维普中文期刊产品整合服务
886篇 您的检索式:作者名="Fei ZHU"
    题名 作者 年代 出处 被引量
1Inhibition of SARS-CoV-2 (previously 2019-nCoV) infection by a highly potent pan-coronavirus fusion inhibitor targeting its spike protein that harbors a high capacity to mediate membrane fusion显示文摘The recent outbreak of coronavirus disease(COVID-19)caused by SARS-CoV-2 infection in Wuhan,China has posed a serious threat to global public health.To develop specific anti-coronavirus therapeutics and prophylactics,the molecular mechanism that underlies viral infection must first be defined.Therefore,we herein established a SARS-CoV-2 spike(S)protein-mediated cell-cell fusion assay and found that SARS-CoV-2 showed a superior plasma membrane fusion capacity compared to that of SARS-CoV.We solved the X-ray crystal structure of six-helical bundle(6-HB)core of the HR1 and HR2 domains in the SARS-CoV-2 S protein S2 subunit revealing that several mutated amino acid residues in the HR1 domain may be associated with enhanced interactions with the HR2 domain.We previously developed a pan-coronavirus fusion inhibitor,EK1,which targeted the HR!domain and could inhibit infection by divergent human coronaviruses tested,including SARS-CoV and MERS-CoV.Here we generated a series of lipopeptides derived from EK1 and found that EK1C4 was the most potent fusion inhibitor against SARS-CoV-2 S protein-mediated membrane fusion and pseudovirus infection with IC50s of 1.3 and 15.8 nM,about 241-and 149-fold more potent than the original EK1 peptide,respectively.EK1C4 was also highly effective against membrane fusion and infection of other human coronavirus pseudoviruses tested,including SARS-CoV and MERS-CoV,as well as SARSr-CoVs,and potently inhibited the replication of 5 live human coronaviruses examined,including SARS-CoV-2.Intranasal application of EK1C4 before or after challenge with HCoV-OC43 protected mice from infection,suggesting that EK1C4 could be used for prevention and treatment of infection by the currently circulating SARS-CoV-2 and other emerging SARSr-CoVs.Shuai Xia Meiqin Liu Chao Wang Wei Xu Qiaoshuai Lan Siliang Feng Feifei Qi Linlin Bao Lanying Du Shuwen Liu Chuan Qin Fei Sun Zhengli Shi Yun Zhu Shibo Jiang Lu Lu 2020Cell Research2020,30,4:81
2Mapping wetland changes in China between 1978 and 2008显示文摘Four wetland maps for all China have been produced,based on Landsat and CBERS-02B remote sensing data between 1978 and 2008 (1978,1990,2000 and 2008).These maps were mainly developed by manual interpretation and validated by substantial field investigation in 2009.Based on these maps,we analyzed the 2008 wetland distribution in China and discussed wetland changes and their drivers over the past 30 years.(i) There were about 324097 km 2 of wetlands in 2008,for which inland marshes or swamps were the most common wetland type (35%),with lakes (26%) second.Most of the wetlands were in Heilongjiang,Inner Mongolia,Qinghai and Tibet,occupying about 55% of the national wetland area.(ii) From 1978 to 2008,China's wetland area continually and significantly decreased,by about 33% based on changes in the wetland map.This was in sharp contrast to the increase in artificial wetlands,which increased by about 122%.Inland marshes accounted for the main loss of total wetlands from 1978 to 2000.From 2000 through 2008,riverine and lacustrine wetlands constituted the main wetland loss.Fortunately however,the rate of wetland loss decreased from 5523 to 831 km 2 /a.(iii) The change ratio of lost natural wetlands (including inland and coastal wetlands) to non-wetlands has decreased slightly over the past 30 years.From 1978 to 1990,nearly all natural wetlands (98%) lost were transformed into non-wetlands.However,the ratio declined to 86% from 1990 to 2000,and to 77% from 2000 to 2008.