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一种具有避障保护功能的移动机器人的设计
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作者 程晶晶 周明龙 《内燃机与配件》 2024年第16期118-121,共4页
一种具有避障保护功能的移动机器人,主要包括基体、前防护板、滚筒、后防护板、支撑杆组。该具有避障保护功能的移动机器人,设置有滚筒和支撑杆组,当移动机器人遇到突然出现的障碍物时,通过滚筒进行滚动导向消能,减小撞击产生的冲击力,... 一种具有避障保护功能的移动机器人,主要包括基体、前防护板、滚筒、后防护板、支撑杆组。该具有避障保护功能的移动机器人,设置有滚筒和支撑杆组,当移动机器人遇到突然出现的障碍物时,通过滚筒进行滚动导向消能,减小撞击产生的冲击力,同时前防护板受到撞击向侧槽中收缩移动时,带动第一支撑杆以及第二支撑杆进行转动,使得套块沿连接轴进行滑动,通过第二弹簧的弹性作用力对冲击力进行缓冲,避免撞击产生的冲击力过大时,对机器人的内部零件造成损坏,起到缓冲避障保护的效果。 展开更多
关键词 移动机器人 障保护 支撑杆组
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保护地土壤的变化障害与综合治理
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作者 程铭 臧壮望 《现代农业科技》 2007年第6期40-,42,共2页
介绍了保护地土壤主要变化及障害发生的原因,提出了保护地土壤障害的综合治理措施。
关键词 保护地土壤 发生 原因 治理措施
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歼击机边界保护的动态矩阵控制方法 被引量:3
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作者 郑馨睿 吴庆宪 叶辉 《电光与控制》 北大核心 2016年第11期27-32,共6页
针对新一代歼击机,基于避障思想研究了一种边界保护控制方法。首先运用动态逆控制器对飞机进行稳定控制;在此基础上利用避障思想生成关键飞行参数的安全边界,并用参数在线调节的动态矩阵控制方法修正飞机的控制量,确保飞机在安全边界内... 针对新一代歼击机,基于避障思想研究了一种边界保护控制方法。首先运用动态逆控制器对飞机进行稳定控制;在此基础上利用避障思想生成关键飞行参数的安全边界,并用参数在线调节的动态矩阵控制方法修正飞机的控制量,确保飞机在安全边界内飞行;最后将所设计的飞行控制系统用于新一代歼击机的机动飞行仿真。仿真结果证明了该边界保护控制系统的有效性。 展开更多
关键词 歼击机 边界保护 动态矩阵控制 飞行控制
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一起主变死区故障导致110kV变电站全站失电事故分析
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作者 周超 王洪富 《模具工程》 2015年第9期74-80,共7页
阐述了主变死区故障导致110kV变电站全站失电的保护动作过程及原因分析。通过对现场保护动作报告、录波分析,发现当故障点在主变低压侧开关和CT之间时,主变高后备保护因复压闭锁条件未开放造成高后备未动作,无法第一时间内切除故障... 阐述了主变死区故障导致110kV变电站全站失电的保护动作过程及原因分析。通过对现场保护动作报告、录波分析,发现当故障点在主变低压侧开关和CT之间时,主变高后备保护因复压闭锁条件未开放造成高后备未动作,无法第一时间内切除故障,引起对侧线路距离Ⅲ段动作、110kV备自投装置动作、主变差动动作等连锁反应,最终造成该变电站全站失电。 展开更多
关键词 全站失电 保护死区放 复压闭锁开放
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Study on the effect of four kinds of raw materials in hypertonic dehydration cell model
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作者 Yuanyuan Gao Qidan Tan +3 位作者 Chencan Cao Haifeng Chen Yuying Jia Lei Liu 《日用化学工业(中英文)》 CAS 北大核心 2024年第10期1218-1226,共9页
It aims to investigate the protective effects of sodium hyaluronate,panthenol,Portulaca oleracea L.and Calendula officinalis L.on hyperosmotic dehydration-induced injury of human immortalized keratinocytes(HaCaT).The ... It aims to investigate the protective effects of sodium hyaluronate,panthenol,Portulaca oleracea L.and Calendula officinalis L.on hyperosmotic dehydration-induced injury of human immortalized keratinocytes(HaCaT).The safety mass concentrations of four raw materials were screened by detecting cell viability,and the secretion of hyaluronic acid(HA)was determined using the ELISA method.The expression of HaCaT barrier function related genes(OVOL1,EREG,TGM1,TGM2,IVL,IRF6,THBS1,CASP14)was detected at the mRNA level to explore the regulatory effect of four raw materials on these genes.The results demonstrate that pretreatment with the four kinds of raw materials could increase the cell viability after hyperosmotic dehydration,promote the secretion of HA,and improve the expression of barrier function related genes after hyperosmotic dehydration,among which panthenol and Calendula officinalis L.are better.The results show that the four raw materials have a certain protective effect on the hyperosmotic dehydration cell model,which provides data support for its application in cosmetics. 展开更多
