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Efficient generation of hepatocyte-like cells from human induced pluripotent stem cells 被引量:64
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作者 Zhihua Song Jun Cai +13 位作者 yanxia Liu Dongxin Zhao Jun Yong Shuguang Duo Xijun Song Yushan Guo Yang Zhao Han Qin Xiaolei Yin Chen Wu Jie Che Shichun Lu Mingxiao Ding Hongkui Deng 《Cell Research》 SCIE CAS CSCD 2009年第11期1233-1242,共10页
Human induced pluripotent stem (iPS) cells are similar to embryonic stem (ES) cells, and can proliferate intensively and differentiate into a variety of cell types. However, the hepatic differentiation of human iP... Human induced pluripotent stem (iPS) cells are similar to embryonic stem (ES) cells, and can proliferate intensively and differentiate into a variety of cell types. However, the hepatic differentiation of human iPS cells has not yet been reported. In this report, human iPS cells were induced to differentiate into hepatic cells by a stepwise protocol. The expression of liver cell markers and liver-related functions of the human iPS cell-derived cells were monitored and compared with that of differentiated human ES cells and primary human hepatocytes. Approximately 60% of the differentiated human iPS cells at day 7 expressed hepatic markers alpha fetoprotein and Alb. The differentiated cells at day 21 exhibited liver cell functions including albumin Asecretion, glycogen synthesis, urea production and inducible cytochrome P450 activity. The expression of hepatic markers and fiver-related functions of the iPS cellderived hepatic ceils were comparable to that of the human ES cell-derived hepatic cells. These results show that human iPS cells, which are similar to human ES cells, can be efficiently induced to differentiate into hepatocyte-like cells. 展开更多
关键词 induced pluripotent stem cells IPS DIFFERENTIATION hepatic cells embryonic stem cells
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多级调剖调驱技术效果及剩余油分布 被引量:27
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作者 梁守成 李强 +3 位作者 吕鑫 ZHOU yanxia 曹伟佳 卢祥国 《大庆石油地质与开发》 CAS CSCD 北大核心 2018年第6期108-115,共8页
为治理渤海稠油油藏经长期注水开发形成的优势通道,多级组合深部液流转向技术受到广泛关注。以油藏工程、物理化学和分析化学等为理论指导,以物理模拟为技术手段,以渤海S油田为模拟对象,开展了分级组合深部调剖调驱效果及剩余油分布研... 为治理渤海稠油油藏经长期注水开发形成的优势通道,多级组合深部液流转向技术受到广泛关注。以油藏工程、物理化学和分析化学等为理论指导,以物理模拟为技术手段,以渤海S油田为模拟对象,开展了分级组合深部调剖调驱效果及剩余油分布研究。结果表明:目标油藏储层经长期注水注聚开发,已经形成了大孔道或高渗条带,大孔道治理是改善油田开发效果的前提条件;与聚合物溶液中分子聚集体分布相比较,聚合物微球粒径分布比较集中,具有"堵大不堵小"渗流特性,"强凝胶封堵大孔道+聚合物微球转向中低渗透层调驱"多级调剖调驱技术兼顾了大孔道治理和中低渗透层深部液流转向技术需求,可以取得较好增油降水效果;"行列式"注水开发井网相邻水井不宜同时进行调驱和调剖;剩余油主要分布在中低渗透层、远离主流线的两翼。 展开更多
关键词 渤海油藏 多级组合 调剖调驱 物理模拟 采收率 剩余油分布 机理分析
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Weapon target assignment problem satisfying expected damage probabilities based on ant colony algorithm 被引量:26
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作者 Wang yanxia Qian Longjun Guo Zhi Ma Lifeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第5期939-944,共6页
A weapon target assignment (WTA) model satisfying expected damage probabilities with an ant colony algorithm is proposed. In order to save armament resource and attack the targets effectively, the strategy of the we... A weapon target assignment (WTA) model satisfying expected damage probabilities with an ant colony algorithm is proposed. In order to save armament resource and attack the targets effectively, the strategy of the weapon assignment is that the target with greater threat degree has higher priority to be intercepted. The effect of this WTA model is not maximizing the damage probability but satisfying the whole assignment result. Ant colony algorithm has been successfully used in many fields, especially in combination optimization. The ant colony algorithm for this WTA problem is described by analyzing path selection, pheromone update, and tabu table update. The effectiveness of the model and the algorithm is demonstrated with an example. 展开更多
关键词 weapon target assignment ant colony algorithm optimization.