(iv) All Chinese provinces were divided into three groups according to patterns of wetland changes,which could relate to the driving forces of such changes.Tibet was completely different from other provinces,as it was one representative example in which there was a net wetland increase,because of global warming and decreased human activity since 1990.Increased economic development caused considerable wetland loss in most eastern provinces,and artificial wetlands increased.NIU ZhenGuo ZHANG HaiYing WANG XianWei YAO WenBo ZHOU DeMin ZHAO KuiYi ZHAO Hui LI NaNa HUANG HuaBing LI CongCong YANG Jun LIU CaiXia LIU Shuang WANG Lin LI Zhan YANG ZhenZhong QIAO Fei ZHENG YaoMin CHEN YanLei SHENG YongWei GAO XiaoHong ZHU WeiHong WANG WenQing WANG Hong WENG YongLing ZHUANG DaFang LIU JiYuan LUO ZhiCai CHENG Xiao GUO ZiQi GONG Peng 2012Chinese Science Bulletin2012,57,22:51
3DK crush technique: modified treatment of bifurcation lesions in coronary artery显示文摘CHEN Shao-liang YE Fei ZHANG Jun-jie ZHU Zhong-sheng LIN Song SHAN Shou-jie LIU Zhi-zhong LIU Yan DUAN Bao-xiang GE Jun-bo 2005Chinese Medical Journal2005,,20:35
4Polymorphism Analyses of Hepatitis B Virus X Gene in Hepatocellular Carcinoma Patients from Southern China显示文摘长期的肝炎 B 病毒( HBV )感染是主要原因 ofhepatocellular 癌( HCC )之一,并且 HBV X ( HBx )基因在HBV相关的 HCC.We 的分子的致病起一个关键作用调查了是否有特别 HBx 基因变化,从南部的中国在病人与 HCC 联系。HBx 基因被嵌套的聚合酶链反应(PCR ) 从 HBVcarrier 与 HCC 和 25 件浆液样品从病人在 51paraffin-embedded 肿瘤织物样品检验,搁浅单人赛的 conformational 多型性 andheteroduplex 分析。有从肿瘤织物样品的潜在地重要的变化的 HBx 基因被克隆,在肿瘤织物样品与出版 HBx 基因 sequence.HBV 遗传型定序并且排列被在肿瘤织物的31.3% HBx 基因碎片取样的基因多型性显示出的 HBx 的嵌套的 PCR.Analyses 分析有特殊 pattern.A 在 29 点突变伴随的 HBxgene 的 nt 382-400 的普通删除随机在四被检测有在 HBx 开的读物引起了框架移动的这个模式的选择肿瘤织物样品在 atnt 上与一条新站鳕鱼装裱 1818 ,导致 HBx 多肽链在这些情况中在 C 结束截断了。在四件随机选择的样品之中,三是 HBV 遗传型 B ,并且一个人没被我们的现在的 assay.Inanother 肿瘤织物样品检测,全身的 HBx 基因的扩大产出揭示的这碎片的 shorterfragment.Sequencing 在 1577 HBVgene.These 和 1840 结果建议的 nt 之间的 264 bp 删除那个 HBx 基因变化在 HCC 样品经常发生,并且在 HBx 基因的 nt 382-400 的删除可能在南部的中国在 HCC 的 carcinogenesis 起一个作用。Ping'an ZHU Deming TAN Zhongtian PENG Fei LIU Lin SONG 2007Acta Biochimica et Biophysica Sinica2007,39,4:29
5Assessment of duodenogastric reflux by combined continuous intragastric pH and bilirubin monitoring显示文摘AIM: To assess the diagnostic value of a combination of continuous intragastric pH and bilirubin monitoring in the detection of duodenogastric reflux (DGR), and the effects of diet on the bilirubin absorbance.METHODS: 30 healthy volunteers were divided into twogroups: standard diet group (Group 1) 18 cases, free diet group (Group 2) 12 cases. Each subjects were subjected to simultaneous 24 hour intragastric pH and spectrophotometric bilirubin concentration monitoring (Bilitec 2000).RESULTS: There was no difference of preprandial phasebilirubin absorbance between two groups. The absorbanceof postprandial phase was significantly increased in group 2than group 1. There was no difference between preprandialphase and postprandial phase absorbance in group 1.Postprandial phase absorbance was significantly higher ingroup 2. In a comparison of bile reflux with intragastric pHduring night time, there were 4 types of reflux:Simultaneous increase in absorbance and pH in only 19.6%, increase in bilirubin with unchanged pH 33. 3 %, pHincrease with unchanged absorbance 36. 3 %, and bothunchanged in 10. 8 %. Linear regression analysis showed nocorrelation between percertage total time of pH < 4 aridpercentage total time of absortance > 0. 14, r=0.068, P<0.05.CONCLUSION: Because of the dietary effect, highabsorbance fluids or foods should be avoided in detection.Intrsgastric pH and bilirubin monitoring separately predictthe presence of duodenal (and/or pancreatic) reflux and bilereflux. They can not substitute for each other. The detectionof DGR is improved if the two parameters are combinedsimultanoously.Fei Dai Jun Gong Ru Zhang Jin-Yan Luo You-Ling Zhu Xue-Qin Wang,Department of Gastroenterology,Second Hospital of Xi’ an Jiaotong University,Xi’an 710004,Shaanxi Province,China 2002World Journal of Gastroenterology2002,8,2:30
