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基于Tei指数评价蒽环类药物对急性白血病患儿心脏毒性的研究
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作者 陈雪梅 郭品 +3 位作者 钏刘芳 王梓 李雪娇 何文姬 《昆明医科大学学报》 CAS 2024年第2期117-122,共6页
目的应用超声技术监测急性白血病患儿使用蒽环类药物后的心功能,以期得到心功能早期变化的指标。方法按照入组与排除标准选取2018年3月至2020年12月昆明医科大学附属儿童医院白血病患儿,记录其常规心脏超声指标和组织多普勒,并应用TeiS... 目的应用超声技术监测急性白血病患儿使用蒽环类药物后的心功能,以期得到心功能早期变化的指标。方法按照入组与排除标准选取2018年3月至2020年12月昆明医科大学附属儿童医院白血病患儿,记录其常规心脏超声指标和组织多普勒,并应用TeiS、TeiRL、TeiM和TeiT评估心脏收缩功能的变化。结果正常组和用药前实验组常规心脏超声指标中LVEF的均值都在60%以上,FS、SV及EDV均在正常范围,常规指标、TDI和Tei指数无统计学意义(P>0.05);实验组累积剂量为200和250 mg/m^(2)组的TeiM与用药前存在显著差异(P<0.05);200和250 mg/m^(2)组与用药前的TeiRL存在显著差异(P<0.05);200和250 mg/m^(2)组与用药前的TeiT存在显著差异(P<0.05)。结论Tei指数可作为白血病患儿应用蒽环类药物后左右心功能的早期改变较敏感监测指标。 展开更多
关键词 蒽环类药物 心脏毒性 超声心动图 室间隔基底段心肌做功指数 右室侧壁基底心肌做功指数 左心心肌做功指数
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LincRNA AC027700.1在小鼠蜕膜化中的表达研究 被引量:2
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作者 谭丽萍 高茹菲 +4 位作者 尹鑫 陈雪梅 李方方 袁柳 何俊琳 《遗传》 CAS CSCD 北大核心 2022年第2期168-177,共10页
长链非编码RNA(long non-coding RNA,lncRNA)是一类长度大于200 nt、不具有蛋白编码潜能的RNA分子。在细胞生长发育、物质代谢以及疾病等的发生发展过程中起关键调控作用,但在蜕膜化相关领域研究报道较少。为了探究lincRNA AC027700.1... 长链非编码RNA(long non-coding RNA,lncRNA)是一类长度大于200 nt、不具有蛋白编码潜能的RNA分子。在细胞生长发育、物质代谢以及疾病等的发生发展过程中起关键调控作用,但在蜕膜化相关领域研究报道较少。为了探究lincRNA AC027700.1在早孕小鼠子宫内膜中的表达规律,初步探讨AC027700.1在小鼠蜕膜化中的作用,本研究利用qRT-PCR检测AC027700.1在小鼠孕第6 d胚胎着床点及着床旁子宫组织中的表达;构建了假孕小鼠体内人工诱导蜕膜化模型和原代小鼠子宫内膜基质细胞体外诱导蜕膜化模型,qRT-PCR检测AC027700.1在人工诱导蜕膜化的组织和细胞中的表达;通过分离细胞核、细胞质RNA,qRT-PCR检测AC027700.1在胞核和胞质中的相对表达水平;利用GOseq和KOBAS软件对AC027700.1下游靶基因进行GO和KEGG分析。结果表明,AC027700.1在小鼠孕第6 d着床点子宫组织中的表达显著高于着床旁;AC027700.1在成功诱导蜕膜化的子宫内膜组织及细胞中的表达显著高于未诱导的组织及细胞;AC027700.1主要定位于细胞核内;AC027700.1下游靶基因主要富集于自噬通路、细胞周期以及RNA转运等通路。本研究初步揭示了lincRNA AC027700.1可能与早孕子宫内膜蜕膜化有关,但具体作用及调节机制还有待进一步研究。 展开更多
关键词 lincRNA AC027700.1 蜕膜化 子宫内膜 着床
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前噬菌体研究进展 被引量:5
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作者 陈学梅 魏云林 季秀玲 《遗传》 CAS CSCD 北大核心 2021年第3期240-248,共9页
噬菌体是地球上最多的生物实体,一直被认为是细菌的天敌。然而随着基因组学和分子生物学等技术的快速发展,人们发现噬菌体与宿主之间存在微妙而复杂的关系。前噬菌体是指溶原性细菌内存在的整套噬菌体DNA基因组,广泛分布在细菌基因组中... 噬菌体是地球上最多的生物实体,一直被认为是细菌的天敌。然而随着基因组学和分子生物学等技术的快速发展,人们发现噬菌体与宿主之间存在微妙而复杂的关系。前噬菌体是指溶原性细菌内存在的整套噬菌体DNA基因组,广泛分布在细菌基因组中,对调节细菌宿主生理具有重要作用,如参与调节宿主的毒力、影响生物膜形成、赋予宿主免疫力等。有趣的是,前噬菌体可以通过“监听”细菌的群体感应来调节自身的溶原–裂解状态。近年来,一些细菌中由前噬菌体编码的抗CRISPR蛋白的发现引起了人们对前噬菌体研究的关注。因此,对前噬菌体的研究可以为改造宿主和前噬菌体提供基础理论参考。本文对前噬菌体的预测、分布、分类及功能进行了综述,以期为进一步研究噬菌体与宿主间的关系提供基础。 展开更多
关键词 前噬菌体 毒力 抗CRISPR蛋白 溶原转换 群体感应
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Buyang Huanwu Decoction regulates neural stem cell behavior in ischemic brain 被引量:18
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作者 Baiyan Liu Guangxian Cai +1 位作者 Jian Yi xuemei chen 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第25期2336-2342,共7页
The traditional Chinese medicine Buyang Huanwu Decoction has been shown to improve the neu- rological function of patients with stroke. However, the precise mechanisms underlying its effect remain poorly understood. I... The traditional Chinese medicine Buyang Huanwu Decoction has been shown to improve the neu- rological function of patients with stroke. However, the precise mechanisms underlying its effect remain poorly understood. In this study, we established a rat model of cerebral ischemia by middle cerebral artery occlusion and intragastrically administered 5 g/kg Buyang Huanwu Decoction, once per day, for 1, 7, 14 and 28 days after cerebral ischemia. Immunohistochemical staining revealed a number of cells positive for the neural stem cell marker nestin in the cerebral cortex, the subven- tricular zone and the ipsilateral hippocampal dentate gyrus in rat models of cerebral ischemia. Buyang Huanwu Decoction significantly increased the number of cells positive for 5-bromodeoxyuridine (BrdU), a cell proliferation-related marker, microtubule-associated protein-2, a marker of neuronal differentiation, and growth-associated protein 43, a marker of synaptic plasticity in the ischemic rat cerebral regions. The number of positive cells peaked at 14 and 28 days after intragastric administration of Buyang Huanwu Decoction. These findings suggest that Buyang Huanwu Decoction can promote the proliferation and differentiation of neural stem cells and en- hance synaptic plasticity in ischemic rat brain tissue. 展开更多
