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一种快速纯化蛋白的电洗脱方法 被引量:20
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作者 景巍 王转花 《生物技术》 CAS CSCD 2004年第2期30-31,共2页
以TB2 4kDa蛋白为例介绍了一种快速纯化蛋白的电洗脱方法。根据作者实验室先前建立的提取苦荞种子蛋白的方法制备TB2 4kDa蛋白粗提物 ,利用阴离子交换层析和改进的电泳洗脱方法对其进行纯化。结果显示 :经改进的电洗脱纯化 ,1mg粗蛋白... 以TB2 4kDa蛋白为例介绍了一种快速纯化蛋白的电洗脱方法。根据作者实验室先前建立的提取苦荞种子蛋白的方法制备TB2 4kDa蛋白粗提物 ,利用阴离子交换层析和改进的电泳洗脱方法对其进行纯化。结果显示 :经改进的电洗脱纯化 ,1mg粗蛋白可以回收得到 15 0 μg左右的目的蛋白 ,回收率为 15 .32 % ,纯化效果较理想。 展开更多
关键词 纯化 蛋白 电洗脱 TB24 kda SDS-PAGE 生物化学
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基于非线性特征提取和SVM的人脸识别算法 被引量:14
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作者 孙大瑞 吴乐南 《电子与信息学报》 EI CSCD 北大核心 2004年第2期307-311,共5页
传统的PCA或LDA都是从像素的二阶依赖上考虑的,对于多像素之间的依赖性或像素的高阶关系不敏感。该文利用核函数方法提取像素高阶相关,并与线性SVM相结合来进行人脸识别。从Yale人脸库上的实验结果可以看出,非线性特征提取是很有效的,并... 传统的PCA或LDA都是从像素的二阶依赖上考虑的,对于多像素之间的依赖性或像素的高阶关系不敏感。该文利用核函数方法提取像素高阶相关,并与线性SVM相结合来进行人脸识别。从Yale人脸库上的实验结果可以看出,非线性特征提取是很有效的,并且SVM分类器的性能优于最近邻分类器。 展开更多
关键词 非线性特征提取 SVM 人脸识别 KPCA kda
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花生蛋白组分及其亚基含量近红外分析检测方法 被引量:11
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作者 赵思梦 于宏威 +4 位作者 高冠勇 陈宁 王博妍 王强 刘红芝 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2021年第3期912-917,共6页
花生球蛋白、伴花生球蛋白及亚基含量显著影响蛋白质的凝胶性和溶解性等功能特性,进而影响其在肉制品、植物蛋白饮料中的应用效果。目前常采用提取蛋白质后再用电泳及光密度法测定球蛋白、伴球蛋白及亚基含量的方法,操作步骤繁琐,样品... 花生球蛋白、伴花生球蛋白及亚基含量显著影响蛋白质的凝胶性和溶解性等功能特性,进而影响其在肉制品、植物蛋白饮料中的应用效果。目前常采用提取蛋白质后再用电泳及光密度法测定球蛋白、伴球蛋白及亚基含量的方法,操作步骤繁琐,样品损失量大。为此收集了178个花生品种,分别提取蛋白,采用电泳法测定球蛋白、伴球蛋白、23.5和37.5 kDa亚基含量并获得大量数据的基础上,利用近红外光谱技术进行整粒花生样品的光谱扫描,将其与传统方法测定的化学值进行拟合,采用偏最小二乘回归(PLSR)化学计量法构建数学模型。通过比较单一和复合光谱预处理方式,对比模型相关系数和误差评估预测模型性能。确定球蛋白模型最佳预处理方法为2^(nd)-der with Detrend,校正集相关系数为0.92,标准差为1.41;伴球蛋白模型最佳预处理方法为Detrend with 1^(st)-der,校正集相关系数为0.85,标准差为1.46;23.5 kDa亚基含量模型最佳预处理方法为Normalization with 2^(nd)-der,校正集相关系数为0.91,标准差为0.53;37.5 kDa模型最佳预处理方法为Detrend with Baseline,校正集相关系数为0.91,标准差为0.89。外部验证结果表明,球蛋白预测均方根误差(square errors of predi ction,SEP)为1.25,伴球蛋白SEP为0.73,23.5 kDa模型SEP为0.47,37.5 kDa模型SEP为0.75。本研究基于近红外光谱技术实现了对整粒花生进行球蛋白、伴球蛋白、23.5 kDa和37.5 kDa亚基含量的同步、快速和无损检测,为育种专家加工专用品种选育和蛋白加工企业原料选用提供了根据。 展开更多
关键词 近红外光谱分析 花生球蛋白 伴花生球蛋白 亚基含量(23.5和37.5 kda) 偏最小二乘法(PLSR)
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Mechanism of over-activation in direct pathway mediated by dopamine D_1 receptor in rats with levodopa-induced dyskinesias 被引量:9
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作者 Xue-Bing CAO Qiang GUAN Yan XU Lan WANG Sheng-Gang SUN 《Neuroscience Bulletin》 SCIE CAS CSCD 2006年第3期159-164,共6页
Objective To study the changes of prodynorphin (PDyn) gene expression and dopamine and cAMPregulated phosphoprotein of 32 kDa (DARPP-32) phosphorylation in rats with levodopa-induced dyskinesias (LID), and to ex... Objective To study the changes of prodynorphin (PDyn) gene expression and dopamine and cAMPregulated phosphoprotein of 32 kDa (DARPP-32) phosphorylation in rats with levodopa-induced dyskinesias (LID), and to explore the mechanism of over-activation in direct pathway mediated by dopamine D1 receptor. Methods Parkinson's disease (PD) rats were received levodopa (10 mg/kg, i.p.) for 28 d to get the LID rats. According to the behavior scale, LID rats were divided into mild (n=8) and severe (n=16) groups. On day 29, 8 rats in severe LID group were given an acute intraperitoneal injection of MK-801 (0.1 mg/kg) 15 min before levodopa treatment (MK-801 group, n=8). The normal rats received same course and dosage of levodopa as the control group (n=8). Hybridization in situ was used to measure the expression of PDyn mRNA in striatum. Protein and mRNA levels of total DARPP-32 and phospho-Thr-34 DARPP-32 level were measured by immunoblotting and RT-PCR, respectively. Results The levels of PDyn mRNA and phospho-Thr-34 DARPP-32 increased significantly in LID rats compared with control rats (P〈0.01), and they also increased markedly in severe LID group compared with mild group (P〈0.01). Conclusion Phospho-Thr-34 DARPP-32 level was increased in LID rats, which contributed to the over-activation of direct pathway mediated by dopamine D1 receptor. 