6Revisiting the security of quantum dialogue and bidirectional quantum secure direct communication显示文摘From the perspective of information theory and cryptography,the security of two quantum dialogue protocols and a bidirectional quantum secure direct communi-cation(QSDC) protocol was analyzed,and it was pointed out that the transmitted information would be partly leaked out in them.That is,any eavesdropper can elicit some information about the secrets from the public annunciations of the legal us-ers.This phenomenon should have been strictly forbidden in a quantum secure communication.In fact,this problem exists in quite a few recent proposals and,therefore,it deserves more research attention in the following related study.GAO Fei GUO FenZhuo WEN QiaoYan ZHU FuChen 2008Science China(Physics,Mechanics & Astronomy)2008,51,5:28
7A reappraisal of CTLA-4 checkpoint blockade in cancer immunotherapy显示文摘anti-CTLA-4 抗体由阻止 B7-CTLA-4 相互作用接近否定发信号引起肿瘤拒绝,这被假定。在比临床上有效的 dosing 完成的血浆层次更加高的集中,令人惊讶地, anti-CTLA-4 抗体 Ipilimumab 不由 CTLA-4 也不 CTLA-4 绑定堵住任何一 B7 trans-endocytosis 到使不能调动或联系房间的 B7。因而, Ipilimumab 不从人性化的任何一个 CTLA4 基因在树枝状的房间(DC ) 上增加 B7 (Ctla4 h/h ) 或人的 CD34 + 茎重新组成房间的 NSG 老鼠。在 Ctla4 高效地表示人和老鼠 CTLA4 基因,绑在人的 anti-CTLA-4 抗体然而并非老鼠 CTLA-4 的 h/m 老鼠导致 Treg 弄空和 Fc 受体依赖者肿瘤拒绝。堵住的抗体 L3D10 比得上在引起肿瘤拒绝的非阻塞的 Ipilimumab。显著地,输在人类化期间堵住活动的 L3D10 子孙在导致 Treg 弄空和肿瘤拒绝仍然保持充分能干。有效地在淋巴的器官堵住 CD4 T 细胞激活和 de novo CD8 T 细胞 priming 的 Anti-B7 抗体否定地不影响 Ipilimumab 的 immunotherapeutic 效果。因此,临床上有效的 anti-CTLA-4 mAb 由独立于检查点封锁的机制引起肿瘤拒绝但是依赖于主人 Fc 受体。我们为 CTLA-4 检查点的一个重评价的数据电话封锁假设并且为安全、有效的 anti-CTLA-4 mAbs 的下一代提供新卓见。Xuexiang Du Fei Tang Mingyue Liu Juanjuan Su Yan Zhang Wei Wu Martin Devenport Christopher A Lazarski Peng Zhang Xu Wang Peiying Ye Changyu Wang Eugene Hwang Tinghui Zhu Ting Xu Pan Zheng Yang Liu 2018Cell Research2018,28,4:25
8Minimal invasive microscopic tooth preparation in esthetic restoration: a specialist consensus显示文摘By removing a part of the structure,the tooth preparation provides restorative space,bonding surface,and finish line for various restorations on abutment.Preparation technique plays critical role in achieving the optimal result of tooth preparation.With successful application of microscope in endodontics for>30 years,there is a full expectation of microscopic dentistry.However,as relatively little progress has been made in the application of microscopic dentistry in prosthodontics,the following assumptions have been proposed:Is it suitable to choose the tooth preparation technique under the naked eye in the microscopic vision?Is there a more accurate preparation technology intended for the microscope?To obtain long-term stable therapeutic effects,is it much easier to achieve maximum tooth preservation and retinal protection and maintain periodontal tissue and oral function health under microscopic vision?Whether the microscopic prosthodontics is a gimmick or a breakthrough in obtaining an ideal tooth preparation should be resolved in microscopic tooth preparation.This article attempts to illustrate the concept,core elements,and indications of microscopic minimally invasive tooth preparation,physiological basis of dental pulp,periodontium and functions involved in tool preparation,position ergonomics and visual basis for dentists,comparison of tooth preparation by naked eyes and a microscope,and comparison of different designs of microscopic minimally invasive tooth preparation techniques.Furthermore,a clinical protocol for microscopic minimally invasive tooth preparation based on target restorative space guide plate has been put forward and new insights on the quantity and shape of microscopic minimally invasive tooth preparation has been provided.Haiyang Yu Yuwei Zhao Junying Li Tian Luo Jing Gao Hongchen Liu Weicai Liu Feng Liu Ke Zhao Fei Liu Chufan Ma Juergen MSetz Shanshan Liang Lin Fan Shanshan Gao Zhuoli Zhu Jiefei Shen Jian Wang Zhimin Zhu Xuedong Zhou 2019International Journal of Oral Science2019,11,4:25
