纯化

And Catt in combination with poly-aerylamide gel preparative electrophoresis to isolate serum high density lipoprotein in a pure form was developed.

作者以多聚阴离子—硫酸右旋糖酐沉淀分离，再以聚丙烯酰胺凝胶制备电泳进一步纯化，可获得较纯净的血清高密度脂蛋白。

It is very difficult to extract active RNA from Aspergillus niger because of the existance of complex cell wall and endo-Rnase activity.

由于复杂的细胞壁和内源酶活性的存在，所以要从丝状真菌中提取和纯化出有生物活性的RNA比较困难。

With the development of the tumor stem cell theory, targeted therapy on stem cells has become a new theory. How to separate and purify tumor stem cells has also become an important part of the research.

随着肿瘤干细胞学说的日趋成熟，针对干细胞的靶向治疗已成为新的理论，分离与纯化肿瘤干细胞是研究的重要组成部分。

The synthesis method comprises the following steps: adding 2-( 5-(dimethylamino methyl- 2- furyl methyl sulpho ethylamine and 1- methylthio- 1- methylamino- 2- nitro ethylene with a molar ratio of 1.04: 1 into water, heating to 48- 52 Deg. C, reacting 4.5 hours with a vacuum degree of 0.02- 0.05 MPa, cooling, adding sodium-hydroxide of concentration of 10% to regulate the PH value to 11.0- 11.4, filtrating and cooling the filtrate to 0- 2 Deg. C, crystallizing for 12 hours, centrifugally filtrating, and rinsing filter cake with purity water to prepare wet ranitidine alkali; dissolving ranitidine alkali in alcohol and reacting with chlorhydric acid to prepare ranitidine hydrochloride.

合成方法包括：将摩尔比为1.04∶1的2-(5-(二甲氨基甲基-2-呋喃基甲基硫代乙胺与1-甲硫基-1-甲胺基-2-硝基乙烯加入水中，升温至48-52℃，于真空度0.02～0.05MPa反应4.5小时，反应完毕降温，用10％氢氧化钠溶液调pH＝11.0-11.4，抽滤，滤液降温至0～2℃，结晶12小时，离心甩滤，用纯化水漂洗滤饼，得雷尼替丁碱湿品；将雷尼替丁碱溶于乙醇中与盐酸反应，制备得到盐酸雷尼替丁，产品符合欧洲药典标准。

Among them,CsCl density gradient centrifugation is often used,because product purity is good by this method.

在纯化病毒的方法中，氯化铯密度梯度离心法是较为常用的方法之一，方法简便易行，获得的病毒样品较纯。

When the beers are not easily filtered, they sometimes can be separated by centrifugation, which is the subject of this chapter.

当发酵液不易被过滤纯化时，我们可以采用离心的方法来分离，这也是这章的主题。

METHODS:Human bone marrow mesenchymal stem cells were isolated by combining density gradient centrifugation with plastic adherence .

方法密度梯度离心和贴壁培养相结合，分离纯化人骨髓间充质干细胞。

Objective To study the stability and physico-chemical property of prepared red pigment from Cercis chinensis Bge.

摘 要：目的探讨纯化的紫荆花红色素的稳定性和理化性质。

To study and know well the rudimentary knowledge and the basic techniques of modern Microbiology are demanded for Graduate students. The experiments including the principle and operation of phase contrast microscope and fluorescence microscope; Microphotography , the technique of photographic enlargement;Applications of polymerase chain reaction ; Construction, transformation and detection of plasmid in E.coli ; Infectivity of virus and its molecular detection ; The technique of protoplast fusion in filamentary fungi ; Induction and purification of β-galactosidase from E.coli and assay the enzyme activity; Detection of GC content and DNA-DNA hybridization in bacteria ; Production , extraction and detection of poly--hyduoxy butyrate from bacteria.

以实验教学为主，要求研究生学习和掌握一些现代微生物学研究所需的基本技术，内容包括：相差显微镜、荧光显微镜的使用和显微摄影技术，PCR技术的应用，细菌质粒的构建、转化及检测技术，病毒的侵染性及其分子检测技术，丝状真菌原生质体融合技术，大肠杆菌β-半乳糖苷酶的分离及纯化及其动力学测定技术，细菌G+C mol%的测定及细菌DNA-DNA杂交技术和聚羟基丁酸产生菌的发酵、产物提取及检测技术等。

The expressed product was purified by metal chelate chromatography, identified by Western blot and determined for activity.

表达产物经金属螯合层析柱纯化，并进行Western blot 分析及活性检测。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失