期刊文献+
共找到750篇文章
< 1 2 38 >
每页显示 20 50 100
Plasma levels of omentin-1 and visfatin in senile patients with coronary heart disease and heart failure 被引量:38
1
作者 Xiu-Hua Wang Ling-Zhi Dou +1 位作者 Can Gu Xiao-Qing Wang 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第1期55-62,共8页
Objective:To investigate the alteration of plasma levels of omentin-1 and visfatin in elderly patients with coronary heart disease(CHD)and heart failure.Methods:Plasma omentin-1 and visfatin levels were measured in 90... Objective:To investigate the alteration of plasma levels of omentin-1 and visfatin in elderly patients with coronary heart disease(CHD)and heart failure.Methods:Plasma omentin-1 and visfatin levels were measured in 90 subjects(29 stable angina pectoris(SAP)cases,30 unstable angina pectoris(UAP)cases and 31 age-and sex-matched healthy controls(age≥60 years)by enzyme-linked immunosorbent assay methods.According to the New York Heart Association classification.59 CHDs were divided into three groups:functional I class,11 cases;functional II/III class,36 cases;and functional IV class,12 cases.Results:The plasma level of omentin-1in CHO patients was significantly lower than thai of the control group.Otnenlin-lin SAP group and UAP group were significantly lower compared to the control group(there was no statistical significance between UAP group and SAP group;P>0.05).The plasma level of visfatin in CHD patients was significandy higher than that of the control group.Similarly,visfatin in SAP group and UAP group were all significantly higher compared to the control group,while there was no statistical significance between UAP group,and SAP group.The plasma omentin-1 level was negatively correlated with SBP(r=-0.264,P<0.05),positively correlated with HDL-c level(r=0.271,P<0.05);the plasma visfatin level was positively correlated with TC(r=0.292,P<0.05),negatively correlated with HDL-c level(r=-0.266,P<0.05).There was a negative correlation between plasma omentin-1 and visfatin levels(r=-0.280,P<0.05).Moreover,multiple linear stepwise regression analysis showed that omentin-1 and visfatin levels might be affected by HDL-c level.Logistic regression analysis showed that visfatin could be an independent risk factor of CHD.Conclusions:Decreased levels of omentin-1 and increased levels of visfatin may be involved in the occurrence and development of CHD.Omentin-1 and visfatin,independently,may be protective and pro-inflammatory cytokines.Additionally,both omentin-1 and visfatin may be related to lipid metabolism.Visfatin may b 展开更多
关键词 Coronary heart disease Omenlin-1 VISFATIN NYHA class Stable ANGINA PECTORIS Unstable ANGINA PECTORIS
下载PDF
灰色区间预测的新方法 被引量:16
2
作者 宋中民 《武汉理工大学学报(交通科学与工程版)》 北大核心 2002年第6期796-799,共4页
针对具有离散程序大且总体趋势增长的一类序列 ,给出了一种灰色区间预测的新方法 .该方法是先讨论序列的级比 ,对级比选取一些不同的阈值 ,根据不同的阈值对原始数据列进行分组 ,然后对各个分组序列分别建立非等时距的灰色模型 。
关键词 级比 非等时距 GM(1 1)模型
下载PDF
射频识别防碰撞Q算法的分析及改进 被引量:7
3
作者 韩振伟 宋克非 《计算机工程与设计》 CSCD 北大核心 2011年第7期2314-2318,共5页
