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How Plants Cope with Cadmium: Staking All on Metabolism and Gene Expression 被引量:61
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作者 Giovanni DalCorso Silvia Farinati +1 位作者 Silvia Maistri Antonella Furini 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2008年第10期1268-1280,共13页
Environmental pollution is one of the major problems for human health. Toxic heavy metals are normally present as soil constituents or can also be spread out in the environment by human activity and agricultural techn... Environmental pollution is one of the major problems for human health. Toxic heavy metals are normally present as soil constituents or can also be spread out in the environment by human activity and agricultural techniques. Soil contamination by heavy metals as cadmium, highlights two main aspects: on one side they interfere with the life cycle of plants and therefore reduce crop yields, and on the other hand, once adsorbed and accumulated into the plant tissues, they enter the food chain poisoning animals and humans. Considering this point of view, understanding the mechanism by which plants handle heavy metal exposure, in particular cadmium stress, is a primary goal of plant-biotechnology research or plant breeders whose aim is to create plants that are able to recover high amounts of heavy metals, which can be used for phytoremediation, or identify crop varieties that do not accumulate toxic metal in grains or fruits. In this review we focus on the main symptoms of cadmium toxicity both on root apparatus and shoots. We elucidate the mechanisms that plants activate to prevent absorption or to detoxify toxic metal ions, such as synthesis of phytochelatins, metallothioneins and enzymes involved in stress response. Finally we consider new plant-biotechnology applications that can be applied for phytoremediation. 展开更多
关键词 CADMIUM heavy metals METALLOTHIONEINS PHYTOCHELATINS PHYTOREMEDIATION transporters.
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基于CALS及Surpac-FLAC^3D耦合技术的复杂空区稳定性分析 被引量:44
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作者 刘科伟 李夕兵 +2 位作者 宫凤强 刘希灵 王卫华 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2008年第9期1924-1931,共8页
由于受地质条件和探测技术的限制,传统探测方法很难获得复杂空区精确的实际空间分布形状,由此得到的空区用于建立数值分析模型显得过于粗糙,在此基础上进行空区稳定性分析的可靠性程度不高。采用空区激光自动扫描系统(CALS)对复杂空区... 由于受地质条件和探测技术的限制,传统探测方法很难获得复杂空区精确的实际空间分布形状,由此得到的空区用于建立数值分析模型显得过于粗糙,在此基础上进行空区稳定性分析的可靠性程度不高。采用空区激光自动扫描系统(CALS)对复杂空区进行激光扫描,在获得精准三维点云数据的基础上,运用Surpac软件模拟出空区的三维地质模型,通过耦合方法可以在FLAC3D中生成与实际空区空间分布一致的数值模型,提高复杂空区稳定性计算的准确性和可靠性。选取三道庄露天矿的地下空区作为工程实例,利用CALS获得不规则空区的实际空间边界。在此基础上,运用Surpac进行三维块体模拟,研究Surpac与FLAC3D模型耦合技术,成功地将三维模型数据导入FLAC3D中,结合现场实际勘测的围岩力学参数,对空区进行静力计算,分析空区的稳定性。 展开更多
关键词 采矿工程 复杂空区稳定性 空区激光自动扫描系统(CALS) 耦合 数值模拟
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Mesenchymal stromal cells-exosomes:a promising cell-free therapeutic tool for wound healing and cutaneous regeneration 被引量:33
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作者 Peng Hu Qinxin Yang +5 位作者 Qi Wang Chenshuo Shi Dali Wang Ubaldo Armato Ilaria Dal Prà Anna Chiarini 《Burns & Trauma》 SCIE 2019年第1期346-355,共10页
