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Mitochondria, as the main site of cellular energy metabolism and the generation of oxygen free radicals, are the key switch for mitochondria-mediated endogenous apoptosis. Ca2+ is not only an important messenger for cell proliferation, but it is also an indispensable signal for cell death. Ca2+ participates in and plays a crucial role in the energy metabolism, physiology, and pathology of mitochondria. Mitochondria control the uptake and release of Ca2+ through channels/transporters, such as the mitochondrial calcium uniporter (MCU), and influence the concentration of Ca2+ in both mitochondria and cytoplasm, thereby regulating cellular Ca2+ homeostasis. Mitochondrial Ca2+ transport-related processes are involved in important biological processes of tumor cells including proliferation, metabolism, and apoptosis. In particular, MCU and its regulatory proteins represent a new era in the study of MCU-mediated mitochondrial Ca2+ homeostasis in tumors. Through an in-depth analysis of the close correlation between mitochondrial Ca2+ and energy metabolism, autophagy, and apoptosis of tumor cells, we can provide a valuable reference for further understanding of how mitochondrial Ca2+ regulation helps diagnosis and therapy.  相似文献   
33.
Glycogen synthase kinase-3 (GSK-3) is a nonreceptor serine/threonine protein kinase that is involved in diverse processes, including cell development, photomorphogenesis, biotic and abiotic stress responses, and hormone signaling. In contrast with the deeply researched GSK family in Arabidopsis and rice, maize GSKs’ common bioinformatic features and protein functions are poorly understood. In this study, we identified 11 GSK genes in the maize (Zea mays L.) genome via homologous alignment, which we named Zeama;GSKs (ZmGSKs). The results of ZmGSK protein sequences, conserved motifs, and gene structures showed high similarities with each other. The phylogenetic analyses showed that a total of 11 genes from maize were divided into four clades. Furthermore, semi-quantitative RT-PCR analysis of the GSKs genes showed that ZmGSK1, ZmGSK2, ZmGSK4, ZmGSK5, ZmGSK8, ZmGSK9, ZmGSK10, and ZmGSK11 were expressed in all tissues; ZmGSK3, ZmGSK6, and ZmGSK7 were expressed in a specific organization. In addition, GSK expression profiles under hormone treatments demonstrated that the ZmGSK genes were induced under BR conditions, except for ZmGSK2 and ZmGSK5. ZmGSK genes were regulated under ABA conditions, except for ZmGSK1 and ZmGSK8. Finally, using the yeast two-hybrid and BiFC assay, we determined that clads II (ZmGSK1, ZmGSK4, ZmGSK7, ZmGSK8, and ZmGSK11) could interact with ZmBZR1. The results suggest that clade II of ZmGSKs is important for BR signaling and that ZmGSK1 may play a dominant role in BR signaling as the counterpart to BIN2. This study provides a foundation for the further study of GSK3 functions and could be helpful in devising strategies for improving maize.  相似文献   
34.
通过二步法合成了一系列具有6个亚甲基间隔基的双子咪唑类离子液体表面活性剂[Cn-6-Cn]Br2(n=10,12.14),并且通过红外光谱及核磁氢谱对其结构进行了表征.利用表面张力及电导率法研究了[C n-6-Cn]Br2(n=10、12、14)在水溶液中的聚集特性.结果表明:[C14-6-C14]Br2具有较好的表面...  相似文献   
35.
频率上转换掺稀土氧氟纳米微晶玻璃的研究进展   总被引:3,自引:0,他引:3  
综述了近年来用于上转换发光的掺稀土离子氧氟微品玻璃的研究概况,阐述了氧氟微品玻璃作为上转换发光材料的发展和研究中问题,提出了值得进一步研究的工作并对掺稀土离子氧氯微晶玻璃未来的前景作了展望。  相似文献   
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Fully human antibodies have minimal immunogenicity and safety profiles. At present, most potential antibody drugs in clinical trials are humanized or fully human. Human antibodies are mostly generated using the phage display method (in vitro) or by transgenic mice (in vivo); other methods include B lymphocyte immortalization, human–human hybridoma, and single-cell polymerase chain reaction. Here, we describe a structure-based computer-aided de novo design technology for human antibody generation. Based on the complex structure of human epidermal growth factor receptor 2 (HER2)/Herceptin, we first designed six short peptides targeting the potential epitope of HER2 recognized by Herceptin. Next, these peptides were set as complementarity determining regions in a suitable immunoglobulin frame, giving birth to a novel anti-HER2 antibody named “HF,” which possessed higher affinity and more effective anti-tumor activity than Herceptin. Our work offers a useful tool for the quick design and selection of novel human antibodies for basic mechanical research as well as for imaging and clinical applications in immune-related diseases, such as cancer and infectious diseases.  相似文献   
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It is a demanding and time-consuming task to construct the side window mechanism of a car such that the deflections along the seals are minimized. The reason for this is that the window surface S delivered by the stylist, will in general not be movable in a proper way: It is required that the surface tightly moves along the seals. Deflections will necessarily occur no matter how much effort the engineer invests. This article describes how to find a spatial motion that minimizes seal deflection for some given automobile side window surface. Necessary but acceptable modification of the stylist’s surface S is also addressed, as well as the lifting mechanism design. It is argued that our systematic approach offers considerable savings compared to the prevailing trial-and-error approach.  相似文献   
40.
用Gambit软件对双辐射段裂解炉进行几何建模和网格划分,选择计算流体力学软件Fluent的标准k-ε湍流模型、有限速率/涡耗散燃烧模型和P1辐射模型,对裂解炉辐射段和对流段进行数值模拟计算。模拟计算结果表明,裂解辐射段的烟气温度高于烧焦辐射段;在炉管中心面处,裂解辐射段的压力略高于烧焦辐射段,烟气流动的线速度明显大于烧焦辐射段;两个辐射段的炉管管壁温度分布不一致。尽管裂解辐射段的横跨段出口面烟气平均温度高于烧焦辐射段,但高温烟气没有流入烧焦辐射段且流向对流段的烟气温度场随着对流段高度上升逐渐均匀,该计算结果说明了双辐射段裂解炉的裂解/烧焦切换操作是可行的,并可进一步优化双辐射段裂解炉的结构和操作。  相似文献   
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