关键词 hypertonic dehydration cell model protective effect barrier repair efficacy evaluation of cosmetics soothing ingredients
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New Principle for Grounding Fault Feeder Detection in MV Distributions with Neutral Ineffectively Earthed 被引量:3
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作者 曾祥君 尹项根 +1 位作者 陈德树 张哲 《Journal of Southeast University(English Edition)》 EI CAS 2000年第1期64-69,共6页
A new principle for grounding fault feeder detection based on negative sequence current variation and energy dissipated in the fault point is presented. It has high precision in both isolated systems and resonance ear... A new principle for grounding fault feeder detection based on negative sequence current variation and energy dissipated in the fault point is presented. It has high precision in both isolated systems and resonance earthed systems, even in full compensated systems. And it can be installed at the local control unit of feeder in distribution automation systems, such as field terminal unit (FTU). This principle is verified by EMTP simulator and experimentation. 展开更多
关键词 protective relaying fault detection distribution networks
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RCD及电气火灾监控系统设计易错问题评析 被引量:1
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作者 李蔚 张院 +1 位作者 和宏亮 白建光 《智能建筑电气技术》 2012年第3期13-19,共7页
本文以国家现行的多种规范和标准为依据,对剩余电流动作保护器(RCD)的设置及电气火灾监控系统设计中的易错问题进行了归纳总结,剖析了这些问题的症结所在,并有针对性地提出了改进措施,旨在澄清模糊概念、把握规范精髓、提升设计质量。
关键词 剩余电流动作保护 动作电流 动作时间 接地故 障保护 选择性配合 电磁式 电子式 设计标准 配置要求
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Glutamine and recombinant human growth hormone protect intestinal barrier function following portal hypertension surgery 被引量:22
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作者 Zhao-Feng Tang Yun-Biao Ling Nan Lin Zheng Hao Rui-Yun Xu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第15期2223-2228,共6页
AIM: To evaluate the effects of combined treatment of glutamine (Gln) and recombinant human growth hormone(rhGH) on intestinal barrier function following portal hypertension surgery. METHODS: This study was desi... AIM: To evaluate the effects of combined treatment of glutamine (Gln) and recombinant human growth hormone(rhGH) on intestinal barrier function following portal hypertension surgery. METHODS: This study was designed as a prospective, randomized and controlled clinical trial. Forty two patients after portal hypertension surgery were randomly assigned into 2 groups: control group (n = 20) and supplemental group (adding Gin and rhGH, n = 22). Every patient received isocaloric and isonitrogenous standard total parenteral nutrition (TPN) starting 3 d after surgery for 7 d. Blood samples were obtained before surgery and at the 3rd and 10th day postoperatively. Host immunity was evaluated by measuring levels of CD4, CD8, CD4/CD8, IgG, IgM and IgA, and the inflammatory responses were determined by assessing IL-2, TNF-α and C-reactive protein (CRP) levels. Intestinal permeability and integrity was evaluated by L/M test and histological examination, respectively. RESULTS: On postoperative d 10, CD4, CD4/CD8, IgG and IL-2 levels in supplemental group were significantly higher than those in control group (33.7±5.5 vs 31.0 ± 5.4, P 〈 0.05, (1.17±0.32 vs 1.05 ± 0.15, P 〈 0.05, 13.94±1.09 