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Labeling polypeptide with ^(99m)Tc and bioactivity get back

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Nuclear Science and Techniques 2001年第2期12卷 99-104页

作者： LI shao-Lin JIANG Xiao-Fei PANG hua liu Fang-Xin SHI Qiong Department of Nuclear Medicine Chongqing University of Medical SciencesChongqing 400016

A method for labeling polypeptide (insulin) with technetium- 99(99mTc) was established without marked loss of biological activity. Following reduction of intrinsic disulfide bonds by mercaptoethanol and purification on a Sephadex G50 column, the polypeptide was labeled with 99mTc by transchelation from methylene diphosphonate (MDP). 99mTc labeled insulin was identified by thin layer chromatograph (TLC) and the change of blood sugar of mice injected, their hypoglycemic shock symptom was also observed. Six hours after labeling, the dissociation of labeled insulin was only 3%, Mom then on to 24 h, there was no more dissociation. The blood sugar concentration of mice injected with the mercaptoethanol-reduced insulin was (5.0±3.2)μmol.L-1, while those injected with the original insulin was (1.4±1.2)μmol.L-1, the difference was significant (Q test, p <0.01). Blood sugar concentration of the mice was 0.3±0.2μmol.L-1 for the labeled insulin, and was about the same with that for the original insulin. The labeling efficiency was 74.31% for the labeled insulin, whereas the original insulin cannot be labeled with 99mTc. The result suggests that while disulfide bonds of polypeptide were reduced by mercaptoethanol, it became free sulfhydryl group, and its bioactivity descended. Then free sulfhydryl group was chelated with 99mTc under mild condition, restablishing the disulfide bond, therefore, the bioactivity came back. The 99mTc-labeled insulin was stable during 24h.

关键词：肽生物试样 Tc标记胰岛素

Enhanced Photocatalytic Activity of Nanoparticle-Aggregated Ag–AgX(X=Cl, Br)@TiO_2 Microspheres Under Visible Light

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Nano-Micro Letters 2017年第4期9卷 139-151页

作者： Cuiling Zhang Hao hua Jianlin liu Xiangyu Han Qipeng liu Zidong Wei Chengbin shao Chenguo Hu Chongqing Engineering Laboratory for Detection Controland Integrated System Chongqing Technology and Business University College of Chemistry and Chemical Engineering College of Physics Chongqing University

Ag–AgX(X = Cl, Br)@TiO_2 nanoparticle-aggregated spheres with different mass ratio of R = TiO2/Ag(X) from 35:1 to 5:1 were synthesized by a facile sol–gel technique with post-photoreduction. The photocatalytic activities of both Ag–Ag Cl@TiO_2 and Ag–Ag Br@TiO_2 under visible light are effectively improved by ~3 times relative to TiO_2 NPAS under the simulated sunlight for the decomposition of methyl orange(MO). Ag–AgBr@TiO_2 showed 30% improvement and less stable in photocatalytic activity than that of AgCl@TiO_2. The role of Ag and Ag X nanoparticles on the surface of Ag–Ag X(X = Cl,Br)@TiO_2 was discussed. Ag on these samples not onlycan efficiently harvest visible light especially for Ag Cl, but also efficiently separate excited electrons and holes via the fast electron transfer from Ag X(X = Cl, Br) to metal Ag nanoparticles and then to TiO_2-aggregated spheres on the surface of heterostructure. On the basis of their efficient and stable photocatalytic activities under visible-light irradiation, these photocatalysts could be widely used for degradation of organic pollutants in aqueous solution.

关键词： Ag–AgX(X=Cl,Br)@TiO2 Nanoparticleaggregated spheres Methyl orange Visible light Photocatalysis

Environmentally Friendly Sizing Strategy for PBO Fiber-reinforced Composites through Building Carbon Nanosphere Coatings

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Chinese Journal of Polymer Science 2023年第2期41卷 306-314页

作者： Rong Ling shao-hua Wu Chun-Cheng Li Yao-Nan Xiao Jia-Jian liu Bo Zhang Beijing National Laboratory for Molecular Sciences Key Laboratory of Engineering PlasticsInstitute of ChemistryChinese Academy of Sciences(ICCAS)Beijing100190China University of the Chinese Academy of Sciences Beijing100049China

Sizing treatment has shown great potential in improving the interfacial properties of poly(p-phenylene benzodioxazole)(PBO)fiber-reinforced composites,but is severely limited due to the use of flammable and explosive organic ***,a new high-efficiency waterborne sizing agent has been developed by using functionalized carbon nanospheres(CNSs)as a *** to abundant oxygen-containing groups,the CNSs greatly improves the surface activity,wettability,and roughness of the PBO *** a result,the interfacial shear strength of the CNSs sized fiber-reinforced composite increases by 79.6%compared with that of the pristine fiber-reinforced ***,the excellent mechanical and thermal properties of the PBO fibers remain almost unchanged after sizing ***,this work provides an environmentally friendly and scalable method for constructing a strong interface between the PBO fibers and the matrix resins,which makes sense in promoting the application of PBO fiber-reinforced composites in aerospace and military industries.

