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Cells cannot remain alive outside certain limits o

Cells cannot remain alive outside certain limits o
Cells cannot remain alive outside certain limits o

Cells cannot remain alive outside certain limits of temperature and much narrower limits mark the boundaries of effective functioning. Enzyme systems of mammals and birds are most efficient only within a narrow range around 37C;a departure of a few degrees from this value seriously impairs their functioning. Even though cells can survive wider fluctuations the integrated actions of bodily systems are impaired. Other animals have a wider tolerance for changes of bodily temperature.

For centuries it has been recognized that mammals and birds differ from other animals in the way they regulate body temperature. Ways of characterizing the difference have become more accurate and meaningful over time, but popular terminology still reflects the old division into “warm-blooded”and “cold-blooded”species; warm-blooded included mammals and birds whereas all other creatures were considered cold-blooded. As more species were studied, it became evident that this classification was inadequate. A fence lizard or a desert iguana—each cold-blooded----usually has a body temperature only a degree or two below that of humans and so is not cold. Therefore the next distinction was made between animals that maintain a constant body temperature, called home0therms, and those whose body temperature varies with their environments, called poikilotherms. But this classification also proved inadequate, because among mammals there are many that vary their body temperatures during hibernation. Furthermore, many invertebrates that live in the depths of the ocean never experience change in the depths of the ocean never experience change in the chill of the deep water, and their body temperatures remain constant.

细胞只能在一定的温度范围内存活,而进一步保证它们有效工作的温度范围就更小了。哺乳动物和鸟类的酶系统只能在37℃左右的很小范围内才能有效工作。与此相差仅几度的温度都会大大削弱它们的工作效率。尽管温度变化更大时细胞仍能存活,但机体系统的整体运行能力却被削弱了。其它动物对体温的变化有更强的适应性。

几个世纪以来,人们就认识到哺乳动物和鸟类调节体温的方式与其它动物不同。随着时间的推移,人们对这种差异的描述越来越精确和有意义,但是"暖血动物" 和"冷血动物"这一古老的分类方式至今仍在大众词汇中有所反映。暖血动物包括哺乳动物和鸟类,其它动物统统被视为冷血动物。但是对更多物种进行的研究表明这种分类显然是不适当的。美洲一种小型蜥蜴和沙漠鬣蜥同属冷血动物,但实际上它们的体温通常只比人类的体温低1~2度,因此并不是真正的冷血。因此又出现了恒温动物(即保持恒定体温的动物)和变温动物(即体温随外界环境的变化而改变的动物)这一区分方式。但这种分类也不恰当。因为有不少哺乳动物在冬眠期间会改变体温,而许多生活在深海的无脊椎动物在寒冷的深海水域中体温并不变化,而是恒定的。

Bacteria are extremely small living things. While we measure our own sizes in inches or centimeters, bacterial size is measured in microns. One micron is a thousandth of a millimeter: a pinhead is about a millimeter across. Rod-shaped bacteria are usually from two to four microns long, while rounded ones are generally one micron in diameter. Thus if you enlarged a rounded bacterium a thousand times, it would be just about the size of a pinhead. An adult human magnified by the same amount would be over a mile(1.6 kilometer) tall.

Even with an ordinary microscope, you must look closely to see bacteria. Using a magnification of 100 times, one finds that bacteria are barely visible as tiny rods or dots. One cannot make out anything of their structure. Using special stains, one can see that some bacteria have attached to them wavy-looking “hairs” called flagella. Others have only one flagellum. The flagella rotate, pushing the bacteria through the water. Many bacteria lack flagella and cannot move about by their own power, while others can glide along over surfaces by some little-understood mechanism.

From the bacteria point of view, the world is a very different place from what it is to humans. To a bacterium water is as thick as molasses is to us. Bacteria are so small that they are influenced by the movements of the chemical molecules around them. Bacteria under the microscope, even those with no flagella, often bounce about in the water. This is because they collide with the watery molecules and are pushed this way and that. Molecules move so rapidly that within a tenth of a second the molecules around a bacteria have all been replaced by new ones; even bacteria without flagella are thus constantly exposed to a changing environment.

细菌是极其微小的生物体。我们用英寸或厘米来测量自己的大小,而测量细菌却要用微米。一微米等于千分之一毫米。针头直径大约一毫米。

棒状细菌通常有2~4微米长,而圆形细菌的直径一般只有1微米。因此,即使你把一个圆形细菌放大1000倍,它也不过一个针头那么大。

可是如果把一个成年人放大1000倍,就会变成1英里(或1.6公里)多高。

用一般的显微镜观察细菌时,你必须仔细观察才能看见它们。使用100倍的显微镜时,你会发现细菌不过是隐约可见的小细棒或小点点,而它们的结构你却根本看不出来。使

用特殊的着色剂后,你会发现有的细菌上长着不少波状的"毛发"即鞭毛,而有的细菌只有一根鞭毛。鞭毛的旋转可以推动细菌在水中行进。不少细菌没有鞭毛,因而不能自己行进。还