展开更多
关键词 levodopa-induced dyskinesias PRODYNORPHIN Dopamine and cAMP-regulated phosphoprotein of 32 kda
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Nuclear domain 10 of the viral aspect 被引量:7
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作者 Yisel A Rivera-Molina Francisco Puerta Martínez Qiyi Tang 《World Journal of Virology》 2013年第3期110-122,共13页
Nuclear domain 10(ND10) are spherical bodies distributed throughout the nucleoplasm and measuring around 0.2-1.0 μm. First observed under an electron microscope, they were originally described as dense bodies found i... Nuclear domain 10(ND10) are spherical bodies distributed throughout the nucleoplasm and measuring around 0.2-1.0 μm. First observed under an electron microscope, they were originally described as dense bodies found in the nucleus. They are known by a number of other names, including Promyelocytic Leukemia bodies(PML bodies), Kremer bodies, and PML oncogenic domains. ND10 are frequently associated with Cajal bodies and cleavage bodies. It has been suggested that they play a role in regulating gene transcription. ND10 were originally characterized using human autoantisera, which recognizes Speckled Protein of 100 kD a, from patients with primary biliary cirrhosis. At the immunohistochemical level, ND10 appear as nuclear punctate structures, with 10 indicating the approximate number of dots per nucleus observed. ND10 do not colocalize with kinetochores, centromeres, sites of mR NA processing, or chromosomes. Resistance of ND10 antigens to nuclease digestion and salt extraction suggest that ND10 are associated with the nuclear matrix.They are often identified by immunofluorescent assay using specific antibodies against PML, Death domainassociated protein, nuclear dot protein(NDP55), and so on. The role of ND10 has long been the subject of investigation, with the specific connection of ND10 and viral infection having been a particular focus for almost 20 years. This review summarizes the relationship of ND10 and viral infection. Some future study directions are also discussed. 展开更多
关键词 Nuclear domain 10 PROMYELOCYTIC LEUKEMIA SPECKLED PROTEIN of 100 kda Death domainassociated PROTEIN Virus VIRAL replication
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Gabor特征均值的子空间人脸识别算法的改进 被引量:5
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作者 林克正 许颖 李姝 《哈尔滨理工大学学报》 CAS 2012年第5期65-68,共4页
针对人脸图像局部特征提取不充分的问题,在基于子空间分析的人脸识别算法中,提出了在线性和非线性空间中实现基于2DGabor均值的子空间人脸识别算法.首先,根据人脸图像的5个特殊区域,对人脸图像进行分块处理,分别对每一块进行2DGabor运算... 针对人脸图像局部特征提取不充分的问题,在基于子空间分析的人脸识别算法中,提出了在线性和非线性空间中实现基于2DGabor均值的子空间人脸识别算法.首先,根据人脸图像的5个特殊区域,对人脸图像进行分块处理,分别对每一块进行2DGabor运算,并把每个训练样本相应像素点得到的特征矢量取均值,得到图像的特征向量,然后在线性和非线性空间中利用2DPCA(two-dimensional principle component analysis)和KDA(kernel fisher discriminant analysis)对特征向量进行降维处理,最后利用最近邻分类器和支持向量机分类器SVM(support vector machine)进行特征分类与识别,通过对ORL和FERET标准人脸库图像进行的实验仿真即对比结果表明,基于2DGabor均值的方法不仅提高识别率,而且对于人脸光照、姿态和表情变换均具有良好的鲁棒性. 展开更多
关键词 人脸识别 子空间 2DGabor均值 2DPCA kda
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ZBD-2改善创伤后应激障碍模型小鼠恐惧焦虑和抑郁样行为的作用