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Over-expression of WOX1 Leads to Defects in Meristem Development and Polyamine Homeostasis in Arabidopsis 被引量:23
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作者 yanxia Zhang Renhong Wu +3 位作者 Genji Qin Zhangliang Chen Hongya Gu Li-Jia Qu 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2011年第6期493-506,共14页
In plants, the meristem has to maintain a separate population of pluripotent cells that serve two main tasks, i.e., self-maintenance and organ initiation, which are separated spatially in meristem. Prior to our study,... In plants, the meristem has to maintain a separate population of pluripotent cells that serve two main tasks, i.e., self-maintenance and organ initiation, which are separated spatially in meristem. Prior to our study, WUS and WUS.like WOX genes had been reported as essential for the development of the SAM. In this study, the consequences of gain of WOX1 function are described. Here we report the identification of an Arabidopsis gain-of-function mutant woxl-D, in which the expression level of the WOX1 (WUSCHEL HOMEOBOX 1) was elevated and subtle defects in meristem development were observed. The woxl-D mutant phenotype is dwarfed and slightly bushy, with a smaller shoot apex. The woxl-D mutant also produced small and dark green leaves, and exhibited a failure in anther dehiscence and male sterility. Molecular evidences showed that the transcription of the stem cell marker gene CLV3 was down-regulated in the meristem of woxl-D but accumulated in the other regions, i.e., in the root-hypocotyl junction and at the sites for lateral root initiation. The fact that the organ size and cell size in leaves of woxl-D are smaller than those in wild type suggests that cell expansion is possibly affected in order to have partially retarded the development of lateral organs, possibly through alteration of CLV3 expression pattern in the meristem. An S-adenosylmethionine decarboxylase (SAMDC) protein, SAMDC1, was found able to interact with WOX1 by yeast two-hybrid and pull-down assays in vitro. HPLC analysis revealed a significant reduction of polyamine content in woxl-D. Our results suggest that WOX1 plays an important role in meristem development in Arabidopsis, possibly via regulation of SAMDC activity and polyamine homeostasis, and/or by regulating CLV3 expression. 展开更多
关键词 WOX CLV3 MERISTEMS polyamines SAMDC Arabidopsis.
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抗冻蛋白对预发酵冷冻面团中蛋白质特性及水分状态的影响 被引量:19
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作者 姬成宇 石媛媛 +3 位作者 李梦琴 张剑 安艳霞 艾羽函 《食品科学》 EI CAS CSCD 北大核心 2018年第12期53-59,共7页
采用Ellman’s试剂比色法、十二烷基硫酸钠-聚丙烯酰胺凝胶电泳技术、傅里叶变换红外光谱技术以及核磁共振技术,研究冻藏和冻融循环条件下抗冻蛋白对冷冻面团的蛋白质特性以及水分子存在状态的影响。结果表明:经过冻藏和冻融循环,冷冻... 采用Ellman’s试剂比色法、十二烷基硫酸钠-聚丙烯酰胺凝胶电泳技术、傅里叶变换红外光谱技术以及核磁共振技术,研究冻藏和冻融循环条件下抗冻蛋白对冷冻面团的蛋白质特性以及水分子存在状态的影响。结果表明:经过冻藏和冻融循环,冷冻面团中游离巯基含量上升,二硫键含量下降。添加抗冻蛋白对冷冻面团亚基无影响。随着冻藏时间的延长,二级结构中分子间β-折叠含量增大,β-转角含量减小,而冻融循环使得α-螺旋结构含量下降,添加抗冻蛋白组的蛋白质特性变化均小于无添加组。无添加抗冻蛋白冷冻面团的失水率明显升高,驰豫时间随冻藏时间的延长逐渐变大,结合水含量减少,表明抗冻蛋白能够抑制二硫键的断裂和二级结构的变化,减少冰晶的重结晶,防止面团的水分散失,维持面团的持水能力。 展开更多
关键词 冷冻面团 抗冻蛋白 冻藏和冻融循环 蛋白质结构
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Porous LiF layer fabricated by a facile chemical method toward dendrite-free lithium metal anode 被引量:18
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作者 yanxia Yuan Feng Wu +2 位作者 Guanghai Chen Ying Bai Chuan Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第10期197-203,共7页
Lithium metal is supposed to be critical material for constructing next-generation batteries due to extremely high capacity and ultralow redox potential. However, the perplexing issue of lithium dendrite growth impede... Lithium metal is supposed to be critical material for constructing next-generation batteries due to extremely high capacity and ultralow redox potential. However, the perplexing issue of lithium dendrite growth impedes the commercial application. The initial nucleation and low Li ions diffusion rate in the electrolyte/electrode interface dominate the deposition behavior. Therefore, a uniform and flexible interface is urgently needed. Here, a facile method is proposed to prepare a thin and porous LiF-rich layer (TPL) by the in-situ reaction of small amount of ammonium hydrogen difluoride (NH4HF2) and Li metal. The deposition morphology on Li metal anode with LiF layer is significantly flat and homogeneous owning to low lateral diffusion barrier on LiF crystals and the porous structure of TPL film. Additionally, the symmetrical cells made with such TPL Li anodes show significantly stable cycling over 100 cycles at high current density of 6 mA/cm^2. The TPL Li|LiFePO4 full cells keep over 99% capacity retention after 100 cycles at 2.0 C. This approach serves as a facile and controllable way of adjusting the protective layer on Li metal. 展开更多