9SIMS U-Pb zircon age of a tuff layer in the Meishucun section, Yunnan, southwest China: Constraint on the age of the Precambrian-Cambrian boundary显示文摘Determination of the age of the Precambrian-Cambrian boundary is critical in understanding early evolution of life on Earth. SIMS U-Pb zircon analyses of the Bed 5 tuff layer of the Meishucun section were carried out closely following the guidance of cathodoluminescence images, and the majority of analyses were conducted on the oscillatory zircon grains. Thirteen measurements yield a highly reliable Concordia U-Pb age of 536.7 ± 3.9 Ma for the Bed 5 horizon. A grand mean of 206Pb/238U age of 535.2± 1.7 Ma (MSWD = 0.53) is calculated based on 13 concordant SIMS measurements of this study and 4 nano-SIMS measurements of Sawaki et al., which is the best estimate of the deposition age of the tuff layer within Bed 5 in the Meishucun section. This age has provided a robust age constraint on the significant Precambrian-Cambrian boundary strata in southern China, which independently suggested the placement of the Precambrian-Cambrian boundary at the bottom of the Xiaowaitoushan Member (Marker A).RiXiang Zhu XianHua Li XianGuang Hou YongXin Pan Fei Wang ChengLong Deng HuaiYu He 2009Science China Earth Sciences2009,52,9:24
10Methionine-dependence and combination chemotherapy on human gastric cancer cells in vitro显示文摘AIM: To elucidate whether human primary gastric cancer and gastric mucosa epithelial calls in vitro can grow normally in a rnethionine (Met) depleted environment, i.e.Met-dependence, and whether Met-depleting status can enhance the killing effect of chemotherapy on gastric cancer cells.lMETHODS: Fresh human gastric cancer and mucosal tissueswere managed to form monocellular suspensions, whichwere then cultured in the Met-free but homocysteine-containing ( MetHcy+ ) medium, with differentchemotherapeutic drugs. The proliferation of the cells wasexamined by cell counter, flow cytometry (FCM) andmicrocytotoxicity assay (MTT).RESULTS: The growth of human primary gastric cancer cellsin Met Hcy+ was suppressed, manifested by the decrease oftotal cell counts [1.46±0.42 ( x 109@L-1) in Met-Hcy+ vs .64±0.44 ( x l09@L-1) in Met+ Hcy, P<0.01], the decline inthe percentage of G0G1 phase cells (0.69±0.24 in Met-Hey+vs 0.80±0.18 in Met+ Hcy, P<0.01) and the increase of Scells(0.24±0.20inMet-Hcy+ vs 0.17 ± 0.16 in Met+ Hcy-, P< 0.01); however, gastric mucusal cells grew normally. IfMet-Hcy+ medium was used in combination withchemotherapeutic drugs, the number of surviving gastriccancer cells dropped significantly.CONCLUSION: Human primary gastric cancer cells in vitroare Met-dependent; however, gastric mucosal cells have notshown the same characteristica. Met- Hcy+ environment maystrengthen the killing effect of chemotherapy on humanprimary gastric cancer cells.Wei-Xin Cao Jing-Min Ou Xu-Feng Fei,Department of Clinical Nutrition,Shanghai Institute of Digestive Surgery,Ruijin Hospital,Shanghai Second Medical University,Shanghai 200025,China Zheng-Gang Zhu Hao-Ran Yin Min Yan Yan-Zhen Lin,Department of Surgery,Shanghai Institute of Digestive Surgery,Ruijin Hospital,Shanghai Second Medical University,Shangha 200025,China 2002World Journal of Gastroenterology2002,8,2:24
11The Chinese Society of Clinical Oncology(CSCO)clinical guidelines for the diagnosis and treatment of nasopharyngeal carcinoma显示文摘Nasopharyngeal carcinoma(NPC)is a malignant epithelial tumor originating in the nasopharynx and has a high incidence in Southeast Asia and North Africa.To develop these comprehensive guidelines for the diagnosis and management of NPC,the Chinese Society of Clinical Oncology(CSCO)arranged a multi-disciplinary team comprising of experts from all sub-specialties of NPC to write,discuss,and revise the guidelines.Based on the findings of evidencebased medicine in China and abroad,domestic experts have iteratively developed these guidelines to provide proper management of NPC.Overall,the guidelines describe the screening,clinical and pathological diagnosis,staging and risk