有些细菌却能通过某些鲜为人知的机制沿物体表面滑动。

我们所熟知的世界在细菌眼中完全是另一个样子。对于细菌来说,水就同糖浆之于人类一样稠密。细菌是如此的微小,周围化学分子的一举一动都会对它们产生影响。在显微镜下,细菌,甚至包括那些没有鞭毛的细菌,经常在水中跳来跳去。这是因为它们与水分子相撞后,被弹向各个方向。分子移动很迅速,仅0.1秒之隔,一个细菌周围的分子就会完全更新。因此,即使是没有鞭毛的细菌也暴露在一个不断变化的环境中。

A folk culture is a small isolated, cohesive, conservative, nearly self-sufficient group that is homogeneous in custom and race with a strong family or clan structure and highly developed rituals. Order is maintained through sanctions based in the religion or family and interpersonal relationships are strong. Tradition is paramount, and change comes infrequently and slowly. There is relatively little division of labor into specialized duties. Rather, each person is expected to perform a great variety of tasks, though duties may differ between the sexes. Most goods are handmade and subsistence economy prevails. Individualism is weakly developed in folk cultures as are social classes. Unaltered folk cultures no longer exist in industrialized countries such as the United States and Canada. Perhaps the nearest modern equivalent in Anglo America is the Amish, a German American farming sect that largely renounces the products and labor saving devices of the industrial age. In Amish areas, horse drawn buggies still serve as a local transportation device and the faithful are not permitted to own automobiles. The Amish’s central religious concept of Demut “humility”, clearly reflects the weakness of individualism and social class so typical of folk cultures and there is a corresponding strength of Amish group identity. Rarely do the Amish marry outside their sect. The religion, a variety of the Mennonite faith, provides the principal mechanism for maintaining order.

By contrast a popular culture is a large heterogeneous group often highly individualistic and a pronounced many specialized professions. Secular institutions of control such as the police and army take the place of religion and family in maintaining order, and a money-based economy prevails. Because of these contrasts, “popular” may be viewed as clearly different from “folk”. The popular is replacing the folk in industrialized countries and in many developing nations. Folk-made objects give way to their popular equivalent, usually because the popular item is more quickly or cheaply produced, is easier or time saving to use or leads more prestige to the owner.

民间文化是小型的、孤立的、紧密的、保守的、近乎自给自足的群体,具有同样的习俗、同样的人种和强有力的家庭或部族结构以及高度发展的宗教仪式。

秩序由宗教或家庭的约束来维持,成员间的关系非常紧密,传统至高无上,很少有变动且变动缓慢。劳动专业分工相对较少。每个人都要做各类活计,尽管男女两性分工不同。绝大多数物品是手工制造的,经济一般为自给自足型。个人主义和社会阶层在民间文化群体中的发展十分薄弱。在象美国和加拿大这样的工业化国家里,一成不变的民间文化群体已不复存在了。在当代美洲的英语区,与民间文化最相似的群体也许算是Amish。Amish是美国的德裔农耕部落,他们基本上拒绝接受工业时代的大多数产品和节省劳力的设施。在Amish 地区,轻便马车仍是当地的交通工具,信徒们不允许拥有汽车。Amish宗教中的核心观念Demut即谦卑典型地反映了在民间文化群中个人主义和阶级的不发达。而与此同时,Amish 对群体的认同性却十分强。Amish人很少和他们宗派以外的人通婚。其宗教,作为Mennonite 信仰的一种,提供了维护秩序的主要机制。相反,大众文化是包含不同种族的大群体,通常高度个性化而且不断在变化。人际关系冷漠,劳动分工明确,由此产生了许多专门的职业。世俗的控制机构,比如警察和军队,取代了宗教和家庭来维持秩序,而且实行的是货币经济。由于存在着这些差异,"大众的"与"民间的"可谓大相径庭。在工业化国家以及许多发展中国家里,大众文化正在取代民间文化。

民间制造的物品正让位于大众化产品,这通常是因为大众化的物品制造起来更快、更便宜,用起来更容易、更方便或者是能给其所有者带来更多的威望。

Human vision like that of other primates has evolved in an arboreal environment. In the dense complex world of a tropical forest, it is more important to see well than to develop an acute sense of smell. In the course of evolution members of the primate line have acquired large eyes while the snout has shrunk to give the eye an unimpeded view. Of mammals only humans and some primates enjoy color vision. The red flag is black to the bull. Horses live in a monochrome world .light visible to human eyes however occupies only a very narrow band in the whole electromagnetic spectrum. Ultraviolet rays are invisible to humans though ants and honeybees are sensitive to them. Humans though ants and honeybees are sensitive to them. Humans have no direct perception of infrared rays unlike the rattlesnake which has receptors tuned into wavelengths longer than 0.7 micron. The world would look eerily different if human eyes were sensitive to infrared radiation. Then instead of the darkness of night, we would be able to move easily in a strange shadowless world where objects glowed with varying degrees of intensity. But human eyes excel in other ways. They are in fact remarkably discerning in color gradation. The color sensitivity of normal human vision is rarely surpassed even by sophisticated technical devices.