关键词 neural regeneration traditional Chinese medicine Buyang Huanwu Decoction cerebral ischemia NESTIN BRDU microtubule-associated protein-2 growth-associated protein 43 neural stem cells proliferation differentiation cerebral cortex subventricular zone dentate gyrus grants-supportedpaper NEUROREGENERATION
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Evolution of permafrost in Northeast Chinasince the Late Pleistocene 被引量:5
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作者 HuiJun Jin XiaoLi Chang +6 位作者 DongLiang Luo RuiXia He LanZhi Lu SiZhong Yang DongXin Guo xuemei chen Stuart A.Harris 《Research in Cold and Arid Regions》 CSCD 2016年第4期269-296,共28页
In Northeast China, permafrost advanced and retreated several times under the influences of fluctuating paleo-climatesand paleo-environments since the Late Pleistocene. During the last 60 years, many new data were obt... In Northeast China, permafrost advanced and retreated several times under the influences of fluctuating paleo-climatesand paleo-environments since the Late Pleistocene. During the last 60 years, many new data were obtained and studies wereconducted on the evolution of permafrost in Northeast China, but so far no systematic summary and review have been made.Based on sedimentary sequences, remains of past permafrost, paleo-flora and -fauna records, and dating data, permafrostevolution since the Late Pleistocene has been analyzed and reconstructed in this paper. Paleo-temperatures reconstructedfrom the remains of past permafrost and those from paleo-flora and -fauna are compared, and thus the southern limitof permafrost (SLP) in each climate period is inferred by the relationship of the permafrost distribution and the meanannual air/ground temperatures (MAAT/MAGT). Thus, the evolutionary history of permafrost is here divided into fivestages: (1) the Late Pleistocene (Last Glaciation, or LG) (65 to 10–8.5 ka), the Last Glaciation Maximum (LGM, 21–13 ka)in particular, the coldest period in the latest history with a cooling of about 6~10 °C, characterized by extensive occurrencesof glaciation, flourishing Mammathas-Coelodonta Faunal Complex (MCFC), widespread aeolian deposits, and significantsea level lowering, and permafrost greatly expanded southwards almost to the coastal plains (37°N–41°N); (2) the HoloceneMegathermal Period (HMP, 8.5–7.0 to 4.0–3.0 ka), 3~5 °C warmer than today, permafrost retreated to about 52°N; (3) theLate Holocene Cold Period (Neoglaciation) (4.0–3.0 to 1.0–0.5 ka), a cooling of 1~3 °C, some earlier thawed permafrost wasrefrozen or attached, and the SLP invaded southwards to 46°N; (4) the Little Ice Age (LIA, 500 to 100–150 a), the latestcold period with significant permafrost expansion; and (5) climate warming since the last century, during which NortheastChina has undergone extensive permafrost degradation. The frequent and substantial expansions and retreats of permafrosthave greatly impacted cold-region environments in Northeast China. North of the SLP during the HMP, or in the presentcontinuous permafrost zone, the existing permafrost was largely formed during the LG and was later overlapped by thepermafrost formed in the Neoglaciation. To the south, it was formed in the Neoglaciation. However, many aspects ofpermafrost evolution still await further investigations, such as data integration, numerical reconstruction, and merging ofChinese permafrost history with those of bordering regions as well as collaboration with related disciplines. Of these, studies on the evolution and degradation of permafrost during the past 150 years and its hydrological, ecological, and environmentalimpacts should be prioritized. 展开更多
