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Altered fear engram encoding underlying conditioned versus unconditioned stimulus initiated memory updating
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作者 TENG Shuaiwen WANG Xinrong +6 位作者 DU Bowen CHEN Xiaolin FU Guanzhou LIU Yunfei XU Shuqi SHUAI Jiachen CHEN Zheyu 《中国药理学与毒理学杂志》 CAS 北大核心 2023年第S01期64-64,共1页
OBJECTIVE It′s known that post-retrieval extinction but not extinction alone could erase fear memory. However, whether the coding pattern of original fear engrams is remodeled or inhibited remains largely unclear. He... OBJECTIVE It′s known that post-retrieval extinction but not extinction alone could erase fear memory. However, whether the coding pattern of original fear engrams is remodeled or inhibited remains largely unclear. Here we try to investigate whether the coding pattern of memory engrams is altered during post-retrieval extinction induced memory updating. METHODS To answer the question, by using activity-dependent neuronal-tagging technology, neuronal tracing technique combined with optogenetic manipulation and in vivo calcium imaging, we identified the fear and extinction cells in PrL and BLA and investigated the dynamic encoding of memory engram ensembles in the PrL and BLA during CS versus US initiated memory updating.RESULTS We found increased reactivation of engram cells in the prelimbic cortex and basolateral amygdala during memory updating. Moreover, conditioned stimulus and unconditioned stimulu sinitiated memory updating depend on the engram cells reactivation in the prelimbic cortex or basolateral amygdala respectively. Finally,we found memory updating causes increased overlapping between fear and extinction cells and the original fear engrams encoding was altered during memory updating. CONCLUSION Our data provide the first evidence to show the overlapping ensembles between fear and extinction cells and functional reorganization of original engrams underlying conditioned stimulus and unconditioned stimulus initiated memory updating. 展开更多
关键词 initiated EXTINCTION MEMORY
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Aberrant activation of latent transforming growth factor-β initiates the onset of temporomandibular joint osteoarthritis 被引量:16
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作者 Liwei Zheng Caixia Pi +9 位作者 Jun Zhang Yi Fan Chen Cui Yang Zhou Jianxun Sun Quan Yuan Xin Xu Ling Ye Xu Cao Xuedong Zhou 《Bone Research》 CAS CSCD 2018年第4期383-392,共10页
There is currently no effective medical treatment for temporomandibular joint osteoarthritis(TMJ-OA) due to a limited understanding of its pathogenesis. This study was undertaken to investigate the key role of transfo... There is currently no effective medical treatment for temporomandibular joint osteoarthritis(TMJ-OA) due to a limited understanding of its pathogenesis. This study was undertaken to investigate the key role of transforming growth factor-β(TGF-β)signalling in the cartilage and subchondral bone of the TMJ using a temporomandibular joint disorder(TMD) rat model, an ageing mouse model and a Camurati–Engelmann disease(CED) mouse model. In the three animal models, the subchondral bone phenotypes in the mandibular condyles were evaluated by μCT, and changes in TMJ condyles were examined by TRAP staining and immunohistochemical analysis of Osterix and p-Smad2/3. Condyle degradation was confirmed by Safranin O staining, the Mankin and OARSI scoring systems and type X collagen(Col X), p-Smad2/3 a and Osterix immunohistochemical analyses. We found apparent histological phenotypes of TMJ-OA in the TMD, ageing and CED animal models, with abnormal activation of TGF-βsignalling in the condylar cartilage and subchondral bone. Moreover, inhibition of TGF-β receptor I attenuated TMJ-OA progression in the TMD models. Therefore, aberrant activation of TGF-β signalling could be a key player in TMJ-OA development. 展开更多
关键词 TMJ OA TMD Aberrant activation of latent transforming growth factor initiates the onset of temporomandibular joint osteoarthritis
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BeiDou-3 Global Positioning System Officially Initiates Construction 被引量:1
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作者 ZONG Wen 《Aerospace China》 2017年第3期60-60,共1页
