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1.
Bengü Ergüden 《Yeast (Chichester, England)》2019,36(2):99-105
The correct separation of chromosomes during mitosis is necessary to prevent genetic instability and aneuploidy, which are responsible for cancer and other diseases, and it depends on proper centrosome duplication. In a recent study, we found that Smy2 can suppress the essential role of Mps2 in the insertion of yeast centrosome into the nuclear membrane by interacting with Eap1, Scp160, and Asc1 and designated this network as SESA (S my2, E ap1, S cp160, A sc1). Detailed analysis showed that the SESA network is part of a mechanism which regulates translation of POM34 mRNA. Thus, SESA is a system that suppresses spindle pole body duplication defects by repressing the translation of POM34 mRNA. In this study, we performed a genome-wide screening in order to identify new members of the SESA network and confirmed Dhh1 as a putative member. Dhh1 is a cytoplasmic DEAD-box helicase known to regulate translation. Therefore, we hypothesized that Dhh1 is responsible for the highly selective inhibition of POM34 mRNA by SESA. 相似文献
2.
陈丹生 《吉林化工学院学报》2003,20(2):24-27
光调节的叶绿体mRNA的翻译需要mRNA5′,非翻译区(5′ UTR)相互作用的中间作用因子.叶绿体多聚腺苷酸结合蛋白(cPABP)RB47特异性地与PsbAmRNA的5′ UTR结合,并对于该mRNA的翻译是很重要的.定位于叶绿体中与cPABP伴随纯化出来的一种蛋白质二硫化物异钩酶RB60表现出调节cPABP与PsbAmRNA的5′ UTR结合的特性.这种调节是通过可逆地改变有氧化还原特征的cPABP的氧化还原状态来实现,或通过ADP依赖的磷酸化来实现.这种机制就在调节叶绿体的基因表达中提供了一个简单可逆的开关机制. 相似文献
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4.
对含Karnopp摩擦的柔性滑移铰系统进行动力学建模和仿真.将滑移铰中的滑块视为柔性体,滑道视为刚性接触面,考虑滑道与滑块之间的间隙.由于柔性滑块与滑道的接触状态和摩擦情况比较复杂,采用有限元方法建立了柔性滑块的力学模型,基于罚函数方法建立含Karnopp摩擦柔性滑移铰接触力模型,通过试算迭代法判断柔性滑块各节点的接触状态,基于KED方法和Newmark方法给出了含该滑移铰机械系统动力学方程的数值算法.最后,以含Karnopp摩擦的柔性滑移铰和驱动摆杆构成的机械系统为例进行动力学仿真,分析了其动力学特性,验证了本文给出的方法的有效性. 相似文献
5.
论文对一种三平移并联机器人进行了运动学建模,运用矩阵计算方法得到其机构运动学反解,即根据终端执行器的运动规律,求出原动件在单位时间内的位移,进而求得步进电机在单位时间内所发的脉冲数。实验验证该步进电机控制算法的正确性,为并联机器人的运动控制提供了理论方法。 相似文献
6.
一种快速模板匹配目标识别算法 总被引:8,自引:0,他引:8
该文拟将计算机视觉中传统模板匹配方法与对场景物体的中心矩描述方法相结合,提出了一种效率较高的匹配算法。算法在匹配识别上不仅不受物体方位旋转及尺寸缩放变化影响,而且能较精确地求出物体相对于模板的缩放比例和偏转角度。文中给出了与传统模板匹配算法对照的实验结果。 相似文献
7.