为了减少射频识别系统多个标签防碰撞过程中所消耗的动态功耗,通过对RFID领域超高频频段EPCglobal Class-1Gen-2标准中的标签识别层所采用的防碰撞技术及相关指令的分析,在其基础上对Q算法提出改进方案。该方案使用稳定缓变的帧长度来... 为了减少射频识别系统多个标签防碰撞过程中所消耗的动态功耗,通过对RFID领域超高频频段EPCglobal Class-1Gen-2标准中的标签识别层所采用的防碰撞技术及相关指令的分析,在其基础上对Q算法提出改进方案。该方案使用稳定缓变的帧长度来适应现场标签数量,使帧长度保持在最优值,减小标签内部门电路翻转频率,从而降低了标签防碰撞过程中总动态功耗81.8%。仿真实验结果表明,改进后的Q算法帧长度调整频率低于改进前的Q算法帧长度调整频率。 展开更多
关键词 防碰撞 Q算法 EPCGLOBAL class-1 Gen-2标准 射频识别 标签
下载PDF
一个功率可控型蓝牙CMOS功率放大器设计 被引量:6
4
作者 罗志聪 林伟 +1 位作者 孙奇燕 黄世震 《微电子学与计算机》 CSCD 北大核心 2009年第6期202-205,共4页
基于0.18μm CMOS工艺,设计出一个适用于class1蓝牙系统的高效率的差分E类功率放大器.驱动级采用自偏置Cascode结构,输入和级间匹配均片内完成,实现高集成度.在电源电压1.8V,温度60℃,输入信号0dBm条件下,仿真结果表明,该系统具有最大... 基于0.18μm CMOS工艺,设计出一个适用于class1蓝牙系统的高效率的差分E类功率放大器.驱动级采用自偏置Cascode结构,输入和级间匹配均片内完成,实现高集成度.在电源电压1.8V,温度60℃,输入信号0dBm条件下,仿真结果表明,该系统具有最大输出功率24.1dBm,PAE为57.9%,二次谐波分量为-40.05dBm,输出电压驻波比小于6∶1.采用间接闭环控制环路控制输出级的电源电压,实现了输出功率的步进为2dBm控制.整个系统最终实现低成本、高集成度. 展开更多
关键词 CMOS class1 差分E类 自偏置型Cascode 功率控制
下载PDF
Dolphin软件分析自锁托槽矫治青少年安氏Ⅱ类1分类错颌患者颞下颌关节的变化
5
作者 黄珠妹 陈娟娟 +2 位作者 袁观宝 谢晓梅 陈昕 《国际医药卫生导报》 2024年第2期292-296,共5页
目的探讨应用Dolphin软件分析自锁托槽矫治青少年安氏Ⅱ类1分类错颌患者颞下颌关节的变化。方法选取2020年12月至2022年3月中国人民解放军陆军第七十三集团军医院口腔科就诊的110例青少年安氏Ⅱ类1分类错颌患者作为研究对象进行回顾性研... 目的探讨应用Dolphin软件分析自锁托槽矫治青少年安氏Ⅱ类1分类错颌患者颞下颌关节的变化。方法选取2020年12月至2022年3月中国人民解放军陆军第七十三集团军医院口腔科就诊的110例青少年安氏Ⅱ类1分类错颌患者作为研究对象进行回顾性研究,其中男48例,女62例,年龄(12.21±1.02)岁。所有患者均采用自锁托槽矫治器矫正治疗,矫正前后拍摄大视野锥形束CT(CBCT),导入Dolphin软件进行定点测量,分析患者矫正前、矫正两年后颞下颌关节变化情况。采用配对t检验。结果矫正后,轴状面的左侧髁突内外径(16.42±0.43)mm、右侧髁突内外径(16.10±0.88)mm、左侧前后径(8.62±0.80)mm、右侧前后径(8.96±1.19)mm、左侧颞下颌关节半径(49.36±1.25)mm、右侧颞下颌关节半径(49.06±1.20)mm、左侧髁突高度(3.44±0.23)mm、右侧髁突高度(3.85±0.30)mm均大于矫正前(t=2.151、2.350、6.914、3.250、2.393、2.188、1.984、9.354,均P<0.05);矫正后,矢状位的左侧关节前间隙(2.30±0.41)mm、右侧关节前间隙(2.54±0.52)mm、左侧关节上间隙(2.89±0.50)mm、右侧关节上间隙(3.04±1.02)mm、左侧关节后间隙(2.58±0.49)mm、右侧关节后间隙(2.46±0.53)mm、左侧髁突宽(9.06±0.99)mm、右侧髁突宽(10.06±1.36)mm均大于矫正前(t=2.231、3.635、1.996、2.281、19.761、17.790、2.076、3.286,均P<0.05);矫正后,冠状位的左侧关节内间隙(2.86±0.78)mm、右侧关节内间隙(2.77±0.63)mm、左侧关节上间隙(3.04±0.52)mm、右侧关节上间隙(3.30±0.98)mm、左侧关节外间隙(3.64±1.00)mm、右侧关节外间隙(3.88±1.15)mm、左侧髁突宽(15.00±0.82)mm,右侧髁突宽(15.12±0.99)mm均大于矫正前(t=2.101、2.183、6.097、5.189、2.073、2.292、3.020、2.639,均P<0.05)。结论经Dolphin软件分析,青少年安氏Ⅱ类1分类错颌患者采用自锁式托槽式矫治器治疗,颞下颌关节参数发生一定变化。 展开更多
关键词 错颌 安氏Ⅱ类1分类 Dolphin软件 自锁托槽矫治器 颞下颌关节 下颌骨
下载PDF
Effect of Danhong injection on expressions of macrophage scavenger receptor 1 and sub-family A member 1 in human U937 cells 被引量:6
6
作者 Xianming Su Wei Yang Xiaowen Zhi 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第3期384-387,共4页
OBJECTIVE: To study the effects of Danhong injec- tion (DHI) on expression of the macrophage scaven- ger receptor 1 (MSR1) and ATP-binding cassette, sub-family A member 1 (ABCA1) genes, which en- code scavenger... OBJECTIVE: To study the effects of Danhong injec- tion (DHI) on expression of the macrophage scaven- ger receptor 1 (MSR1) and ATP-binding cassette, sub-family A member 1 (ABCA1) genes, which en- code scavenger receptor-A I (SR-AI) and ATP-bind- ing cassette transporter 1 (ABCA1), respectively, as a potential anti-atherosclerotic mechanism. METHODS: Human U937 cells were stimulated by in- cubation with 100 nM phorbo112-myristate 13-ace- tate (PMA) for 48 h.These stimulated, monocyte-like cells were then incubated for 24 