关键词 LITHIUM metal anode POROUS LIF LAYER LITHIUM DENDRITE Artificial SEI
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Numerical simulation of leading edge cavitation within the whole flow passage of a centrifugal pump 被引量:15
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作者 LI XiaoJun YUAN ShouQi +2 位作者 PAN ZhongYong YUAN JianPing FU yanxia 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第9期2156-2162,共7页
In this paper, the periodically unsteady pressure field and head-drop phenomenon caused by leading edge cavitation have been investigated numerically by computational fluid dynamics (CFD) in a single stage centrifug... In this paper, the periodically unsteady pressure field and head-drop phenomenon caused by leading edge cavitation have been investigated numerically by computational fluid dynamics (CFD) in a single stage centrifugal pump. A CFD model for cavita- tion steady and unsteady simulation has been calculated using the κ-ω SST turbulence model combining with a multiphase ap- proach, based on a homogeneous model assumption. A truncated form of Rayleigh-Plesset equation is used as a source term for the inter-phase mass transfer. The CFD computational region includes the suction cone, impeller, side chambers and volute, as well as suction and pressure pipes. The results were compared with experimental data under non-cavitation and cavitation conditions and a good agreement was obtained for the global performance, the experimental data of the head and the efficiency are 34.04 m and 74.42% at BEP, respectively, the predicted head is 34.31 m and the predicted efficiency is 73.75%. The analy- sis of inner flow pattern shows that the vortex flow generation in the rear of cavity region is the main reason of the head-drop. Obvious increasing can be observed for the amplitude of the pressure fluctuation at the blade passing frequency with different cavitation situations, and subpeak can be found. Besides, the effects of unsteady flow in the side chambers cannot be neglected for accurately predicting the inner flow of the pump. These results imply that this numerical method is suitable for the cavitat- ing flow in the pump. 展开更多
关键词 centrifugal pump whole flow field leading edge cavitation turbulence kinetic energy pressure fluctuation
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麦麸粉对冷冻发酵面团中蛋白特性和淀粉特性的影响 被引量:14
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作者 艾羽函 姬成宇 +3 位作者 张剑 安艳霞 郭梦园 李梦琴 《河南农业大学学报》 CAS CSCD 北大核心 2018年第5期809-817,共9页
将麦麸粉以5%质量分数添加至面粉中制备适合于馒头生产的冷冻发酵面团,研究不同冻藏时间下麦麸粉对面团中面筋蛋白微观结构变化的影响,分析添加麦麸粉的冷冻发酵面团经过不同时间储存后对其淀粉特性的影响,探讨麦麸添加量、淀粉糊化及... 将麦麸粉以5%质量分数添加至面粉中制备适合于馒头生产的冷冻发酵面团,研究不同冻藏时间下麦麸粉对面团中面筋蛋白微观结构变化的影响,分析添加麦麸粉的冷冻发酵面团经过不同时间储存后对其淀粉特性的影响,探讨麦麸添加量、淀粉糊化及热力学特性和冷冻面团中面筋蛋白微观结构变化之间的相关性。结果表明,添加组冷冻面团中淀粉的峰值黏度、稀懈值、终值黏度和回生值均高于空白组,淀粉的糊化初始温度、峰值温度和终止温度均低于空白对照组;随着冻藏时间的延长,冷冻面团中游离巯基呈现上升趋势,二硫键呈现下降趋势;添加组冷冻面团自旋-自旋弛豫时间T_(21)略高于空白对照组,而T_(22)低于空白对照组;空白对照组分子间β-折叠、反向平行β-折叠和β-折叠比例要高于添加组,而无规则卷曲、α-螺旋和β-转角比例则相反。麦麸粉的添加能够适当地降低冻藏条件下面团中水分的流动,提高冷冻面团的稳定性,抑制面筋蛋白二级结构的变化,升高糊化焓值,使淀粉糊化更彻底,有利于改善面团品质。 展开更多
关键词 麦麸粉 冷冻面团 淀粉特性 蛋白质微观结构 冻藏
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Vitamin C alleviates aging defects in a stem cell model for Werner syndrome 被引量:12
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作者 Ying Li Weizhou Zhang +13 位作者 Liang Chang Yan Han Liang Sun Xiaojun Gong Hong Tang Zunpeng Liu Huichao Deng yanxia Ye Yu Wang Jian Li Jie Qiao Jing Qu Weiqi Zhang Guang-Hui Liu 《Protein & Cell》 SCIE CAS CSCD 2016年第7期478-488,共11页
