长期排放含Hg的废弃物,致使城市土壤中的Hg含量越来越多,城市土壤的Hg污染越来越重,它所产生的危害已经引起人们的关注。本文通过对太原市不同地点的土壤中Hg含量进行监测,阐明了太原市土壤中Hg元素的含量、分布特征及其形成的原因,从而为太原市土壤Hg污染防治提供参考依据。     

The youngest split in sympatric schizothoracine fish (Cyprinidae) is shaped by ecological adaptations in a Tibetan Plateau glacier lake

Although new empirical evidence shows that sympatric speciation has occurred in some species, there are few indisputable model organisms for this process of speciation. The two subspecies ( Gymnocypris eckloni eckloni and G . e . scoliostomus ) of the schizothoracine Gymnocypris fish species complex from a small glacier lake in the Tibetan Plateau, Lake Sunmcuo, fit several of the key characteristics of the sympatric speciation model. We used combined mitochondrial control region sequences and the cytochrome b gene (1894 bp) to address the phylogenetics and population genetics of 232 specimens of G . e . eckloni and G . e . scoliostomus , as well as all of its closely related sister species. We found that: (i) a total of four old lineages were uncovered in the widespread G . e . eckloni , of which only one was shown to be shared with all G . e . scoliostomus individuals and (ii) the new subspecies ( G . e . scoliostomus ) evolved in Lake Sunmcuo from the ancestral G . e . eckloni population within approximately 0.057 Ma. These two taxa of the species complex are morphologically distinct, and reproductive isolation is further suggested. Ecological disruptive selection based on morphological traits (e.g. mouth cleft characters) and food utilization may be a mechanism of incipient speciation of two sympatric populations within Lake Sunmcuo. This study provides the first genetic evidence for sympatric speciation in the schizothoracine fish.     

E-box元件修饰端粒酶核心启动子序列及体外转录活性分析

人类端粒酶启动子(hTERT启动子)在肿瘤基因治疗中的有效性已经得到了证实. 然而,hTERT启动子有限的肿瘤靶向转录活性困扰着它的临床应用.早期研究已经揭示,核心hTERT启动子上的-34位E-box元件与该启动子的肿瘤靶向转录活性有关.为进一步探索核心hTERT启动子序列3′端富余E-box元件是否能提高启动子的肿瘤靶向转录能力,用化学合成方法在野生型hTERT(WT-hTERT)核心启动子片段(编码蛋白起始子ATG上游-268 bp～-10 bp)的3′端接入3个E-box序列, 构建成修饰型hTERT(Mod-hTERT)启动子. 然后,分别用WT-hTERT和Mod-hTERT启动子去调控增强型绿色荧光蛋白(EGFP)及荧光素酶报告基因在293FT、HepGⅡ、SGC7901、U2OS、以及原代培养人成纤维细胞(PHF)中表达. 结果表明, 在Mod-hTERT启动子的各实验组细胞中,能够在端粒酶阳性的293FT、HepGⅡ及 SGC7901细胞组中观测到EGFP的表达,而在端粒酶阴性的U2OS及PHF细胞组中没有观测到EGFP的表达;在端粒酶阳性的293FT、HepGⅡ和SGC7901细胞株中,Mod-hTERT启动子调控下的荧光素酶活性要高于WT-hTERT启动子组（P＜0.01）; 而在端粒酶阴性的U2OS细胞组中,Mod-hTERT启动子调控下的荧光素酶活性则低于WT-hTERT启动子组（P＜0.01); 在PHF细胞组中,Mod-hTERT启动子组与WT-hTERT启动子组的荧光素酶活性差异不显著(P＞0.05).研究提示,在3′端增加E-box元件可以提高核心hTERT启动子序列的肿瘤靶向转录活性.