h with 50 mg/L oxi- dized low-density lipoprotein (ox-LDL, to induce foam cell formation), together with a liver X recep- tor (LXR) agonist or with different DHI concentra- tions. MSR1 and ABCA1 mRNA levels were mea- sured by fluorescence-based quantitative PCR. RESULTS: Compared with control cells (which re- ceived only ox-LDL), cells treated with both ox-LDL and 10 IJmol/L LXR agonist showed lower MSR1 ex-pression (but this effect was not statistically signifi- cant, P〉0.05) and higher ABCA1 expression (P〈 0.01). Cells that received ox-LDL and 3 mL/L DHI possessed higher MSR1 mRNA levels than the con- trols, whereas cells treated with ox-LDL and higher DHI concentrations (10, 30 or 60 mL/L) showed low- er MSR1 expression levels (but the differences ob- served between DHI concentration groups were not statistically significant, P〉0.05). ABCA1 expression in cells treated with ox-LDL and 3, 10 or 30 mL/L DHI was higher than in the control cells, and increased with increasing DHI concentration (P〈0.05). ABCA1 expression in cells treated with ox-LDL and the highest DHI concentration tested (60 mL/L) was not significantly different from that in the controls. ABCA1 mRNA levels in cells treated with ox-LDL and DHI were similar to, or lower than, those in cells treated with ox-LDL and the LXR agonist. CONCLUSION: DHI does not affect MSR1 mRNA lev- els in ox-LDL-treated U937 cells. However, at certain concentrations (10 and 30 m 展开更多
关键词 Receptors scavengers class A ATP-binding cassette transporters Cholesterol me-tabolism U937 cells Danhong injection
原文传递
Coupled single-cell and bulk RNA-seq analysis reveals the engulfment role of endothelial cells in atherosclerosis
7
作者 Jianxiong Xu Jinxuan Wang +7 位作者 Hongping Zhang Yidan Chen Xiaojuan Zhang Ying Zhang Ming Xie Jun Xiao Juhui Qiu Guixue Wang 《Genes & Diseases》 SCIE CSCD 2024年第5期442-455,共14页
The clearance of apoptotic cell debris,containing professional phagocytosis and non-professional phagocytosis,is essential for maintaining the homeostasis of healthy tissues.Here,we discovered that endothelial cells c... The clearance of apoptotic cell debris,containing professional phagocytosis and non-professional phagocytosis,is essential for maintaining the homeostasis of healthy tissues.Here,we discovered that endothelial cells could engulf apoptotic cell debris in atherosclerotic plaque.Single-cell RNA sequencing(RNA-seq)has revealed a unique endothelial cell subpopulation in atherosclerosis,which was strongly associated with vascular injury-related pathways.Moreover,integrated analysis of three vascular injury-related RNA-seq datasets showed that the expression of scavenger receptor class B type 1(SR-B1)was up-regulated and specifically enriched in the phagocytosis pathway under vascular injury circumstances.Single-cell RNA-seq and bulk RNA-seq indicate that SR-B1 was highly expressed in a unique endothelial cell subpopulation of mouse aorta and strongly associated with the reorganization of cellular adherent junctions and cytoskeleton which were necessary for phagocytosis.Furthermore,SR-B1 was strongly required for endothelial cells to engulf apoptotic cell debris in atherosclerotic plaque of both mouse and human aorta.Overall,this study demonstrated that apoptotic cell debris could be engulfed by endothelial cells through SR-B1 and associated with the reorganization of cellular adherent junctions and cytoskeleton. 展开更多