Werner syndrome (WS) is a premature aging disorder that mainly affects tissues derived from mesoderm. We have recently developed a novel human WS model using WRN-deficient human mesenchymal stem cells (MSCs). This... Werner syndrome (WS) is a premature aging disorder that mainly affects tissues derived from mesoderm. We have recently developed a novel human WS model using WRN-deficient human mesenchymal stem cells (MSCs). This model recapitulates many phenotypic features of WS. Based on a screen of a number of chemicals, here we found that Vitamin C exerts most efficient rescue for many features in premature aging as shown in WRN-deficient MSCs, including cell growth arrest, increased reactive oxygen species levels, teiomere attrition, excessive secretion of inflammatory factors, as well as disorganization of nuclear lamina and heterochromatin. Moreover, Vitamin C restores in vivo viability of MSCs in a mouse model. RNA sequencing analysis indicates that Vitamin C alters the expression of a series of genes involved in chromatin condensation, cell cycle regulation, DNA replication, and DNA damage repair pathways in WRN- deficient MSCs. Our results identify Vitamin C as a rejuvenating factor for WS MSCs, which holds the potential of being applied as a novel type of treatment of WS. 展开更多
关键词 Vitamin C stem cell AGING Wernersyndrome
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A human circulating immune cell landscape in aging and COVID-19 被引量:12
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作者 Yingfeng Zheng Xiuxing Liu +19 位作者 Wenqing Le Lihui Xie He Li Wen Wen Si Wang Shuai Ma Zhaohao Huang Jinguo Ye Wen Shi yanxia Ye Zunpeng Liu Moshi Song Weiqi Zhang Jing-Dong J.Han Juan Carlos lzpisua Belmonte Chuanle Xiao Jing Qu Hongyang Wang Guang-Hui Liu Wenru Su 《Protein & Cell》 SCIE CAS CSCD 2020年第10期740-770,共31页
Age-associated changes in immune cells have been linked to an increased risk for infection.However,a global and detailed characterization of the changes that human circulating immune cells undergo with age is lacking.... Age-associated changes in immune cells have been linked to an increased risk for infection.However,a global and detailed characterization of the changes that human circulating immune cells undergo with age is lacking.Here,we combined scRNA-seq,mass cytometry and sCATAC-seq to compare immune cell types in peripheral blood collected from young and old subjects and patients with COVID-19.We found that the immune cell landscape was reprogrammed with age and was characterized by T cell polarization from naive and memory cells to effector,cytotoxic,exhausted and reg-ulatory cells,along with increased late natural killer cells,age-associated B cells,inflammatory monocytes and age-associated dendritic cells.In addition,the expression of genes,which were implicated in coron-avirus susceptibility,was upregulated in a cell subtype-specific manner with age.Notably,COVID-19 promoted age-induced immune cell polarization and gene expression related to inflammation and cellular senes-cence.Therefore,these findings suggest that a dysreg-ulated immune system and increased gene expression associated with SARS-CoV-2 susceptibility may at least partially account for COVID-19 vulnerability in the elderly. 展开更多
关键词 AGING single-cell sequencing BLOOD COVID-19 immune cells
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Evaluating and Improving Wind Forecasts over South China: The Role of Orographic Parameterization in the GRAPES Model 被引量:12
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作者 Shuixin ZHONG Zitong CHEN +1 位作者 Daosheng XU yanxia ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第6期713-722,共10页
Unresolved small-scale orographic(SSO) drags are parameterized in a regional model based on the Global/Regional Assimilation and Prediction System for the Tropical Mesoscale Model(GRAPES TMM). The SSO drags are re... Unresolved small-scale orographic(SSO) drags are parameterized in a regional model based on the Global/Regional Assimilation and Prediction System for the Tropical Mesoscale Model(GRAPES TMM). The SSO drags are represented by adding a sink term in the momentum equations. The maximum height of the mountain within the grid box is adopted in the SSO parameterization(SSOP) scheme as compensation for the drag. The effects of the unresolved topography are parameterized as the feedbacks to the momentum tendencies on the first model level in planetary boundary layer(PBL)parameterization. The SSOP scheme has been implemented and coupled with the PBL parameterization scheme within the model physics package. A monthly simulation is designed to examine the performance of the SSOP scheme over the complex terrain areas located in the southwest of Guangdong. The verification results show that the surface wind speed bias has been much alleviated by adopting the SSOP scheme, in addition to reduction of the wind bias in the lower troposphere. The target verification over Xinyi shows that the simulations with the SSOP scheme provide improved wind estimation over the complex regions in the southwest of Guangdong. 展开更多