Cutaneous regeneration at the wound site involves several intricate and dynamic processes which require a series of coordinated interactions implicating various cell types,growth factors,extracellular matrix(ECM),nerv... Cutaneous regeneration at the wound site involves several intricate and dynamic processes which require a series of coordinated interactions implicating various cell types,growth factors,extracellular matrix(ECM),nerves,and blood vessels.Mesenchymal stromal cells(MSCs)take part in all the skin wound healing stages playing active and beneficial roles in animal models and humans.Exosomes,which are among the key products MSCs release,mimic the effects of parental MSCs.They can shuttle various effector proteins,messenger RNA(mRNA)and microRNAs(miRNAs)to modulate the activity of recipient cells,playing important roles in wound healing.Moreover,using exosomes avoids many risks associated with cell transplantation.Therefore,as a novel type of cell-free therapy,MSC-exosome-mediated administration may be safer and more efficient than whole cell.In this review,we provide a comprehensive understanding of the latest studies and observations on the role of MSC-exosome therapy in wound healing and cutaneous regeneration.In addition,we address the hypothesis of MSCs microenvironment extracellular vesicles(MSCs-MEVs)or MSCs microenvironment exosomes(MSCs-MExos)that need to take stock of and solved urgently in the related research about MSC-exosomes therapeutic applications.This review can inspire investigators to explore new research directions of MSC-exosome therapy in cutaneous repair and regeneration. 展开更多
关键词 Cutaneous regeneration Mesenchymal stromal cell EXOSOMES Wound healing MICROENVIRONMENT
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基于双尺度自动机模型的植物花序模拟 被引量:18
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作者 赵星 PhilippedeReffye +2 位作者 熊范纶 胡包钢 康孟珍 《计算机学报》 EI CSCD 北大核心 2003年第1期116-124,共9页
花序的模拟是“虚拟植物生长”的重要研究内容 .以往的研究主要集中在怎样应用“L系统”模拟植物花序 .但L系统用字符串表示的产生式具有难以理解和使用的缺点 ,特别是模拟花序的生长和开花顺序时 ,结构复杂且模型参数不易确定 .而“双... 花序的模拟是“虚拟植物生长”的重要研究内容 .以往的研究主要集中在怎样应用“L系统”模拟植物花序 .但L系统用字符串表示的产生式具有难以理解和使用的缺点 ,特别是模拟花序的生长和开花顺序时 ,结构复杂且模型参数不易确定 .而“双尺度自动机模型”是一种基于植物生长机理的植物形态发生模型 .该模型结构简洁明了 ,形象直观 ,易于理解和编程实现 .该文以几种典型花序的模拟为例 ,探讨了应用双尺度自动机模型模拟花序的方法 .通过在双尺度自动机模型中引入“同步生长机制”和“重复生长机制” ,能够模拟所有植物学中给出的花序类型 .并通过应用“生长延时机制” ,实现了“向顶开花”和“向基开花”两种开花顺序的模拟 ,避免了L系统用成花信号控制的缺点 .最后通过与L系统的比较 。 展开更多
关键词 双尺度自动机模型 植物花序 模拟 虚拟植物生长 计算机图形学 计算机模拟
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Obesity leads to higher risk of sperm DNA damage in infertile patients 被引量:29
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作者 Charlotte Dupont Celine Fauret +10 位作者 Nathalie Sermondade Marouane Boubaya Florence Eustache Patrice Clement Pascal Briot Isabelle Berthaut Vincent Levy Isabelle Cedrin-Durnerin Brigitte Benzacken Pascale Chavatte-Palmer Rachel Levy 《Asian Journal of Andrology》 SCIE CAS CSCD 2013年第5期622-625,共4页
There has been a growing interest over the past few years in the impact of male nutrition on fertility. Infertility has been linked to male overweight or obesity, and conventional semen parameter values seem to be alt... There has been a growing interest over the past few years in the impact of male nutrition on fertility. Infertility has been linked to male overweight or obesity, and conventional semen parameter values seem to be altered in case of high body mass index (BMI). A few studies assessing the impact of BMI on sperm DNA integrity have been published, but they did not lead to a strong consensus. Our objective was to explore further the relationship between sperm DNA integrity and BMI, through a 3-year multicentre study. Three hundred and thirty male partners in subfertile couples were included. Using the terminal uridine nick-end labelling (TUNEL) assay, we observed an increased rate of sDerm DNA damage in obese men (odds ratio (95% confidence interval): 2.5 (1.2-5.1)). 展开更多
关键词 male infertility OBESITY OVERWEIGHT SPERM sperm DNA fragmentation