人类的视觉,和其它灵长目动物的一样,是在丛林环境中进化出来的。在稠密、复杂的热带丛林里,好的视觉比灵敏的嗅觉更加重要。在进化过程中,灵长目动物的眼睛变大,同时鼻子变小以使视野不受阻碍。在哺乳类动物中,只有人和一些灵长目动物能够分辨颜色。红旗在公牛看来是黑色的,马则生活在一个单色的世界里。然而,人眼可见的光在整个光

谱中只占一个非常狭窄的频段。人是看不到紫外线的,尽管蚂蚁和蜜蜂可以感觉到。与响尾蛇不同,人也不能直接感受到红外线。响尾蛇的感觉器可以感受波长超过0.7微米的光线。如果人能感受到红外线的话,这世界看上去将十分不同,而且恐怖。到那时,将与夜的黑暗相反,我们能轻易地在一个奇异的没有阴影的世界里走动。任何物体都强弱不等地闪着光。然而,人眼在其它方面有优越之处。事实上,人眼对颜色梯度具有非凡的分辨能力。普通人类的视觉感受色彩的灵敏程度,甚至连精密的技术装备都很难超越。

remain的用法

remain[ri'mein] v. 剩余, 逗留, 留下, 依然, 保持v. We must learn to conserve what remains. v. 我们必须学会保存那些剩余的资源。 v. 剩余 v. We must learn to conserve what remains. v. 我们必须学会保存那些剩余的资源。 v. 逗留 v. I didn't remain long in the city. v. 我没在那个城市逗留很长时间。 v. 留下 v. Though the sore being healed, yet a scar may remain. v. 伤口虽然痊愈, 却可能留下伤疤。 v. 依然 v. The present international situation remains tense and turbulent. v. 当前的国际局势依然紧张动荡。 v. 保持 v. Most of the unearthed relics remain intact. v. 大多数出土文物仍保持完好无损。 n. 剩余物, 遗迹, 残骸 n. 剩余物 n. After maintenance the main remains and remainders are left on the domain. n. 维修之后,主要遗骸和剩余物留在了领地上。 n. 遗迹 n. They have found prehistoric remains. n. 他们发现了史前遗迹。 n. 残骸 n. The remains of the wooden hull are fragile and need special handling. n. 木船体的残骸是很不牢固的,搬动时需要特别小心。 【词源解说】 14世纪晚期进入英语,直接源自古法语的remain;最初源自拉丁语的remanere: re(回)+manere(放,置),意为保留。【词形变化】动词过去式: remained 动词过去分词: remained 动词现在分词: remaining 动词第三人称单数: remains 【词义辨析】 remain, linger, stay 这些动词均有“停留,逗留”之意。 remain: 指某人或某物仍留在原处或保持原来的状态。 linger: 着重因愉快的事而使人不愿离开。 stay: 普通用词,多指人在某地暂时逗留。有时可指较长时间的居留。 【语法用法】 1.remain解释为“保持”,“依然”时,后常接表语。 He remained faithful to his wife all his life.

植物食品通过分散SPE进行乙腈提纯隔离和移除之后使用GC-MS和或LC-MSMS 测定杀虫剂残留物QuEChERS方法

植物食品通过分散SPE进行乙腈提纯/隔离和移除之后使用GC-MS和/或LC-MS/MS 测定杀虫剂残留物QuEChERS方法 1 范围 本欧洲标准描述了植物性食物中的农药残留分析方法,如水果(包括干果制品),蔬菜,谷物及其加工品。该方法是在大量的物品/农药组合的基础上研究的。 2原理 用乙腈提取质地均匀的样品。在初始提取之前,含水量低的样品(<80%)需要另外加约10g水。添加硫酸镁、氯化钠和柠檬酸盐缓冲物,强烈振荡将混合物并用离心机进行相分离。等分试样的有机相是经采用批量吸附剂的分散固相(d-spe)提取掉,以及硫酸镁去除残余的水。随着加入少量的甲酸酸化,清理氨基吸附剂提取物(如二级阿明吸附,PSA),提高碱敏感性农药的储存稳定性。最后的提取物可直接用于GC和LC的定性分析。定量通常是使用内标,即乙腈初次加入后添加到提取物中。这个方法的简单概述是附件C所示的流程图。 3 试剂 3.1 一般和安全方面 除非另有规定,使用认可的分析纯试剂。采取一切预防措施,以避免可能被水,溶剂,吸附剂,无机盐等污染。 免责声明—本标准涉及几个市售的产品和适合该方法流程的仪器。此信息是为了方便本欧洲标准的使用者,和被产品命名的欧洲标准委员会不被构成背书。如果他们可以导致相同的结果,等效的产品可能被使用。 3.2 水,HPLC级 3.3 乙腈,HPLC级 3.4 甲醇,HPLC级 3.5 甲酸铵 3.6 无水硫酸镁,砂砾,例如Fluka 63135号 在马弗炉中加热到550 ℃,邻苯二甲酸盐可以被去除(如过夜)。 3.7 无水硫酸镁,细粉 在马弗炉中加热到550 ℃,邻苯二甲酸盐可以被去除(如过夜)。 3.8 氯化钠 3.9 柠檬酸二钠盐1.5水合物 3.10柠檬酸钠 3.11氢氧化钠溶液,物质的量浓度C = 5mol/l 溶解2g氢氧化钠于5ml水中,并稀释至10ml。 3.12缓冲盐混合溶液第二次提取和分配: 称取4 g±0.2无水硫酸镁(3.6),1 g±0.05g氯化钠,1g±0.05 g柠檬酸钠和0,5g±0.03g柠檬酸二钠盐1.5水合物于烧杯中(4.11)。这些量是约10毫升的水样品中的。 高酸性样品(pH<3),在添加缓冲盐后pH值通常是低于5。为了更好地保护酸不稳定化合物,可以通过添加5 mol/l 氢氧化钠溶液(3.11)升高pH值:对于柠檬、酸橙和醋栗,可直接向盐混合物添加600μl氢氧化钠溶液,对于木莓则是200μl。 注意最好是提前准备足够数量的缓冲盐混合物,以便提取可以迅速地进行而不中断。盐混合物的制备可以极大地便利分样器的使用(4.12)。上述的盐的量是用于约含10g水的样品部分。 3.13乙腈-甲酸混合溶液,体积比例φ= 5ml甲酸/100ml