关键词 small-scale orographic drag GRAPES_TMM PBL parameterization wind bias
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Effectiveness of Jinying capsule on pelvic inflammatory disease in patients with symptom pattern of damp and heat accumulation: a double-blinded, multicenter, randomized, placebo-controlled clinical trial 被引量:11
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作者 Yang Yan Lu Yao +7 位作者 Zhou Deping Pei Fenglan Li Qin Chen Shuqiong Wang Qiufeng Wang Yanting Jin Zhe Liu yanxia 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2020年第3期432-439,共8页
OBJECTIVE: To evaluate the therapeutic effectiveness and safety of Jinying capsule on pelvic inflammatory disease(PID) in patients with symptoms identified as the pattern of damp and heat accumulation in terms of Trad... OBJECTIVE: To evaluate the therapeutic effectiveness and safety of Jinying capsule on pelvic inflammatory disease(PID) in patients with symptoms identified as the pattern of damp and heat accumulation in terms of Traditional Chinese Medicine(TCM).METHODS: We conducted a double-blinded, multicenter, randomized, placebo-controlled clinical trial which included 155 patients diagnosed with PID and identified as symptom pattern of damp and heat accumulation. They were randomly divided into experimental group(n = 78) and control group(n = 77) according to a random number table. The treatment lasted for a period of 28 d. The experimental group was given Jinying capsules and oral levofloxacin plus oral metronidazole for first 7 d.They continued with Jinying capsules and levofloxacin placebo and metronidazole placebo for another 7 d. For the remaining 14 d, they continued with Jinying capsules only. Whereas, the control group was treated with oral levofloxacin and metronidazole and Jinying capsule placebo for the first 14 d in the same way as the experimental group and then continued with Jinying capsule placebo only for the remaining 14 d. The clinical efficacy was assessed using McCormack scale, TCM symptom pattern scores, physicochemical indexes including white blood cell and erythrocyte sedimentation rate, C-reaction protein, smear of vaginal discharge,and pelvic ultrasound.RESULTS: Comparing McCormack scale between both groups after treatment, the difference in curative effect between both groups was significant (P = 0.0269). The cure rate of the experimental group and control group is 76.32% and 59.46% respectively at week 4. Comparing TCM symptom pattern scores between both groups before and after treatment, the differences in total effective rate were both significant(P < 0.05). The curative effect rate of experimental group is 2.63% and 13.70% of the control group at week 1(P = 0.0131), and73.33% of the experimental group and 56.94% of the control group at week 4(P = 0.0369). No significant differences were found 展开更多
关键词 Pelvic inflammatory disease Dampness-heat Therapeutic uses Safety Randomized controlled trial Double-blind method Jinying capsule
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Engineering T cells for immunotherapy of primary human hepatocellular carcinoma 被引量:10
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作者 Leidy DCaraballo Galva Lun Cai +1 位作者 yanxia Shao Yukai He 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2020年第1期1-15,共15页
Liver cancers, majority of which are primary hepatocellular carcinoma(HCC), continue to be on the rise in the world. Furthermore, due to the lack of effective treatments, liver cancer ranks the 4th most common cause o... Liver cancers, majority of which are primary hepatocellular carcinoma(HCC), continue to be on the rise in the world. Furthermore, due to the lack of effective treatments, liver cancer ranks the 4th most common cause of male cancer deaths. Novel therapies are urgently needed. Over the last few years,immunotherapies, especially the checkpoint blockades and adoptive cell therapies of engineered T cells,have demonstrated a great potential for treating malignant tumors including HCC. In this review, we summarize the current ongoing research of antigen-specific immunotherapies including cancer vaccines and adoptive cell therapies for HCC. We briefly discuss the HCC cancer vaccine and then focus on the antigen-specific T cells genetically engineered with the T cell receptor genes(TCRTs) and the chimeric antigen receptor genes(CARTs). We first review the current options of TCRTs and CARTs immunotherapies for HCC, and then analyze the factors and parameters that may help to improve the design of TCRTs and CARTs to enhance their antitumor efficacy and safety. Our goals are to render readers a panoramic view of the current stand of HCC immunotherapies and provide some strategies to design better TCRTs and CARTs to achieve more effective and durable antitumor effects. 展开更多