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微通道内气-液传质研究 被引量:23
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作者 乐军 陈光文 +2 位作者 袁权 罗灵爱 LE GALL Hervé 《化工学报》 EI CAS CSCD 北大核心 2006年第6期1296-1303,共8页
以CO2-H2O为模型体系,实验考察了当量直径为667 μm的单通道和16个并行通道内的气-液传质行为.实验发现,液体表观速度增加,单通道内液侧体积传质系数明显提高;同一液体表观速度下,液侧体积传质系数随气体表观速度增加而增加;在实验数据... 以CO2-H2O为模型体系,实验考察了当量直径为667 μm的单通道和16个并行通道内的气-液传质行为.实验发现,液体表观速度增加,单通道内液侧体积传质系数明显提高;同一液体表观速度下,液侧体积传质系数随气体表观速度增加而增加;在实验数据基础上关联了液侧体积传质系数与气-液两相流参数间的关系.微通道内的液侧体积传质系数较常规尺度气-液接触设备至少高1~2个数量级.并讨论了并行微通道内气-液两相流分配特性对整体传质性能的影响,表明合理设计气、液流动分布结构,可保证微通道内优异的传质特性. 展开更多
关键词 微通道 气-液两相流 传质 过程强化
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Therapeutic siRNA:state of the art 被引量:25
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作者 Bo Hu Liping Zhong +4 位作者 Yuhua Weng Ling Peng Yuanyu Huang Yongxiang Zhao Xing-Jie Liang 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2020年第1期1532-1556,共25页
RNA interference(RNAi)is an ancient biological mechanism used to defend against external invasion.It theoretically can silence any disease-related genes in a sequence-specific manner,making small interfering RNA(siRNA... RNA interference(RNAi)is an ancient biological mechanism used to defend against external invasion.It theoretically can silence any disease-related genes in a sequence-specific manner,making small interfering RNA(siRNA)a promising therapeutic modality.After a two-decade journey from its discovery,two approvals of siRNA therapeutics,ONPATTRO®(patisiran)and GIVLAARI™(givosiran),have been achieved by Alnylam Pharmaceuticals.Reviewing the long-term pharmaceutical history of human beings,siRNA therapy currently has set up an extraordinary milestone,as it has already changed and will continue to change the treatment and management of human diseases.It can be administered quarterly,even twice-yearly,to achieve therapeutic effects,which is not the case for small molecules and antibodies.The drug development process was extremely hard,aiming to surmount complex obstacles,such as how to efficiently and safely deliver siRNAs to desired tissues and cells and how to enhance the performance of siRNAs with respect to their activity,stability,specificity and potential off-target effects.In this review,the evolution of siRNA chemical modifications and their biomedical performance are comprehensively reviewed.All clinically explored and commercialized siRNA delivery platforms,including the GalNAc(N-acetylgalactosamine)–siRNA conjugate,and their fundamental design principles are thoroughly discussed.The latest progress in siRNA therapeutic development is also summarized.This review provides a comprehensive view and roadmap for general readers working in the field. 展开更多
关键词 APPROVAL summarized thoroughly
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三倍回波化学位移梯度回波成像与活体^1H-MRS对肝脏脂肪含量定量分析的对照研究 被引量:24
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作者 B.Guiu J.M.Petit +4 位作者 R.Loffroy D.Ben Salem S.Aho D.Masson 范丽 《国际医学放射学杂志》 2009年第2期176-177,共2页
目的 以活体^1H-MRS作为参考标准,评价三倍回波梯度回波序列对肝脏脂肪含量的量化。方法 此前瞻畦研究经伦理委员会批准,且所有病人签署了书面知情同意书。37例2型糖尿病病人(男31例,女6例,平均年龄56岁)采用3.0 T MR设备先对... 目的 以活体^1H-MRS作为参考标准,评价三倍回波梯度回波序列对肝脏脂肪含量的量化。方法 此前瞻畦研究经伦理委员会批准,且所有病人签署了书面知情同意书。37例2型糖尿病病人(男31例,女6例,平均年龄56岁)采用3.0 T MR设备先对肝脏第VII段行单体素^1H-MRS,经T1和T2衰减的校正,通过4.7ppm(1ppm表示10^-6)水峰和1.3ppm甲基计算肝脏脂肪含量。 展开更多
关键词 ^1H-MRS 梯度回波成像 脂肪含量 肝脏 定量分析 化学位移 活体 梯度回波序列
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利用芳香族化合物估测反刍动物采食量的潜力 被引量:15
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作者 龙瑞军 王元素 +2 位作者 董世魁 丁玲玲 J.PAGELLA 《草业学报》 CSCD 2004年第2期13-22,共10页