China’s Bei Dou-3 global positioning system has been officially initiated construction with four global networking satel ites to be launched by the end of this year,according to the announcement at the Sixth China An... China’s Bei Dou-3 global positioning system has been officially initiated construction with four global networking satel ites to be launched by the end of this year,according to the announcement at the Sixth China Annual Meeting of Satellite Navigation and Location Services in Shenzhen on September 16 and the First Satellite Application International Exposition held. 展开更多
关键词 BeiDou-3 Global Positioning System initiates Construction
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Standardization of Social Credit System Initiated in China 被引量:1
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作者 Tian Wu 《China Standardization》 2004年第2期37-40,共4页
关键词 Standardization of Social Credit System initiated in China
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Filamentation initiated by Cas2 and its association with the acquisition process in cells
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作者 Lei Wang Xin Yu +9 位作者 Mengjie Li Guiqin Sun Lin Zou Tiansheng Li Linlin Hou Yameng Guo Danfeng Shen Di Qu Xunjia Cheng Li Chen 《International Journal of Oral Science》 SCIE CAS CSCD 2019年第4期300-306,共7页
Cas1-and-Cas2-mediated new spacer acquisition is an essential process for bacterial adaptive immunity.The process is critical for the ecology of the oral microflora and oral health.Although molecular mechanisms for sp... Cas1-and-Cas2-mediated new spacer acquisition is an essential process for bacterial adaptive immunity.The process is critical for the ecology of the oral microflora and oral health.Although molecular mechanisms for spacer acquisition are known,it has never been established if this process is associated with the morphological changes of bacteria.In this study,we demonstrated a novel Cas2-induced filamentation phenotype in E.coli that was regulated by co-expression of the Cas1 protein.A 30 amino acid motif at the carboxyl terminus of Cas2 is necessary for this function.By imaging analysis,we provided evidence to argue that Cas-induced filamentation is a step coupled with new spacer acquisition during which filaments are characterised by polyploidy with asymmetric cell division.This work may open new opportunities to investigate the adaptive immune response and microbial balance for oral health. 展开更多
关键词 function. PROCESS initiated
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A Novel Continuously Initiated Polymerization by One-Atmosphere Low Temperature Plasma Device
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作者 尤庆亮 孟月东 +3 位作者 汪建华 区琼荣 徐旭 钟少峰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第2期2758-2760,共3页
A novel atmospheric plasma device developed in this paper, which is more effective and convenient to study the plasma-initiated polymerization (PIP) than conventional setup. The structure and mechanism of the device i... A novel atmospheric plasma device developed in this paper, which is more effective and convenient to study the plasma-initiated polymerization (PIP) than conventional setup. The structure and mechanism of the device is introduced. Some plasma-initiated polymerization experiments are carried out on the device, and the conversion of AA (Acrylic acid) and AM (Acryl amide) atmospheric (N2) plasma polymerization are respectively 89% and 94% after 120 h post polymerization, whereby IR spectra of the product (AA, AM). Our PIP result are confirmed. 展开更多
关键词 plasma initiated polymerization acrylic acid acryl amide atmospheric plasma
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Numerical Analysis of Plasma Initiated Polymerization
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作者 尤庆亮 汪建华 +4 位作者 孟月东 舒兴胜 区琼荣 徐旭 沈克明 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第4期433-437,共5页
Plasma initiated polymerization is a kind of well-known radical polymerization mechanism, but it has the 'living' polymerization feature and produces ultra-high molecular weight polymer. In order to explain such phe... Plasma initiated polymerization is a kind of well-known radical polymerization mechanism, but it has the 'living' polymerization feature and produces ultra-high molecular weight polymer. In order to explain such phenomena, we calculate the basic data of plasma initiated polymerization of methylmethacrylate (MMA) according to the principle of polymer physics and chemistry. It results in that the radical concentration ranges from 10^-12mol/L to 10^-16mol/L corresponding to the radical life in 10^4s to 10^8s, which means the radicals have a long lifetime. Moreover because of the long lifetime radicals it causes a unique feature rather than the common radical polymerization, and also shows no "living polymerization". It is noticed in experiments that there are two key factors playing important roles. One is the effective radical amount produced during the plasma discharging while the another is the diffusion factor. 展开更多