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作者 李旭波 靳雨晨 +4 位作者 王欣赏 姜永莉 颜雨暄 宋大可 刘水冰 《空军军医大学学报》 CAS 2023年第12期1170-1176,共7页
目的探讨转位蛋白18 kDa(TSPO)配体ZBD-2对创伤后应激障碍(PTSD)模型小鼠行为的影响。方法48只雄性C57BL/6小鼠随机分为正常对照(Control)组、PTSD模型(Model)组、PTSD模型+ZBD-2(低、中、高剂量)组、PTSD模型+帕罗西汀阳性对照(Model+P... 目的探讨转位蛋白18 kDa(TSPO)配体ZBD-2对创伤后应激障碍(PTSD)模型小鼠行为的影响。方法48只雄性C57BL/6小鼠随机分为正常对照(Control)组、PTSD模型(Model)组、PTSD模型+ZBD-2(低、中、高剂量)组、PTSD模型+帕罗西汀阳性对照(Model+Paro)组,每组8只。采用条件性恐惧(CF)联合单一连续应激的双重应激建立小鼠PTSD模型,通过行为学旷场实验、高架十字迷宫实验、悬尾实验、恐惧记忆实验观察ZBD-2对PTSD模型小鼠恐惧记忆的影响及对焦虑和抑郁样行为的改善作用。结果与Control组相比,Model组小鼠在旷场中央区域运动的总路程和时间均显著缩短(P<0.01),进入高架十字迷宫开臂的次数和滞留时间均明显减少(P<0.01),悬尾不动时间延长(P<0.01),在CF中僵住时间显著延长(P<0.01),提示PTSD模型制备成功。与Model组小鼠相比,PTSD模型+ZBD-2组和Model+Paro组显著改善上述行为学表现(P<0.05,P<0.01),其中PTSD模型+ZBD-2组尤以中剂量效果最佳。结论TSPO配体ZBD-2可有效改善PTSD模型小鼠的恐惧、焦虑和抑郁样行为,可作为治疗PTSD潜在的侯选药物。 展开更多
关键词 转运蛋白18 kda ZBD-2 创伤后应激障碍 焦虑 抑郁
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NUP37的泛癌分析及其在胰腺癌中的功能和预后价值
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作者 吴海斌 匡鹏 +3 位作者 马丹丹 龚齐 董庆泰 傅涛 《联勤军事医学》 CAS 2023年第9期737-742,747,共7页
目的 对核通道蛋白37 kDa(nucleoporin 37 kDa, NUP37)进行泛癌分析,观察NUP37对胰腺癌(pancreatic adenocarcinoma, PAAD)细胞SW1990增殖、侵袭及迁移的影响。探讨NUP37在PAAD中的表达差异、临床意义及预后价值,并预测NUP37在PAAD中可... 目的 对核通道蛋白37 kDa(nucleoporin 37 kDa, NUP37)进行泛癌分析,观察NUP37对胰腺癌(pancreatic adenocarcinoma, PAAD)细胞SW1990增殖、侵袭及迁移的影响。探讨NUP37在PAAD中的表达差异、临床意义及预后价值,并预测NUP37在PAAD中可能的作用机制。方法 从癌症基因组图谱(The Cancer Genome Atlas, TCGA)数据库下载与整理NUP37在33种肿瘤及11 057例样本的mRNA表达水平及生存预后相关数据,统计分析NUP37在泛癌中的表达及预后情况。分别采用5-乙炔基-2′脱氧尿嘧啶核苷(5-ethynyl-2′-deoxyuridine, EdU)免疫荧光实验、Transwell实验、划痕实验检测过表达NUP37和沉默NUP37对SW1990细胞增殖、侵袭、迁移的影响。利用基因表达水平值的交互式分析平台(Gene Expression Profiling Interactive Analysis, GEPIA)数据库分析NUP37在PAAD中的表达及预后。从TCGA数据库获取PAAD患者NUP37表达水平、临床病理特征及生存时间等数据,统计分析NUP37表达水平与PAAD患者临床病理特征及预后的关系。通过基因组富集分析(Gene Set Enrichment Analysis, GSEA)预测NUP37在PAAD中可能调控的信号通路。结果 泛癌分析结果显示,NUP37在膀胱尿路上皮癌(bladder urothelial carcinoma, BUC)、乳腺浸润癌(breast invasive carcinoma, BRCA)、胆管癌(cholangiocarcinoma, CHOL)等17种肿瘤中高表达(P<0.05),且NUP37高表达预示着PAAD、肺腺癌(lung adenocarcinoma, LUAD)、肝细胞性肝癌(liver hepatocellular carcinoma, LIHC)等7种肿瘤患者的生存状态更差(P<0.05)。GEPIA数据库分析结果表明,NUP37在PAAD组织中的mRNA表达水平显著高于正常胰腺组织(P<0.05),且NUP37高表达组PAAD患者的总生存期显著低于低表达组患者(P<0.05),预后更差。EdU免疫荧光实验检测结果显示,过表达NUP37促进PAAD SW1990细胞增殖(P<0.01),沉默NUP37则抑制PAAD SW1990细胞增殖(P<0.01)。Transwell实验检测结果显示,过表达NUP37促进PAAD SW1990细胞侵袭(P<0.001),沉默NUP37则抑 展开更多
关键词 核通道蛋白37 kda 泛癌 胰腺癌 表达 细胞功能 预后
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虚拟偶像KDA女团——电竞文化与粉丝文化结合的典型范例 被引量:5
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作者 徐越 付煜鸿 《新媒体研究》 2019年第3期90-91,共2页
随着互联网的不断发展,电竞文化与粉丝文化作为青年亚文化的分支在不断发展壮大的同时,也逐渐打破其被边缘化的处境。在此背景下诞生的虚拟偶像团体KDA具有开创性地将电竞游戏角色转变为虚拟偶像,以女团歌手身份推出音乐作品,其背后所... 随着互联网的不断发展,电竞文化与粉丝文化作为青年亚文化的分支在不断发展壮大的同时,也逐渐打破其被边缘化的处境。在此背景下诞生的虚拟偶像团体KDA具有开创性地将电竞游戏角色转变为虚拟偶像,以女团歌手身份推出音乐作品,其背后所体现的电竞文化与粉丝文化的交融值得研究。由此,文章首先通过对虚拟偶像等概念的梳理明确KDA女团在不同文化领域下的角色定位,结合其出道以来的新闻、粉丝话语等分析其中所体现的电竞文化与粉丝文化的融合。最后,文章还尝试对电竞与粉丝文化融合提出相关可行性建议及发展路径。 展开更多
关键词 虚拟偶像 粉丝文化 电竞文化 kda 女团
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Amino Acid Composition and Functional Properties of Giant Red Sea Cucumber (Parastichopus californicus) Collagen Hydrolysates 被引量:5
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作者 LIU Zunying SU Yicheng ZENG Mingyong 《Journal of Ocean University of China》 SCIE CAS 2011年第1期80-84,共5页