综述了芳香族化合物的发现过程、反刍动物饲草料、瘤胃和尿液中芳香族化合物的主要类型及存在形式。马尿酸是最早从家畜排泄物中发现的芳香族化合物。反刍动物的尿液中排出的苯甲酸几乎完全来源于日粮中的前体物。饲料日粮中芳香族化合... 综述了芳香族化合物的发现过程、反刍动物饲草料、瘤胃和尿液中芳香族化合物的主要类型及存在形式。马尿酸是最早从家畜排泄物中发现的芳香族化合物。反刍动物的尿液中排出的苯甲酸几乎完全来源于日粮中的前体物。饲料日粮中芳香族化合物是酚酸、简单酚、香豆素、棉子酚、酚的生物碱、类黄酮、单宁酸和木质素。羟基肉桂酸和安息香酸是维管束植物中广泛存在的一类酚类化合物,其在禾本科牧草中的含量远高于豆科牧草,但禾谷类籽实中的含量却很低。瘤胃液和尿液中的芳香族代谢物主要是无酚的芳香酸、酚酸和苯酚,环己烷羧酸是惟一发现的脂环族酸。饲喂不同的日粮饲草料,反刍家畜以马尿酸形式排出的氮量大约占尿氮总量的6%,变化范围为1%~38%。测定尿中芳香族化合物特别是马尿酸对预测反刍家畜的采食量具有重要潜力和作用。 展开更多
关键词 反刍动物 芳香族化合物 饲草料 存在形式和前体物 瘤胃 尿液
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New insights in diabetic foot infection 被引量:19
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作者 Jean-Louis Richard Albert Sotto Jean-Philippe Lavigne 《World Journal of Diabetes》 SCIE CAS 2011年第2期24-32,共9页
Foot ulcers are common in diabetic patients,have a cumulative lifetime incidence rate as high as 25%and frequently become infected.The spread of infection to soft tissue and bone is a major causal factor for lowerlimb... Foot ulcers are common in diabetic patients,have a cumulative lifetime incidence rate as high as 25%and frequently become infected.The spread of infection to soft tissue and bone is a major causal factor for lowerlimb amputation.For this reason,early diagnosis and appropriate treatment are essential,including treatment which is both local(of the foot)and systemic(metabolic),and this requires coordination by a multidisciplinary team.Optimal treatment also often involves extensive surgical debridement and management of the wound base,effective antibiotic therapy,consideration for revascularization and correction of metabolic abnormalities such as hyperglycemia.This article focuses on diagnosis and management of diabetic foot infections in the light of recently published data in order to help clinicians in identification,assessment and antibiotic therapy of diabetic foot infections. 展开更多
关键词 DIABETIC FOOT ULCER INFECTION MANAGEMENT
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程序升温脱附活化能估算新模型 被引量:18
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作者 李湘 李忠 罗灵爱 《化工学报》 EI CAS CSCD 北大核心 2006年第2期258-262,共5页
以吸附过程本征动力学模型为基础,提出了一种新的TPD非线性活化能估算模型.与经典TPD模型相比,这种新的TPD理论模型考虑了脱附过程中存在的吸附质分子再吸附现象的影响,更接近实际的脱附过程.采用TPD实验技术测定了二苯并呋喃在Nor... 以吸附过程本征动力学模型为基础,提出了一种新的TPD非线性活化能估算模型.与经典TPD模型相比,这种新的TPD理论模型考虑了脱附过程中存在的吸附质分子再吸附现象的影响,更接近实际的脱附过程.采用TPD实验技术测定了二苯并呋喃在Norit RB1、Monolith和Chemviron3种活性炭上、不同升温速率下的程序升温脱附图谱.以这些TPD图谱为基础,分别采用经典TPD模型和TPD非线性模型计算了二苯并呋喃在3种活性炭上的脱附活化能.结果表明,经典TPD模型所估算出来的二苯并呋喃的活化能要偏高TPD非线性模型估算结果约8%~12%,脱附过程中存在吸附质分子再吸附现象对脱附活化能有较大的影响. 展开更多
关键词 脱附活化能 程序升温脱附 TPD模型 二苯并呋喃 活性炭
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Selective laser melting(SLM)of CX stainless steel:Theoretical calculation,process optimization and strengthening mechanism 被引量:16
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作者 Dongdong Dong Cheng Chang +7 位作者 Hao Wang Xingchen Yan Wenyou Ma Min Liu Sihao Deng Julien Gardan Rodolphe Bolot Hanlin Liao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第14期151-164,共14页
In the present work,selective laser melting(SLM)technology was utilized for manufacturing CX stainless steel samples under a series of laser parameters.The effect of laser linear energy density on the microstructure c... In the present work,selective laser melting(SLM)technology was utilized for manufacturing CX stainless steel samples under a series of laser parameters.The effect of laser linear energy density on the microstructure characteristics,phase distribution,crystallographic orientation and mechanical properties of these CX stainless steel samples were investigated theoretically and experimentally via scanning electron