关键词 numerical analysis plasma initiated polymerization radical lifetime
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PHOTOSENSITIVITY OF CERIC ION INITIATED METHYL ACRYLATE POLYMERIZATION
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作者 Jian Hua DONG Jian Qing YANG Kun Yuan QIU Xin De FENG Department of Chemistry,Peking University,Beijing,100871 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第7期565-566,共2页
The polymerization of methyl acrylate was sensitive to UV light. Under UV light,the rate of polymerization is 8 times as high as the rate in dark.The overall activation energy was decreased by the UV light (313nm).A t... The polymerization of methyl acrylate was sensitive to UV light. Under UV light,the rate of polymerization is 8 times as high as the rate in dark.The overall activation energy was decreased by the UV light (313nm).A tentative explanation is given and the mechanism is discussed. 展开更多
关键词 UV NM IV PHOTOSENSITIVITY OF CERIC ION initiateD METHYL ACRYLATE POLYMERIZATION
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Studies on the Mechanism of Methyl Methacrylate Polymerization Initiated by Volatile and Nonvolatile Products of Methyl Methacrylate Plasma
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《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1995年第3期250-255,共6页
he volatile (VPP) and nonvolatile (NVPP) products of methyl methacrylate(MMA) reaction in plasma chamber were used as initiators of MMA polymeriza-tion. From the structure analyses of the two initiators, the measureme... he volatile (VPP) and nonvolatile (NVPP) products of methyl methacrylate(MMA) reaction in plasma chamber were used as initiators of MMA polymeriza-tion. From the structure analyses of the two initiators, the measurement of poly-merization kinetics, and the determination of the molecular weight of resultantpolymers , we found tliat MMA polymerization initiated by NVPP is a typical radical mechanism of polymerization which undergoes a process of continuous initiationand bifunction termination , while VPP-initiated polymerization suggested a mech-anism of living radical process fpolymerization with instantaneous initiation , chain-transfer to monomer , without termination). 展开更多
关键词 Plasma initiated polymerzation Methyl methacrylate Kinetics
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PRI: An Periodically Receiver-Initiated Task Scheduling Algorithm
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作者 石威 《High Technology Letters》 EI CAS 2000年第1期10-15,共6页
Task scheduling is a key problem for the distributed computation. This thesis analyzes receiver initiated(RI) task scheduling algorithm, finds its weakness and presents an improved algorithm PRI algorithm. This algo... Task scheduling is a key problem for the distributed computation. This thesis analyzes receiver initiated(RI) task scheduling algorithm, finds its weakness and presents an improved algorithm PRI algorithm. This algorithm schedules the concurrent tasks onto network of workstation dynamically at runtime, and initiates task scheduling by the node of low load. The threshold on each node can be modified according to the system information which is periodically detected. Meanwhile, the detecting period can be adjusted in terms of the change of the system state. The result of the experiments shows that the PRI algorithm is superior to the RI algorithm. 展开更多
关键词 Task scheduling Distributed computation RECEIVER initiated Network of WORKSTATIONS RUNTIME Low load THRESHOLD
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GRAFT POLYMERIZATION OF ACRYLAMIDE ONTO HOMOPOLYMER OF 5-METHYL-5-HEXEN-2, 4-DIONE INITIATED BY CERIC ION
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作者 赵京波 赵彤 丘坤元 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1997年第1期50-56,共7页