Remain的用法

Remain的用法 一、用作联系动词,指某人或某事物仍保持某种状态,意为“仍然;依旧”,“留;呆;住;待”,后面可接名词、代词、形容词、介词短语、分词作表语。 →1. 接名词作表语 Peter became a manager, but Jack remained a worker. 彼得成为了一个经理,而杰克仍然是个工人。 It remained a secret. 这仍然是个秘密。 →2. 接形容词作表语 Whatever achievements you’ve made, you should remain modest. 无论你取得多么大的成就,你都该保持谦虚。 →3. 接介词短语作表语 He had to remain in hospital until he was better. 他不得不一直住院直到身体好些。→4. 接分词作表语 接过去分词作表语,表示主语所处的状态或已经发生的被动动作;现在分词作表语,表示正在进行的主动动作。 The guests came in, but she remained sitting at the desk reading.客人们都来了,但她还坐在写字台旁读书。 As before, he remained unmoved. 他和以往一样无动于衷。 二、用作不及物动词,意思是“剩下;剩余;遗留”,★★此时不能用进行时态,也没有被动语态★★ After the fire, very little remained of his house. 火灾过后,他的家所剩无几。 After the earthquake, very little remained of the city of Tangshan. 地震过后,唐山这座城市所剩无几。 三、指某事“尚待、有待于以后被处置”,后面常接不定式的被动形式,表示主语是不定式的承受者。 Many problems remain to be solved. 有好多问题尚待解决。 It remains to be seen whether you are right. 你是否正确,以后见分晓。 四、remain作名词 remain作名词时表示“剩余物”,一般用其复数形式。例如: The archeologists found some remains of the Song Dynasty.考古学家发现了一些宋代遗迹。 五、remaining的用法 remaining是形容词,意为“剩余的”,常作前置定语;而left则只能作后置定语。例如:There are still some apples left. 还剩余一些苹果。 I bought a gift for her with the remaining money. 我用剩余的钱给她买了一件礼物。

Vero 细胞 HCP(宿主残留蛋白)ELISA试剂盒说明书

Vero 细胞HCP(宿主细胞蛋白) Vero细胞宿主蛋白酶联免疫检测 目录#F500 预期用途 该试剂盒用于检测用Vero 细胞.生产的制品中是否有宿主蛋白残留。仅供研究和工业生产,不能用于人和动物的诊断。 总结与说明 病毒疫苗或其他治疗用蛋白在Vero细胞中表达使商业用大量生产药物原料产品的经济简便方法。生产和纯化这些产品的过程中会残留Vero细胞中的一些蛋白质(称为宿主细胞蛋白,HCPs)而造成污染。这种污染可以减少药物的疗效,引发毒副反应和免疫学反应,因此最好在实际生产制品过程中将HCPs降低到最低水平。 一些利用抗体来除HCPs的免疫学方法,如Western Blot 和ELISA被广泛使用。虽然Western blot是一种检测HCPs的有效方法,但它受到了一些限制。因为它过程复杂且技术依赖性强,需要操作者对结果进行分析解释。而且,它在本质上是一种定性检测,不能定量分析。Western blot的敏感性易受被检测样品量的影响,也受目的产品浓度的干扰。因此Western blot可用来检测纯化上游的蛋白质,而对纯化下游或终产品的检测灵敏度与特异性较低。本试剂盒中用到的ELISA方法克服了Western Blot的缺点,将敏感度提高了100倍。 ELISA操作简单、客观、可获得半定量的结果,是纯化工艺,过程控制,常规质量检测的最佳选择。这个试剂盒可与纯化过程中残留的可独立污染产品的所有HCPs反应,就这个意义上来说,这个试剂盒是通用的。用Vero细胞轻度裂解物获得抗体并经亲和纯化,得到的最终抗体可以与用于生产各种病毒疫苗和蛋白质产品的四种商用细胞系反应。这一分析表明,绝大多数HCP存在于各种Vero细胞系和纯化过程中。如果你需要一个更为敏感和特异性的方法去检测样品中的HCP量,Cygnus Technologies公司为你推荐一个优于2D Western blot的方法,我们将这个方法称为2D HPLC-ELISA。2D HPLC-ELISA相较于2D Western blot 来说敏感性强,特异性高。要想更多了解此方法,请联系我们公司服务部门。

