检索结果-南通市图书馆

Regulation of intestinal stem cell fate specification

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2015年第6期58卷 570-578页

作者： QI Zhen CHEN ye-guang State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua-Peking Center for Life Sciences School of Life SciencesTsinghua University

The remarkable ability of rapid self-renewal makes the intestinal epithelium an ideal model for the study of adult stem cells. The intestinal epithelium is organized into villus and crypt, and a group of intestinal stem cells located at the base of crypt are responsible for this constant self-renewal throughout the life. Identification of the intestinal stem cell marker Lgr5, isolation and in vitro culture of Lgr5+ intestinal stem cells and the use of transgenic mouse models have significantly facilitated the studies of intestinal stem cell homeostasis and differentiation, therefore greatly expanding our knowledge of the regulatory mechanisms underlying the intestinal stem cell fate determination. In this review, we summarize the current understanding of how signals of Wnt, BMP, Notch and EGF in the stem cell niche modulate the intestinal stem cell fate.

关键词： intestinal stem cells Wnt BMP Notch EGF fate specification

Interplay between TGF-β signaling and receptor tyrosine kinases in tumor development

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2017年第10期60卷 1133-1141页

作者： Qiaoni Shi ye-guang Chen State Key Laboratory of Membrane Biology Tsinghua-Peking Center for Life Sciences School of Life Sciences Tsinghua University Beijing 100084 China

Transforming growth factor-β(TGF-β) signaling regulates cell proliferation, differentiation, migration and death, and plays a critical role in embryogenesis and tissue homeostasis. Its deregulation results in various diseases including tumor *** tyrosine kinases(RTKs), such as epidermal growth factor receptor(EGFR), fibroblast growth factor receptor(FGFR),vascular endothelial growth factor receptor(VEGFR) and platelet-derived growth factor receptor(PDGFR), also play key roles in the development and progression of many types of tumors. It has been realized that TGF-β signaling and RTK pathways interact with each other and their interplay is important for cancer development. They are mutually regulated and cooperatively modulate cell survival and migration, epithelial-mesenchymal transition, and tumor microenvironment to accelerate tumorigenesis and tumor metastasis. RTKs can modulate Smad-dependent transcription or cooperate with TGF-β to potentiate its oncogenic activity,while TGF-β signaling can in turn control RTK signaling by regulating their activities or expression. This review summarizes current understandings of the interplay between TGF-β signaling and RTKs and its influence on tumor development.

关键词： TGF-β receptor tyrosine kinase crosstalk tumor development

BMP signaling in homeostasis, transformation and inflammatory response of intestinal epithelium

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2018年第7期61卷 800-807页

作者： Shan Wang ye-guang Chen The State Key Laboratory of Membrane Biology Tsinghua-Peking Center for Life Sciences School of Life Sciences Tsinghua University

Intestine is the organ for food digestion, nutrient absorption and pathogen defense, in which processes intestinal epithelium plays a central role. Intestinal epithelium undergoes fast turnover, and its homeostasis is regulated by multiple signaling pathways,including Wnt, Notch, Hippo and BMP pathways. BMP signaling has been shown to negatively regulate self-renewal of Lgr5^+ intestinal stem cells, constrains the expansion of intestinal epithelium, therefore attenuating colorectal cancer formation. BMPs and their receptors are expressed in both epithelial and mesenchymal cells, suggesting a two-way interaction between the mesenchyme and epithelium. In this review, we summarize the current understanding of the function of BMP signaling in homeostasis, cancerous transformation and inflammatory response of intestinal epithelium.

关键词： intestinal epithelium BMP signaling Smad ISC CRC

Ultrahigh performance concrete–properties, applications and perspectives

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2015年第4期58卷 587-599页

作者： GU Chun Ping ye guang SUN Wei School of Materials Science & Engineering Southeast University Microlab Faculty of Civil Engineering and Geosciences Delft University of Technology Jiangsu Key Laboratory of Construction Materials Collaborative Innovation Center for Advanced Civil Engineering Materials

Over the last twenty years,remarkable advances have taken place in the research and application of ultra-high performance concrete(UHPC),which exhibits outstanding mechanical properties and excellent *** has shown great potential for the next generation infrastructure construction from the sustainability point of *** paper will give an overview on UHPC,with particular focus on the properties,applications and *** several decades of development,several types of commercial UHPC materials are available in the market,and the properties of UHPC have been characterized by numerous experimental and field *** speaking,the performance(*** properties and durability)of UHPC is much better than normal concrete(NC)and high performance concrete(HPC).Therefore,the uses of UHPC are growing all over the world,in both fields of new construction and ***,it is still a special material and technology,which is not worldwide *** some application prospects of UHPC are briefly introduced in the paper,and the efforts,which have to be made to turn UHPC into a widespread‘regular’technology,are *** paper aims to help designers,engineers,architects and infrastructure owners to know the capacities of UHPC and thus to increase the applications of this material.

关键词： UHPC characteristics durability applications perspectives

Fine-tune of intrinsic ERK activity by extrinsic BMP signaling in mouse embryonic stem cells

在线全文

学校读者我要写书评

暂无评论

Protein & Cell 2012年第6期3卷 401-404页

作者： Zhongwei Li ye-guang Chen The State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua-Peking Center for Life SciencesSchool of Life SciencesTsinghua UniversityBeijing 100084China

Embryonic stem(ES)cells hold great promise in regen-erative medicine and it is an urgent task to understand the underlying molecular mechanisms that control ES cell fate choice between self-renewal and *** mouse ES cells,extrinsic leukemia inhibitory factor(LIF)and bone morphogenetic protein(BMP)signaling pathways play pivotal roles in maintaining the self-renewal status under serum and feeder free culture *** extracellularsignal regulated kinase(ERK)activity is also important in determining mouse ES cell fate-low ERK activity keeps mouse ES cell self-renewal while high ERK activity drives differentiation.