Giant red sea cucumber (Parastichopus californicus) is an under-utilized species due to its high tendency to autolysis.The aim of this study was to evaluate the functional properties of collagen hydrolysates from this... Giant red sea cucumber (Parastichopus californicus) is an under-utilized species due to its high tendency to autolysis.The aim of this study was to evaluate the functional properties of collagen hydrolysates from this species.The degree of hydrolysis (DH),amino acid composition,SDS-PAGE,emulsion activity index (EAI),emulsion stability index (ESI),foam expansion (FE),and foam stability (FS) of hydrolysates were investigated.The effects of pH on the EAI,ESI FE and FS of hydrolysates were also inves-tigated.The results indicated that the β and α1 chains of the collagen were effectively hydrolyzed by trypsin at 50℃ with an En-zyme/Substrate (E/S) ration of 1:20 (w:w).The DH of collagen was up to 17.3% after 3 h hydrolysis with trypsin.The hydrolysates had a molecular weight distribution of 1.1 17 kDa,and were abundant in glycine (Gly),proline (Pro),glutamic acid (Glu),alanine (Ala) and hydroxyproline (Hyp) residues.The hydrolysates were fractionated into three fractions (< 3 kDa,3 10 kDa,and > 10 kDa),and the fraction of 3 10 kDa exhibited a higher EAI value than the fraction of > 10 kDa (P<0.05).The fraction of > 10 kDa had higher FE and FS values than other fractions (P<0.05).The pH had an important effect on the EAI,ESI,FE and FS.All the fractions showed undesirable emulsion and forming properties at pH 4.0.Under pH 7.0 and pH 10.0,the 3 10 kDa fraction showed higher EAI value and the fraction of > 10 kDa showed higher FE value,respectively.They are hoped to be utilized as functional ingredients in food and nutraceutical industries. 展开更多
关键词 giant red sea cucumber COLLAGEN HYDROLYSATES functional properties
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日本血吸虫热休克蛋白40 kDa免疫学功能研究 被引量:3
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作者 余艳雄 李莎莎 +5 位作者 朱继峰 陈晓军 徐志鹏 李娅琳 周莎 苏川 《中国血吸虫病防治杂志》 CAS CSCD 北大核心 2020年第3期262-267,272,共7页
目的探索日本血吸虫热休克蛋白40 k Da(Sj HSP40)免疫学功能。方法采用生物信息学方法分析Sj HSP40蛋白序列同源性,并预测其B细胞及T细胞表位。应用PCR技术扩增全长Sj HSP40基因,将其克隆入原核表达质粒p GEX-6P-1,再转入大肠埃希菌BL21... 目的探索日本血吸虫热休克蛋白40 k Da(Sj HSP40)免疫学功能。方法采用生物信息学方法分析Sj HSP40蛋白序列同源性,并预测其B细胞及T细胞表位。应用PCR技术扩增全长Sj HSP40基因,将其克隆入原核表达质粒p GEX-6P-1,再转入大肠埃希菌BL21中;以异丙基-β-D-硫代半乳糖苷(IPTG)诱导表达,再经亲和柱分离纯化获得谷胱甘肽巯基转移酶(GST)-Sj HSP40融合蛋白,分别采用十二烷基磺酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)及Western blotting进行鉴定。以GST-Sj HSP40免疫BALB/c小鼠后,以酶联免疫吸附试验(ELISA)检测小鼠血清中抗Sj HSP40特异性Ig G抗体及其亚型Ig G1、Ig G2a抗体,采用流式检测术观察Sj HSP40对CD4+T细胞亚群分化的影响。结果 Sj HSP40含有7个潜在B细胞表位及多个T细胞表位(CTL表位和Th表位)。成功构建了原核表达重组质粒p GEX-6P-1-Sj HSP40,并通过诱导表达和蛋白纯化获得GST-Sj HSP40融合蛋白。与其他组相比,GST-Sj HSP40免疫小鼠血清中抗Sj HSP40特异性Ig G抗体及其亚型Ig G1和Ig G2a水平均显著升高,但Sj HSP40对CD4+T淋巴细胞分化无显著影响。结论 Sj HSP40可诱导小鼠产生特异性体液免疫应答,但不影响小鼠体内各类Th免疫反应平衡,可作为潜在疫苗候选分子。 展开更多
关键词 日本血吸虫 热休克蛋白40 kda 免疫学功能 体液免疫
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血浆重组人MAp44蛋白水平对心搏骤停后综合征患者预后的预测价值
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作者 王媛媛 穆春玲 +1 位作者 宋宸晏 谢桂芳 《医学综述》 CAS 2023年第24期5835-5840,共6页
目的探究血浆重组人甘露聚糖结合凝集素相关蛋白44 kDa(MAp44)水平对心搏骤停后综合征患者预后的预测价值。方法选取2020年1月至2023年1月张家口市第一医院收治的116例心搏骤停后综合征患者作为研究组,另选取同期体检的116名健康志愿者... 目的探究血浆重组人甘露聚糖结合凝集素相关蛋白44 kDa(MAp44)水平对心搏骤停后综合征患者预后的预测价值。方法选取2020年1月至2023年1月张家口市第一医院收治的116例心搏骤停后综合征患者作为研究组,另选取同期体检的116名健康志愿者作为对照组。检测所有受试者血浆重组人MAp44水平,并比较对照组与研究组重组人血浆MAp44水平。收集研究组临床资料,并根据患者住院期间是否发生死亡分为生存组和死亡组,比较两组患者血浆重组人MAp44水平及临床资料,采用Logistic回归分析影响心搏骤停后综合征患者发生死亡的危险因素。绘制受试者工作特征(ROC)曲线分析血浆重组人MAp44水平对心搏骤停后综合征患者发生死亡的预测价值。结果116例患者中,71例患者在住院期间死亡,死亡率为61.21%(71/116)。研究组血浆重组人MAp44水平高于对照组[(1539±108)μg/L比(1001±137)μg/L](t=32.907,P<0.001)。