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121.
The γ phase Li3VO4 which possesses higher ionic conductivity is more preferable for lithium ion batteries, but it is only stable at high temperature and would convert to low temperature β phase spontaneously when cooling down. Here, the phase control of Li3VO4 to stabilize its γ phase in room temperature is successfully mediated by introducing proper Si‐doping, and for the first time the electrochemical performances of γ‐Li3VO4 is investigated. It is found that pure γ‐Li3VO4 can be obtained in a doping ratio of x = 0.05–0.15 in Li3+xV1?xSixO4 with addition of excess Li source in synthesis design. The doping mechanism and the energy changes are investigated in detail by using the first principle calculations, it reveals that an interstitial Li+ is formed with doping of Si4+ in Li3VO4 to balance the system charge. When served as an anode, the Si‐doped γ‐Li3VO4 shows much smoothed Li+ insertion/extraction and enhanced cycle stability with only a single pair of redox peaks, which behaves much different with the complex multicouples of redox peaks in typical β‐Li3VO4. These changes in electrochemical performances implies that γ‐Li3VO4 can effectively accommodate Li+ in an easier and more facile way and relieved structure stress during the charge/discharge process.  相似文献   
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Wang  Dongmei  Wang  Bei  Liu  Yumei  Dong  Xiaohui  Su  Yanwei  Li  Sanqiang 《Neurochemical research》2019,44(11):2460-2469
Neurochemical Research - Chemotherapy-related cognitive impairment (CRCI) is a potential long-term side effect during cancer treatment. There are currently no effective treatments for CRCI....  相似文献   
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To investigate the differentiation potential of purified CD90+ cells sorted from adipose-derived stem cells (ADSCs), CD90+ cells were sorted from rabbit ADSCs using flow cytometry. Then, cell expansion of CD90+ cells and unsorted ADSCs was observed using an inverted microscope. Furthermore, cell surface markers including CD40, CD105, and CD90 on CD90+ cells and unsorted ADSCs were quantified using flow cytometry. Additionally, multi-lineage differentiation ability between CD90+ cells and unsorted ADSCs was compared, and expression of adipocyte-related genes PPAR-r and CEBPA as well as stem cell-related gene SOX2 in CD90+ cells and unsorted ADSCs was determined using real-time quantitative PCR. We found that CD90+ cells had a stronger cell proliferation ability than unsorted ADSCs. CD90+ cells showed a stronger ability of osteoblast and chondrocyte differentiation than unsorted ADSCs and CD90? cells, whereas the adipose differentiation ability of CD90+ cells was similar to that of ADSCs and CD90? cells. CD14, CD105, and CD90 on CD90+ cells were expressed more highly than those on ADSCs. Additionally, the mRNA expression level of SOX2 in CD90+ cells was significantly higher than that in ADSCs, whereas the expression of PPAR-r and CEBPA was markedly lower than that in ADSCs. These results suggested that the purified CD90+ cells sorted from ADSCs exhibit a stronger differentiation potential than the unsorted ADSCs.  相似文献   
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B cells played an important role in Schistosoma infection-induced diseases. TLR7 is an intracellular member of the innate immune receptor. The role of TLR7 on B cells mediated immune response is still unclear. Here, C57BL/6 mice were percutaneously infected by S. japonicum for 5–6 weeks. The percentages and numbers of B cells increased in the infected mice (p < 0.05), and many activation and function associated molecules were also changed on B cells. More splenic cells of the infected mice expressed TLR7, and B cells were served as the main cell population. Moreover, a lower level of soluble egg antigen (SEA) specific antibody and less activation associated molecules were found on the surface of splenic B cells from S. japonicum infected TLR7 gene knockout (TLR7 KO) mice compared to infected wild type (WT) mice (p < 0.05). Additionally, SEA showed a little higher ability in inducing the activation of B cells from naive WT mice than TLR7 KO mice (p < 0.05). Finally, the effects of TLR7 on B cells are dependent on the activation of NF-κB p65. Altogether, TLR7 was found modulating the splenic B cell responses in S. japonicum infected C57BL/6 mice.  相似文献   
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Although widely applied in treating hematopoietic malignancies, transplantation of hematopoietic stem/progenitor cells (HSPCs) is impeded by HSPC shortage. Whether circulating HSPCs (cHSPCs) in steady-state blood could be used as an alternative source remains largely elusive. Here we develop a three-dimensional culture system (3DCS) including arginine, glycine, aspartate, and a series of factors. Fourteen-day culture of peripheral blood mononuclear cells (PBMNCs) in 3DCS led to 125- and 70-fold increase of the frequency and number of CD34+ cells. Further, 3DCS-expanded cHSPCs exhibited the similar reconstitution rate compared to CD34+ HSPCs in bone marrow. Mechanistically, 3DCS fabricated an immunomodulatory niche, secreting cytokines as TNF to support cHSPC survival and proliferation. Finally, 3DCS could also promote the expansion of cHSPCs in patients who failed in HSPC mobilization. Our 3DCS successfully expands rare cHSPCs, providing an alternative source for the HSPC therapy, particularly for the patients/donors who have failed in HSPC mobilization.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13238-021-00900-4.  相似文献   
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对分布于内蒙古和林格尔(半干旱地区)和阿拉善(强干旱地区)地区的甘蒙锦鸡儿种群水分调节特性和抗逆性进行了比较研究.结果表明,阿拉善种群比和林格尔种群的叶片渗透调节物质含量高、渗透势低、渗透调节能力强,叶片含水量和自由水含量低、束缚水含量和束缚水/自由水比值高,叶水势和气孔导度低,表明阿拉善种群比和林格尔种群有更强的水分调节能力.阿拉善种群丙二醛(MDA)含量大于和林格尔种群,但细胞膜相对透性和超氧自由基含量小于和林格尔种群,表明阿拉善种群自由基清除能力强、细胞膜稳定性高.有效的水分调节能力和较强的抗逆性是甘蒙锦鸡儿适应干旱环境的重要生理基础.  相似文献   
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利用大肠杆菌 BL2 1 (DE3)表达血管内皮细胞生长因子 (VEGF16 5)表达蛋白以包含体形式存在。为了获得有生物活性的蛋白质 ,我们对影响复性的参数 :氧化型、还原型谷胱甘肽比例 ,复性液的 p H值 ,复性时间 ,精氨酸浓度 ,血管内皮细胞生长因子起始浓度进行了较为系统的研究 ,初步获得了具有一定生物活性的 VEGF16 5二聚体蛋白。  相似文献   
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