The homopolymerization of 5-methyl-5-hexen-2,4-dione (methacryloylacetone, MAA), a vinyl monomer having beta-diketone group, was carried out in the presence of benzophenone (BP)/N, N-dimenthyl-4-toluidine (DMT) system... The homopolymerization of 5-methyl-5-hexen-2,4-dione (methacryloylacetone, MAA), a vinyl monomer having beta-diketone group, was carried out in the presence of benzophenone (BP)/N, N-dimenthyl-4-toluidine (DMT) system. Graft polymerization of acrylamide initiated by eerie ion onto the homopolymer film was investigated and the mechanism of the grafting reaction was proposed on the basis of ESR study. The grafted copolymer was characterized by means of grafting percentage, water absorption, XPS spectra and scanning electron photomicrographs. 展开更多
关键词 poly(methacryloylacetone) photoinitiated polymerization graft polymerization redox initiation of beta-diketone pendant group with ceric ion
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Ghost writing initiated by commercial companies
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《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2005年第4期572-572,共1页
The integrity of the published record of scientific research depends not only on the validity of the science but also on honesty in authorship. Editors and readers need to be confident that authors have undertaken the... The integrity of the published record of scientific research depends not only on the validity of the science but also on honesty in authorship. Editors and readers need to be confident that authors have undertaken the work described and have ensured that the manuscript accurately reflects their work, irrespective of whether they took the lead in writing or sought assistance from a medical writer. The scientific record is distorted if the primary purpose of an article is to persuade readers in favor of a special interest, rather than to inform and educate, and this purpose is concealed. 展开更多
关键词 WORK Ghost writing initiated by commercial companies
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Novel Cyclization of 2-(o-Bromomethyl)benzylidene-1,3-indandione to 7,12-Dihydro-1-oxoindeno [3,2-c] [2]benzooxepine Initiated by an NAD(P)H Model:New Strategy to Seven-membered Oxacycle
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期262-262,共1页
关键词 benzooxepine initiated by an NAD o-Bromomethyl)benzylidene-1 3-indandione to 7 12-Dihydro-1-oxoindeno P)H Model Novel Cyclization of 2
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"Internet + Trade Promotion" Action Plan Initiates
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作者 Liu Xinwei 《China's Foreign Trade》 2016年第5期26-,共1页
2016 China(Beijing)Internet Application Innovation Development Forum,the CCPIT Commercial Sub-Council Internet Application Committee Inauguration was held in Beijing on September13,hosted by the CCPIT Sub-Council and ... 2016 China(Beijing)Internet Application Innovation Development Forum,the CCPIT Commercial Sub-Council Internet Application Committee Inauguration was held in Beijing on September13,hosted by the CCPIT Sub-Council and EventBank.As a trade promotion agency within the trade promotion system focusing on trade and investment promotion in the commercial and service sector。 展开更多
关键词 ICC INTERNET Action Plan initiates WILL
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RADICAL POLYMERIZATION OF VINYL MONOMER INITIATED BY CERIC ION/TARTARIC ACID
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作者 (Jian Hua DONG Da Hui LIU +1 位作者 Kun Yuan QIU Xin De FANG (Department of Chemistry, Peking University, Beijing 100871) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第6期523-526,共4页
The polymerization of acrylamide and acrylonitrile using ceric ion as initiator can be promoted greatly by the tartaric acid. The kinetics of acrylamide polymerization initiated by ceric ion/tartaric acid has been stu... The polymerization of acrylamide and acrylonitrile using ceric ion as initiator can be promoted greatly by the tartaric acid. The kinetics of acrylamide polymerization initiated by ceric ion/tartaric acid has been studied. The presence of the species of tartaric acid in Polyacrylonitrile produced by using ceric ion/tartaric acid as niitiator has been confirmed by FT-IR analysis. 展开更多
关键词 ION RADICAL POLYMERIZATION OF VINYL MONOMER initiateD BY CERIC ION/TARTARIC ACID
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Low Level of Hepatitis B Surface Antigen Screening in a Tertiary Health Facility in Nigeria 2000-2014: Imperative for Provider Initiated Testing and Counselling for Hepatitis B Virus?