死亡组血浆重组人MAp44、心肌肌钙蛋白T、尿素氮、肌酸激酶同工酶(CK-MB)、血肌酐水平高于生存组[(1734±114)μg/L比(1231±103)μg/L、(0.73±0.12)μg/L比(0.41±0.06)μg/L、(20.2±3.2)μmol/L比(10.4±2.0)μmol/L、(64±7)U/L比(36±4)U/L、(186±17)μmol/L比(137±14)μmol/L](P<0.01),纤维蛋白原水平低于生存组[(2.42±0.39)g/L比(3.82±0.54)g/L](P<0.01)。多因素Logistic回归分析结果显示,血浆重组人MAp44、心肌肌钙蛋白T、尿素氮、CK-MB、血肌酐水平升高是影响心搏骤停后综合征患者发生死亡的危险因素(OR=5.743,95%CI 3.244~8.242;OR=3.582,95%CI 1.218~5.947;OR=3.900,95%CI 1.557~6.243;OR=4.845,95%CI 2.285~7.406;OR=3.307,95%CI 1.361~5.253)(P<0.01),纤维蛋白原水平升高是保护因素(P<0.01)。ROC曲线显示,血浆重组人MAp44水平预测心搏骤停后综合征患者发生死亡的ROC曲线下面积、最佳截断值、灵敏度、特异度、约登指数分别为0.803、1356.54 ng/L、86.30%、79.50%、65.80%。结论心搏骤� 展开更多
关键词 心搏骤停后综合征 甘露聚糖结合凝集素相关蛋白44 kda 血浆 预后
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p85S6K sustains synaptic GluA1 to ameliorate cognitive deficits in Alzheimer’s disease
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作者 Jia-Bing Li Xiao-Yu Hu +10 位作者 Mu-Wen Chen Cai-Hong Xiong Na Zhao Yan-Hui Ge Hao Wang Xiao-Ling Gao Nan-Jie Xu Lan-Xue Zhao Zhi-Hua Yu Hong-Zhuan Chen Yu Qiu 《Translational Neurodegeneration》 CSCD 2023年第1期890-907,共18页
Background Ribosomal protein S6 kinase 1(S6K1)is a serine-threonine kinase that has two main isoforms:p70S6K(70-kDa isoform)and p85S6K(85-kDa isoform).p70S6K,with its upstream mammalian target of rapamycin(mTOR),has b... Background Ribosomal protein S6 kinase 1(S6K1)is a serine-threonine kinase that has two main isoforms:p70S6K(70-kDa isoform)and p85S6K(85-kDa isoform).p70S6K,with its upstream mammalian target of rapamycin(mTOR),has been shown to be involved in learning and memory and participate in the pathophysiology of Alzheimer’s dis-ease(AD).However,the function of p85S6K has long been neglected due to its high similarity to p70S6k.The role of p85S6K in learning and memory is still largely unknown.Methods We fractionated the postsynaptic densities to illustrate the differential distribution of p85S6K and p70S6K.Coimmunoprecipitation was performed to unveil interactions between p85S6K and the GluA1 subunit of AMPA receptor.The roles of p85S6K in synaptic targeting of GluA1 and learning and memory were evaluated by specific knockdown or overexpression of p85S6K followed by a broad range of methodologies including immunofluorescence,Western blot,in situ proximity ligation assay,morphological staining and behavioral examination.Further,the expression level of p85S6K was measured in brains from AD patients and AD model mice.Results p85S6K,but not p70S6K,was enriched in the postsynaptic densities.Moreover,knockdown of p85S6K resulted in defective spatial and recognition memory.In addition,p85S6K could interact with the GluA1 subunit of AMPA receptor through synapse-associated protein 97 and A-kinase anchoring protein 79/150.Mechanistic studies demonstrated that p85S6K could directly phosphorylate GluA1 at Ser845 and increase the amount of GluA1 in syn-apses,thus sustaining synaptic function and spine densities.Moreover,p85S6K was found to be specifically decreased in the synaptosomal compartment in the brains of AD patients and AD mice.Overexpression of p85S6K ameliorated the synaptic deficits and cognitive impairment in transgenic AD model mice.Conclusions These results strongly imply a significant role for p85S6K in maintaining synaptic and cognitive function by interacting with GluA1.The findings provide an insight into the r 展开更多
关键词 Alzheimer’s disease COGNITION GluA1 subunit of AMPA receptors Ribosomal S6 protein kinase 1 85 kda isoform
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酵母甘露聚糖(20 kDa)的生物安全性及体内分布研究 被引量:2