关键词 Apoptotic cell debris ATHEROSCLEROSIS Endothelial engulfment Single-cell RNA sequencing Scavenger receptor class B type 1
原文传递
New insights into renal lipid dysmetabolism in diabetic kidney disease 被引量:6
8
作者 Alla Mitrofanova George Burke +1 位作者 Sandra Merscher Alessia Fornoni 《World Journal of Diabetes》 SCIE 2021年第5期524-540,共17页
Lipid dysmetabolism is one of the main features of diabetes mellitus and manifests by dyslipidemia as well as the ectopic accumulation of lipids in various tissues and organs,including the kidney.Research suggests tha... Lipid dysmetabolism is one of the main features of diabetes mellitus and manifests by dyslipidemia as well as the ectopic accumulation of lipids in various tissues and organs,including the kidney.Research suggests that impaired cholesterol metabolism,increased lipid uptake or synthesis,increased fatty acid oxidation,lipid droplet accumulation and an imbalance in biologically active sphingolipids(such as ceramide,ceramide-1-phosphate and sphingosine-1-phosphate)contribute to the development of diabetic kidney disease(DKD).Currently,the literature suggests that both quality and quantity of lipids are associated with DKD and contribute to increased reactive oxygen species production,oxidative stress,inflammation,or cell death.Therefore,control of renal lipid dysmetabolism is a very important therapeutic goal,which needs to be archived.This article will review some of the recent advances leading to a better understanding of the mechanisms of dyslipidemia and the role of particular lipids and sphingolipids in DKD. 展开更多
关键词 Diabetes LIPIDS Free fatty acids ATP-binding cassette transporters sub-class A Sterol-O-acyltransferase 1 CD36 SPHINGOLIPIDS Sphingomyelin phosphodiesterase acid-like 3b Diabetic kidney disease
下载PDF
Characterization of Class 1 Integron Gene Cassettes among Clinical Bacteria Isolated from One Large Hospital in Northern China 被引量:5
9
作者 CHEN Xia LI Gui Xi +4 位作者 ZHANG Hong YUAN Min HOU Xiao Ping YU Hui Lan LI Juan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第12期1003-1007,共5页
The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 int... The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 integrons containing gene cassettes widely distributed among gram negative clinical isolates was observed. We find that the class 1 integron showed positive correlation with multidrug resistance phenotype of gram negative bacteria. In addition, we find that isolates belonged to one species harbored different types of gene cassette arrays, while same types of gene cassette arrays were observed in different species of isolates. The diversity of gene cassette arrays among the isolates indicated the complexity of multidrug resistance in clinical isolates in northern China. 展开更多