关键词： Carbon nanospheres Sizing treatment PBO fiber-reinforced composites Environmentally friendly Scalable methods

Association of neonatal blood levels of brain-derived neurotrophic factor with development of autism spectrum disorder:a systematic review and meta-analysis

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World Journal of Pediatrics 2021年第2期17卷 164-170页

作者： Ya-Kun liu hua Gao shao-Bin Jin Wen-Jun Tu Ya-Jun Chen Department of General Surgery Beijing Children’s HospitalCapital Medical UniversityNo.56 Nanlishi St.Beijing 100045China Department of Pediatric Surgery Qilu Hospital of Shandong UniversityNo.107 West Wenhua StJinan 250000China Institute of Radiation Medicine Chinese Academy of Medical SciencePeking Union Medical CollegeNo.238 Baidi StTianjin 300192China Key Lab of Cerebral Microcirculation in Universities of Shandong Shandong First Medical UniversityShandong Academy of Medical SciencesNo.619 Changcheng St.Taian 271000China

Background Our goal was to evaluate the association between neonatal blood brain-derived neurotrophic factor(BDNF)level and autism spectrum disorder(ASD)diagnosis later in *** MEDLINE and Web of Science databases were searched from inception until September 16,*** lists of all relevant articles also were *** blood BDNF concentrations,standard deviations,sample sizes,and other data needed for calculation of effect sizes were extracted by two independent *** quality of the included studies was appraised using the Newcastle-Ottawa Scale for case-control *** were pooled using the random-effects *** Five case-control studies involving 1341 cases and 3395 controls were included in the *** meta-analysis of all included studies showed no significant difference in blood BDNF levels between neonates diagnosed with ASD later in life and healthy controls[standardized mean difference(SMD)=0.261;95%confidence interval(CI)-0.052 to 0.573;P=0.102],with high level of heterogeneity(Q=64.346;I2=93.784;P<0.001).A subgroup analysis by assay type showed decreased blood BDNF levels in ASDs compared to controls(SMD=—0.070;95%CI-0.114 to-0.026;P=0.002),with high level of homogeneity(Q=0.894;I2=0.000;P=0.827).No evidence of publication bias was *** Neonates diagnosed with ASD later in life have decreased blood levels of BDNF measured by double-antibody *** studies are warranted to facilitate a more robust conclusion.

关键词： Autism spectrum disorder Autistic disorder Brain-derived neurotrophic factor Neonates Neurotrophins

Atroposelective Synthesis of 2-Arylindoles via Chiral Phosphoric Acid-Catalyzed Direct Amination of Indoles

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Chinese Journal of Chemistry 2024年第7期42卷 731-735页

作者： Wen Bao Ye-Hui Chen Yu-Wei liu shao-hua Xiang Bin Tan School of Pharmacy&StateKey Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhouGansu 730000China Shenzhen Grubbs Institute Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong 518055China

Indole-based atropisomers are a very important class of axially chiral ***,the atroposelective synthesis of axially chiral 2-arylindole remains largely *** this study,we report the successful synthesis of atropisomeric 2-arylindoles using direct amination of indoles with p-quinonediimines in the presence of chiral phosphoric acid as a *** acts as an aminating reagent through formal polarity inversion of *** malonate group on the 2-aryl of 2-indoles was found to be essen-tial for high enantioselectivity of the *** could be due to the additional interaction between the ester group and the cata-lyst,as well as the intramolecular hydrogen *** findings provide a new strategy for the asymmetric construction of 2-arylindole atropisomers.