vs 12.33±1.33, P 〈 0.05, and 368.12 ± 59.25 vs 318.12 ± 45.65, P 〈 0.05, respectively), whereas the increase in serum TNF-α concentration was significantly reduced (41.02 ± 27.56 vs 160.09 ± 35.17, P 〈 0.05). The increase in L/M ratio was significantly lower in the supplemental group than in the control group (0.0166 ± 0.0017 vs 0.0339 ± 0.0028, P 〈 0.05). Moreover, mucosal integrity in the supplemental group was better than in the control group.CONCLUSION: Postoperative administration of TPN supplemented with Gin and rhGH in patients after portal hypertension surgery improves immune function, modulates inflammatory response, prevents the intestinal mucous membrane from atrophy and preserves intestinal integrity. 展开更多
关键词 Liver cirrhosis Portal hypertension Total parenteral nutrition Intestinal barrier function
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Active dynamic pre-protection mechanism for MPLS-TP network 被引量:1
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作者 白晖峰 Ji Yuefeng 《High Technology Letters》 EI CAS 2011年第4期354-359,共6页
The active-fault-alarm (AFA) technologies and the dynamic protection mechanism of the optical network controlled by the multi-protocol label switching transport profile (MPLS-TP) are both studied in this article. ... The active-fault-alarm (AFA) technologies and the dynamic protection mechanism of the optical network controlled by the multi-protocol label switching transport profile (MPLS-TP) are both studied in this article. On this basis, an active dynamic pre-protection (ADPP) mechanism is proposed. This active dynamic pre-protection mechanism is allowed to establish a so called temporary protection path (TPP) for the work path before a potential fault occurs and to switch to TPP only after the fault occurs. It keeps the TPP flexibly only when it is in low- quality or fault state to realize dynamic protection even better and to achieve better resource utilization. Simulation results show that the proposed new mechanism has better performance in terms of the flexibility and the efficiency from the perspective of time. 展开更多
关键词 multiple protocol label switching transport profile (MPLS-TP) active-fault-alarm (AFA) network protection
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The Study on Wireless Mesh Networks Security based on Improved Coding Scheme
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《International English Education Research》 2014年第1期10-12,共3页
In a multi-hop wireless mesh network, wireless links are vulnerable due to severe channel fading, interference and physical damage. In this paper, we will provide a coding scheme to protect from multiple failures in w... In a multi-hop wireless mesh network, wireless links are vulnerable due to severe channel fading, interference and physical damage. In this paper, we will provide a coding scheme to protect from multiple failures in wireless mesh networks to achieve high throughput where the redundancy is considered for the average number of failures. Our coding scheme is designed to protect from the average number of failures to increase the network throughput. When the number of failures is more than the average case, the destination will have to wait for more coded packets in the following time slots. 展开更多
关键词 Network Security link failure survivability.