关键词 IMMUNOTHERAPY Hepatocellular carcinoma T CELL RECEPTOR CHIMERIC ANTIGEN RECEPTOR T CELL ENGINEERING Gene transfer
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Developing superior alleles of yield genes in rice by artificial mutagenesis using the CRISPR/Cas9 system 被引量:10
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作者 Liyu Huang Ru Zhang +8 位作者 Guangfu Huang yanxia Li Getachew Melaku Shilai Zhang Haitao Chen Yanjuan Zhao Jing Zhang Yesheng Zhang Fengyi Hu 《The Crop Journal》 SCIE CAS CSCD 2018年第5期475-481,共7页
Rice yield is an important and complex agronomic trait controlled by multiple genes.In recent decades,dozens of yield-associated genes in rice have been cloned,many of which can increase production in the form of loss... Rice yield is an important and complex agronomic trait controlled by multiple genes.In recent decades,dozens of yield-associated genes in rice have been cloned,many of which can increase production in the form of loss or degeneration of function.However,mutations occurring randomly under natural conditions have provided very limited genetic resources for yield increases.In this study,potentially yield-increasing alleles of two genes closely associated with yield were edited artificially.The recently developed CRISPR/Cas9system was used to edit two yield genes:Grain number 1a(Gn1a)and DENSE AND ERECT PANICLE1(DEP1).Several mutants were identified by a target sequence analysis.Phenotypic analysis confirmed one mutant allele of Gn1a and three of DEP1 conferring yield superior to that conferred by other natural high-yield alleles.Our results demonstrate that favorable alleles of the Gnla and DEP1 genes,which are considered key factors in rice yield increases,could be developed by artificial mutagenesis using genome editing technology. 展开更多
关键词 RICE CRISPR/Cas9 Gn1a DEP1 Gene EDITING
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深度共熔溶剂预处理木质纤维素生物质研究进展 被引量:10
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作者 董艳梅 安艳霞 +2 位作者 马阳阳 张剑 李梦琴 《化工进展》 EI CAS CSCD 北大核心 2021年第3期1594-1603,共10页
木质纤维素生物质转化为生物燃料或化工产品一般需经历预处理、酶解及发酵过程,因其复杂的化学结构,在酶解前通常进行预处理以破坏其致密结构,提高酶与纤维素的可及性。深度共熔溶剂(DES)是一类新型的“绿色”溶剂,具有制备简单、价格... 木质纤维素生物质转化为生物燃料或化工产品一般需经历预处理、酶解及发酵过程,因其复杂的化学结构,在酶解前通常进行预处理以破坏其致密结构,提高酶与纤维素的可及性。深度共熔溶剂(DES)是一类新型的“绿色”溶剂,具有制备简单、价格低廉、性质可调、可生物降解、可循环使用等优势,可有效去除木质素组分,同时保留大部分纤维素,在生物质预处理方面具有巨大的潜力。本文介绍了DES的构成、分类及理化性质,总结了DES预处理对生物质组分的影响,并对预处理效果的影响因素如底物和DES的类型、溶剂黏度、温度、生物载量、微波及超声波辅助工艺和两阶段处理工艺等方面进行分析,探讨了DES和生物的相容性,最后针对DES存在的问题及缺点,提出了理性设计和大规模利用DES的机遇与挑战,本文可为实现生物质的低成本预处理和高价值利用提供新的思路。 展开更多
关键词 木质纤维素生物质 深度共熔溶剂 木质素去除 纤维素结晶度 预处理
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Release of VEGF and BMP9 from injectable alginate based composite hydrogel for treatment of myocardial infarction 被引量:10
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作者 Yong Wu Tianqi Chang +7 位作者 Weiqian Chen Xiaoyu Wang Jingjing Li Yueqiu Chen You Yu Zhenya Shen Qian Yu yanxia Zhang 《Bioactive Materials》 SCIE 2021年第2期520-528,共9页
Myocardial infarction(MI)is one of cardiovascular diseases that pose a serious threat to human health.The pathophysiology of MI is complex and contains several sequential phases including blockage of a coronary artery... Myocardial infarction(MI)is one of cardiovascular diseases that pose a serious threat to human health.The pathophysiology of MI is complex and contains several sequential phases including blockage of a coronary artery,necrosis of myocardial cells,inflammation,and myocardial fibrosis.Aiming at the treatment of different stages of MI,in this work,an injectable alginate based composite hydrogel is developed to load vascular endothelial active factor(VEGF)and silk fibroin(SF)microspheres containing bone morphogenetic protein 9(BMP9)for releasing VEGF and BMP9 to realize their respective functions.The results of in vitro experiments indicate a rapid initial release of VEGF during the first few days and a relatively slow and sustained release of BMP9 for days,facilitating the formation of blood vessels in the early stage and inhibiting myocardial fibrosis in the long-term stage,respectively.Intramyocardial injection of such composite hydrogel into the infarct border zone of mice MI model via multiple points promotes angiogenesis and reduces the infarction size.Taken together,these results indicate that the dual-release of VEGF and BMP9 from the composite hydrogel results in a collaborative effect on the treatment of MI and improvement of heart function,showing a promising potential for cardiac clinical application. 展开更多