关键词 Last Glaciation (LG) Holocene Megathermal Period (HMP) Neoglaciation Little Ice Age (LIA) NortheastChina permafrost evolution
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Construction and analysis of a plant transformation binary vector pBDGG harboring a bi-directional promoter fusing dual visible reporter genes 被引量:3
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作者 Chunxiao Zhang Ying Gai +3 位作者 Wenqi Wang Yanyan Zhu xuemei chen Xiangning Jiang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第4期245-249,共5页
The constitutive promoter of cauliflower mosaic virus 35S (CaMV 35S) is a polar unidirectional promoter and is widely used in plant genetic engineering. In the present study, the unidirectional CaMV 35S promoter has... The constitutive promoter of cauliflower mosaic virus 35S (CaMV 35S) is a polar unidirectional promoter and is widely used in plant genetic engineering. In the present study, the unidirectional CaMV 35S promoter has been modified to a bi-directional promoter by fusing its minimal promoter element to the 5' end of CaMV 35S promoter in the opposite orientation. To qualitatively and quantitatively estimate its bi-directional transcriptional function and activity, two visible reporter genes, gusA (13-glucuronidase, GUS) and gfp (green fluorescent protein, GFP), were fused to the two ends of the promoter in bi-orientations ending with NOS terminator sequences, respectively. Stable expression of gusA and gfp genes in transgenic tobacco (Nicotiana tabacum L.) was visulized by histochemically staining for GUS and fluorescence microscopic observation under UV for GFP in transgenic plants. The expression of two reporter genes showed that the constructed bi-directional promoter did have the bi-directional transcriptional function in both expected orientations. The quantitative estimation of GUS and GFP were determined on a HITACHI F1000 Fluorescence Spectrophotometer with various wavelengths of excitation and emission. The GUS activity varied from g to 250 pmol 4-MU/min/mg protein and the GFP content varied from 0.9 to 1.8 μg/ mg protein in various lines of transgenic tobacco plants. Higher GUS activity generally coupled with lower GFP content, and vice versa. 展开更多
关键词 bi-directional promoter gusA gene gfp gene Nicotiana tabacum L. expression
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Microchannel cooling technique for dissipating high heat flux on W/Cu flat-type mock-up for EAST divertor
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作者 Mingxiang LU Le HAN +5 位作者 Qi ZHAO Juncheng QIU Jianhong ZHOU Dinghua HU Nanyu MOU xuemei chen 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第9期134-144,共11页
As an important component of tokamaks,the divertor is mainly responsible for extracting heat and helium ash,and the targets of the divertor need to withstand high heat flux of 10 MW m-2 for steady-state operation.In t... As an important component of tokamaks,the divertor is mainly responsible for extracting heat and helium ash,and the targets of the divertor need to withstand high heat flux of 10 MW m-2 for steady-state operation.In this study,we proposed a new strategy,using microchannel cooling technology to remove high heat load on the targets of the divertor.The results demonstrated that the microchannel-based W/Cu flat-type mock-up successfully withstood the thermal fatigue test of 1000 cycles at 10 MW m^(-2)with cooling water of 26 l min^(-1),30°C(inlet),0.8 MPa(inlet),15 s power on and 15 s dwell time;the maximum temperature on the heat-loaded surface(W surface)of the mock-up was 493°C,which is much lower than the recrystallization temperature of W(1200°C).Moreover,no occurrence of macrocrack and‘hot spot’at the W surface,as well as no detachment of W/Cu tiles were observed during the thermal fatigue testing.These results indicate that microchannel cooling technology is an efflcient method for removing the heat load of the divertor at a low flow rate.The present study offers a promising solution to replace the monoblock design for the EAST divertor. 展开更多
