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991.
992.
Liu Yang Yan Liu Mingli Yue Ping Li Yulong Liu Fei Ye Ying Fu 《International journal of molecular sciences》2022,23(11)
A new chemosensor, namely N-(2-morpholinoethyl)acetamide-4-morpholine-1,8-naphthimide (MMN), was designed and synthesized through an amidation reaction. MMN was fabricated as a multifunctional fluorescent probe for monitoring pH and isoxaflutole. MMN exhibited excellent stability in MeCN/H2O (v/v, 9/1), with an obvious “off–on” fluorescence response toward pH changes due to intramolecular charge transfer (ICT), where the linear response ranges of MMN in the weakly acidic system were from 4.2 to 5.0 and from 5.0 to 6.0 with apparent pKa = 4.62 ± 0.02 and 5.43 ± 0.02. Based on morpholine as the lysosome targetable unit, MMN could selectively locate lysosomes in live cells. MMN also successfully detected the presence of H+ in test papers. Finally, MMN could specifically recognize isoxaflutole at a detection limit of 0.88 μM. A possible sensing mechanism was identified based on density function theory calculations. These results indicate that MMN could be a superior potential chemosensor for detecting pH and isoxaflutole selectively and sensitively and could be used in real sample detection. 相似文献
993.
994.
Lan Yang Shiqi Huang Zhirong Zhang Zhenmi Liu Ling Zhang 《International journal of molecular sciences》2022,23(11)
Red blood cell-derived extracellular vesicles (RBCEVs) are vesicles naturally produced by red blood cells and play multiple roles such as acting as cell-to-cell communication messengers in both normal physiological and diseased states. RBCEVs are highly promising delivery vehicles for therapeutic agents such as biomolecules and nucleic acids as they are easy to source, safe, and versatile. RBCEVs autonomously target the liver and pass the blood–brain barrier into the brain, which is highly valuable for the treatment of liver and brain diseases. RBCEVs can be modified by various functional units, including various functional molecules and nanoparticles, to improve their active targeting capabilities for tumors or other sites. Moreover, the RBCEV level is significantly shifted in many diseased states; hence, they can also serve as important biomarkers for disease diagnoses. It is clear that RBCEVs have considerable potential in multiple medical applications. In this review, we briefly introduce the biological roles of RBCEVs, presented interesting advances in RBCEV applications, and discuss several challenges that need to be addressed for their clinical translation. 相似文献
995.
根据目前闻喜县秸秆饲料化技术的现状及存在的问题进行了分析研究,并针对农业结构调整和产业化经营发展中的需要,提出了实现秸秆饲料规模化商品生产的技术方案、生产工艺及设备选择. 相似文献
996.
997.
Tianchi Zhou Yaxin Zhang Bo Zhang Hongxin Zeng Zhiyong Tan Xilin Zhang Lan Wang Zhi Chen Juncheng Cao Kaijun Song Ziqiang Yang 《中国通信》2021,(5):221-244
Terahertz communication technology can provide abundant frequency resources,strong confidentiality,antijamming capability,communication tracking capability and ... 相似文献
998.
Jia-Shun Liu Yi-Kun Zhang Hui Tang Li-Bo Zhang Ben-Qiang Yang Ying Yan Li-Min Luo Yang Chen 《核技术(英文版)》2021,32(8):23-33
Tomographic perfusion imaging is a significant imaging modality for stroke diagnosis.However,the low rotational speed of the C-arm(6-8 s per circle)is a chal-le... 相似文献
999.
1000.
Peng Liu Xinyue Wang Qian Yang Xiaolin Yan Yu Fan Si Zhang Yi Wei Min Huang Lingyan Jiang Lu Feng 《International journal of molecular sciences》2022,23(12)
Escherichia coli K1 is a leading cause of neonatal bacterial meningitis. Recruitment of neutrophils to the central nervous system (CNS) via local immune response plays a critical role in defense against E. coli K1 infection; however, the mechanism underlying this recruitment remains unclear. In this study, we report that microglia and astrocytes are activated in response to stimulation by E. coli K1 and/or E. coli K1-derived outer membrane vesicles (OMVs) and work collaboratively to drive neutrophil recruitment to the CNS. Microglial activation results in the release of the pro-inflammatory cytokine TNF-α, which activates astrocytes, resulting in the production of CXCL1, a chemokine critical for recruiting neutrophils. Mice lacking either microglia or TNF-α exhibit impaired production of CXCL1, impaired neutrophil recruitment, and an increased CNS bacterial burden. C-X-C chemokine receptor 2 (CXCR2)-expressing neutrophils primarily respond to CXCL1 released by astrocytes. This study provides further insights into how immune responses drive neutrophil recruitment to the brain to combat E. coli K1 infection. In addition, we show that direct recognition of E. coli K1 by microglia is prevented by the K1 capsule. This study also reveals that OMVs are sufficient to induce microglial activation. 相似文献