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作者 Elon Warnow Isaac Iliya Jalo +5 位作者 Yaya Saidu Alkali Ayomikun Ajani Joshua Difa Abubakar John Tunde Aremu Christianah Oluwaseun Oyeniyi Mohammed Hassan Danlami 《Open Journal of Epidemiology》 2020年第3期251-264,共14页
<strong>Introduction:</strong> Viral hepatitis is a major public health challenge that requires an urgent response. Reducing mortality requires major scale-up in prevention, testing and treatment access;co... <strong>Introduction:</strong> Viral hepatitis is a major public health challenge that requires an urgent response. Reducing mortality requires major scale-up in prevention, testing and treatment access;coverage in HBV vaccination, testing and treatment is low and must accelerate massively to achieve the 2030 targets. Less than 1% of HBV-infected individuals are diagnosed in Sub-Sahara Africa, despite the availability of rapid tests with good diagnostic accuracy. <strong>Materials and Methods:</strong> This was retrospective cross sectional study conducted in Federal Teaching Hospital Gombe, in North East Nigeria. All children and adults who presented to the out-patient departments, and those that were admitted irrespective of their HIV and or Hepatitis C virus status and had Hepatitis B and/or Hepatitis B envelope antigen test were conducted between 2000 to 2015. All children and adults were tested using the Hospital standard for Hepatitis B surface antigen test strip. <strong>Results:</strong> Between 2000 and 2014, 739,456 children and adults were admitted and reviewed in the outpatient units of the Federal Teaching Hospital Gombe;there were 685,552 adults and 53,904 children. Children constituted 7.3% (53,904/739,456) of admissions and outpatient consultations. 2.8% (210/7570), 3.3% (773/23,783), 3.6% (1145/32,142), 5.2% (1694/33,043), 3.3% (986/29,216), 1.9% (661/3321), 0.1% (53/41,626), 0.2% (113/46,634), 2.6% (1418/54,423), 5.4% (3717/69,696), 3.7% (2332/62,086), 3.5% (3241/90,623), 3.2% (2881/89,398), 3.8% (2428/62,687), 2.8% (1835/63,208) of children and adults were tested for HBsAg in 2000, 2001, 20002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 and 2014 respectively. 23,487 children and adults were tested for HBsAg with a cumulative testing rate of 3%. Overall 4465/23,487 children and adults were seropositive for HBsAg giving a cumulative prevalence of 19%. <strong>Conclusion:</strong> HBV screening in our health facility is very low. Massive scale up in awareness and HBV vaccination are required. Provider initiated testing and counseling for HBV in health facilities needs support for implementation in Health Facilities in Sub Saharan Africa. 展开更多
关键词 Hepatitis B TESTING Provider initiated Counseling and Testing Sub-Saharan Africa
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ORGANOPHOSPHINE INITIATED REACTION OF PERFLUOROALKYL IODIDES WITH ALKENES
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作者 Wei Yuan HUANG Han Zhong ZHNG (Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,345 Lingling Lu,Shanghai 200032) 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第2期153-154,共2页
perfluoroalkyl iodides reacted with alkenes in acetonitrile solu- tion containing catalytic amount of organophosphine under mild condition to give the corresponding adducts in moderate to good yields.Reaction was show... perfluoroalkyl iodides reacted with alkenes in acetonitrile solu- tion containing catalytic amount of organophosphine under mild condition to give the corresponding adducts in moderate to good yields.Reaction was shown to involve a free radical mechanism. 展开更多
关键词 ORGANOPHOSPHINE initiateD REACTION OF PERFLUOROALKYL IODIDES WITH ALKENES
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To be Master by Honor and Disgrace to Initiate the First Rate Level by the Death-dsfving Spirit──Introduction of Heilongjiang Yuanbao Textile Holding Co., Ltd.
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《China's Foreign Trade》 2001年第9期46-46,共1页
关键词 Introduction of Heilongjiang Yuanbao Textile Holding Co To be Master by Honor and Disgrace to initiate the First Rate Level by the Death-dsfving Spirit
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New National Technical Standard Innovation Base initiated
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《China Standardization》 2021年第2期I0006-I0006,共1页
The construction of National Technical Standard Innovation Base(civil aviation)was initiated on February 25,marking another step forward in facilitating innovation outcomes to be converted into technical standards.
关键词 技术标准创新 AVIATION initiated
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Guang Dong, Hong Kong and Macao Initiates Cross-Region Cooperation in Protecting Intellectual Property
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作者 Shi Zhihong Mo Yaojiang +1 位作者 Wang Hu Hu Yuzhang 《China's Foreign Trade》 2002年第11期53-53,共1页
关键词 Guang Dong Hong Kong and Macao initiates Cross-Region Cooperation in Protecting Intellectual Property
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