必需的

In vitro SUMO modification of the BRCA1/BARD1 heterodimer greatly increases its ligase activity, identifying it as a SUMO-regulated ubiquitin ligase. Further, PIAS SUMO ligases are required for complete accumulation of double-stranded DNA damage-repair proteins subsequent to RNF8 accrual, and for proficient double-strand break repair.

Galenty等人发现，两个连接酶（PIAS1 和 PIAS4）在DNA双链断裂处将各种不同的SUMO蛋白添加到DNA修复蛋白上，而SUMO蛋白则是泛素随后修饰这些蛋白中的其中一些所必需的。

The price of using DHA as plasma membrane is very high.

同时，DHA也是精子所必需的，DHA水平低的精子连动都难，会动的受精能力也非常差。

Our results show that active pollination is not essential for the reproduction of the pollinator, but does improve its reproductive success.

研究结果说明传粉榕小蜂的主动传粉对其繁殖不是必需的，但是主动传粉能增加其繁殖成功的几率。

The duration parameter is required; only a positive number, zero, or all is allowed.

时间参数是必需的；唯一的正数，零，或全部是允许的。

In this article author measured the principal element and trace element of Maifanshi with X-ray fluorescence spectrometric method of analysis.

本文用X-射线荧光光谱分析法对麦饭石中的主元素和微量元素进行了测定，测定结果达到检出线的有24种，其中有些是人体所必需的元素。

Vitamin E, or tocopherol, is a lipid-soluble antioxidant and essential for human health. 2-methyl-6-phytyl-1, 4-benzo- quinol methyltransferase, one of the key enzymes in vitamin biosynthetic pathway in plants, converts 2-methyl- 6-phytyl-1,4-benzoquinol to 2,3-dimethyl-6-phytyl-1,4-benzoquinol.

维生素E是一类人体必需的脂溶性抗氧化剂，具有重要的生理功能。2-甲基-6-叶绿基-1，4-苯醌甲基转移酶是天然维生素E合成途径中的关键酶之一，催化MPBQ甲基化，生成DMPBQ。

Please review the readme file for required references and other information about the application.

请参看帮助文件获得必需的参考和其它的关于这个应用程序的信息。

Para 1: The biggest headache in the program as it is currently written is the regular expression, which is required because you have no other way of breaking down a Roman numeral.

现在写的这个程序中最令人头痛的性能负担是正则表达式，但它是必需的，因为没有其它方法来识别罗马数字。

Disruptants of sanA lost the ability to produce nikkomycin, indicating that sanA is essential for nikkomy biosynthesis.

野生株中sanA的破坏导致失去尼可霉素的合成能力，表明sanA是尼可霉素生物合成所必需的。

Appropriate dress is a must so as to avoid sartorial humiliation amongst the cubicles.

合适的服装是必需的，借此避免在办公室遭到讽刺的羞辱

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。