关键词 MICROCHANNEL DIVERTOR flat-type high heat flux test EAST
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Decision-Making Models Based on Meta-Reinforcement Learning for Intelligent Vehicles at Urban Intersections
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作者 xuemei chen Jiahe Liu +3 位作者 Zijia Wang Xintong Han Yufan Sun Xuelong Zheng 《Journal of Beijing Institute of Technology》 EI CAS 2022年第4期327-339,共13页
Behavioral decision-making at urban intersections is one of the primary difficulties currently impeding the development of intelligent vehicle technology.The problem is that existing decision-making algorithms cannot ... Behavioral decision-making at urban intersections is one of the primary difficulties currently impeding the development of intelligent vehicle technology.The problem is that existing decision-making algorithms cannot effectively deal with complex random scenarios at urban intersections.To deal with this,a deep deterministic policy gradient(DDPG)decision-making algorithm(T-DDPG)based on a time-series Markov decision process(T-MDP)was developed,where the state was extended to collect observations from several consecutive frames.Experiments found that T-DDPG performed better in terms of convergence and generalizability in complex intersection scenarios than a traditional DDPG algorithm.Furthermore,model-agnostic meta-learning(MAML)was incorporated into the T-DDPG algorithm to improve the training method,leading to a decision algorithm(T-MAML-DDPG)based on a secondary gradient.Simulation experiments of intersection scenarios were carried out on the Gym-Carla platform to verify and compare the decision models.The results showed that T-MAML-DDPG was able to easily deal with the random states of complex intersection scenarios,which could improve traffic safety and efficiency.The above decision-making models based on meta-reinforcement learning are significant for enhancing the decision-making ability of intelligent vehicles at urban intersections. 展开更多
关键词 DECISION-MAKING intelligent vehicles meta learning reinforcement learning urban intersections
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Investigation on the Resources of Paris Polyphylla var.yunnanensis
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作者 Shicai WU Guo LI +5 位作者 Qiping WANG Wenli YANG xuemei chen Jian FENG Ganghua LI Shaoshan ZHANG 《Medicinal Plant》 CAS 2020年第6期27-30,共4页
In this study,the resource distribution,morphological characteristics,artificial cultivation and market circulation of Paris Polyphylla var.yunnanensis and its polygerm varieties in Yunnan were investigated by referri... In this study,the resource distribution,morphological characteristics,artificial cultivation and market circulation of Paris Polyphylla var.yunnanensis and its polygerm varieties in Yunnan were investigated by referring to the research literature,field investigation and our planting experience.It is found that P.polyphylla var.yunnanensis is widely distributed in Yunnan Province,realizing large-scale artificial cultivation,while the wild resources of polygerm varieties are almost on the verge of extinction and are in urgent need of protection. 展开更多
关键词 Paris Polyphylla var.yunnanensis Resource distribution CULTIVATION INVESTIGATION
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Optimization of Temperature Drop Formula for Annular Gathering Pipeline in High Water Cut Oil Region of Central Hebei Province
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作者 Haonan Cai Lining Zhao +5 位作者 xuemei chen Xintong chen Tong Guan Jinxiu Wang Bolin Lv Shuaibin Li 《Journal of Power and Energy Engineering》 2018年第9期21-26,共6页