关键词 Myocardial infarction Injectable hydrogel Silk fibroin microspheres ANGIOGENESIS Myocardial fibrosis
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Comparative study on skin temperature response to menstruation at acupuncture points in healthy volunteers and primary dysmenorrhea patients 被引量:9
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作者 She Yanfen Ma Liangxiao +7 位作者 Zhu Jiang Qi Conghui Wang yanxia Tang Ling Li Chunhua Yuan Hongwen Liu Yuqi Song Jiashan 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2017年第2期220-228,共9页
OBJECTIVE:To assess skin temperature response to menstruation at acupuncture points in primary dysmenorrhea(PD) patients and healthy volunteers so as to explore acupuncture point specificity in reflecting diseases in ... OBJECTIVE:To assess skin temperature response to menstruation at acupuncture points in primary dysmenorrhea(PD) patients and healthy volunteers so as to explore acupuncture point specificity in reflecting diseases in the light of skin temperature.METHODS:Fifty-two PD patients and 49 healthy volunteers were recruited.Skin temperature measurements were performed with a skin temperature assessment device at 10 points.Absolute difference between skin temperature of the same point on the left and right side is used as main outcome measure.RESULTS:On the first day of menstruation, when menstrual pain attacking in PD patients, a significant increase in skin temperature difference was detected at Taixi(KI 3) compared with the healthy group(P < 0.01).A significant reduction in skin temperature difference was detected at Taixi(KI 3) in the first day of menstruation compared with those values in the third day after menstruation(P < 0.01)in the healthy group.On the third day after menstruation, a significant reduction in skin temperature difference was found at Zhongdu(LR 6) in PD group compared with the healthy group(P < 0.05).No significant differences of skin temperature were detected at other points(P > 0.05).CONCLUSION:The skin temperature difference at menstruation-relevant points in PD patients did not all change significantly more than those in women without PD.Significant difference was only found in Taixi(KI 3), the Yuan-source point of Kidney meridian. 展开更多
关键词 Dysmenorrhea Menstruation Skin temperature Point LR 6(Zhongdu) Point KI 3(Taixi) Kidney meridian Comparative study
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COVID-19 in cancer patients:risk,clinical features,and management 被引量:9
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作者 Cuiwei Liu yanxia Zhao +2 位作者 Derick Okwan-Duodu Reva Basho Xiaojiang Cui 《Cancer Biology & Medicine》 SCIE CAS CSCD 2020年第3期519-527,共9页
A novel coronavirus known as severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has spread across the world,prompting the World Health Organization to declare the coronavirus disease of 2019(COVID-19)a public ... A novel coronavirus known as severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has spread across the world,prompting the World Health Organization to declare the coronavirus disease of 2019(COVID-19)a public health emergency of international concern.Cancer patients are regarded as a highly vulnerable population to SARS-CoV-2 infection and development of more severe COVID-19 symptoms,which is possibly due to the systemic immunosuppressive state caused directly by tumor growth and indirectly by effects of anticancer treatment.Currently,much effort has been directed toward studying the pathogenesis and treatment of COVID-19,but the risk profiles,prognoses,and treatment outcomes in cancer patients remain unclear.Based on the current literature,we summarize the risk profiles,clinical and biochemical characteristics,and therapy outcomes of COVID-19 infections in cancer patients.The challenges in the clinical care of cancer patients with COVID-19 are discussed.The goal of this review is to stimulate research to better understand the biological impact and prognoses of COVID-19 infections in cancer patients,thus facilitating improvement of the clinical management of these patients. 展开更多
