不可或缺

It is universally acknowledged that trees are necessary to us.

人们普遍认为树木对我们是不可或缺的。

The major function of nebulin is to act as a unique regulator of thin filament length, a vital modulator of actomyosin sliding, and a biomolecular sensor of signal transduction.

Nebulin主要功能为扮演细肌丝长度的独特性调节者，肌凝蛋白与肌动蛋白滑动之不可或缺的调控者，以及讯息传递的生物分子成应者。

For over 80 years, adidas has been part of the world of sports on every level.

在过去的80多年中，adidas已成为世界各级运动的不可或缺的一分子。

Diligent is an adman 's essential condition .

勤奋是一个广告人不可或缺的重要品质。

In order to ensure the source of milk quality and food safety, checking 42 pastures randomly found that poor milking environment, the scene mismanagement and artificially adulterate serious problem.

随着社会的进步，人民群众的生活水平的不断提高，牛奶作为一种营养全面的全价食物，已经成为人们每天生活中不可或缺的营养品。

Generally, the relative affectionateness level of junior middle school students is relatively low; parents can\'t take on their charges effectively; social distance is relatively far between teacher and students; student like the class but unacceptable; Internet has infiltrated in daily life; the institution and faculty provided by community is not enough; partner is indispensable in junior middle school students\' life and new characters about the intercourse appeared. Each group has different influence on social cognition.

研究发现：当前初中生家庭亲情水平普遍较低；父母不能有效承担自己的角色；师生社会距离较远；学生喜欢班级但不被接纳；网络已经渗透到同常生活；社区提供的活动机构和设施并不丰富；同伴在初中生生活中仍然不可或缺，交往具有新的特征。

The game is not an incidental part of Afrikaner culture, like cricket is to the English.

橄榄球对于南非白人就如板球之于英国人般不可或缺。

The pump and the air blower already became present to produce the indispensable machinery, each has their form in national economy's all quarters, therefore understood that their performance is not big regarding the production help.

泵与风机已经成为了现在生产中不可或缺的机械，在国民经济的各方各面都有它们的身影，因此了解它们的性能对于生产的帮助来说不可谓不大。

During the postgenomics era the information about genomic sequence and gene functions provides a new foundation for evolutionary biology and ecology As the first whole-genome sequenced plant Arabidopsis thaliana and its wild relatives have played a critical role in understanding the evolution of genomics and speciation Both A halleri and A lyrata are closely related to the model species A thaliana A halleri ssp gemmifera occurs in northeastern China Japan and Taiwan; while its sister A halleri ssp halleri is mainly distributed in Europe Geographical barriers such as Tienshan Mountain Range isolate these intraspecific sisters Likewise A lyrata ssp kamchatica and ssp lyrata occur in East Asia and North America respectively Such distribution patterns seem to be consistent with allopartic speciation The comparison between ancestral and extant polymorphism by multilocus can be informative about the population genetics of speciation In this study we collected and analyzed DNA sequences of 98 genes from four wild relatives of A thaliana A halleri ssp gemmifera A halleri ssp halleri A lyrata ssp kamchatica and A lyrata ssp lyrata The ancestral states of these four species were compared to each other in terms of level of genetic variation However the ancestral species at the time of speciation were substantially more polymorphic than the extant geographical populations The observations are not fully compatible with speciation by strict allopatry At some species pairs parapatric speciation seems more reasonable in speciation of Arabidopsis The 98 gene sequences are also used for the congruence test between gene genealogy and species phylogeny Only 28 genes support the species phylogeny but there are 23 genes supports another major genealogy { lyrata} thaliana Based on the phylogenetic position change of A lyrata ssp kamchatica and Ks value for each species pair suggested the recent directional gene flow between A halleri ssp gemmifera and A lyrata ssp kamchatica

阿拉伯芥是第一个完成基因体定序的开花植物，其基因体资讯提供植物学研究的重要依据；在解析阿拉伯芥属物种的亲缘关系以及种化机制等重要的演化议题时，阿拉伯芥近缘的野生物种自然成了不可或缺的关键；跟阿拉伯芥近缘的物种包括A halleri及A lyrata，其中A halleri ssp gemmifera主要分布於中国东北、日本以及台湾，与近缘的A halleri ssp halleri其分布於欧洲隔著天山及大陆的障蔽，而A lyrata ssp kamchatica主要分布於东北亚及台湾，与分布於北美五大湖的A lyrata ssp lyrata被北极圈所分隔，这样的分布模式暗示异域种化的可能。藉由多基因分析比较祖先物种与现生物种遗传歧异度的相关可提供讯息探讨种化时期的族群遗传结构，本研究针对A halleri ssp gemmifera、A halleri ssp halleri及A lyrata ssp kamchatica、A lyrata ssp lyrata四个物种，两对互为亚种的姊妹群，以阿拉伯芥为外群进行研究，在四个物种完成98个同源基因的分子序列，利用套装软体MCMCcoal来估算祖先物种的遗传变异，亦估算现生物种的核苷酸歧异度，观察到？多物种配对中祖先物种遗传多型性大於现生物种DNA歧异度，显示异域种化模型并无法完全解释阿拉伯芥属物种的种化模式，在某些物种配对间邻域种化模式应比异域种化更为可能；在基因树与物种树的比较，98个基因片段的亲缘模式只有28个是与已知物种树一致的，有23个基因其树状图支持{ lyrata} thaliana的型式，藉由kamchatica位置的变化以及估算各物种配对间的平均同义置换率，推测在A halleri ssp gemmifera与A lyrata ssp kamchatica间具有近代的单方向基因交流。

Methods Under general anesthesis, tracheotomy was done in 6 adult sheep, warm physiological saline was used to lavage the respiratory, followed by alveolar lavaged via tract through bronchofiberscope to reproduce acute respiratory distress syndrome.

自1967年急性呼吸窘迫综合征被发现以来，PV曲线的重要性便得到了广泛的认可〔1〕。随着曲线描记技术的不断改善，人们对PV曲线的认识也越来越深刻，不断有研究成果直接应用于ARDS患者的通气支持〔2〕，使PV曲线成为指导ARDS患者机械通气不可或缺的工具。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。