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作者 付乾振 王佳奇 +3 位作者 樊坤 刘洁 王子朝 张慧茹 《河南工业大学学报(自然科学版)》 CAS 北大核心 2021年第3期58-63,共6页
酵母甘露聚糖具有多种生物活性,对其生物安全性、体内分布的研究可为体内应用提供基础数据。通过MTT法和体外溶血实验,研究了酵母甘露聚糖(20 k Da)对Caco-2细胞的毒性和红细胞的溶血性,通过对KM实验小鼠灌服100 mg/kg的酵母甘露聚糖溶... 酵母甘露聚糖具有多种生物活性,对其生物安全性、体内分布的研究可为体内应用提供基础数据。通过MTT法和体外溶血实验,研究了酵母甘露聚糖(20 k Da)对Caco-2细胞的毒性和红细胞的溶血性,通过对KM实验小鼠灌服100 mg/kg的酵母甘露聚糖溶液,检测酵母甘露聚糖随时间在动物肠道(十二指肠、空肠、回肠)、血液及脏器(心、肝、脾、肺和肾)的分布情况。结果表明:160μg/m L的酵母甘露聚糖对Caco-2细胞无明显毒性,反而有轻微的促增殖作用(115.6%);在80~200μg/m L范围内,酵母甘露聚糖对红细胞的溶血性低于5%,在生物安全范围内;小鼠灌服酵母甘露聚糖后,30~90 min能明显提高血糖水平;1~3 h糖主要分布在肝脏和肺脏中,心脏和肾脏中糖含量变化不大,脾脏糖含量缓慢下降;肠道中未吸收的酵母甘露聚糖,随着时间(0~90 min)推移,在十二指肠中留存时间较短,空肠的糖含量在30 min较高,约60 min时,糖流动到达回肠,酵母甘露聚糖主要在空肠和回肠被吸收。酵母甘露聚糖(20 kDa)有高的生物相容性,无细胞毒性、溶血性,能在小肠中被机体吸收入血,主要分布于肝脏和肺脏中。 展开更多
关键词 酵母甘露聚糖(20 kda) 生物安全性 体内分布 细胞毒性 溶血性
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氯胺酮对幼年小鼠空间学习记忆功能及海马脑区TSPO蛋白的影响 被引量:2
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作者 李桂婷 张蕊 +1 位作者 邹珊珊 丁明 《山东大学学报(医学版)》 CAS 北大核心 2015年第4期55-60,共6页
目的:观察幼年小鼠连续多次接受氯胺酮麻醉后学习记忆认知功能及海马脑区内 TSPO 蛋白的表达情况。方法出生21 d 的幼年小鼠24只随机分为对照组(n =12)和氯胺酮组(n =12),每天1次分别经腹腔注射生理盐水和氯胺酮,连续7 d。然... 目的:观察幼年小鼠连续多次接受氯胺酮麻醉后学习记忆认知功能及海马脑区内 TSPO 蛋白的表达情况。方法出生21 d 的幼年小鼠24只随机分为对照组(n =12)和氯胺酮组(n =12),每天1次分别经腹腔注射生理盐水和氯胺酮,连续7 d。然后进行 Morris 水迷宫实验,包括4 d 的适应性训练和1 d 的空间探索实验,观察小鼠的学习记忆功能的改变。水迷宫行为学测试后处死小鼠,取双侧的海马脑区,采用 Western blotting 技术和免疫荧光双标技术检测小鼠海马内小胶质细胞的变化和 TSPO 表达水平。结果训练期3~4 d,氯胺酮组小鼠潜伏期明显长于对照组(P <0.05)。探索实验显示,与对照组比较,氯胺酮组小鼠在平台所在象限滞留时间和经过次数明显减少(P <0.05);Western blotting 分析结果表明,氯胺酮组幼年小鼠海马小胶质细胞标记物 Iba-1和 TSPO 蛋白表达明显增多;免疫荧光双重标记技术显示,氯胺酮组小鼠海马小胶质细胞发生了形态学的改变,TSPO 蛋白的表达增强。结论氯胺酮组小鼠海马脑区内小胶质细胞被激活,与之共同表达的 TSPO 蛋白的表达增高,学习记忆等认知功能减退。 展开更多
关键词 氯胺酮 学习记忆能力 小胶质细胞 18 kda 转位蛋白
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Isolation and Characterization of Fucoidans from Five Brown Algae and Evaluation of Their Antioxidant Activity 被引量:3
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作者 QU Guiyan LIU Xu +2 位作者 WANG Dongfeng YUAN Yi HAN Lijun 《Journal of Ocean University of China》 SCIE CAS 2014年第5期851-856,共6页
In this study, we evaluated the chemical property and antioxidant activity of fucoidans isolated from brown algae, Laminaria japonica(LJF), Lessonia nigrescens(LNF), Lessonia trabeculata(LTF), Ascophyllum mackaii(AMF)... In this study, we evaluated the chemical property and antioxidant activity of fucoidans isolated from brown algae, Laminaria japonica(LJF), Lessonia nigrescens(LNF), Lessonia trabeculata(LTF), Ascophyllum mackaii(AMF), and Ecklonia maxima(EMF). LJF was less in sulfate content(14.16%) and more in galactose and mannose content(1.08 and 0.68) than the documented early. EMF contained 20%–30% of sulfate and fucose, 0.97 in molar ratio which was lower than that of sulfate to other four fucoidans(1.21–1.41). AMF(162 kDa) and EMF(150 kDa) were the first two largest in molecular weight, which were followed by LJP(126 kDa), LNF(113 kDa) and LTF(105 kDa). The fucoidans isolated these algae showed a wide range of antioxidant activity in vitro. It was found that the reducing power of the isolated fucoidans was positively correlated with their sulfate content and molecular weight. In addition, LNF and LTF at low concentrations exhibited high superoxide and hydroxyl radical scavenging activity. This demonstrated that low molecular weight fucoidans may perform a high antioxidant activity. 展开更多
关键词 fucoidans composition antioxidant property Laminaria japonica Lessonia nigrescens Lessonia trabeculata Ascophyllum mackaii Ecklonia maxima