assessment,therapies,and follow-up of NPC,which aim to improve the management of NPC.Ling-Long Tang Yu-Pei Chen Chuan-Ben Chen Ming-Yuan Chen Nian-Yong Chen Xiao-Zhong Chen Xiao-Jing Du Wen-Feng Fang Mei Feng Jin Gao Fei Han Xia He Chao-Su Hu De-sheng Hu Guang-Yuan Hu Hao Jiang Wei Jiang Feng Jin Jin-Yi Lang Jin-Gao Li Shao-Jun Lin Xu Liu Qiu-Fang Liu Lin Ma Hai-Qiang Mai Ji-Yong Qin Liang-Fang Shen Ying Sun Pei-Guo Wang Ren-Sheng Wang Ruo-Zheng Wang Xiao-Shen Wang Ying Wang Hui Wu Yun-Fei Xia Shao-Wen Xiao Kun-Yu Yang Jun-Lin Yi Xiao-Dong Zhu Jun Ma 2021Cancer Communications2021,41,11:22
12Relationship between cytokines gene polymorphism and susceptibility to hepatitis B virus intrauterine infection显示文摘Background The influences of genomic background are confirmed in more diseases. Immunologic tolerance after intrauterine infection of hepatitis B virus is considered to occur in T cells. Cytokines work effectively in eliminating virus by immune system after hepatitis B virus infection. To explore the relationship between cytokines (tumor necrosis factor-α, interferon-γ, interleukin-4 and interleukin-10), which expressed abnormal quantity in the peripheral blood to intrauterine hepatitis B virus infectious children, gene single nucleotide polymorphism (SNP) and susceptibility to hepatitis B virus intrauterine infection. Methods This is a cross sectional study of molecular clinical epidemiology. The subjects in this study were selected from outpatients of hepatitis B vaccine follow-up special clinics of our hospital in the period. According to intrant criteria, the high risk children of hepatitis B virus (HBV) intrauterine infection were divided into immune failure group (group Ⅰ); and immune effective group (group Ⅱ) and non high risk children belonged to the control group. Four gene SNP sites of TNF-α -238, IFN-γ +874, IL-4 -590 and IL-10 -1082 were determined by real-time quantitative fluorescent polymerase chain reaction (PCR). Results The significant differences of TNF-α -238 A allele frequency were found between group Ⅰ and groupⅡ (χ2=6.797,P<0.05) and between groupⅠ and the control group (χ2=9.513,P<0.05). No evident differences of TNF-α -238 A were found between group Ⅱ and control group (χ2=0.047,P>0.05); the significant differences of IFN-γ +874 A allele frequency were found between groupⅠ and groupⅡ(χ2=7.238,P<0.05), and between groupⅠ and the control group (χ2=5.199,P<0.05). No evident differences were found between groupⅡ and the control group (χ2=0.602,P>0.05); the significant differences of IL-4 -590 C/T allele frequency were not found between groupⅠand group Ⅱ(χ2=0.632,P>0.05), also groupⅠ and the control group (χ2=0.584,P>0.05), and the groupⅡ and the control group (χ2=0.004,P>0.05)respectively; The significant differences of IL-10 -1082 G allele frequency were found between groupⅡ and groupⅠ (χ2=10.359,P<0.001), and between groupⅡ and the controls (χ2=35.418,P<0.001), but the significant differences were not found between groupⅠand the control group (χ2=1.759,P>0.05). Conclusions This study suggested the possibility that the TNF-α -238 A allele and IFN-γ +874 A allele were associated with HBV intrauterine infection. There was no evident relationship between IL-4 -590 C/T allele SNP and susceptibility to HBV intrauterine infection, but the IL-10 -1082 G allele was associated with preventive efficacy to HBV intrauterine infection.ZHU Qi-rong GE Yan-ling GU Shao-qing YU Hui WANG Jian-she GU Xin-huan FEI Lin-e DONG Zuo-quan 2005Chinese Medical Journal2005,,19:21