In order to respond to the national policy of energy saving and consumption reduction, the temperature drop formula of annular pipeline should be established to optimize the water mixing temperature and water mixing f... In order to respond to the national policy of energy saving and consumption reduction, the temperature drop formula of annular pipeline should be established to optimize the water mixing temperature and water mixing flow. The traditional temperature drop formula applies the high water cut actual situation to 13.7%. On the basis of the traditional Schulhof temperature drop formula, the influence of hydraulic friction on the oil flow temperature is calculated by the calculus idea. The heat transfer coefficient of the pipeline under the complex condition is obtained by the inverse algorithm, and the water mixing flow and water temperature are simulated with MATLAB. The function surface diagram of the degree and the back station temperature. The actual error can be reduced to 4.8%, and the return station temperature can be optimized by 7 degrees. 展开更多
关键词 Circular Water COLLECTING Oil Hydraulic Friction INVERSE Algorithm SAVING Energy Cost
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The Application of Task-based Approach to Senior High School English Teaching
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作者 xuemei chen 《Journal of Zhouyi Research》 2014年第4期19-22,共4页
关键词 任务教学法 英语教学 应用 高中 青少年学生 教学方法 教学过程 教学模式
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不同基底动脉弯曲度对急性基底动脉闭塞患者取栓治疗的影响
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作者 陈雪梅 潘晓虎 +5 位作者 杨明刚 刘邦勇 曹月洲 贾振宇 赵林波 刘圣 《中华脑科疾病与康复杂志(电子版)》 2024年第2期93-99,共7页
目的探讨不同基底动脉弯曲度(BL)对急性基底动脉闭塞(ABAO)患者取栓治疗的影响。方法回顾性分析盱眙县人民医院神经内科及江苏省人民医院介入放射科自2018年1月至2021年12月收治的110例ABAO患者的临床及影像资料。根据DSA图像上基底动脉... 目的探讨不同基底动脉弯曲度(BL)对急性基底动脉闭塞(ABAO)患者取栓治疗的影响。方法回顾性分析盱眙县人民医院神经内科及江苏省人民医院介入放射科自2018年1月至2021年12月收治的110例ABAO患者的临床及影像资料。根据DSA图像上基底动脉的BL,将110例患者分为非重度弯曲组(0~2级,60例)和重度弯曲组(3级,50例)。比较2组患者的基线资料、取栓治疗及预后情况,分析基底动脉重度弯曲对取栓治疗的影响。结果2组患者中男性、高血压、高脂血症、术中使用中间导管、大动脉粥样硬化型、心源性栓塞、基底动脉下段闭塞、取栓结合血管成形术占比及基线美国国立卫生研究院卒中量表评分、再通成功(mTICI 2b~3级)率比较,差异均有统计学意义(P<0.05)。多因素Logistic回归分析显示,基底动脉BL(OR=1.315,95%CI:1.017~1.700,P=0.037)、取栓次数(OR=3.167,95%CI:1.626~6.168,P=0.001)是ABAO取栓治疗再通失败的独立危险因素。结论基底动脉重度弯曲对ABAO取栓治疗的症状性颅内出血、病死率、90 d良好预后无影响,但可能导致ABAO取栓治疗再通失败。 展开更多
关键词 急性基底动脉闭塞 基底动脉弯曲度 机械取栓
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Validation of proposed diagnostic criteria for allergic bronchopulmonary aspergillosis
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作者 Runjin Cai Yifei Yang +11 位作者 Huan Ge xuemei chen Xinyue Hu Yuanyuan Jiang Lisha Luo Shuanglinzi Deng Jiale Tang chendong Wu Huan Tang Xiaoxiao Gong Xiaozhao Li Juntao Feng 《Chinese Medical Journal》 SCIE CAS CSCD 2024年第9期1132-1134,共3页
To the Editor:Allergic bronchopulmonary aspergillosis(ABPA)is an allergic lung disease caused by hypersensitivity to antigens from Aspergillus,and it most commonly occurs in patients with asthma or cysticbrosis.[1]The... To the Editor:Allergic bronchopulmonary aspergillosis(ABPA)is an allergic lung disease caused by hypersensitivity to antigens from Aspergillus,and it most commonly occurs in patients with asthma or cysticbrosis.[1]The main clinical characteristics of the disease are those related to elevated serum immunoglubulin(Ig)E level,positive Aspergillus fumigatus(A.fumigatus)specic IgE/IgG,repeated pulmonary inltration,and bronchiectasis.However,due to the lack of unied diagnostic criteria and screening methods,ABPA is always underdiagnosed.In 2021,new diagnostic criteria were proposed for allergic bronchopulmonary mycosis(ABPM)in the Japanese population. 展开更多
关键词 ALLERGIC ELEVATED ASPERGILLOSIS
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miR319-TCPs-TGA9/TGA10/ROXY2 regulatory module controls cell fate specification in early anther development in Arabidopsis