microscope(SEM),X-ray diffraction(XRD),electron backscatter diffraction(EBSD)and transmission electron microscope(TEM).Based on the systematic study,the SLM CX stainless steel sample with best surface roughness(Ra=4.05±1.8μm)and relative density(Rd=99.72%±0.22%)under the optimal linear density(η=245 J/m)can be obtained.SLM CX stainless steel was primarily constituted by a large number of fine martensite(α’phase)structures(i.e.,cell structures,cellular dendrites and blocky grains)and a small quantity of austenite(γphase)structures.The pre ferred crystallographic orientation(i.e.,<111>direction)can be determined in the XZ plane of the SLM CX sample.Furthermore,under the optimal linear energy density,the good combinations with the highest ultimate tensile strength(UTS=1068.0%±5.9%)and the best total elongation(TE=15.70%±0.26%)of the SLM CX sample can be attained.Dislocation strengthening dominates the strengthening mechanism of the SLM CX sample in as-built state. 展开更多
关键词 Selective laser melting CX stainless steel Forming quality Mechanical property Strengthening MECHANISM
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Liver transplantation for hepatocellular carcinoma: the Hangzhou experience 被引量:16
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作者 Ronald W. Busuttil 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2008年第3期235-236,共2页
Over the last 25 years orthotopic liver transplantation (OLT) has been proven a durabletherapy for all forms of end stage liver
关键词 HCC the Hangzhou experience Liver transplantation for hepatocellular carcinoma
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The IKK-related kinases: from innate immunity to oncogenesis 被引量:16
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作者 Jean-Francois Clément 《Cell Research》 SCIE CAS CSCD 2008年第9期889-899,共11页
Over the past four years, the field of the innate immune response has been highly influenced by the discovery of the IKB kinase (IKK)-related kinases, TANK Binding Kinase I (TBK1) and IKKi, which regulate the acti... Over the past four years, the field of the innate immune response has been highly influenced by the discovery of the IKB kinase (IKK)-related kinases, TANK Binding Kinase I (TBK1) and IKKi, which regulate the activity of interferon regulatory factor (IRF)-3/IRF-7 and NF-κB transcription factors. More recently, additional essential components of the signaling pathways that activate these IKK homologues have been discovered. These include the RNA helicases RIGi and MDA5, and the downstream mitochondrial effector known as CARDIF/MAVS/VISA/IPS-1. In addition to their essential functions in controlling the innate immune response, recent studies have highlighted a role of these kinases in cell proliferation and oncogenesis. The canonical IKKs are well recognized to be a bridge linking chronic inflammation to cancer. New findings now suggest that the IKK-related kinases TBK1 and IKKi also participate in signaling pathways that impact on cell transformation and tumor progression. This review will therefore summarize and discuss the role of TBK1 and IKKi in cellular transformation and oncogenesis by focusing on their regulation and substrate specificity. 展开更多
关键词 cancer IKKi TBK 1 CYTOKINES NF-κB interferon regulatory factor INFLAMMATION
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Albumin liver dialysis as pregnancy-saving procedure in cholestatic liver disease and intractable pruritus 被引量:14