13A Review of Seasonal Climate Prediction Research in China显示文摘The ultimate goal of climate research is to produce climate predictions on various time scales. In China, efforts to predict the climate started in the 1930 s. Experimental operational climate forecasts have been performed since the late 1950 s,based on historical analog circulation patterns. However, due to the inherent complexity of climate variability, the forecasts produced at that time were fairly inaccurate. Only from the late 1980 s has seasonal climate prediction experienced substantial progress, when the Tropical Ocean and Global Atmosphere project of the World Climate Research program(WCRP) was launched. This paper, following a brief description of the history of seasonal climate prediction research, provides an overview of these studies in China. Processes and factors associated with the climate variability and predictability are discussed based on the literature published by Chinese scientists. These studies in China mirror aspects of the climate research effort made in other parts of the world over the past several decades, and are particularly associated with monsoon research in East Asia. As the climate warms, climate extremes, their frequency, and intensity are projected to change, with a large possibility that they will increase. Thus, seasonal climate prediction is even more important for China in order to effectively mitigate disasters produced by climate extremes, such as frequent floods, droughts, and the heavy frozen rain events of South China.WANG Huijun FAN Ke SUN Jianqi LI Shuanglin LIN Zhaohui ZHOU Guangqing CHEN Lijuan LANG Xianmei LI Fang ZHU Yali CHEN Hong ZHENG Fei 2015Advances in Atmospheric Sciences2015,32,2:20
14High-intensity focused ultrasound treatment for patients with unresectable pancreatic cancer显示文摘BACKGROUND: High-intensity focused ultrasound (HIFU) is a non-invasive method of solid tissue ablation therapy. However, only a few studies have reported the effect of HIFU for unresectable pancreatic cancer. This study aimed to evaluate the clinical benefits, survival time and complications associated with the use of HIFU ablation in patients with unresectable pancreatic cancer. METHODS: Twenty-five patients with unresectable pancreatic cancer were enrolled in our study. All patients received HIFU therapy for tumors at least once. The therapeutic effects of HIFU was evaluated in terms of Karnofsky performance status (KPS) scores, pain relief, serum CA19-9, and imaging by B-US and CT before and after the therapy. We also recorded median overall survival time and complications caused by the treatment. RESULTS: In the 25 patients, KPS scores were above 60, and increased KPS was observed in 23 patients after treatment. Pain relief occurred in 23 patients. Serum CA19-9 levels were significantly reduced one month after HIFU treatment and became negative in 5 patients. B-US revealed enhanced tumor echogenicity in 13 patients and decreased tumor blood supply in 9. Tumor necrosis was confirmed by CT in 8 patients one month after HIFU treatment. The median overall survival time was 10 months, and the 1-year survival rate was 42%. No severe complications were observed after HIFU treatment. CONCLUSION: HIFU can effectively relieve pain, increase KPS, decrease tumor growth and prolong the survival time of patients with unresectable pancreatic cancer.Peng-Zhou Li, Shai-Hong Zhu, Wei He, Li-Yong Zhu, Sheng-Ping Liu, Yan Liu, Guo-Hui Wang, Fei Ye Department of General Surgery ,Department of Radiology, Third Xiangya Hospital, Central South University, Changsha 410013, China 2012Hepatobiliary & Pancreatic Diseases International2012,11,6:19
15Three-dimensional Finite Element Analysis of the Mechanical Properties of Helical Thread Connection显示文摘Conventional analytical and numerical methods for the mechanical properties of helical threads are relied on many assumptions and approximations and thus hardly yield satisfied results. A parameterized 3D finite element model of bolted joints with real helical thread geometry is established and meshed with refined hexahedral elements. The Von Mises plasticity criterion, kinematic hardening rule of materials and interfacial contacts are employed to make it possible for the suggested model be able to approach real assembly conditions. Then, the mechanical properties of bolted joints with different thread