关键词 gene Characterization of class 1 Integron Gene Cassettes among Clinical Bacteria Isolated from One Large Hospital in Northern China
下载PDF
Role of sphingosine 1-phosphate in anti-atherogenic actions of high-density lipoprotein 被引量:4
10
作者 Koichi Sato Fumikazu Okajima 《World Journal of Biological Chemistry》 CAS 2010年第11期327-337,共11页
The reverse cholesterol transport mediated by high-density lipoprotein (HDL) is an important mechanism for maintaining body cholesterol, and hence, the crucial anti-atherogenic action of the lipoprotein. Recent studie... The reverse cholesterol transport mediated by high-density lipoprotein (HDL) is an important mechanism for maintaining body cholesterol, and hence, the crucial anti-atherogenic action of the lipoprotein. Recent studies, however, have shown that HDL exerts a variety of anti-inflammatory and anti-atherogenic actions independently of cholesterol metabolism. The present review provides an overview of the roles of sphingosine 1-phosphate (S1P)/S1P receptor and apolipoprotein A-I/scavenger receptor class B type I systems in the anti-atherogenic HDL actions. In addition, the physiological significance of the existence of S1P in the HDL particles is discussed. 展开更多
关键词 High-density lipoprotein Sphingosine 1-phosphate Scavenger receptor class B type I Anti-atherogenic actions
下载PDF
最大度是4的可平面图是第一类图的充分条件 被引量:4
11
作者 倪伟平 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第3期85-91,共7页
运用Discharge方法证明:最大度是4,且满足下列条件之一的可平面图G是第一类的.(1)G中不含长度为4至9的圈;(2)G中不含4-圈和5-圈,且任意两个3-面不关联于同一个顶点;(3)G中不含长度在5和8之间的圈,且任意两个3-圈,任意两个4-圈不关联于... 运用Discharge方法证明:最大度是4,且满足下列条件之一的可平面图G是第一类的.(1)G中不含长度为4至9的圈;(2)G中不含4-圈和5-圈,且任意两个3-面不关联于同一个顶点;(3)G中不含长度在5和8之间的圈,且任意两个3-圈,任意两个4-圈不关联于同一个顶点;(4)围长不小于4,G中不含有弦的8-圈,且任意两个4-面不关联于同一个顶点. 展开更多
关键词 平面图 边染色 最大度 第一类图
下载PDF
Survivin、BRCA1及class Ⅲ β-tubulin在非小细胞肺癌组织中的表达及与紫杉醇耐药的关系 被引量:3
12
作者 周正仕 廖小方 +1 位作者 郑勤红 何慧娟 《肿瘤学杂志》 CAS 2012年第11期806-810,共5页
[目的]探讨Survivin、BRCA1及class Ⅲβ-tubulin蛋白在非小细胞肺癌(NSCLC)中的表达及与紫杉醇耐药的关系。[方法]应用免疫组织化学法检测64例NSCLC患者Survivin、BRCA1及class Ⅲβ-tubulin蛋白的表达;给予紫杉醇为基础的化疗方案,分... [目的]探讨Survivin、BRCA1及class Ⅲβ-tubulin蛋白在非小细胞肺癌(NSCLC)中的表达及与紫杉醇耐药的关系。[方法]应用免疫组织化学法检测64例NSCLC患者Survivin、BRCA1及class Ⅲβ-tubulin蛋白的表达;给予紫杉醇为基础的化疗方案,分析上述蛋白表达与紫杉醇化疗敏感性的关系。[结果]Survivin阳性与class Ⅲβ-tubulin阳性患者对紫杉醇方案治疗的有效率(RR)分别低于Survivin阴性患者(27.8%vs71.4%,P<0.05)与class Ⅲβ-tubulin阴性患者(23.5%vs73.3%,P<0.01);而BRCA1阳性患者对紫杉醇方案治疗的RR高于BRCA1阴性患者(60.0%vs31.0%,P<0.05)。多因素分析表明classⅢβ-tubulin是NSCLC紫杉醇治疗无进展生存期(PFS)的独立影响因素(χ2=4.852,P=0.027),分期是与总生存期(OS)相关的独立影响因素(χ2=4.105,P=0.035)。[结论]NSCLC患者Survivin、class Ⅲβ-tubulin蛋白表达阳性及BRCA1蛋白表达阴性预示对紫杉醇治疗相对不敏感。 展开更多
关键词 SURVIVIN BRCA1 class Β-TUBULIN 肺肿瘤 紫杉醇 耐药
原文传递
照明用LED的辐射安全 被引量:2
13
作者 杨樾 《中国照明电器》 2008年第12期31-33,共3页
LED照明产品的快速发展,对相应的LED照明产品检测技术有了新的要求。本文介绍了现行的欧洲关于检测照明用LED产品的辐射安全的CTL决议要求;IEC60825-1(ED1.2)标准中与照明用LED产品的辐射安全相关的1类和1M类的定义、分类原则和判断方法... LED照明产品的快速发展,对相应的LED照明产品检测技术有了新的要求。本文介绍了现行的欧洲关于检测照明用LED产品的辐射安全的CTL决议要求;IEC60825-1(ED1.2)标准中与照明用LED产品的辐射安全相关的1类和1M类的定义、分类原则和判断方法;以及根据IEC60825-1(ED1.2)标准要求的计算1类或1M类的限值计算方法,为广大检测单位和厂家提供参考。 展开更多