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ROS-mediated BNIP3-dependent mitophagy promotes coelomocyte survival in Apostichopus japonicus in response to Vibrio splendidus infection 被引量:2
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作者 Lian-Lian Sun Yi-Na Shao +1 位作者 Mei-Xiang You Cheng-Hua Li 《Zoological Research》 SCIE CAS CSCD 2022年第2期285-300,共16页
Organisms produce high levels of reactive oxygen species(ROS)to kill pathogens or act as signaling molecules to induce immune responses;however,excessive ROS can result in cell death.To maintain ROS balance and cell s... Organisms produce high levels of reactive oxygen species(ROS)to kill pathogens or act as signaling molecules to induce immune responses;however,excessive ROS can result in cell death.To maintain ROS balance and cell survival,mitophagy selectively eliminates damaged mitochondria via mitophagy receptors in vertebrates.In marine invertebrates,however,mitophagy and its functions remain largely unknown.In the current study,Vibrio splendidus infection damaged mitochondrial morphology in coelomocytes and reduced mitochondrial membrane potential(ΔΨm)and mitophagosome formation.The colocalization of mitochondria and lysosomes further confirmed that lipopolysaccharide(LPS)treatment increased mitophagy flux.To explore the regulatory mechanism of mitophagy,we cloned Bcl2/adenovirus E1 B 19 kDa protein-interacting protein 3(BNIP3),a common mitophagy receptor,from sea cucumber Apostichopus japonicus(Aj BNIP3)and confirmed that Aj BNIP3 was significantly induced and accumulated in mitochondria after V.splendidus infection and LPS exposure.At the mitochondrial membrane,Aj BNIP3 interacts with microtubule-associated protein 1 light chain 3(LC3)on phagophore membranes to mediate mitophagy.After Aj BNIP3 interference,mitophagy flux decreased significantly.Furthermore,Aj BNIP3-mediated mitophagy was activated by ROS following the addition of exogenous hydrogen peroxide(H2 O2),ROS scavengers,and ROS inhibitors.Finally,inhibition of BNIP3-mediated mitophagy by Aj BNIP3 small interfering RNA(si RNA)or high concentrations of lactate increased apoptosis and decreased coelomocyte survival.These findings highlight the essential role of Aj BNIP3 in damaged mitochondrial degradation during mitophagy.This mitophagy activity is required for coelomocyte survival in A.japonicus against V.splendidus infection. 展开更多
关键词 Apostichopus japonicus MITOPHAGY Bcl2/adenovirus E1B 19 kda protein-interacting protein 3 Reactive oxygen species Microtubule-associated protein 1 light chain 3
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日本血吸虫热休克蛋白60 kDa的免疫原性及保护性研究 被引量:1
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作者 金鑫 陈晓军 +4 位作者 朱继峰 徐志鹏 刘丰 周莎 苏川 《中国血吸虫病防治杂志》 CAS CSCD 北大核心 2016年第1期45-50,共6页
目的研究日本血吸虫热休克蛋白60 kDa(SjHSP60)免疫原性,评价其免疫保护性及可能机制。方法通过在线生物信息学软件预测SjHSP60的B细胞表位,随后用SjHSP60免疫BALB/c小鼠后检测特异性抗体水平和淋巴细胞增殖以评估其免疫原性,进一步通... 目的研究日本血吸虫热休克蛋白60 kDa(SjHSP60)免疫原性,评价其免疫保护性及可能机制。方法通过在线生物信息学软件预测SjHSP60的B细胞表位,随后用SjHSP60免疫BALB/c小鼠后检测特异性抗体水平和淋巴细胞增殖以评估其免疫原性,进一步通过攻击感染实验观察其免疫保护效果;最后分选免疫小鼠的CD4^+CD25^+调节性T细胞(Treg)与CD4^+CD25^-T细胞共培养,通过细胞增殖实验检测CD4^+CD25^+Treg细胞的抑制功能。结果生物信息学预测结果显示,SjHSP60中存在多个B细胞表位的优势区段。SjHSP60可在小鼠体内诱导特异性抗体(P<0.01),也可诱导小鼠脾细胞发生增殖(P<0.01)和分泌IFN-γ(P<0.01);但攻击感染实验显示,SjHSP60免疫小鼠体内虫荷(P>0.05)、卵荷(P>0.05)均未显著减少。体外共培养实验表明,SjHSP60可显著增强小鼠CD4^+CD25^+Treg细胞的免疫抑制功能(P<0.01)。结论SjHSP60对宿主免疫系统可发挥"双刃剑"作用,即在诱导特异性抗感染免疫应答的同时又可增强免疫抑制功能,从而削弱了其免疫保护作用。 展开更多
关键词 日本血吸虫 热休克蛋白60 kda 免疫保护性 CD4^+CD25^+调节性T细胞
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Creation of Male Sterile Line in Tobacco With HSP70 Anti-sense Fragment 被引量:1