pitches, thread numbers and modular ratios are investigated, including the contact pressure distribution at joint interfaces, the axial load distribution and stress concentration in screw threads during the loading and unloading process. Simulation results indicate that the load distribution in screw threads produced by the suggested model agrees well the results from CHEN's photoelastic tests. In addition, an interesting phenomenon is found that tightening the bolt with a large preload first and then adjusting the clamping force by unloading can make the load distribution more uniform and reduce the maximum residual equivalent stress in thread roots by up to 40%. This research provides a simple and practical approach to constructing the 3D finite element model and predicting the mechanical properties of helical thread connection.YANG Guoqing HONG Jun ZHU Linbo LI Baotong XIONG Meihua WANG Fei 2013Chinese Journal of Mechanical Engineering2013,26,3:19
16Hepatitis B virus X protein promotes proliferation and upregulates TGF-β1 and CTGF in human hepatic stellate cell line,LX-2显示文摘BACKGROUND:Chronic hepatitis B virus(HBV)infection is a major cause of liver fibrosis,but the mechanisms underlying HBV-related fibrogenesis are still unknown. Although the roles of HBV X protein(HBx)remain poorly understood,it is thought to play an important role in the regulation of cellular growth and hepatocarcinogenesis. The aim of this study was to determine the role of HBx in liver fibrogenesis by studying the effect of HBx on the proliferation and expression of fibrosis-related molecules in the human hepatic stellate cell line,LX-2. METHODS:We established an in vitro co-culture system with LX-2 cells and a stable QSG7701-HBx cell line which had been transfected with the HBx gene. 3 H-TdR incorporation and flow cytometry were used to determine the effects of HBx on the proliferation of LX-2 cells. α-smooth muscle actin(α-SMA),transforming growth factor-β1(TGF-β1),transforming growth factor-βreceptor Ⅱ(TGF-βRⅡ),and connective tissue growth factor (CTGF)in LX-2 cells were analyzed by Western blotting.In addition,the expression levels of collagen typeⅠ(ColⅠ) from the co-cultured media were measured by ELISA. RESULTS: 3 H-TdR incorporation increased significantly in LX-2 cells co-cultured with QSG7701-HBx cells compared to those cultured with QSG7701-pcDNA3 and QSG7701 (non-tumorigenic human liver cell line).Cell cycle results revealed that HBx accelerated the progression of G1 to S in LX-2 cells.The expressions ofα-SMA,TGF-β1,TGF-βRⅡ,CTGF and ColⅠwere significantly increased in the co- cultures of LX-2 cells with stable QSG7701-HBx cells. CONCLUSION:These results suggest that HBx may facilitate liver fibrosis by promoting hepatic stellate cell proliferation and upregulating the expression of fibrosis- related molecules.Guang-Hui Guo,De-Ming Tan,Ping-An Zhu and Fei Liu Department of Infectious Diseases,Xiangya Hospital,Central South University,Changsha 410008,China 2009Hepatobiliary & Pancreatic Diseases International2009,8,1:17
17Loss of YTHDF2-mediated m6A-dependent mRNA clearance facilitates hematopoietic stem cell regeneration显示文摘Hu Wang Hongna Zuo Jin Liu Fei Wen Yawei Gao Xudong Zhu Bo Liu Feng Xiao Wengong Wang Gang Huang Bin Shen Zhenyu JU 2018Cell Research2018,28,10:16
18Calcium channel blockers reduce severe fever with thrombocytopenia syndrome virus (SFTSV) related fatality显示文摘Severe fever with thrombocytopenia syndrome (SFTS),an emerging tick-borne infectious disease caused by a novel phlebovirus (SFTS virus, SFTSV), was listed among the top 10 priority infectious diseases by the World Health Organization due to its high fatality of 12%-50% and possibility of pandemic transmission. Currently, effective anti-SFTSV intervention remains unavailable. Here, by screening a library of FDA-approved drugs, we found that benidipine hydrochloride, a calcium channel blocker (CCB), inhibited SFTSV replication in vitro. Benidipine