remain的用法

remain后面接被动语态的动词不定式,表示“尚待”、“留待”remain的用法: 一、作不及物动词用 1.表示“剩下”、“仍有”,只能用于主动语态,不可直接跟宾语,eg.①、They had all those that remained.他们把剩下的全部拿走了。 ②、This visit willalways remain in my memory.这次拜访将永远留在我的记忆之中。 2.表示“留下”、“逗留”,特指在他人走后留下eg.①、They went,but I remained.他们走了,但我留了下来。 ②、I shall remain here all the winter.整个冬天我将留在这里。 3.表示“尚待”、“留待”,后面接被动语态的动词不定式eg.①One problem remains to be solved.有一个问题尚待解决。 ②That remains to be proved.那尚待证实。 二、作系动词用表示“一直保持”、“仍然(处于某种状态)”、“继续存在”、“依然” 1.后面接名词作表语eg.①、Language was,is and will remain the chief means of exchange of ideas.语言,过去、现在和将来依然是交流思想的主要工具。 ②、In spite of their quarrel,they remained the best friends.他们尽管吵过架,却仍不失为最好的朋友。 2.后面接形容词作表语eg.①.We must always rema in modest and prudent.我们必须经常保持谦虚、谨慎。 ②.Despite the danger,she re- mained calm.尽管危险,可她依然镇定自若。

疫苗生产用细胞基质研究审评一般原则的补充说明

关于《疫苗生产用细胞基质研究审评一般原则》的补充说明――传代细胞残留 物质的考虑 审评五部生物制品室高恩明 摘要:本文对《疫苗生产用细胞基质研究审评一般原则》中细胞传代及其残留物要求的有关问题进行了重点阐述 目前,我国疫苗生产使用的传代细胞主要有两种,一种是非洲绿猴肾细胞的传代细胞系(V ero细胞)。另一种是中华仓鼠卵巢细胞的传代细胞系(CHO细胞),虽然《疫苗生产用细胞基质研究审评一般原则》不涉及CHO细胞的有关问题,但鉴于CHO细胞本身存在的问题及残留物质的重要性,本文对有关问题进行讨论。 CHO细胞主要作为表达载体,目前国内用于重组疫苗的表达,二十世纪九十年代上市的产品有重组乙型肝炎疫苗,现在仍有一些科研单位或企业正在研发某些重组疫苗,试图采用CHO细胞表达。 理论上,传代细胞的DNA和蛋白存在致肿瘤的可能性。目前国内的研究资料显示,CHO细胞致肿瘤试验阳性,逆转录酶试验阳性。为此,《中国药典》三部(2005版)对CHO 细胞表达的重组乙型肝炎疫苗提出新的要求,要求CHO细胞残余DNA含量≤10pg/剂量,CHO细胞残余蛋白占总蛋白含量的0.05%以下,并要求在生产工艺中增加病毒灭活工艺。在药品审评中,对于未上市的新疫苗的评价,除进行技术审评之外,还需要进行效益/风险比的分析与评价。虽然CHO细胞只作为表达载体,表达的目的蛋白尚需纯化,CHO细胞的残留物质很少,但是,仍存在潜在的风险,因此不推荐新的预防用疫苗采用CHO细胞表达,更不能推荐用于婴幼儿。 近几年,我国采用V ero细胞生产灭活疫苗逐渐增多,疫苗的种类包括人用狂犬病纯化疫苗、出血热纯化疫苗、甲型肝炎灭活疫苗、乙型脑炎纯化疫苗。V ero细胞是传代细胞系,理论上具有致肿瘤的可能性,已有资料报导,V ero细胞在170代以上致肿瘤试验阳性;WHO 推荐134~150代,认为在该代次内未发现致肿瘤性。因此,建议我国疫苗生产些企业尽可能采用150代作为使用限定代次。 V ero细胞残余DNA、残余蛋白(包括促生长蛋白)可能对人体有潜在的致肿瘤性及其他危害,建议疫苗生产研究单位研究特异性检测V ero细胞蛋白的方法,为今后制定相关质量控制标准奠定基础。此外,目前阶段应尽量降低疫苗总蛋白含量,间接控制细胞残留蛋白。关于V ero细胞残余DNA危害,除了与残余DNA含量的多少有关外,还与残余DNA 片断的大小有关,残余DNA含量越高、片断越大,其潜在的致肿瘤性越大。因此,建议疫苗生产研究单位强化纯化工艺,尽量降低残余DNA含量;此外,研究并建立检测V ero细胞残余DNA片断大小的方法,为今后制定相关质量控制标准奠定基础。 在上述采用V ero细胞生产的纯化疫苗中,乙型脑炎纯化疫苗比较特殊,因为它是国家一类疫苗,即实施计划免疫的疫苗,用于婴幼儿的免疫接种。因此,对乙型脑炎纯化疫苗的质量要求应相对严格,用于计划免疫婴幼儿使用的疫苗,采用V ero细胞生产是否合适,对于V ero细胞DNA残余量、残余蛋白含量如何要求有待讨论。目前可初步要求DNA残余量≤10pg//剂量(参照CHO细胞产品的要求),要求生产企业建立V ero细胞残余蛋白含量的检测方法并拟定质量标准。 作者:cde 发布时间:2008-6-13 10:47:18