关键词： Chiral phosphoric acid Quinonediimines Direct amination Nucleophilic addition Asymmetric catalysis Enantioselectivity Axially chiral 2-arylindole Atroposelective synthesis

安氏Ⅱ类错[牙合]畸形佩戴Twin-block矫治器时上颌骨的应力分布

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中国组织工程研究 2025年第5期29卷 881-887页

作者：李帅刘桦商永慧刘义琮赵启航刘文大连医科大学辽宁省大连市116000 康复大学青岛医院/青岛市市立医院口腔医学中心山东省青岛市266000 青岛市崂山区青岛恩典嘉美口腔门诊部山东省青岛市266100

背景:Twin-block矫治器常用于安氏Ⅱ类错[牙合]畸形的矫治,其刺激下颌骨生长的作用机制已得到许多研究证实,但对上颌骨生长的影响尚不清楚。目的:通过有限元法分析安氏Ⅱ类错[牙合]畸形患者佩戴Twin-block矫治器时上颌骨复合体、周围骨... 详细信息

背景:Twin-block矫治器常用于安氏Ⅱ类错[牙合]畸形的矫治,其刺激下颌骨生长的作用机制已得到许多研究证实,但对上颌骨生长的影响尚不清楚。目的:通过有限元法分析安氏Ⅱ类错[牙合]畸形患者佩戴Twin-block矫治器时上颌骨复合体、周围骨缝及上颌牙列的应力分布。方法:选择在山东省康复大学青岛医院/青岛市市立医院口腔正畸科进行正畸治疗的安氏Ⅱ类错[牙合]畸形患者1例,测量患者佩戴Twin-block矫治器时的咬合力数据,采集其锥形束CT数据,建立包含上颌骨复合体、周边各骨缝、Twin-block矫治器及上颌牙列在内的有限元模型,通过ABAQUS软件模拟患者戴入Twin-block时上颌骨、骨缝及上颌牙列的应力分布与位移。结果与结论:①上颌前牙受到的等效应力明显小于后牙,两侧牙齿的最大等效应力分别为4.7975 MPa和8.7161 MPa,均位于第一前磨牙处;最大位移呈现在两侧上颌切牙处,分别为0.0805 mm和0.0810 mm;②骨缝的最大等效应力为1.284 MPa,主要集中在两侧翼腭缝及额颌缝,其余骨缝受力情况几乎无差异;骨缝的最大位移为0.07 mm,其中翼腭缝的位移量最大,其次是额颌缝;③上颌骨复合体受到的最大等效应力为27.18 MPa,主要集中在上颌骨前面梨状孔两侧、鼻额缝周边及颚骨后部翼腭缝附近;上颌骨的最大位移值为0.07 mm,主要集中于上颌牙槽骨;④结果显示,咬合力通过Twin-block矫治器作用于上颌骨复合体,导致上颌骨顺时针旋转、牙合平面变陡,应采取相应措施补偿这种趋势,例如建牙合过程中考虑上颌磨牙伸长、下颌磨牙压低,不仅能够将牙合平面整平,同时有利于下颌前伸,这将进一步提高Ⅱ类错[牙合]正畸治疗效果。

关键词：错牙合畸形组织构建骨组织工程 Twin-block矫治器功能矫治有限元分析

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面向大规模图像检索的哈希学习综述

软件学报 2025年第1期36卷 79-106页

作者：张雪凝刘兴波宋井宽聂秀山王少华尹义龙山东大学软件学院山东建筑大学计算机科学与技术学院电子科技大学计算机科学与工程学院

随着互联网空间中图像数据的爆发式增长和图像应用领域的拓宽,大规模图像检索的需求与日俱增.哈希学习为大规模图像检索提供显著的存储与检索效率,并成为近年来一个研究热点.现有哈希学习综述存在着时效性弱与技术路线不清晰的问题,即... 详细信息

随着互联网空间中图像数据的爆发式增长和图像应用领域的拓宽,大规模图像检索的需求与日俱增.哈希学习为大规模图像检索提供显著的存储与检索效率,并成为近年来一个研究热点.现有哈希学习综述存在着时效性弱与技术路线不清晰的问题,即多总结5–10年前的研究成果,且较少总结哈希学习算法各组成部分间的关联关系.鉴于此,通过总结近20年公开发表的哈希学习文献,对面向大规模图像检索的哈希学习进行系统的综述性研究.首先,介绍哈希学习的技术路线和哈希学习算法的主要组成部分,包括损失函数、优化策略及样本外扩展映射.其次,将面向图像检索的哈希学习算法分为无监督哈希方法和监督哈希方法两类,并分别梳理每类方法的研究现状和演化过程.然后,介绍哈希学习算法评估通用的图像数据集与评估指标,并通过对比实验分析部分经典算法的性能.最后,结合哈希学习的局限性与新挑战对其发展前景进行阶段性总结与展望.