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作者 Maud Lemoine Aurélie Revaux +5 位作者 Claire Francoz Guillaume Ducarme Sabine Brechignac Emmanuel Jacquemin Michèle Uzan Nathalie Ganne-Carrié 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第42期6572-6574,共3页
Progressive familial intrahepatic cholestasis type 3 (PFIC3) is a rare cholestatic liver disease. Such liver disease can get worse by female hormone disorder. Albumin dialysis or Molecular Adsorbent Recirculating Syst... Progressive familial intrahepatic cholestasis type 3 (PFIC3) is a rare cholestatic liver disease. Such liver disease can get worse by female hormone disorder. Albumin dialysis or Molecular Adsorbent Recirculating System (MARS) has been reported to reverse severe cholestasis-linked pruritus. Here, we report the first use of MARS during a spontaneous pregnancy and its successful outcome in a patient with PFIC3 and intractable pruritus. Albumin dialysis could be considered as a pregnancy-saving procedure in pregnant women with severe cholestasis and refractory pruritus. 展开更多
关键词 Albumin dialysis Intractable pruritus PREGNANCY Cholestatic liver disease
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A perspective on carbon materials for future energy application 被引量:16
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作者 Dang Sheng Su Gabriele Centi 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第2期151-173,共23页
Nanocarbon materials play a critical role in the development of new or improved technologies and devices for sustainable production and use of renewable energy. This perspective paper defines some of the trends and ou... Nanocarbon materials play a critical role in the development of new or improved technologies and devices for sustainable production and use of renewable energy. This perspective paper defines some of the trends and outlooks in this exciting area, with the effort of evidencing some of the possibilities offered from the growing level of knowledge, as testified from the exponentially rising number of publications, and putting bases for a more rational design of these nanomaterials. The basic members of the new carbon family are fullerene, graphene, and carbon nanotube. Derived from them are carbon quantum dots, nanohorn, nanofiber, nano ribbon, nanocapsulate, nanocage and other nanomorphologies. Second generation nanocarbons are those which have been modified by surface functionalization or doping with heteroatoms to create specific tailored properties. The third generation of nanocarbons is the nanoarchitectured supramolecular hybrids or composites of the first and second genera- tion nanocarbons, or with organic or inorganic species. The advantages of the new carbon materials, relating to the field of sustainable energy, are discussed, evidencing the unique properties that they offer for developing next generation solar devices and energy storage solutions. 展开更多
关键词 NANOCARBON CNT GRAPHENE hybrid carbon materials sustainable energy energy storage and conversion solar cells Li-batteries supercapac-itors
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Co-transplantation of neural stem cells and Schwann cells within poly (L-lactic-co-glycolic acid) scaffolds facilitates axonal regeneration in hemisected rat spinal cord 被引量:15
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作者 XIA Lei WAN Hong +7 位作者 HAO Shu-yu LI De-zhi CHEN Gang GAO Chuan-chuan LI Jun-hua YANG Fei WANG Shen-guo LIU Song 《Chinese Medical Journal》 SCIE CAS CSCD 2013年第5期909-917,共9页