2020年上海市高中英语翻译练习100句-详细解析

翻译100句练习 1. 我原打算在书店里消磨时间的,但最终买了本有关计算机的书。(end) I had meant/intended/ planned to kill time //I meant/ intended/ planned to have killed time in the bookstore, / but I ended up buying a book on computer. 考点一:end up doing 是固定词组 考点二:原打算做某事(had meant/intended/planned to do = meant/intended/planned to have done) 考点三:本句前后时态要一致,前面是过去完成时+to do 或过去时+to have done, 后面是一般过去时。 2. 如果你采用先进的方法,你就能取得事半功倍的效果。(effort) If you adopt the advanced method, you are able to achieve twice the result with half the effort. 考点一:事半功倍(twice the result with half the effort) 考点二:采用先进的方法(adopt the advanced method) 3.每一位驾驶员开车时都必须牢记,一点点疏忽都可能造成事故。(mind) When driving, every driver must keep/bear in mind that the slightest carelessness will cause an accident. 考点一:keep/bear in mind that 中间不加it 考点二:翻译过程中别漏掉“开车时” 4. 色彩鲜艳的药片可能被孩子们误当成糖果,因此应该把它们放在孩子们拿不着的地方。(thus, accessible) Brightly-colored pills may/can be mistaken for sweets by children, and thus they should be kept where they are not accessible to children. 考点一:被…误当成(be mistaken for) 考点二:thus是副词,不可直接引导句子 考点三:sth. is accessible to sb. 5.他从未想到过他的教育费用将花完他父母的所有积蓄。(occur, drain) It never occurred to him that the expenses for his education would be a great drain on all his parents’ savings 考点一:从未想到过(It never occurred to him that) 考点二:教育费用(the expenses for his education) 考点三 drain(n.) a great drain on sth. 6.许多家长发现,很难和自己的孩子交流。(find) Many parents find it difficult to communicate with their own children.

Remain用法总结

Remain用法总结 一.remain 作为不及物动词vi,有两种意思,但都不能用进行时态,也没有被动语态:1、remain 表示“剩下”、“余下”、“遗留”,例如: Only a few leaves remained on the tree. 树上只剩下几片叶子了。 2、remain 表示“留下”、“停留”、“呆在”,相当于“stay”例如: The Smiths remained there all through the year.史密斯一家人在那里呆了整年。 二. remain作为系动词,表示“保持”、“仍然是”,“依旧是”,后接形容词、名词、动词不定式、现在分词、过去分词或介词形容词短语作表语,指某人或某事物仍保持某种状态。 He remained silent. 他保持沉默。(接形容词) It remained a secret. 这仍然是个秘密。(接名词作表语) 指某事尚待、有待于以后被处置,后面常接不定式的被动形式,表示主语是不定式的承受者。 A lot of work remained to be done.许多工作还有待完成。(接动词不定式) He had to remain in hospital until he was better. 他不得不一直住院直到身体好些。(接介词短语作表语) After the earthquake,very few houses remained standing.地震之后几乎没有房子还矗立着。(接现在分词作表语,表示正在进行的主动动作) As before, he remained unmoved. 他和以往一样无动于衷。(接过去分词作表语,表示主语所处的状态或已经发生的被动动作) 三、remains作为名词,表示“遗物”、“遗址”,“剩余物”,其单复数形式相同。 The remains of an old castle still stands there silently beside the river. 古城堡的遗址如今仍默默地矗立在河岸边。 The remains of the meal has been taken away. 剩饭菜都被拿走了。 The archeologists found some remains of the Song Dynasty. 考古学家发现了一些宋代遗迹。 四、remaining 是形容词,表示“剩下的”、“余下的”,修饰单个名词作定语,置于该名词之前作前置定语,与left同义,left必须置于被修饰的名词之后作后置定语,试比较:She returned home with the remaining 10 dollars. She returned home with the 10 dollars left. 她带着剩下的十美元回到了家。 五.Remain的一些常用词组 ~+名词 remain a bachelor 还是单身remain a complete mystery 一直是个谜remain a fisherman 仍是个渔民remain a little money 只剩一点点钱remain a little water 只剩一点水remain a question 还是一个问题remain a shining example 永远是闪光的榜样remain good friends 仍然是好朋友remain principles 保持原则remain the chief means 还是主要方式 ~+形容词 remain active 仍然活跃remain closed 仍然未开放remain confused 迷惑不解remain constant 保持不变remain expressionless 毫无表情remain hungry 只好饿着remain linked 还连在一起remain long 保持得很久remain modest 保持谦虚remain motionless 仍然不动remain prudent 保持谨慎remain silent 保持沉默remain unchanged 依然不变remain unconvinced 仍然不相信remain unfinished 仍然未完成remain unknown 依旧不详remain unsettled 仍然未解决 副词+~ always remain 仍然保持hardly remain 没剩下little remain 没剩下