关键词 LED 照明 辐射1 1M类
原文传递
Continuous activation of polymorphonuclear myeloid-derived suppressor cells during pregnancy is critical for fetal development 被引量:3
14
作者 Mengyu Shi Ziyang Chen +12 位作者 Meiqi Chen Jingping Liu Jing Li Zhe Xing Xiaogang Zhang Shuaijun Lv Xinyao Li Shaowen Zuo Shi Feng Ying Lin Gang Xiao Liping Wang Yumei He 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2021年第7期1692-1707,共16页
The maternal immune system is vital in maintaining immunotolerance to the semiallogeneic fetus for a successful pregnancy.Although studies have shown that myeloid-derived suppressor cells(MDSCs)play an important role ... The maternal immune system is vital in maintaining immunotolerance to the semiallogeneic fetus for a successful pregnancy.Although studies have shown that myeloid-derived suppressor cells(MDSCs)play an important role in maintaining feto-maternal tolerance,little is known about the role of MDSCs in pregnancies with intrauterine growth retardation(IUGR).Here,we reported that the activation of polymorphonuclear myeloid-derived suppressor cells(PMN-MDSCs)during pregnancy was closely associated with fetal growth.In humans,class E scavenger receptor 1(SR-E1),a distinct marker for human PMN-MDSCs,was used to investigate PMN-MDSC function during pregnancy.Continuous activation of SR-E1+PMN-MDSCs was observed in all stages of pregnancy,accompanied by high cellular levels of ROS and arginase-1 activity,mediated through STAT6 signaling.However,SR-E1+PMN-MDSCs in pregnancies with IUGR showed significantly lower suppressive activity,lower arginase-1 activity and ROS levels,and decreased STAT6 phosphorylation level,which were accompanied by an increase in inflammatory factors,compared with those in normal pregnancies.Moreover,the population of SR-E1+PMN-MDSCs was negatively correlated with the adverse outcomes of newborns from pregnancies with IUGR.In mice,decreases in cell population,suppressive activity,target expression levels,and STAT6 phosphorylation levels were also observed in the pregnancies with IUGR compared with the normal pregnancies,which were rescued by the adoptive transfer of PMN-MDSCs from pregnant mice.Interestingly,the growth-promoting factors(GPFs)secreted by placental PMN-MDSCs in both humans and mice play a vital role in fetal development.These findings collectively support that PMN-MDSCs have another new role in pregnancy,which can improve adverse neonatal outcomes. 展开更多
关键词 Polymorphonuclear myeloid-derived suppressor cells class E scavenger receptor 1 IMMUNOTOLERANCE
原文传递
Stress increases MHC-I expression in dopaminergic neurons and induces autoimmune activation in Parkinson’s disease 被引量:3
15
作者 Bao-Yan Wang Yong-Yi Ye +6 位作者 Chen Qian Hong-Bo Zhang Heng-Xu Mao Long-Ping Yao Xiang Sun Guo-Hui Lu Shi-Zhong Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第12期2521-2527,共7页
