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Application of synchrotron source based DEI method in guinea pig cochleae imaging

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Progress in Natural Science:Materials International 2007年第1期17卷 59-67页

作者： YIN Hongxia, LIU Bo, GAO Xin, GAO Xiulai and LUO Shuqian ( College of Biomedical Engineering, capital university of medical sciences, beijing 100069, china Department of Anatomy, capital university of medical sciences, beijing 100069, china) College of Biomedical Engineering Capital University of Medical Sciences Beijing 100069 China Department of Anatomy Capital University of Medical Sciences Beijing 100069 China

Hard X-ray diffraction enhanced imaging (DEI), which is based on a synchrotron source and monochromator-analyzer-crystal system, is an effective method for imaging X-ray phase shift. Utilizing an analyzer crystal with high angular sensitivity of micro-radian, DEI can measure the transmitted, refracted and scattered X-rays when projecting onto a sample. It dramatically improves the contrast and spatial resolution of the resultant images. At the topography station of beijing Synchrotron Radiation Facilities (BSRF), we implemented DEI method in guinea pig cochleae imaging and acquired a series of DEI images. Based on these images, the apparent absorption and refraction images were calculated. The DEI images revealed the holistic spiral structures and inner details of guinea pig cochleae clearly, even including the structures at the cellular level, such as the static cilia of hairy cells and the limbus of Hansen cell. Due to the advantages of high contrast, high spatial resolution and distinct edge-enhanced effect, DEI method promises extensive applications in biology, medicine and clinic in the near future.

关键词： diffraction enhanced imaging hard X-ray imaging phase-contrast imaging cochlea micro-structure synchrotron source.

Growth induction of hepatic stimulator substance in hepatocytes through its regulation on EGF receptors

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Cell Research 1999年第1期9卷 37-49页

作者： AN WEI XIAO JUN LIU TIAN GUANG LEI JIE DAI GUO GUANG DU(Department of Cell Biology, capital university of medical sciences, beijing 100054, china) 1Department of Cell Biology Capital University of Medical Sciences Beijing 100054 China 1Department of Cell Biology Capital University of Medical Sciences Beijing 100054 China 1Department of Cell Biology Capital University of Medical Sciences Beijing 100054 China 1Department of Cell Biology Capital University of Medical Sciences Beijing 100054 China 1Department of Cell Biology Capital University of Medical Sciences Beijing 100054 China

The cytosolic liver-specific growth factor-hepatic stimulator substance (HSS) has been shown to be able to amplify the rat hepatocyte proliferation responded to EGF. In order to get more insight into the mechanism, the regulatory effect of HSS on EGF-receptor(EGF-R) and the receptor phosphorylation at molecular level was studied. HSS partially purified from weanling rat liver was given to cultured hepatocytes and its influence on EGF-R specific binding and internalization as well as mRNA expression were investigated. The results showed that preincubation of hepatocytes with HSS could lead to an increase in [125I]-EGF binding to its receptors and inhibit EGFinduced receptor down-regulation. Furthermore, the overexpression of EGF-R mRNA stimulated by HSS was seen during 2-12 h after the incubation. Additionally, it was demonstrated with human hepatoma sMMC-7721 cells in Western blot that the EGF-R expression and the receptor autophosphorylation were increased with dose/timedependency after HSS treatment. These results strongly suggest that the mechanism of HSS action on hepatocyte growth might be related to its modulation on EGF-R and receptor-mediated signaling transduction.

关键词： EGF receptor hepatic stimulator substance hepatocyte proliferation

Studies on repairing of hemisected thoracic spinal cord of adult rats by using a chitosan tube filled with alginate fibers

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Progress in Natural Science:Materials International 2006年第10期16卷 1051-1055页

作者： LI Xiaoguang, YANG Zhaoyang and YANG Yi ( beijing Center for Neural Regeneration and Repairing, capital university of medical sciences, beijing 100054, china Department of Bioengineering, beijing university of Aeronautics and Astronautics, beijing 100083, china National Center of Biomedical Analysis, beijing 100850, china) [a]beijing Center for Neural Regeneration and Repairing Capital University of Medical Sciences Beijing China [b]Department of Bioengineering Beijing University of Aeronautics and Astronautics Beijing China [c]National Center of Biomedical Analysis Beijing China

A chitosan tube filled with alginate fibers was implanted into the injured spinal cord of a rat for repairing the damaged tissue. Twelve months after the operation, the morphological observation demonstrated that this chitosan tube could induce regeneration of myelinated and non-myelinated axons and blood vessels. The Basso-Beattie-Bresnahan (BBB) behavioral evaluation confirmed that the implants played a key role in the long-term restoration of rats motor functions. It is a promising start in the treatment of the patients with the injury of the spinal cord.