remain的用法小结

remain的用法小结 你们知道remain的用法吗?我们一起来学习学习吧,下面就和大家分享,来欣赏一下吧。 remain的用法 remain有名词和动词的词性。作名词有剩余物,残骸,遗迹等含义;作动词时,通常用作不及物动词和系动词,有保持不变,剩余等含义。 1remain的释义n. 剩余物,残骸;残余;遗迹;遗体 v. 仍然是; 保持不变; 剩余; 遗留; 继续存在; 仍需去做(或说、处理); 第三人称单数:remains 现在分词:remaining 过去式:remained 过去分词:remained 2remain的用法1.用作不及物动词 They went, but I remained. 他们走了,但我留了下来。 Hell remain to accompany you.

他将留下来陪你。 A number of problems remain to be solved. 有很多问题尚待解决。 还有一项更艰苦的工作需要我们做。 2.用作系动词 They remained good friends. 他们仍然是好朋友。 He will always remain a shining example for us all. 他永远是我们学习的光辉榜样。 His face remained expressionless. 他的脸上仍然毫无表情。 In spite of the danger they remained calm. 尽管有危险,但他们一直保持冷静。 We must always remain modest and prudent. 我们要经常保持谦虚谨慎。 He remained hanging in midair, saved by the belt.

remain用法大全

Use of "remain" 下面将remain的用法归纳如下: 一、用作联系动词,指某人或某事物仍保持某种状态,意为“仍然;依旧”,“留;呆;住;待”,后面可接名词、代词、形容词、介词短语、分词作表语。 1. 接名词作表语 Peter became a manager, but Jack remained a worker. 彼得成为了一个经理,而杰克仍然是个工人。 It remained a secret. 这仍然是个秘密。 2. 接形容词作表语 Whatever achievements you’ve made, you should remain modest. 无论你取得多么大的成就,你都该保持谦虚。 3. 接介词短语作表语 He had to remain in hospital until he was better. 他不得不一直住院直到身体好些。 4. 接分词作表语 接过去分词作表语,表示主语所处的状态或已经发生的被动动作;现在分词作表语,表示正在进行的主动动作。 The guests came in, but she remained sitting at the desk reading. 客人们都来了,但她还坐在写字台旁读书。

As before, he remained unmoved. 他和以往一样无动于衷。 二、用作不及物动词,意思是“剩下;剩余;遗留”,此时不能用进行时态,也没有被动语态。 After the fire, very little remained of his house. 火灾过后,他的家所剩无几。 After the earthquake, very little remained of the city of Tangshan. 地震过后,唐山这座城市所剩无几。 三、指某事“尚待、有待于以后被处置”,后面常接不定式的被动形式,表示主语是不定 式的承受者。 Many problems remain to be solved. 有好多问题尚待解决。 It remains to be seen whether you are right. 你是否正确,以后见分晓。 四、remain作名词 remain作名词时表示“剩余物”,一般用其复数形式。例如: The archeologists found some remains of the Song Dynasty. 考古学家发现了一些宋代遗迹。 五、remaining的用法 remaining是形容词,意为“剩余的”,常作前置定语;而left则只能作后置定语。例如: There are still some apples left. 还剩余一些苹果。 I bought a gift for her with the remaining money. 我用剩余的钱给

外源DNA残留量测定(荧光定量PCR法)标准操作规程SOP

外源性DNA残留量测定法(荧光定量PCR法) 标准操作规程 文件编码:XXXXXX

目录 1.目的 (1) 2.范围 (1) 3.职责 (1) 4.依据 (1) 5.定义 (1) 6.内容 (1) 6.1.原理 (1) 6.2.实验材料 (1) 6.3.操作步骤 (3) 6.4.结果计算 (6) 6.5.判定标准 (7) 6.6.注意事项 (7) 7.相关文件 (7) 8.附件 (7) 9.变更历史 (7)

1.目的 1.1.规范外源性DNA残留量测定法(荧光定量PCR法)的操作过程。 2.范围 2.1.本规程适用于采用荧光定量PCR法对CHO细胞表达产品进行外源性DNA残留 量的测定。 3.职责 3.1.方法学研究员负责严格执行本规程规定; 3.2.质量研究室负责人负责本规程的培训并监督本规程的执行。 4.依据 4.1.DNA残留量检测样品处理试剂盒(PrepSEQ TM Residual DNA Sample Preparation kit,Applied Biosysterms)使用说明书。 5.定义 5.1.LTR:long tandem repeat,长串联重复序列 5.2.PCR:Polymerase Chain Reaction,聚合酶链式反应 5.3.Ct:阈值循环,即荧光信号强度超过设置的阈值强度时所经历的循环数 6.内容 6.1.原理 CHO工程细胞所表达的蛋白质产品,其外源性DNA残留量的测定采用荧光定量PCR法。该方法是以荧光定量PCR仪为设备平台基础,选择CHO细胞中含量较丰富的一段LTR(long tandem repeat,长串联重复序列)为靶标序列设计扩增引物,建立基于Taqman探针的定量检测实验。用已知量的CHO细胞基因组DNA做标准曲线,通过对Ct值进行线性回归计算样品中DNA的含量。 6.2.实验材料

