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In this study, first time, we investgated the molecular mechanism of pneumcoccal pathogenity, including virulence formation and resistance to β-lactams, on the point view of transformation. 1. In order to offer methods and pneumococci strains for later study, a transformation model of Streptococcus pneumoniae in laboratory was well established, by inducing pneumococci into transformation with CSP.

研究包括以下四部分内容：1、为后继的研究提供方法学支持和所需菌株，本研究利用CSP诱导细菌转化发生，建立了肺炎链球菌的实验室转化模型；并构建了肺炎链球菌转化缺陷菌株，通过抗生素培养基培养和PCR鉴定菌株构建成功。

Using this model three competence-deficient pneumococci, which was identified by PCR and transformation experiment, were constructed. It is found different strain has different bacterial optimal density for being induced into competence. The optimal density for strains 1, 2 and 22 was 0.1, 0.08and 0.07 respectively. The optimal condition for transformation is c plus y culture at pH8.0. In c plus y culture at pH6.8, which restrained pneumococci forming transformation naturally, pneumococci could be induced to form transformation by CSP.It is concluded that we could induce different S.pneumoniae by CSP into competence in their optimal density in laboratory. 2. It was discussed the relationship between pneumococcal transformation formation and its opportunistic pathogenesis. Comparing their virulence with that of parental strains by challenging mice intraperitoneally and adhering to ECV-304 cell respectively.

结果表明不同肺炎链球菌株的转化最适菌密度不同，1、2和22号菌株的最适转化密度分别为0.1、0.08和0.07；用于转化的CTM培养基最适为pH 8.0的C+Y培养基；在自然转化下不能诱导转化发生的pH 6.8的C+Y培养基中，使用CSP诱导，也能促使细菌发生转化，只是转化效率较低；结论：实验室条件下，不同细菌在一定菌密度时可利用CSP诱导肺炎链球菌成为感受态发生转化。2、为探讨肺炎链球菌转化对毒力表达的影响，本研究分别通过体外粘附人脐静脉血管内皮细胞ECV-304和体内小鼠毒力实验观察1、2和22号肺炎链球菌和其转化缺陷菌株1t、2t和22t毒力的差异。

To analyze effect of diclazuril and maduramycin on 18S rDNA of Eimeria tenella, the 18S rDNA of sporulated oocyst of the E. tenella anti-diclazuril strain, the E. tenellaanti-maduramycin strain and the E. tenella drug-sensitive strain were cloned and sequenced, and were compared by using DNAStar 5.0 and RNADraw 1.1, respectively.

为探讨抗球虫药物地克珠利和马杜拉霉素对柔嫩艾美球虫18S rDNA的影响，分别对人工诱导的柔嫩艾美球虫地克珠利抗药株、马杜拉霉素抗药株和药物敏感株孢子化卵囊的18S rDNA基因进行了克隆测序，并通过生物信息软件进行对比差异分析。

Therefore, we suggest that pollination wasps could be introduced artificially to male syconia of phase B so as to prolong the phase D of male strains; and the match between female and male strains should be 1:2-4, namely, one female strain is cultivated with 2-4 male strains with successive D phases.

因此建议对雄株的B期花序进行人工引蜂的方法修复小蜂种群，从而延长雄性品系D期时长；而雌、雄品系配植模式应为1：2~4，即1个雌株品系与2~4个D期依次衔接的雄株品系配植。

The recombinant viruses, with the gene of reference RV strain VP2, field strain T114 VP6 and T73 G1-serotype VP7, respectively, co-infected Sf9 cell at a multiplicity of infection of 0.5. Harvested the supernatants of culture when the cells were lysed fully (about 7-10 days), or harvested cells before cell lysates (about 4-5 days after infection) and then treated the cells with lysing solution. The supernatants of and cell lysates were ultracentrifuged twice with 40% sucrose cushion at 93 000g, and the sediment products were harvested with TNC buffer. The purified VLPs samples were separated by SDS-PAGE, and then stained by Coomassie blue and silver nitrate and detected by Western blot to analyze the composition of VP2, VP6 and VP7 and their specificity. The morphologic structure of recombinant VLPs was detected by EM.

含标准株VP2、地方株T114 VP6和地方株T73 G1型VP7蛋白编码基因的重组病毒以0.5 MOI共感染Sf9细胞制备2／6／7病毒样颗粒，待细胞完全裂解后收获培养基上清或感染后5天细胞裂解前收获细胞并用裂解液裂解，培养基上清和细胞裂解液样品两次40％蔗糖垫93000g超速离心，沉淀样品经SDS-PAGE胶分离，用考马氏亮兰和硝酸银染色以及Western blot检测样品中VP2、VP6和VP7蛋白的组成以及特异性，电镜检测重组病毒样颗粒的形态结构。

As a wide variation exists among this species, differentiating the harmful and beneficial strains would help in finding ways of controlling the infections by eliminating harmful shrimp pathogenic vibrios.

由于溶藻弧菌种内不同菌株存在较大的差异，区分有害菌株和有益菌株将有助于消除对对虾有害的治病性弧菌而寻找一种控制由溶藻弧菌引起的疾病的方法。

We obtained mutants by the technology of low energy ion and screened out 6 mutant isolates which can effectively control postharvest anthracnose of apple fruits by plate test.

通过平板初筛，筛选出6株对苹果炭疽病菌有较高抑菌作用的菌株，经苹果果实活体侧定从中筛选出对苹果炭疽病有较高拮抗作用的菌株BS 80-6和BS100-6。

An acceptable DNA fingerprint was constructed with 2 primers that could be used to identify these Au-ricularia auricula cultivars, all cultivars were distinguished from each other and showed genetic diversity.

用NTSYS软件进行聚类分析，可将14个供试菌株分为2个类群，类群Ⅰ包括11个菌株，且其可进一步划分为3个亚类；类群Ⅱ包括3个菌株；其中&981&和丰收1号的遗传距离最近。

Probiotics are tested for minimum inhibitory concentrations of 20 kinds of antibiotics by broth dilution method on cation-adjusted Mueller-Hinton broth with lysed horse blood.

采用肉汤稀释法，对中国益生菌保健品行业常用的9株双歧杆菌和22株乳杆菌，共计31株益生菌进行了20种抗生素的耐药性检测。

And all the soil samples were collected from the surroundings of cinnamon oil factory, flower fertilizer and so on. On the whole, this research mainly included two aspects:(1) To screen and ferment the strains producing the aimed enzyme and study on the enzymatic synthesis reaction of natural benzaldehyde.

其研究内容主要包括两个方面：(1)产酶菌种的筛选、发酵以及酶催化合成天然苯甲醛反应的研究通过大量实验，采用常规方法培养时，共筛出1 81株对肉桂醛有耐受性的菌株；将常规培养基换成细菌培养基以后，共筛出36株菌。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。