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Elimination of ESD Events and Optimizing Waterjet Deflash Process for Reduction of Leakage Current Failures on QFN-mr Leadframe Devices
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作者 Frederick Ray I.Gomez Tito T.Mangaoang Jr. 《Journal of Electrical Engineering》 2018年第4期238-243,共6页
This technical paper presents the resolution of high leakage current failures on QFN-mr (Quad-Flat No-leads Multi-Row) LF (leadframe) devices by optimizing the waterjet deflash process and eliminating the ESD (el... This technical paper presents the resolution of high leakage current failures on QFN-mr (Quad-Flat No-leads Multi-Row) LF (leadframe) devices by optimizing the waterjet deflash process and eliminating the ESD (electrostatic discharge) events. ESD damage to units can cause permanent or latent product failures which results in low final test yield, and worse, possible external customer complaints. The use of CO2 (carbon dioxide) bubbler was able to reduce the DI (deionized) water’s equivalent resistivity from 17 M? to 0.30 M?, minimizing the tribocharging effect produced during the waterjet deflash process. Moreover, ESD events were eliminated by grounding the floating assembly equipment parts and installing appropriate ESD controls. It is of high importance to reduce or eliminate the leakage current failures to ensure the product quality, especially as the market becomes more demanding. After the optimization and implementation of the corrective and improvement actions, high leakage current occurrence was significantly reduced from baseline of 5,784 ppm to 20 ppm. 展开更多
关键词 Leakage current failure ESD QFN-mr LF waterjet deflash process.
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Analysis on preserving or increasing the value of social security funds under the new normal economy in China
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作者 Longquan Xu Ge Peng 《International English Education Research》 2015年第6期83-85,共3页
The "new normal" is the current stage of development of China's economy. The "new" in new normal means different to past; the "normal" means relatively stable. For a period of time in the future, the decrease o... The "new normal" is the current stage of development of China's economy. The "new" in new normal means different to past; the "normal" means relatively stable. For a period of time in the future, the decrease of potential growth rate has become an indisputable fact. Social security fund is an important source of funds for the protection of people's livelihood, whose every movement often attract much attention. Under the situation of new normal economy, how to ensure the preserving or increasing value of social security funds on the premise of security is the core task in the operations management of social security fund investment. At present, there are some difficulties in the development of the social security funds, such as the management system and operation mechanism are not perfect, some institutional measures have not been fully implemented and the progress of the law and regulations is slow. In this paper, we will put forward some corresponding improvement measures, such as expand the scope of social security fund investment, accelerate the implementation of the nominal account system and strengthen the actuarial management of social security fund. 展开更多
关键词 The new normal economy Social security fund Preserve or increase the value.
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Novel Algorithm for Estimating the Distance of Open-Conductor Faults in HV Transmission Lines
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作者 Mahmoud Gilany Ahmed Al-Kandari Bahaa Hassan 《Journal of Energy and Power Engineering》 2012年第8期1301-1307,共7页
This paper presents an ANN (artificial neural networks)-based technique for improving the performance of distance relays against open-circuit faults in transmission networks. The technique utilizes the small capacit... This paper presents an ANN (artificial neural networks)-based technique for improving the performance of distance relays against open-circuit faults in transmission networks. The technique utilizes the small capacitive current measured in the open-phase plus the currents in the two healthy phases in calculating the open-circuit fault distance. The results obtained show that a distance relay with the proposed scheme will not only be able to detect the open-conductor condition in HVTL (high voltage transmission line) but also to locate the place of this fault regardless the value of the pre-fault current loading. There is no need for especial communication schemes since the existing media could work properly for the needs of the proposed technique. 展开更多
关键词 Distance relay open-conductor ANN transmission networks fault location.
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Applying Modern Communication Technology to Loss-of-Mains Protection
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作者 Kimmo Kauhaniemi Olli Rintamaki 《Journal of Energy and Power Engineering》 2012年第3期429-433,共5页
The protection of distribution networks is facing new challenges from an increasing amount of DG (distributed generation). Even though current technology provides satisfactory solutions to manage this new situation,... The protection of distribution networks is facing new challenges from an increasing amount of DG (distributed generation). Even though current technology provides satisfactory solutions to manage this new situation, LOM (loss-of-mains protection) is still considered problematic. The solution proposed in this paper focuses on the use of a line differential protection relay. It inherently contains a suitable communication channel and provides absolutely selective protection for the feeder. Furthermore, it prevents the feeder relays from false tripping for faults on the neighboring feeder. The present trend in protection communication points towards the use of fiber optics. For line differential protection, this means a fast and high-capacity communication link which enables the implementation of many advanced protection functions. In addition, a solid foundation for such a communication link is offered by the new IEC 61850 standard and Ethernet technologies. The basic functionality of the line differential protection enables the operation of both the feeder protection and the DG protection for any fault on the feeder. Furthermore, basic LOM protection methods can be applied as backup protection for failures on the communication link. 展开更多
关键词 LOM protection communication line differential protection IEC 61850 GOOSE.