关键词 Anti-viral therapy anti-cancer treatment COVID-19 IMMUNOTHERAPY INFLAMMATION SARS-CoV-2
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Changes of Accumulated Temperature, Growing Season and Precipitation in the North China Plain from 1961 to 2009 被引量:9
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作者 SONG Yanling ZHAO yanxia WANG Chunyi 《Acta meteorologica Sinica》 SCIE 2011年第4期534-543,共10页
Using the high-quality observed meteorological data, changes of the thermal conditions and precipitation over the North China Plain from 1961 to 2009 were examined. Trends of accumulated temperature and negative tempe... Using the high-quality observed meteorological data, changes of the thermal conditions and precipitation over the North China Plain from 1961 to 2009 were examined. Trends of accumulated temperature and negative temperature, growing season duration, as well as seasonal and annual rainfalls at 48 stations were analyzed. The results show that the accumulated temperature increased significantly by 348.5℃ day due to global warming during 1961-2009 while the absolute accumulated negative temperature decreased apparently by 175.3℃ day. The start of growing season displayed a significant negative trend of -14.3 days during 1961- 2009, but the end of growing season delayed insignificantly by 6.7 days. As a result, the length of growing season increased by 21.0 days. The annual and autumn rainfalls decreased slightly while summer rainfall and summer rainy days decreased significantly. In contrast, spring rainfall increased slightly without significant trends. All the results indicate that the thermal conditions were improved to benefit the crop growth over the North China Plain during 1961-2009, and the decreasing annual and summer rainfalls had no direct negative impact on the crop growth. But the decreasing summer rainfall was likely to influence the water resources in North China, especially the underground water, reservoir water, as well as river runoff, which would have influenced the irrigation of agriculture. 展开更多
关键词 North China Plain AGRICULTURE climate change
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Rational Design of High-Performance PEO/Ceramic Composite Solid Electrolytes for Lithium Metal Batteries 被引量:5
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作者 yanxia Su Fei Xu +2 位作者 Xinren Zhang Yuqian Qiu Hongqiang Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第6期155-189,共35页
Composite solid electrolytes(CSEs)with poly(ethylene oxide)(PEO)have become fairly prevalent for fabricating high-performance solid-state lithium metal batteries due to their high Li~+solvating capability,flexible pro... Composite solid electrolytes(CSEs)with poly(ethylene oxide)(PEO)have become fairly prevalent for fabricating high-performance solid-state lithium metal batteries due to their high Li~+solvating capability,flexible processability and low cost.However,unsatisfactory room-temperature ionic conductivity,weak interfacial compatibility and uncontrollable Li dendrite growth seriously hinder their progress.Enormous efforts have been devoted to combining PEO with ceramics either as fillers or major matrix with the rational design of two-phase architecture,spatial distribution and content,which is anticipated to hold the key to increasing ionic conductivity and resolving interfacial compatibility within CSEs and between CSEs/electrodes.Unfortunately,a comprehensive review exclusively discussing the design,preparation and application of PEO/ceramic-based CSEs is largely lacking,in spite of tremendous reviews dealing with a broad spectrum of polymers and ceramics.Consequently,this review targets recent advances in PEO/ceramicbased CSEs,starting with a brief introduction,followed by their ionic conduction mechanism,preparation methods,and then an emphasis on resolving ionic conductivity and interfacial compatibility.Afterward,their applications in solid-state lithium metal batteries with transition metal oxides and sulfur cathodes are summarized.Finally,a summary and outlook on existing challenges and future research directions are proposed. 展开更多
关键词 Composite solid electrolytes Ionic conductivity Interfacial compatibility Ion conduction pathways Li metal batteries
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