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101.
Svetlana A. Smirnikhina Milyausha I. Zaynitdinova Vasilina A. Sergeeva Alexander V. Lavrov 《International journal of molecular sciences》2022,23(11)
Genome editing is currently widely used in biomedical research; however, the use of this method in the clinic is still limited because of its low efficiency and possible side effects. Moreover, the correction of mutations that cause diseases in humans seems to be extremely important and promising. Numerous attempts to improve the efficiency of homology-directed repair-mediated correction of mutations in mammalian cells have focused on influencing the cell cycle. Homology-directed repair is known to occur only in the late S and G2 phases of the cell cycle, so researchers are looking for safe ways to enrich the cell culture with cells in these phases of the cell cycle. This review surveys the main approaches to influencing the cell cycle in genome editing experiments (predominantly using Cas9), for example, the use of cell cycle synchronizers, mitogens, substances that affect cyclin-dependent kinases, hypothermia, inhibition of p53, etc. Despite the fact that all these approaches have a reversible effect on the cell cycle, it is necessary to use them with caution, since cells during the arrest of the cell cycle can accumulate mutations, which can potentially lead to their malignant transformation. 相似文献
102.
在嵌入式领域,操作系统是嵌入式系统的基石,一旦遭受攻击,运行其上的关键功能的安全性将无法保证,因此需要一套安全防护体系,能够在操作系统运行周期的各个阶段实施安全防护.架构是所有体系设计的基础,主动防护体系架构设计的优劣与体系的防护效果以及系统的性能直接相关.本文设计了一种面向嵌入式操作系统的信息安全防护体系架构,将各阶... 相似文献
103.
为适应未来信息化作战的需要,优化舰炮武器装备的维修保障工作,探讨4D 打印技术在全寿命周期维
修保障中的应用。将舰炮武器装备的维修保障提前至论证决策阶段,并贯穿全寿命周期,分析4D 打印技术原理,
梳理维修保障的关键问题,以期拓展信息化作战条件下舰炮武器装备的维修保障工作思路。结果表明,4D 打印技术
为相关研制部门和一线作战使用单位提供参考依据。 相似文献
104.
Yixuan Cui Ying Jiang Meng Xiao Muhammad Zeeshan Munir Sadaf Riaz Faiz Rasul Maurycy Daroch 《International journal of molecular sciences》2022,23(9)
Ethylene is an essential platform chemical with a conjugated double bond, which can produce many secondary chemical products through copolymerisation. At present, ethylene production is mainly from petroleum fractionation and cracking, which are unsustainable in the long term, and harmful to our environment. Therefore, a hot research field is seeking a cleaner method for ethylene production. Based on the model ethylene-forming enzyme (Efe) (6vp4.1.A) from Pseudomonas syringae pv. phaseolicol, we evaluated five putative Efe protein sequences using the data derived from phylogenetic analyses and the conservation of their catalytic structures. Then, pBAD expression frameworks were constructed, and relevant enzymes were expressed in E. coli BL21. Finally, enzymatic activity in vitro and in vivo was detected to demonstrate their catalytic activity. Our results show that the activity in vitro measured by the conversion of α-ketoglutarate was from 0.21–0.72 μmol ethylene/mg/min, which varied across the temperatures. In cells, the activity of the new Efes was 12.28–147.43 μmol/gDCW/h (DCW, dry cellular weight). Both results prove that all the five putative Efes could produce ethylene. AAD16440.1相似文献
105.
Daniella Cesar-Silva Filipe S. Pereira-Dutra Ana Lucia Moraes Giannini Cecília Jacques G. de Almeida 《International journal of molecular sciences》2022,23(9)
This review aims to describe and discuss the different functions of the endolysosomal system, from homeostasis to its vital role during viral infections. We will initially describe endolysosomal system’s main functions, presenting recent data on how its compartments are essential for host defense to explore later how SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) and other coronaviruses subvert these organelles for their benefit. It is clear that to succeed, pathogens’ evolution favored the establishment of ways to avoid, escape, or manipulate lysosomal function. The unavoidable coexistence with such an unfriendly milieu imposed on viruses the establishment of a vast array of strategies to make the most out of the invaded cell’s machinery to produce new viruses and maneuvers to escape the host’s defense system. 相似文献
106.
目的 针对9H级燃气-蒸汽联合循环机组主厂房结构设计方案研究,找出最佳的主厂房布置。 方法 通过结构型式、计算方法及设计参数取值进行优化,对技术、初投资、建设工期及施工组织等方面进行详细论述与分析。 结果 分析结果表明:钢筋混凝土结构与钢结构均为可行的,考虑经济性等诸多因素,推荐采用钢筋混凝土结构,屋面采用钢屋架。 结论 主厂房结构采用钢筋混凝土结构,屋面主承重结构采用钢屋架。 相似文献
107.
108.
A limit cycle is the stability boundary for linear and non-linear control systems. Hamiltonian mechanics and power flow control are employed to demonstrate this property of limit cycles. The presentation begins with the concept of linear limit cycles which is extended to non-linear limit cycles. Many examples are used to demonstrate these concepts including linear and non-linear oscillators, power engineering, and an extension to a class of plane differential systems. Power flow control based on Hamiltonian mechanics is shown to be applicable to a large class of non-linear systems. Finally, eigenanalysis and flight stability for linear systems are extended to non-linear systems and is referred to as ‘the power flow principle of stability for non-linear systems’. 相似文献
109.
本文以某运行近25年的老旧变电站500kV电力变压器为实例研究了变压器设备的全生命周期成本为实例,基于某该变电站运行多年以来的运行数据,对该站主变的材料、性能、运行工况进行分析,结合20年前生产制造的工艺、水平和技术能力,考虑包括初始投资成本、运行成本、检修维护成本、故障成本以及退役处置成本,对某变电站500kV主变压器的全寿命周期成本进行综合评估,并通过电力变压器对合资品牌以及国产优质品牌2个质量水平的产品进行分析比较,得出了设备购置成本对LCC的控制起到主导作用,在检修维护成本、故障成本以及退役处置成本占比不大的情况下,合资品牌产品较高的设备购置费用不利于成本的控制,国产优质品牌产品的全寿命周期成本相对更优的结论 相似文献
110.