Background Various tissue engineering strategies have been developed to facilitate axonal regeneration after spinal cord injury. This study aimed to investigate whether neural stem cells (NSCs) could survive in poly... Background Various tissue engineering strategies have been developed to facilitate axonal regeneration after spinal cord injury. This study aimed to investigate whether neural stem cells (NSCs) could survive in poly(L-lactic-co-glycolic acid) (PLGA) scaffolds and, when cografted with Schwann cells (SCs), could be induced to differentiate towards neurons which form synaptic connection and eventually facilitate axonal regeneration and myelination and motor function. Methods NSCs and SCs which were seeded within the directional PLGA scaffolds were implanted in hemisected adult rat spinal cord. Control rats were similarly injured and implanted of scaffolds with or without NSCs. Survival, migration, differentiation, synaptic formation of NSCs, axonal regeneration and myelination and motor function were analyzed. Student's t test was used to determine differences in surviving percentage of NSCs. One-way analysis of variance (ANOVA) was used to determine the differences in the number of axons myelinated in the scaffolds, the mean latency and amplitude of cortical motor evoked potentials (CMEPs) and Basso, Beattie & Bresnahan locomotor rating scale (BBB) score. The X2 test was used to determine the differences in recovery percentage of CMEPs. Results NSCs survived, but the majority migrated into adjacent host cord and died mostly. Survival rate of NSCs with SCs was higher than that of NSCs without SCs ((1.7831±0.0402)% vs. (1.4911±0.0313)%, P 〈0.001). Cografted with SCs, NSCs were induced to differentiate towards neurons and might form synaptic connection. The mean number of myelinated axons in PLGA+NSCs+SCs group was more than that in PLGA+NSCs group and in PLGA group ((110.25±30.46) vs. (18.25±3.30) and (11.25±5.54), P 〈0.01). The percentage of CMEPs recovery in PLGA+NSCs+SCs group was higher than in the other groups (84.8% vs, 50.0% and 37.5%, P 〈0.05). The amplitude of CMEPs in PLGA+NSCs+SCs group was higher than in the other gro 展开更多
关键词 spinal cord injury tissue engineering neural stem cells Schwann cells poly(L-lactic-co-glycolic acid) scaffold
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超快激光成丝现象研究综述 被引量:15
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作者 刘伟伟 薛嘉云 +1 位作者 苏强 陈瑞良 《中国激光》 EI CAS CSCD 北大核心 2020年第5期48-71,共24页
超快激光成丝是高功率超快激光在透明光学介质中传输时出现的一种独特非线性光学现象,所产生长度远超共焦范围的离子体通道被称为光丝;同时伴随超连续谱产生、荧光辐射和受激放大、脉冲自压缩等丰富的光学效应,在大气遥感、超快激光技... 超快激光成丝是高功率超快激光在透明光学介质中传输时出现的一种独特非线性光学现象,所产生长度远超共焦范围的离子体通道被称为光丝;同时伴随超连续谱产生、荧光辐射和受激放大、脉冲自压缩等丰富的光学效应,在大气遥感、超快激光技术、人工干预天气、激光超精细加工等方面具有广泛应用前景。本文对成丝现象研究的历史发展进行了简单介绍,包括实验技术、基本物理机制和调控方法的主要研究进展,并对成丝在大气远程应用、物理化学机制、强THz波产生等方面的研究所面临的挑战进行了展望。 展开更多
关键词 激光光学 超快激光 非线性光学 激光成丝 超快激光现象
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DDIT4 promotes gastric cancer proliferation and tumorigenesis through the p53 and MAPK pathways 被引量:14
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作者 Feng Du Lina Sun +9 位作者 Yi Chu Tingyu Li Chao Lei Xin Wang Mingzuo Jiang Yali Min Yuanyuan Lu Xiaodi Zhao Yongzhan Nie Daiming Fan 《Cancer Communications》 SCIE 2018年第1期474-487,共14页
