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971.
972.
973.
Li Guo Lin Jia Lulu Luo Xinru Xu Yangyang Xiang Yujie Ren Dekang Ren Lulu Shen Tingming Liang 《International journal of molecular sciences》2022,23(13)
Circular RNAs (circRNAs), a class of new endogenous non-coding RNAs (ncRNAs), are closely related to the carcinogenic process and play a critical role in tumor metastasis. CircRNAs can lay the foundation for tumor metastasis via promoting tumor angiogenesis, make tumor cells gain the ability of migration and invasion by regulating epithelial-mesenchymal transition (EMT), interact with immune cells, cytokines, chemokines, and other non-cellular components in the tumor microenvironment, damage the normal immune function or escape the immunosuppressive network, and further promote cell survival and metastasis. Herein, based on the characteristics and biological functions of circRNA, we elaborated on the effect of circRNA via circRNA-associated competing endogenous RNA (ceRNA) network by acting as miRNA/isomiR sponges on tumor angiogenesis, cancer cell migration and invasion, and interaction with the tumor microenvironment (TME), then explored the potential interactions across different RNAs, and finally discussed the potential clinical value and application as a promising biomarker. These results provide a theoretical basis for the further application of metastasis-related circRNAs in cancer treatment. In summary, we briefly summarize the diverse roles of a circRNA-associated ceRNA network in cancer metastasis and the potential clinical application, especially the interaction of circRNA and miRNA/isomiR, which may complicate the RNA regulatory network and which will contribute to a novel insight into circRNA in the future. 相似文献
974.
Yunhua Yang Adhimoolam Karthikeyan Jinlong Yin Tongtong Jin Rui Ren Fei Fang Han Cai Mengzhuo Liu Dagang Wang Kai Li Haijian Zhi 《International journal of molecular sciences》2022,23(13)
E3-ubiquitin ligases are known to confer abiotic stress responses in plants. In the present study, GmPUB21, a novel U-box E3-ubiquitin ligase-encoding gene, was isolated from soybean and functionally characterized. The expression of GmPUB21, which possesses E3-ubiquitin ligase activity, was found to be significantly up-regulated by drought, salinity, and ABA treatments. The fusion protein GmPUB21-GFP was localized in the cytoplasm, nucleus, and plasma membrane. Transgenic lines of the Nicotiana benthamiana over-expressing GmPUB21 showed more sensitive to osmotic, salinity stress and ABA in seed germination and inhibited mannitol/NaCl-mediated stomatal closure. Moreover, higher reactive oxygen species accumulation was observed in GmPUB21 overexpressing plants after drought and salinity treatment than in wild-type (WT) plants. Contrarily, silencing of GmPUB21 in soybean plants significantly enhanced the tolerance to drought and salinity stresses. Collectively, our results revealed that GmPUB21 negatively regulates the drought and salinity tolerance by increasing the stomatal density and aperture via the ABA signaling pathway. These findings improved our understanding of the role of GmPUB21 under drought and salinity stresses in soybean. 相似文献
975.
混凝土墙材制品干燥收缩性能及有关问题的探讨 总被引:1,自引:0,他引:1
李庆繁 《墙材革新与建筑节能》2006,(3):21-24
本文针对混凝土墙材制品干燥收缩性能的相关指标,以期在澄清基本概念和详细分析美国相关标准规定的基础上,探讨制定较为合理、统一、灵活的技术标准。 相似文献
976.
977.
随着清洁能源的广泛应用,提高输气管道的输送效率成为热点问题,其中降低管输过程中的摩擦阻力至关重要。为探究三角形肋条在输气管道减阻中的应用效果,利用ANSYS-FLUENT软件对光滑管道和肋条管道中的湍流流动进行了数值模拟。结果表明,在近壁区域,肋条管道与光滑管道的速度剖面相差较大,主流区域相差较小,肋条结构的减阻效果主要基于近壁面;肋条结构将漩涡推离壁面,使肋底充满低速流体,降低近壁面处动量交换,减小摩擦阻力;与光滑壁面相比,尺寸为s=h=0.516 5 mm的肋条具有4.38%的减阻效果。 相似文献
978.
韶钢原料场大修改造工程本着投资省,效益高的原则,在满足工艺要求的前提下,优化配置,保证了流程顺畅,功能分区准确明了,总图布局合理,生产环境安全有序;同时充分利用现有设施及场地,尽可能降低投资,实现了快节奏、高效益、低成本运行的目标。 相似文献
979.
Keke Wang Weinan Cheng Zhaozhao Ding Gang Xu Xin Zheng Meirong Li Guozhong Lu Qiang Lu 《材料科学技术学报》2021,63(4):172-181
Localized and sustained osteogenic-angiogenic stimulation to bone defects is critical for effective bone repair.Here,desferrioxamine(DFO)was loaded on silk fibroin nanofibers and blended with hydroxyapatite nanorods(HA),forming injectable DFO-loaded silk fibroin-HA nanocomposite hydrogels.The composite hydrogels remained homogeneous distribution of HA with high ratio(60%)and also higher stiffness than that of pure silk fibroin nanofiber hydrogels,which provided stable osteogenic stimulation niches for tissue regeneration.Without the scarify of injectability,the hydrogels achieved slow delivery of DFO for above 60 days,resulting in suitable angiogenesis in vitro and in vivo and better osteogenesis than DFO-free systems.Compared to previous injectable silk fibroin-HA hydrogels,the introduction of vascularization capacity further stimulated the osteogenic differentiation of stem cells and accelerated new bone formation.Quicker and better bone healing were detected at defect sites after the injection of DFO-loaded nanocomposite hydrogels,indicating the effective synergistic effect of osteogenic and angiogenic cues.This work provides a simple and effective strategy of introducing angiogenic cues to bone matrices.We believe that the injectable nanocomposite hydrogels are suitable for the regeneration of bone tissues. 相似文献
980.
阳离子基团的分布对阴离子交换膜的微观相态和阴离子传导率有显著的影响.为开发全钒液流电池用高性能阴离子交换膜,本文通过向含有二甲胺基团的氟化聚芴醚前驱体接枝含阳离子烷基链的方式,合成了具有相似离子交换容量的一系列侧链多阳离子型氟化聚芴醚.实验结果表明,多阳离子侧链的引入能促进微观相分离的形成并提升阴离子传导率.同时,侧链... 相似文献