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Fault Current Limiters and Impacts on the System Protection Behavior
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作者 J. Jager T. Keil 《Journal of Energy and Power Engineering》 2010年第10期54-57,共4页
A deregulated power market is making short-circuit currents likely to exceed the thermal or mechanical permissible limits of switchgear. Consequently fault current limiters (FCL) become more necessary in power syste... A deregulated power market is making short-circuit currents likely to exceed the thermal or mechanical permissible limits of switchgear. Consequently fault current limiters (FCL) become more necessary in power systems. The use of FCLs has an impact on the protection schemes and functions in power systems. Thus, before FCLs can be applied in the network, the impacts on existing protection system must be understood. Depending on the current limiting technique used, today's protection concepts may have to be adapted or revised to ensure proper network protection selectivity. A relationship between fault current limiters and protection schemes should be established by taking into account both protection and network specific issues, such as the impact of different FCL technologies, existing and new protection concepts, selectivity and innovative network. This paper is presenting a frame work for accomplishing this task. 展开更多
关键词 Fault current limiter first cycle behavior follow current protection system PICK-UP processing SELECTIVITY coordination.
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Protective effect of periplaneta americana extract on intestinal mucosal barrier function in patients with sepsis 被引量:21
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作者 Hongwei Zhang Liyou Wei +4 位作者 Zhenyu Zhang Shuzheng Liu Gang Zhao Jing Zhang Yanling Hu 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第1期70-73,共4页
OBJECTIVE: To investigate the effect of the periplaneta americana extract on the intestinal mucosal barrier and prognostic implications in patients with sepsis. METHODS: Sixty and six patients with sepsis were assig... OBJECTIVE: To investigate the effect of the periplaneta americana extract on the intestinal mucosal barrier and prognostic implications in patients with sepsis. METHODS: Sixty and six patients with sepsis were assigned randomly to treatment group (32 cases) and control group (32 cases). The extractfrom periplaneta americana plus conventional medication for sepsis was administered to the treatment group, while the control group only received conventional treatment. The gastrointestinal function scores and acute physiology and chronic health evaluation II (APACHE 11 ) scores of all subjects were documented at baseline, at days 1, 3 and 7 after treatment respectively and their blood endotoxin was tested at the same time points as well. The incidence of death was recorded for both groups throughout the trial. RESULTS: At days 3 and 7 after treatment, gastrointestinal function score, APACHE II, and endotoxin level in treatment group wasbetter than that in con- trol group and the difference between them was significant (both P〈0~05). Although the incidence of death in treatment group was less than that in control group, the difference between the two groups was not significant (P〉 0.05). CONCLUSION: The extract of periplaneta ameri- cana had protective effect on intestinal mucosal barrier and could improve the condition and prog- nosis in patients with sepsis. 展开更多
关键词 Periplaneta americana extract SEPSIS APACHE ENDOTOXINS Gastrointestinal diseases
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Pelvic autonomic nerve preservation in radical rectal cancer surgery:changes in the past 3 decades 被引量:11
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作者 Min-Hoe Chew Yu-Ting Yeh +1 位作者 Evan Lim Francis Seow-Choen 《Gastroenterology Report》 SCIE EI 2016年第3期173-185,I0001,共14页