The expression of major histocompatibility complex class I(MHC-I),a key antigen-presenting protein,can be induced in dopaminergic neurons in the substantia nigra,thus indicating its possible involvement in the occurre... The expression of major histocompatibility complex class I(MHC-I),a key antigen-presenting protein,can be induced in dopaminergic neurons in the substantia nigra,thus indicating its possible involvement in the occurrence and development of Parkinson’s disease.However,it remains unclear whether oxidative stress induces Parkinson’s disease through the MHC-I pathway.In the present study,polymerase chain reaction and western blot assays were used to determine the expression of MHC-I in 1-methyl-4-phenylpyridinium(MPP+)-treated SH-SY5Y cells and a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced Parkinson’s disease mouse model.The findings revealed that MHC-I was expressed in both models.To detect whether the expression of MHC-I was able to trigger the infiltration of cytotoxic T cells,immunofluorescence staining was used to detect cytotoxic cluster of differentiation 8(CD8)+T cell infiltration in the substantia nigra of MPTP-treated mice.The results indicated that the presentation of MHC-I in dopaminergic neurons was indeed accompanied by an increase in the number of CD8+T cells.Moreover,in MPTP-induced Parkinson’s disease model mice,the genetic knockdown of endogenous MHC-I,which was caused by injecting specific adenovirus into the substantia nigra,led to a significant reduction in CD8+T cell infiltration and alleviated dopaminergic neuronal death.To further investigate the molecular mechanisms of oxidative stress-induced MHC-I presentation,the expression of PTEN-induced kinase 1(PINK1)was silenced in MPP+-treated SH-SY5Y cells using specific small interfering RNA(siRNA),and there was more presentation of MHC-I in these cells compared with control siRNA-treated cells.Taken together,MPP+-/MPTP-induced oxidative stress can trigger MHC-I presentation and autoimmune activation,thus rendering dopaminergic neurons susceptible to immune cells and degeneration.This may be one of the mechanisms of oxidative stress-induced Parkinson’s disease,and implies the potential neuroprotective role of PINK1 in oxida 展开更多
关键词 antigen presentation AUTOIMMUNE CD8+T cell dopaminergic neuron major histocompatibility complex class I mitochondria NEUROINFLAMMATION oxidative stress Parkinson’s disease PINK1
下载PDF
Detection of class 1 integron in Acinetobacter baumannii isolates collected from nine hospitals in Turkey 被引量:3
16
作者 Aysegül Copur Cicek Azer Ozad Düzgün +10 位作者 Aysegül Saral Tuba Kayman Zeynep Cizmeci Pervin Ozlem Balci Tuba Dal Mehmet Firat Ismail Tosun Yasemin Ay Alitntop Ahmet Caliskan Yelda Yazici Cemal Sandalli 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第9期743-747,共5页