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作者 易凌霄 李祥 +1 位作者 陈建南 夏石头 《Agricultural Science & Technology》 CAS 2016年第10期2262-2266,2296,共6页
In order to create the Male Sterile Line in tobacco, the anti-sense fragment of HSP70 gene was linked to anther specific expression promoter TA29 and the reconstructed vector was transformed into tobacco by Agrobacter... In order to create the Male Sterile Line in tobacco, the anti-sense fragment of HSP70 gene was linked to anther specific expression promoter TA29 and the reconstructed vector was transformed into tobacco by Agrobacterium mediated transformation, and the transformants were then screened. Gus and spot blotting hybridization analysis of the transformants indicated that anti-sense fragment of HSF70 gene had been integrated into tobacco genome and expressed, thus the male sterile tobacco line was obtained. Microscope observation of anther and pollen showed that pistils of transgenic tobacco were normal, whereas anthers and pollens were fairly abortive in the same transgenic tobacco flower, comparing with pistils and stamens in control plants. The ratio of HSI:'70 protein before and after heat shock in mitochondrial was found to be 1.39 in control tobacco plants and 1.01 in transgenic tobacco sterile lines. This is suggested that the anti-sense gene fragment of HSP70 can effectively inhibit the expression of HSP70 protein and lead to transgenic male sterility in tobacco flowers. The assay provided a new genetic engineering method for male sterility creation in plants. 展开更多
关键词 70 kda heat-shock protein Antisense gene Male sterility Gene engineering
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Condition Identification Based on Vibration Measurements for Free Spanning Submarine Pipelines 被引量:1
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作者 胡家顺 冯新 +1 位作者 李昕 周晶 《China Ocean Engineering》 SCIE EI 2008年第4期561-574,共14页
Free spanning pipelines are suspended between two points on an uneven seaffoor. The variations of structural conditions, such as the changes in soil property, flow velocity, axial force and span length etc., directly ... Free spanning pipelines are suspended between two points on an uneven seaffoor. The variations of structural conditions, such as the changes in soil property, flow velocity, axial force and span length etc., directly affect working performance of the whole submarine pipeline system. But until now few researches have focused on condition identification for free span (CIFS). A method to identify the operational conditions of free spanning submarine pipelines based on vibration measurements is proposed in this paper. Firstly, the ill-posedness of CIFS is analyzed in detail. Secondly, the framework for CIFS based on the nonlinear kernel discriminant analysis (KDA) is established. Thirdly, the internal structural characteristics of natural frequencies, normalized frequencies and frequency change ratios are studied. And then the condition feature vector for CIFS is extracted by use of the vibration measurements. Finally, the validity of the proposed approach is evaluated by a case study. The results demonstrate that the proposed approach can effectively identify each condition of free span when condition variation occurs even if under measurement noise. It is concluded that the proposed method is a promising tool for CIFS in real applications. 展开更多
关键词 submasine pipelines condition identfication free span kernel discriminant analysis( kda frequently structure
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