The advent of total mesorectal excision(TME)together with minimally invasive techniques such as laparoscopic colorectal surgery and robotic surgery has improved surgical results.However,the incidence of bladder and se... The advent of total mesorectal excision(TME)together with minimally invasive techniques such as laparoscopic colorectal surgery and robotic surgery has improved surgical results.However,the incidence of bladder and sexual dysfunction remains high.This may be particularly distressing for the patient and troublesome to manage for the surgeon when it does occur.The increased use of neoadjuvant and adjuvant radiotherapy is also associated with poorer functional outcomes.In this review,we evaluate current understanding of the anatomy of pelvic nerves which are divided into the areas of the inferior mesenteric artery pedicle,the lateral pelvic wall and dissection around the urogenital organs.Surgical techniques in these areas are discussed.We also discuss the results in functional outcomes of the various techniques including open,laparoscopic and robotic over the last 30 years. 展开更多
关键词 total mesorectal excision pelvic autonomic nerve preservation urinary dysfunction sexual dysfunction
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Design, synthesis and pharmacological evaluation of caffeic acid phenethyl ester acylation as multifunctional neuroprotective agents against oxidative stress injury
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作者 朱仁宗 宁显玲 +3 位作者 张志丽 王孝伟 田超 刘俊义 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2013年第6期475-482,共8页
4-Acylated or 3,4-diacylated caffeic acid phenethyl ester (CAPE) was prepared as prodrug to improve its stability and lipid solubility. Their neuroprotective activities were assessed by H202 model and 6-OHDA model. ... 4-Acylated or 3,4-diacylated caffeic acid phenethyl ester (CAPE) was prepared as prodrug to improve its stability and lipid solubility. Their neuroprotective activities were assessed by H202 model and 6-OHDA model. The results showed that target compounds displayed positive abilities to protect PC 12 nerve cells from oxidative stress injury, superior to that of CAPE. Additionally, target compounds showed high blood-brain barrier permeability. 展开更多
关键词 Amyotrophic lateral sclerosis ACYLATION Caffeic acid phenethyl ester Neuroprotective agents Blood-brain barrier permeability
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Dysfunction of Wnt signaling and synaptic :lisassembly in neurodegenerative diseases 被引量:3
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作者 Silvia A. Purro Soledad Galli Patricia C. Salinas 《Journal of Molecular Cell Biology》 SCIE CAS CSCD 2014年第1期75-80,共6页
The molecular mechanisms that regulate synapse formation have been well documented. However, little is known about the factors that modulate synaptic stability. Synapse loss is an early and invariant feature of neurod... The molecular mechanisms that regulate synapse formation have been well documented. However, little is known about the factors that modulate synaptic stability. Synapse loss is an early and invariant feature of neurodegenerative diseases including Alzheimer's lAD) and Parkinson's disease. Notably, in AD the extent of synapse loss correlates with the severity of the disease. Hence, understanding the molecular mechanisms that underlie synaptic maintenance is crucial to reveal potential targets that will allow the development of ther- apies to protect synapses. Writs play a central role in the formation and function of neuronal circuits. Moreover, Wnt signaling compo- nents are expressed in the adult brain suggesting their role in synaptic maintenance in the adult. Indeed, blockade of Wnts with the Wnt antagonist Dickkopf-1 (Dkkl) causes synapse disassembly in mature hippocampal cells. Dkkl is elevated in brain biopsies from AD patients and animal models. Consistent with these findings, Amyloid-β (Aβ) oUgomers induce the rapid expression of Dkkl. Importantly, Dkkl neutralizing antibodies protect synapses against Aβ toxicity, indicating that Dkkl is required for Aβ-mediated synapse loss. In this review, we discuss the role of Wnt signaling in synapse maintenance in the adult brain, particularly in relation to synaptic loss in neurodegenerative diseases. 展开更多
关键词 Wnt signaling synaptic disassembly degenerative diseases Alzheimer's disease Dkkl synaptic maintenance
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