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作者 Jinyuan Tao Zijie Pan +3 位作者 Wenwen Kong Beixin Mo xuemei chen Yu Yu 《Science China(Life Sciences)》 SCIE CAS CSCD 2024年第4期839-842,共4页
Dear Editor,The process of anther development is generally conserved across plant species(Ma,2005).Many protein-coding genes and noncoding RNAs have been identified to participate in early anther development in Arabid... Dear Editor,The process of anther development is generally conserved across plant species(Ma,2005).Many protein-coding genes and noncoding RNAs have been identified to participate in early anther development in Arabidopsis(Walbot and Egger,2016).mi R319 is one of the most ancient and conserved mi RNA families in land plants(Chávez Montes et al.,2014). 展开更多
关键词 ARABIDOPSIS miR319 ANCIENT
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Evaluation of the safety and efficiency of cytotoxic T cell therapy sensitized by tumor antigens original from T-ALL-iPSC in vivo
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作者 Weiran Li Meiling Zhou +4 位作者 Lu Wang Liying Huang xuemei chen Xizhuo Sun Tao Liu 《Cancer Innovation》 2024年第1期50-60,共11页
Background:Since RNA sequencing has shown that induced pluripotent stem cells(iPSCs)share a common antigen profile with tumor cells,cancer vaccines that focus on iPSCs have made promising progress in recent years.Prev... Background:Since RNA sequencing has shown that induced pluripotent stem cells(iPSCs)share a common antigen profile with tumor cells,cancer vaccines that focus on iPSCs have made promising progress in recent years.Previously,we showed that iPSCs derived from leukemic cells of patients with primary T cell acute lymphoblastic leukemia(T-ALL)have a gene expression profile similar to that of T-ALL cell lines.Methods:Mice with T-ALL were treated with dendritic and T(DC-T)cells loaded with intact and complete antigens from T-ALL-derived iPSCs(T-ALL-iPSCs).We evaluated the safety and antitumor efficiency of autologous tumor-derived iPSC antigens by flow cytometry,cytokine release assay,acute toxicity experiments,long-term toxicity experiments,and other methods.Results:Our results indicate that complete tumor antigens from T-ALL-iPSCs could inhibit the growth of inoculated tumors in immunocompromised mice without causing acute and long-term toxicity.Conclusion:T-ALL-iPSC-based treatment is safe and can be used as a potential strategy for leukemia immunotherapy. 展开更多
关键词 adoptive cell therapy drug safety evaluation IPSCS T-ALL
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microRNA biogenesis and stabilization in plants 被引量:1
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作者 Ye Xu xuemei chen 《Fundamental Research》 CAS CSCD 2023年第5期707-717,共11页
MicroRNAs(miRNAs)are short endogenous non-coding RNAs that regulate gene expression at the posttranscriptional level in a broad range of eukaryotic species.In animals,it is estimated that more than 60%of mammalian gen... MicroRNAs(miRNAs)are short endogenous non-coding RNAs that regulate gene expression at the posttranscriptional level in a broad range of eukaryotic species.In animals,it is estimated that more than 60%of mammalian genes are targets of miRNAs,with miRNAs regulating cellular processes such as differentiation and proliferation.In plants,miRNAs regulate gene expression and play essential roles in diverse biological processes,including growth,development,and stress responses.Arabidopsis mutants with defective miRNA biogenesis are embryo lethal,and abnormal expression of miRNAs can cause severe developmental phenotypes.It is therefore crucial that the homeostasis of miRNAs is tightly regulated.In this review,we summarize the key mechanisms of plant miRNA biogenesis and stabilization.We provide an update on nuclear proteins with functions in miRNA biogenesis and proteins linking miRNA biogenesis to environmental triggers. 展开更多