hydrochloride was revealed to inhibit virus infection through impairing virus internalization and genome replication. Further experiments showed that a broad panel of CCBs, including nifedipine, inhibited SFTSV infection. The anti-SFTSV effect of these two CCBs was further an a lyzed in a humanized mouse model in which CCB treatment resulted in reduced viral load and decreased fatality rate. Importantly, by performing a retrospective clinical investigation on a large cohort of 2087 SFTS patients, we revealed that nifedipine administration enhaneed virus clearance, improved clinical recovery, and remarkably reduced the case fatality rate by >5-fold. These findings are highly valuable for developing potential host-oriented therapeutics for SFTS and other lethal acute viral infections known to be inhibited by CCBs in vitro.Hao Li Lei-Ke Zhang Shu-Fen Li Shao-Fei Zhang Wei-Wei Wan Yu-Lan Zhang Qi-Lin Xin Ke Dai Yuan-Yuan Hu Zhi-Bo Wang Xiang-Tao Zhu Yu-Jie Fang Ning Cui Pan-He Zhang Chun Yuan Qing-Bin Lu Jie-Ying Bai Fei Deng Geng-Fu Xiao Wei Liu Ke Peng 2019Cell Research2019,29,9:15
19Data mining-based detection of acupuncture treatment on juvenile myopia显示文摘OBJECTIVE:We applied data mining techniques to the study of acupuncture as a treatment for juvenile myopia,with the aim of identifying hidden patterns in the data.METHODS:Fifty patients with juvenile myopia were selected and treated with acupuncture,and data mining was used to analyze the effects of treatment and the influence of behavioral variables.Clustering analysis was used to divide myopia patients into two classifications before acupuncture treatment.Artificial neural network BP algorithm was adopted to analyze the roles of different factors in changes in diopters.An association algorithm was used to analyze factors associated with the subjective experience of acupuncture and average diopter.RESULTS:The two classification results were fully consistent with the understandings of the ophthalmic circles.The duration of using the Internet and watching TV every day was the main factor that affected vision.Acupuncture feelings and therapeutic effect have a strong correlativity.A good or above experience's score of acupuncture could slow the progression of juvenile myopia.CONCLUSION:Collecting data from patients with juvenile myopia by using data mining can extract hidden potential rules and knowledge from the research evidence.The decision support can be provided to improve the doctor's clinical acupuncture treatment effects.Xuming Yang Lingyu Xu Fei Zhong Ying Zhu 2012Journal of Traditional Chinese Medicine2012,32,3:15
20Relationship between IFN-γ gene polymorphism and susceptibility to intrauterine HBV infection显示文摘瞄准:为了由学习在 IFN-gamma 基因多型性,包括的 IFN-gamma+874A/T 单个核苷酸多型性(SNP ) 和 CA 之间的关系探索孩子的危险性到子宫内的 HBV 感染,重复微卫星多型性和子宫内的 HBV 感染。方法:在 IFN-gamma+874A/T 单个核苷酸多型性的 TaqMan 荧光聚合酶链反应在子宫内的 HBV 感染组被测试(组我) 并且孩子们组织的正常免疫者(组 II ) 。毛状的电气泳动在上述二个组被执行到试金 IFN-gamma CA 重复微卫星多型性。结果:AA 的频率,在并且 TT 遗传型在感染组织的子宫内的 HBV 是 67.4% , 19.6% 和 13.0% ,并且 45.2% , 30.1% 和 24.7% 分别地在正常有免疫力的孩子组织。有效差量在在二个组之间的 IFN-gamma+874 遗传型的频率分发被发现(chi2 = 5.102, P = 0.02389 ) 。在子宫内的 HBV 感染组, AA 遗传型比在正常免疫者组织是更普通的。IFN-gamma+874A 等位基因的频率在子宫内的 HBV 感染组是 77.17% ,并且 60.27% 在正常有免疫力的孩子组织。在子宫内的 HBV 感染组, IFN-gamma+874A 等位基因比在正常免疫者组织是更普通的。有效差量在在二个组之间的频率分发被发现(chi2 = 7.238, P = 0.02389,或 = 2.228, 95% CI = 1.244-3.992 ) 。(CA12 ) IFN-gamma CA 微卫星多型性的 +/(CA12 )+ 在子宫内的 HBV 感染组是 11.90% , 26.47% 在正常有免疫力的孩子组织。有效差量在在二个组之间的频率分发被发现(chi2 = 5.64, P = 0.0176 ) 。IFN-gamma CA 重复的频率在子宫内的 HBV 感染组是 25% , 43.38% 在正常有免疫力的孩子组织。IFN-gamma CA 重复的频率比在正常免疫者组织是在子宫内的 HBV 感染组的更少。有效差量在在二个组之间的频率分发被发现(chi2 = 7.548, P = 0.0060 ) 。结论:在 IFN-gamma+874A/T SNP 和子宫内的 HBV 感染之间以及在 IFN-gamma CA 微卫星多型性和子宫内的 HBV 感染之间有一种关系。IFN-gamma 基因多型性可能在决定个人的危险性到子宫内的 HBV 感染是重要的。Hui Yu Qi-Rong Zhu Shao-Qing Gu Lin-E Fei 2006World Journal of Gastroenterology2006,12,18:14
返回顶部 每页显示:
共45页 首页 上一页 第1页 下一页 末页 /45 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费