高考词汇remain用法终结篇

高考词汇remain用法终结篇 Remain首先用作不及物动词,表示【留下,剩下】 如She remained where she was.(她留在原来的地方)。 它用作联系动词时,意思是【保持(某种状态)】,有下面四种句型: 1. 跟形容词 He remained poor for a long time. 长时间他都很穷。 Jim was trying very hard to remain calm. 吉姆极力保持镇静。 Elizabeth remained silent. 伊丽莎白一直没讲话。 She remained unconscious for several hours. 她不省人事有好几个小时。 2. 跟名词 I want to remain friends with you. 我想继续和你做朋友。 These two deaths have remained a mystery. 这两人的死一直是一个谜。 The pattern remains the same throughout a lifetime. 这个模式一生都不会变。 In spite of their quarrel, they remain the best of friends. 尽管有过争吵,他们仍是最好的朋友。 He will remain (as) manager of the club until the end of his contract. 他将继续担任俱乐部经理,直至合同期满。 This, coupled with the fact that flying machines remained universally a subject for jeers and derision, made the brothers secretive. 这一点,加上飞行器仍是人们普遍嘲笑和讥讽的对象,使得兄弟俩只能暗地里行事。 3. 跟分词 Train fares are likely to remain unchanged.火车票价很可能会保持不变。 This site remained undiscovered, though long sought, until recent times. 虽经长期寻找,但该遗址直到最近才被发现。 He remained unmoved after I had talked with him for hours. 虽然我同他说了数小时,他仍无动于衷。 David's murder remains unsolved. 戴维被杀的案子仍未侦破。 My opinion remains unchanged. 我的看法一如既往。 4. 跟从句

remain用法总结

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连系动词用法详解

连系动词用法详解 连系动词本身有一定词义,但不完整,不能独立作谓语,必须与表语一起构成合成谓语。 一 . 连系动词分类 1. “状态”类:常见的有:be (是),keep (保持),stay (保持),remain (依然),seem (似乎是),appear (似乎,显得),prove (证明是),这类词表示具有或保持某种特征或状态。 ① He is director of our department.他是我们部门的主任。 ② The meat will keep/stay fresh for several days.肉会保鲜好几天的。 ③ The store remains closed.What’s the matter? 已经是上午十点了,商店仍然关着门,是怎么回事? ④ The chairwoman seemed very surprised about the question I asked. 女主席似乎对我提出的问题感到吃惊。 ⑤ The sky appears blue on the earth.从地球上看天空似乎是蓝色的。 ⑥ As time went on,his theory proved (to be) true. 随着时间的推移,他的理论证明是正确的。 ◆◆keep, remain, stay用法区别 ① keep “保持……状态”,后接adj.或介词短语。其后常见:alive, awake, cheerful, silent, dry, well, fit, fine, close, clean, happy, firm,in one’s stand等。Have you kept well all these years? 这些年来你身体好么? I hope it will keep fine. 我希望天气继续好下去。 In order to keep fit, all students go in for sports. 为了保持健康,所有学生都参加体育运动。 We’d better keep in touch. 我们最好保持联系。 ②remain “仍然存在……状态”,后接adj.、过去分词、名词或介词短语,强调某种状态前后无变化。 The door remained closed.门仍然关着。 Kosovo intensity remained high.科索沃局势仍然高度紧张。 Peter became a judge but John remained a fisherman.彼得当了法官,而约翰依旧是渔民。 Your room remains like this. 你的房间依旧是这样子。 ③ stay “保持……状态”,后接形容词、分词。 That fellow stayed single. 那个小伙子仍保持单身。 The door stayed closed. 门一直关着(无比较的持续状态) It’s easy to stay hidden. 躲起来很容易。 Please stay seated. 请继续坐着。 2. “感官”类:主要指与五种感官有关的动词:look (看起来),sound (听起来),smell (闻起来),taste (尝起来),feel (摸起来 / 感到)。

remain+用法

remain 1. link-v. 保持,仍然是;(后接n., adj. , pp. –ing, 介词短语) eg: You have the right to remain silent. 你有权保持沉默。 People in some parts of Africa remain in deep poverty. The room remained unchanged after the girl was killed in the accident.

It remains an important part of everyday life in Britain, especially for teenagers. 2. vi. 留在某处;剩下 She remained at home to look after the children. 她留在家里照顾孩子。 Let things remain as they

are! 一切顺其自然吧! After the flood, nothing remained of the village. 洪水过后,村子什么也没剩下。 If you take 5 away from 8, 3 remains. 3. 常用句型: ….remain to be seen 尚不确定;说不准; 拭目以待 Eg: Whether it will do us

harm or good remains to be seen. …. r emain to be done …有待去做 Eg: Many questions remain to be answered. 许多问题有待回答。 The fact remains that…. 不能忽略的是… Eg: I know he has a PH. D, but the fact remains

(山东)《龙门亮剑》2020高三英语一轮 Unit1 语法探究(

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