关键词 MICRORNAS BIOGENESIS Processing AGO1 pri-miRNA
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基于宏基因组分析纳帕海高原湿地微生物及其碳氮代谢多样性 被引量:7
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作者 徐志伟 陈学梅 +2 位作者 魏云林 张琦 季秀玲 《生物工程学报》 CAS CSCD 北大核心 2021年第9期3276-3292,共17页
由于地理位置特殊和生态系统类型的复杂多样性,高原湿地在水源供给、温室气体调节、生物多样性保护等方面具有不可忽视的生态作用。纳帕海高原湿地是特殊的低纬度高海拔湿地类型,目前关于其微生物多样性的研究较少。文中基于宏基因组学... 由于地理位置特殊和生态系统类型的复杂多样性,高原湿地在水源供给、温室气体调节、生物多样性保护等方面具有不可忽视的生态作用。纳帕海高原湿地是特殊的低纬度高海拔湿地类型,目前关于其微生物多样性的研究较少。文中基于宏基因组学方法对纳帕海高原湿地微生物的基因组进行测序,在细菌域中鉴定出184个门、3 262个属、24 260个种;在古菌域中检测到13个门、32个属;在真菌域中共有13个门、47个属。土壤和水体的物种多样性具有明显差异:在门水平上,土壤中酸杆菌门、变形菌门和放线菌门为优势菌门,水体则以变形菌门和拟杆菌门为主。通过宏基因组分析获得纳帕海微生物群落的多样性数据,并对高原湿地中固碳途径和氮代谢途径进行了初步分析。研究表明碳、氮代谢基因丰度较高,湿地微生物固碳途径主要以卡尔文循环、还原性三羧酸循环和3-羟基丙酸循环为主,变形菌门、绿弯菌门、泉古菌门为主要固碳菌群;对于氮循环,水中以固氮和异化硝酸盐还原过程为主,土壤则以硝化和反硝化过程为主,变形菌门、硝化螺旋菌门、疣微菌门、放线菌门、奇古菌门和广古菌门的微生物为氮循环的主要贡献者。本研究揭示的纳帕海高原湿地微生物多样性,为湿地环境的综合治理和保护提供了新的知识。 展开更多
关键词 纳帕海高原湿地 微生物群落 宏基因组学 碳氮代谢 生物多样性
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A Resource for Inactivation of MicroRNAs Using Short Tandem Target Mimic Technology in Model and Crop Plants 被引量:8
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作者 Ting Peng Mengmeng Qiao +26 位作者 Haiping Liu Sachin Teotia Zhanhui Zhang Yafan Zhao Bobo Wang Dongjie Zhao Lina Shi Cui Zhang Brandon Le Kestrel Rogers Chathura Gunasekara Haitang Duan Yiyou Gu Lei Tian Jinfu Nie Jian Qi Fanrong Meng Lan Huang Qinghui chen Zhenlin Wang Jinshan Tang Xiaoqing Tang Ting Lan xuemei chen Hairong Wei Quanzhi Zhao Guiliang Tang 《Molecular Plant》 SCIE CAS CSCD 2018年第11期1400-1417,共18页
microRNAs (miRNAs)are endogenous small non-coding RNAs that bind to mRNAs and target them for cleavage and/or translational repression,leading to gene silencing.We previously developed short tandem target mimic (STTM)... microRNAs (miRNAs)are endogenous small non-coding RNAs that bind to mRNAs and target them for cleavage and/or translational repression,leading to gene silencing.We previously developed short tandem target mimic (STTM)technology to deactivate endogenous miRNAs in Arabidopsis.Here,we created hundreds of STTMs that target both conserved and species-specific miRNAs in Arabidopsis,tomato,rice,and maize,providing a resource for the functional interrogation of miRNAs.We not only revealed the functions of several miRNAs in plant development,but also demonstrated that tissue-specific inactivation of a few miRNAs in rice leads to an increase in grain size without adversely affecting overall plant growth and development.RNA-seq and small RNAseq analyses of STTM156/157 and STTM165/166 transgenic plants revealed the roles of these miRNAs in plant hormone biosynthesis and activation,secondary metabolism,and ion-channel activity-associated electrophysiology,demonstrating that STTM technology is an effective approach for studying miRNA functions.To facilitate the study and application of STTM transgenic plants and to provide a useful platform for storing and sharing of information about miRNA-regulated gene networks,we have established an online Genome Browser (https://blossom.ffr.mtu.edu/designindex2.php) to display the transcriptomic and miRNAomic changes in STTMinduced miRNA knockdown plants. 展开更多
关键词 SHORT TANDEM TARGET MIMIC (STTM) miRNA RNA-seq Arabidopsis CROP
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Structure development of carbon-based solar-driven water evaporation systems 被引量:13
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作者 Wen He Lei Zhou +3 位作者 Miao Wang Yang Cao xuemei chen Xu Hou 《Science Bulletin》 SCIE EI CSCD 2021年第14期1472-1483,M0004,共13页