关键词：图像检索大规模数据近似最近邻检索哈希学习相似性保持

残余胆固醇与进展为主要不良心血管事件的非罪犯病变易损斑块的相关性研究

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中国全科医学 2025年第3期28卷 299-304页

作者：杨红刘成刘森邵琪琪夭元昊付真彦新疆医科大学第一附属医院心脏中心新疆维吾尔自治区乌鲁木齐市830054

背景残余胆固醇(RC)被认为是动脉粥样硬化性心血管疾病的重要危险因素,而冠状动脉非罪犯病变(NCCLs)进展也是影响冠心病患者预后的重要因素,但是残余胆固醇与进展为主要不良心血管事件(MACE)的NCCLs易损斑块的关系尚不明确。目的探讨R... 详细信息

背景残余胆固醇(RC)被认为是动脉粥样硬化性心血管疾病的重要危险因素,而冠状动脉非罪犯病变(NCCLs)进展也是影响冠心病患者预后的重要因素,但是残余胆固醇与进展为主要不良心血管事件(MACE)的NCCLs易损斑块的关系尚不明确。目的探讨RC对发生MACE的NCCLs易损斑块的预测价值及长期预后的相关性。方法选取2015年2月—2022年2月于新疆医科大学第一附属医院心脏中心住院的488例冠心病患者为研究对象,通过电子病历系统收集患者基线资料,行冠状动脉造影及光学相干断层扫描OCT。入组患者在出院1、3、6和12个月接受预定随访。采用Spearman秩相关检验探究RC与NCCLs中薄纤维帽粥样硬化斑块(TCFA)斑块特征的相关性。采用多因素Logistic回归分析探究NCCLs中TCFA发生MACE的影响因素。绘制受试者工作特征曲线(ROC曲线)并计算ROC曲线下面积(AUC),探究RC对NCCLs中TCFA发生MACE的预测价值。结果共纳入488例冠心病患者,根据NCCLs是否发生MACE将患者分为发生MACE组(n=38)和未发生MACE组(n=450)。通过OCT识别NCCLs的斑块特征,共分析了749个NCCLs斑块,304个NCCLs斑块最小管腔面积(MLA)<3.5 mm^(2)。随访期间38例(7.8%)患者共发生了41例次NCCLs斑块引起的MACE事件,18例(3.7%)患者发生了支架内再狭窄,15例(3.1%)发生了不确定因素的死亡。发生MACE组患者高血压、糖尿病、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、RC、糖化血红蛋白(Hb A1c)、TCFA、MLA<3.5 mm^(2)比例高于未发生MACE组(P<0.05)。105例患者检查出TCFA,其中22例发生MACE(发生MACE的TCFA组),83例未发生MACE(未发生MACE的TCFA组)。发生MACE的TCFA组糖尿病比例与RC高于未发生MACE的TCFA组(P<0.05)。Spearman秩相关分析结果示,RC与最薄纤维帽厚度、MLA呈负相关(r_(s)=-0.665、-0.771,P<0.05),与最大脂质弧度、巨噬细胞浸润呈正相关(r_(s)=0.806、0.481,P<0.05)。多因素Logistic回归分析结果显示糖尿病(OR=3.410,95%CI=1.165~9.988,P=0.025)、高RC水平(OR=5.879,95%CI=1.436~24.073,P=0.014)是NCCLs中TCFA发生MACE的危险因素。绘制RC预测NCCLs中TCFA发生MACE的ROC曲线,结果显示AUC为0.695(95%CI=0.571~0.819,P=0.005),最佳截断值为0.606 mmol/L,灵敏度、特异度分别为0.818、0.518。结论 RC水平升高可能是冠心病患者中NCCLs易损斑块发生MACE的危险因素,对NCCLs中TCFA发生MACE有一定的预测价值。

关键词：冠心病冠状动脉粥样硬化血脂异常主要不良心血管事件冠状动脉非罪犯病变残余胆固醇相关性研究

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Conditional Generation of Multiparticle Entanglement via Cavity QED

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Communications in Theoretical Physics 2009年第11期52卷 835-839页

作者： XIANG shao-hua shao Bin SONG Ke-Hui Department of Physics and Information Engineering Huaihua University Huaihua 418008 China Research Institute of Information Science Huaihua University Huaihua 418008 China Department of Physics Beijing Institute of Technology Beijing 100081 China

We propose a simple scheme to not only generate GHZ states and W states of the multiparticle but also form a new category of multiparticle entangled states by letting the A-type three-level atoms simultaneously interacting with a coherent cavity field followed by the selective measurements on the cavity mode. We investigate the influence of the cavity dissipation on the generated entangled state and discuss the experimental feasibility of our scheme. It is shown that the intensity of the coherent cavity field plays an instructive role in contribution to state preparation process while the cavity decay and the detuning between the atoms and cavity mode result in the deterioration of the generated entangled state.

关键词： multiparticle entanglement gavity QED decoherence