Background:Gastric cancer(GC)is one of the most common malignancies worldwide,particularly in China.DNA damage-inducible transcript 4(DDIT4)is a mammalian target of rapamycin inhibitor and is induced by various cellul... Background:Gastric cancer(GC)is one of the most common malignancies worldwide,particularly in China.DNA damage-inducible transcript 4(DDIT4)is a mammalian target of rapamycin inhibitor and is induced by various cellular stresses;however,its critical role in GC remains poorly understood.The present study aimed to investigate the poten-tial relationship and the underlying mechanism between DDIT4 and GC development.Methods:We used western blotting,real-time polymerase chain reaction,and immunohistochemical or immunoflu-orescence to determine DDIT4 expression in GC cells and tissues.High-content screening,cell counting kit-8 assays,colony formation,and in vivo tumorigenesis assays were performed to evaluate cell proliferation.Flow cytometry was used to investigate cell apoptosis and cell cycle distribution.Results:DDIT4 was upregulated in GC cells and tissue.Furthermore,downregulating DDIT4 in GC cells inhibited proliferation both in vitro and in vivo and increased 5-fluorouracil-induced apoptosis and cell cycle arrest.In contrast,ectopic expression of DDIT4 in normal gastric epithelial cells promoted proliferation and attenuated chemosensitivity.Further analysis indicated that the mitogen-activated protein kinase and p53 signaling pathways were involved in the suppression of proliferation,and increased chemosensitivity upon DDIT4 downregulation.Conclusion:DDIT4 promotes GC proliferation and tumorigenesis,providing new insights into the role of DDIT4 in the tumorigenesis of human GC. 展开更多
关键词 DNA damage-inducible transcript 4 Gastric cancer PROLIFERATION Mitogen-activated protein kinase P53
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CYP72A67 Catalyzes a Key Oxidative Step in Medicago truncatula Hemolytic Saponin Biosynthesis 被引量:13
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作者 Elisa Biazzi Maria Carelli +5 位作者 Aldo Tava Pamela Abbruscato Ilaria Losini Pinarosa Avato Carla Scotti Ornella Calderini 《Molecular Plant》 SCIE CAS CSCD 2015年第10期1493-1506,共14页
In the Medicago genus, triterpenic saponins are bioactive secondary metabolites constitutively synthesized in the aerial and subterranean parts of plants via the isoprenoid pathway. Exploitation of saponins as pharmac... In the Medicago genus, triterpenic saponins are bioactive secondary metabolites constitutively synthesized in the aerial and subterranean parts of plants via the isoprenoid pathway. Exploitation of saponins as pharmaceutics, agrochemicals and in the food and cosmetic industries has raised interest in identifying the enzymes involved in their synthesis. We have identified a cytochrome P450 (CYP72A67) involved in hemolytic sapogenin biosynthesis by a reverse genetic TILLING approach in a Medicago truncatula ethyl- methanesulfonate (EMS) mutagenized collection. Genetic and biochemical analyses, mutant complementation, and expression of the gene in a microsome yeast system showed that CYP72A67 is responsible for hydroxylation at the C-2 position downstream of oleanolic acid synthesis. The affinity of CYP72A67 for substrates with different substitutions at multiple carbon positions was investigated in the same in vitro yeast system, and in relation to two other CYP450s (CYP72A68) responsible for the production of medicagenic acid, the main sapogenin in M. truncatula leaves and roots. Full sib mutant and wild-type plants were compared for their sapogenin profile, expression patterns of the genes involved in sapogenin synthesis, and response to inoculation with Sinorhizobium meliloti. The results obtained allowed us to revise the hemolytic sapogenin pathway in M. truncatula and contribute to highlighting the tissue specificities (leaves/roots) of sapogenin synthesis. 展开更多
关键词 Medicago truncatula saponin pathway cytochrome P450 CYP72A67 CYP72A68 TILLING analysis
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