Pressing need goes ahead for accessing freshwater in insufficient supply countries and regions,which will become a restrictive factor for human development and production.In recent years,solar-driven water evaporation... Pressing need goes ahead for accessing freshwater in insufficient supply countries and regions,which will become a restrictive factor for human development and production.In recent years,solar-driven water evaporation(SDWE)systems have attracted increasing attention for their specialty in no consume conventional energy,pollution-free,and the high purity of fresh water.In particular,carbon-based photothermal conversion materials are preferred light-absorbing material for SDWE systems because of their wide range of spectrum absorption and high photothermal conversion efficiency based on superconjugate effect.Until now,many carbon-based SDWE systems have been reported,and various structures emerged and were designed to enhance light absorption,optimize heat management,and improve the efficient water transport path.In this review,we attempt to give a comprehensive summary and discussions of structure progress of the carbon-based SDWE systems and their working mechanisms,including carbon nanoparticles systems,single-layer photothermal membrane systems,bi-layer structural photothermal systems,porous carbon-based materials systems,and three dimensional(3D)systems.In these systems,the latest 3D systems can expand the light path by allowing light to be reflected multiple times in the microcavity to increase the light absorption rate,and its large heat exchange area can prompt more water to evaporate,which makes them the promising application foreground.We hope our review can spark the probing of underlying principles and inspiring design strategies of these carbonbased SDWE systems,and further guide device optimizations,eventually promoting in extensive practical applications in the future. 展开更多
关键词 Carbon-based evaporator Solar-driven Photothermal conversion Desalination Structure development
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Nature-inspired surface topography: design and function 被引量:5
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作者 XianTong Yan YuanKai Jin +3 位作者 xuemei chen Chao Zhang ChongLei Hao ZuanKai Wang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2020年第2期32-46,共15页
Learning from nature has traditionally and continuously provided important insights to drive a paradigm shift in technology.In particular,recent studies show that many biological organisms exhibit spectacular surface ... Learning from nature has traditionally and continuously provided important insights to drive a paradigm shift in technology.In particular,recent studies show that many biological organisms exhibit spectacular surface topography such as shape,size,spatial organization,periodicity,interconnectivity,and hierarchy to endow them with the capability to adapt dynamically and responsively to a wide range of environments.More excitingly,in a broader perspective,these normally neglected topological features have the potential to fundamentally change the way of how engineering surface works,such as how fluid flows,how heat is transported,and how energy is generated,saved,and converted,to name a few.Thus,the design of nature-inspired surface topography for unique functions will spur new thinking and provide paradigm shift in the development of the new engineering surfaces.In this review,we first present a brief introduction to some insights extracted from nature.Then,we highlight recent progress in designing new surface topographies and demonstrate their applications in emerging areas including thermal-fluid transport,anti-icing,water harvesting,power generation,adhesive control,and soft robotics.Finally,we offer our perspectives on this emerging field,with the aim to stimulate new thinking on the development of next-generation of new materials and devices,and dramatically extend the boundaries of traditional engineering. 展开更多
关键词 natural inspiration BIOMIMETIC surface topography surface engineering unique functions interfacial interaction mechanisms
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