Urine is a human specimen that is easily obtained non-invasively for clinical diagnosis. We attempted to enhance the resolution of current human urine proteomes and construct a comprehensive reference database for advanced studies, such as the discovery of biomarkers for renal diseases. Multi-dimensional LC-MS/MS was coupled with de novo sequencing and database matching. The proposed approach improved the identification of not only the proteins, but also the post-translational sites of urinary proteins. We identified 165, 200 and 259 unique gene products in the urine proteomes from males, females and pregnant women, respectively. When all of the results were combined and the redundancies removed, a total of 1095 distinct peptides were identified. Of these, 1016 peptides were associated with 334 unique gene products. In this study, over 100 gene products, including some disease-related proteins, were detected in urine for the first time by proteomic approaches. Various proteins with novel post-translational hydroxylation were identified using the MASCOT program and de novo sequencing. All proteins with peptide information were summarized into a comprehensive urine protein database. We believe that this comprehensive urine proteome database will assist in the identification of urinary proteins/polypeptides whose spectra are difficult to interpret in the discovery of urinary biomarkers. 相似文献
8.
Kai Tang Ming-En Wang Lin-Lin Chen Shuo-Yan Chou Tony C. Woo Ravi Janardane 《Computer aided design》1997,29(12):825-836
A translational sweep is the translating of a polygon, called the generatrix G, around another polygon, called the directrix D, under two conditions: (1) G is always in contact with D; and (2) the interiors of G and D do not intersect. Three classes of translational sweep are studied, including the case in which both G and D are convex; the case in which G is convex, D monotone; and the case in which both are monotone. Efficient algorithms for computing the trajectory and the swept area as well as geometric and computational properties are presented for each class. A notion called the inverse generatrix, which reveals a duality between the trajectory and the swept polygon, is introduced to reduce complexity. 相似文献
9.
Cytomegalovirus (CMV) syndrome and infectious disease are defined as pathogen detection with appropriate clinical symptoms, but there are not pathognomonic signs of CMV disease. Although the prodrome of acute minor viral infections leukopenia (lymphopenia and neutropenia) is noted with onset of fever, followed by monocytosis, the role of monocytosis in CMV disease has not been described. Furthermore, under influence of corticosteroid therapy, CMV reactivation and monocytosis are described, but without a strict relationship with steroids dose. In the study, the monocyte level was investigated during the CMV infectious process. Regrettably, a non-selected group of 160 patients with high CMV viremia showed high dispersion of monocyte level and comparable with the median value for healthy subjects. Therefore, we investigated monocyte level in CMV-infected patients in relation to the logarithmic phase of the infectious process. Samples from patients with active CMV replication (exponential growth of CMV viremia) were tested. Significant monocytosis (above 1200/µL) during the logarithmic phase of CMV infection (with exponent between 3.23 and 5.77) was observed. Increased count and percentage of monocytes correlated with viral replication in several clinical situations except when there was a rapid recovery without relapse. Furthermore, glucocorticoids equivalent to 10 and 20 mg of dexamethasone during a 2–3-week period caused monocytosis—significant increase (to 1604 and 2214/µL, respectively). Conclusion: In light of the logarithmic increase of viral load, high monocytosis is a hallmark of CMV replication. In the COVID-19 era, presence of high virus level, especially part of virome (CMV) in the molecular technique, is not sufficient for the definition of either proven or probable CMV replication at any site. These preliminary observations merit additional studies to establish whether this clinical response is mediated by monocyte production or by decrease of differentiation to macrophages. 相似文献
10.
随着红外成像制导技术的发展,它对制导跟踪算法的精度和实时性的要求越来越高。制导系统已被要求在20 ms的时间内输出跟踪结果。某些跟踪算法虽然效果较好,但达不到实时输出。经典的制导算法-相关跟踪算法主要基于像素灰度特征进行跟踪,无法解决跟踪过程中由于目标的旋转、膨胀以及仿射变换带来的跟踪点漂移问题。为了解决经典相关跟踪算法无法解决图像旋转时的跟踪稳定性问题以及目标图像急剧膨胀时的跟踪点漂移问题,研究了图像不变矩的特征。利用图像不变矩的旋转-伸缩-平移不变性,选择合适的不变矩特征用于跟踪。通过用归一化的乘法相关函数以及基于相关系数值的模板更新策略设计跟踪算法,解决了复杂背景及强噪声条件下不能对尺寸和形状发生变化的目标进行稳定跟踪的问题。 相似文献