关键词： BMP renewal intrinsic

ALK-mediated Tyr95 phosphorylation of Smad4 impairs its transcription activity and the tumor suppressive activity of TGF-β

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2019年第3期62卷 431-432页

作者： Qiaoni Shi ye-guang Chen The State Key Laboratory of Membrane Biology Tsinghua-Peking Center for Life Sciences School of Life Sciences Tsinghua University

Transforming growth factorβ(TGF-β)regulates various physiological processes such as cell proliferation,differentiation,morphogenesis,andt tissue homeostasis and *** deregulation of these processes leads to many types of human diseases such as cancer(Massague,2008).TGF-βsignaling is initiated upon active TGF-βdimer binding to the type II receptor TβRII and the type I receptor TβRI on cell surface.

关键词： TGF-β Smad4 its

Quantum information processing with nuclear spins mediated by a weak-mechanically controlled electron spin

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2022年第5期74卷 15-23页

作者： Wan-Jun Su guang-Zheng ye Department of Physics Fuzhou UniversityFuzhou 350002 China

We propose a scheme to achieve nuclear–nuclear indirect interactions mediated by a mechanically driven nitrogen-vacancy(NV)center in a *** we demonstrate twoqubit entangling gates and quantum-state transfer between two carbon *** the dipole–dipole interaction strength is much larger than the driving field strength,the scheme is robust against decoherence caused by coupling between the NV center(nuclear spins)and the ***,precise control of dipole coupling is not required so this scheme is insensitive to fluctuating positions of the nuclear spins and the NV *** scheme provides a general blueprint for multi-nuclear-spin gates and for multi-party communication.

关键词： dipole–dipole interaction mechanically control NV center quantum Zeno effect

Effects of entecavir and lamivudine for hepatitis B decompensated cirrhosis: Meta-analysis

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2013年第39期19卷 6665-6678页

作者： Xiao-guang ye Qi-Min Su Department of Infectious Diseases the SecondAffiliated Hospital of Guangzhou Medical University

AIM:To compare the effects of entecavir(ETV)and lamivudine(LAM)for the treatment of hepatitis B decompensated cirrhosis using a ***:We conducted a literature search for all eligible studies published prior to May 30,2013 using PUBMED,MEDLINE,EMBASE,the China National Knowledge Infrastructure(CNKI),the VIP database,the Wanfang database and the Cochrane Controlled Trial *** controlled trials(RCTs)comparing ETV with LAM for the treatment of hepatitis B decompensated cirrhosis were *** data were analyzed with Review Manager Software *** used RR as an effect measure,and reported its95%*** meta-analysis was performed using either a fixed-effect or random-effect model,based on the absence or presence of significant *** reviewers assessed the risk of bias and extracted data independently and in *** analysis was executed using the main outcome parameters including hepatitis B virus(HBV)DNA undetectability,HBV DNA level,hepatitis B e antigen(HBeAg)seroconversion,alanine aminotransferase(ALT)level,albumin level,total bilirubin(TBIL)level,prothrombin time activity(PTA)level,Child-Turcotte-Pugh(CTP)score,mortality,drugresistance,and adverse ***-analysis of the included trials and subgroup analyses were conducted to examine the association between pre-specified characteristics and the therapeutic effects of the two ***:Thirteen eligible trials(873 patients in total)were included and evaluated for methodological quality and *** these studies,all had baseline comparability,12 of them reported baseline values of the two treatment groups in *** various treatment durations(12,24,36,48 and>48 wk),both ETV and LAM significantly reduced HBV DNA level,however,reductions were greater in the ETV group(MD=-0.66,95%CI:-0.83-0.50,P<0.00001),(MD=-0.93,95%CI:-1.36-0.51,P<0.0001),(MD=-1.4,95%CI:-1.78-1.01,P<0.00001),(MD=-1.18,95%CI:-1.90-0.46,P=0.001),(MD=-0.14,95%CI:-0.17-0.

关键词： Hepatitis B Decompensated cirrhosis Entecavir Lamivudine Randomized controlled trial Metaanalysis.

Influence of Na_2CO_3 as Additive on Direct Reduction of Boron-bearing Magnetite Concentrate

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2016年第2期23卷 103-108页

作者： Yong-li LI Jing-kui QU guang-ye WEI Tao QI National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process EngineeringChinese Academy of Sciences Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of Sciences

Boron-bearing magnetite concentrate is typically characterized by low grade of iron and boron （wTFe = 51%- 54%, WB2O3 =6%-8%）, as well as the close intergrowth of ascharite phase and magnetite phase. A promising technology was proposed to separate iron and boron by coupling the direct reduction of iron oxides and Na activation of boron minerals together. The influence of Na2CO3 as additive on the direct reduction of boron-bearing magnetite was studied by chemical analysis, kinetic analysis, XRD analysis and SEM analysis. The results showed that the ad- dition of Na2CO3 not only activated boron minerals, but also reduced the activation energy of the reaction and pro- moted the reduction of iron oxides. Besides, the addition of Na2CO3 changed the composition and melting point of non-ferrous phase, and then promoted the growth and aggregation of iron grains, which was conducive to the subse- quent magnetic separation. Thus, the coupling of the two processes is advantageous,

关键词： ludwigite kinetic analysis direct reduction magnetic separation sodium carbonate