Objective:To investigate the antibiotic resistance genes inserted into class I and class 2integrons in Acinetobacler baumannii[A.baumannii)isolates obtained from nine different cities in Turkey.Methods:A collection of... Objective:To investigate the antibiotic resistance genes inserted into class I and class 2integrons in Acinetobacler baumannii[A.baumannii)isolates obtained from nine different cities in Turkey.Methods:A collection of 281 A.baumannii clinical isolates were collected from nine diferenl state hospitals in Turkey and were confirmed as A.baumannU by conventional biochemical,API testing and bla_(-OXA-51)specific PCR.The isolates were examined by PCR for existence of class I and2 integron gene cassettes.Results:They were characterized by antimicrobial susceptibility testing and the highest resistance rates were determined for piperacillin(90.03%),ciprofloxacin(87.54%),cefepime and trimethoprim/sulfamethoxazole(81.13%).The lowest resistance rates was for cefotaxime(3.55%).class 1 integrons were detected in 6.4%(18/281)of A.baumannii strains and no class 2 integron was detected.The gene casselles of class 1 inlegrons AacCI-AAC(3)l-aadAI,AacCI-aadA1,AAC(3)-I,AAC(3)-I-AAC(3)-I-aadA1,TEM-1.AAC(3)-I-aadA1-AAC(3)-I-AAC(3)-I,AAC(3)-I-AAC(3)-I-AAC(3)-I-aadA1,AAC(3)-I-aadA1,AAC(3)-I-AAC(3)-I,AAC(3)-I-aadA1-AAC(3)-I-aadA1,AAC(3)-I-AAC(3)-I-aadA1-AAC(3)-I-aadA1 were detected in eighteen strains.The aac genes family were most frequently found integrated into the class 1 inlegrons and it was followed by aadA genes and TEM-1 genes.Conclusions:This is an extensive study on the distribulion of class 1 integron among A.baumannii in Turkey.In addition to these,two new alleles were observed.Their percentage rates of similarity to other cassettes are 95%aadA1(TK A18)and 89%,aadA 1(ANKA3). 展开更多
关键词 Acinetobacter baumannii class 1 integron Gene cassette RESISTANCE
下载PDF
最大度是5的可平面图是第一类的充分条件 被引量:3
17
作者 周正同 苗连英 《山东大学学报(理学版)》 CAS CSCD 北大核心 2010年第4期24-26,30,共4页
运用Discharge方法以及临界图的一些重要性质证明了:每个最大度为5且不含四圈五圈的简单平面图的边色数等于5,即这样的平面图是第一类的。给出了最大度为5的平面图分类的一个特征刻画。
关键词 平面图 边染色 最大度 第一类图
原文传递
RFID C1G2协议特性解析及在商品管理中的应用 被引量:1
18
作者 文燕 《现代电子技术》 2009年第9期86-88,96,共4页
EPCglobal推出的EPC Class-1 Gen-2接口协议,相对第一代协议,使超高频射频识别(UHF RFID)系统性能有了显著提高,适应标签低处理能力、低功耗和低成本的要求,并成为了ISO 18000-6C标准。对该协议特性进行了详细解析,并分析了其在商品管... EPCglobal推出的EPC Class-1 Gen-2接口协议,相对第一代协议,使超高频射频识别(UHF RFID)系统性能有了显著提高,适应标签低处理能力、低功耗和低成本的要求,并成为了ISO 18000-6C标准。对该协议特性进行了详细解析,并分析了其在商品管理中的应用,这些特点包括了标签存储空间、安全性、防冲突算法、读写器操作模式、通信方法及全球性等。 展开更多
关键词 RFID EPC class-1 Gen-2 低功耗 商品管理
下载PDF
UHF RFID标签基带处理器的ASIC设计 被引量:2
19
作者 乔文 冯全源 《微电子学》 CAS CSCD 北大核心 2012年第2期164-167,172,共5页
提出了一款基于EPC Class1 Generation2协议的UHF RFID标签基带处理器。考虑到工作距离是无源标签的一个重要指标,要提高工作距离,就要降低标签功耗,采取了一系列低功耗措施,如2.56MHz和1.28MHz的双时钟策略、增加单元开关功能以及使用... 提出了一款基于EPC Class1 Generation2协议的UHF RFID标签基带处理器。考虑到工作距离是无源标签的一个重要指标,要提高工作距离,就要降低标签功耗,采取了一系列低功耗措施,如2.56MHz和1.28MHz的双时钟策略、增加单元开关功能以及使用异步计数器等。设计采用TSMC 0.18μm工艺,工作电压为1.8V,功耗为6.4μW,版图尺寸为415μm×398μm。采用Xilinx的FPGA开发平台进行验证,测试结果满足C1G2协议要求。 展开更多
关键词 射频识别 标签 基带处理器 EPC class1 Generation2协议
下载PDF
基于EPC Class-1 Gen-2标准的防冲突算法与改进 被引量:1
20
作者 张瑞子 南琳 +1 位作者 胡琨元 田景贺 《计算机工程》 CAS CSCD 北大核心 2009年第2期24-26,共3页
针对RFID读写器识别多标签过程中出现的冲突问题,研究并实现了EPC Class-1 Gen-2标准中的防冲突算法,即时隙随机算法(SR算法),同时针对SR算法的不足提出改进算法。改进算法采用不避让冲突时隙的处理方式,降低了由时隙的随机选取所导致... 针对RFID读写器识别多标签过程中出现的冲突问题,研究并实现了EPC Class-1 Gen-2标准中的防冲突算法,即时隙随机算法(SR算法),同时针对SR算法的不足提出改进算法。改进算法采用不避让冲突时隙的处理方式,降低了由时隙的随机选取所导致的标签间冲突的概率。实验结果证明,改进后的算法在通信次数和吞吐率方面均优于原算法,有效提高标签识别效率。 展开更多
关键词 防冲突 EPC class-1 Gen-2标准 ALOHA算法 标签识别
下载PDF
上一页 1 2 38 下一页 到第
使用帮助 返回顶部