关键词： spinal cord injury regeneration function recovery chitosan alginate behavioral evaluation.

Overexpression of heme oxygenasel protects smooth muscle cells against oxidative injury and inhibits cell proliferation

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Cell Research 2002年第2期12卷 123-132页

作者： MIN ZHANG, BAO HuI ZHANG, LI CHEN, WEI AN1 Institute of Sports Medicine, The Third Hospital, Peking university, beijing 100083, china 2Department of Cell Biology, capital university of medical sciences,{{4., china 1Institute of Sports Medicine The Third Hospital Peking University Beijing 100083 China 1Institute of Sports Medicine The Third Hospital Peking University Beijing 100083 China 2Department of Cell Biology Capital University of Medical Sciences Beijing 100054 China 2Department of Cell Biology Capital University of Medical Sciences Beijing 100054 China

To investigate whether the expression of exogenous heme oxygenase-1 (HO-1) gene within vascular smooth muscle cells (VSMC) could protect the cells from free radical attack and inhibit cell proliferation, we established an in vitro transfection of human HO-1 gene into rat VSMC mediated by a retroviral vector. The results showed that the profound expression of HO-1 protein as well as HO activity was 1.8- and 2.0-fold increased respectively in the transfected cells compared to the non-transfected ones. The treatment of VSMC with different concentrations of H2O2 led to the remarkable cell damage as indicated by survival rate and LDH leakage. However, the resistance of the HO-1 transfected VSMC against H2O2 was significantly raised. This protective effect was dramatically diminished when the transfected VSMC were pretreated with ZnPP-IX, a specific inhibitor of HO, for 24.h. In addition, we found that the growth potential of the transfected cells was significantly inhibited directly by increased activity of H

关键词： Heme oxygenase retroviral vector free radical cell proliferation vascular smooth muscle cells.

Retrovirus-mediated herpes simplex virus thymidine kinase gene therapy approach for hepatocellular carcinoma

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Cell Research 1999年第3期9卷 225-235页

作者： GAO DING CHENG WEI AN JIE DAI(Dcpartment of Cell Biology, capital university of medicalsciences {{4. beijing, china) 1Department of Cell Biology Capital University of Medical Sciences Beijing 100054 China 1Department of Cell Biology Capital University of Medical Sciences Beijing 100054 China 1Department of Cell Biology Capital University of Medical Sciences Beijing 100054 China

The therapeutic effect of herpes simplex virus thymi-dine kinase/ganciclovir (HSV-tk/GCV) system on hepa-tocellular carcinoma was studied in this experimeflt. Thetk-containing retroviral recombinants were used to infecthepatoma cells (BEL-74.2) and the cells were treated withganciclovir (0-1000 pg/ml). The results showed that HSV-tk gene could be efficielltly transferred in Vitro into hep-atoma cells and stably expressed. The growth potentialof the tk-containing cells was significantly inhibited byGCV (P<0.01) as compared to the non-tk-containing *** antitumor effect of HSV-tk/GCV system was also pro-duced ex vivo in tk-containing tumor of nude mice as char-acterized by a marked decrease in tumor growth after GCVtreatment contrary to a progressive enlargement of non-tk-containing tumors. Although the histological examinationdemonstrated that the efficiency of the gene transfer wasless than 30%, the killing effect of HSV-tk/GCV systemon hepatocellular carcinoma was still significantIy gener-ated. The proper mechanism of HSV-tk gene therapy onhepatic tumor referred as "bystander effect" in therapeu-tic approach has not been found in this study and requiredto be explored further.

关键词： HSV-tk retrovirus gene therapy hepatocellular carcinoma

Mutagenicity and Induction of Drug-metabolizing Enzyme Activity by LPG Combustion Particulates in Rats

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Biomedical and Environmental sciences 1994年第4期7卷 346-356页

作者： YIN XUE-JUN LIU JUN-ZHUO LI YONG-SHUN KONG XIANG-HUAN AND LIU HONG(Department of Environmental Health, capital university of medical sciences, beijing 100054, china Department of Environmental Health, beijing {{4. university, beijing, china) Department of Environmental Health Capital University of Medical Sciences Beijing China.

Methylene chloride extracts of particulates from liquefied petroleum gas (LPG) combustion appliance were studied by using Ames test, micronucleus test and inducibility of pulmonary and hepatic aryl hydrocarbon hydroxylase (AHH) and glutathione S-transferase (GST) in rats. The extracts showed mutagenicity for Salmonella typhimurium strain TA98 and its derivatives TA98NR and TA98/1,8-DNP6 with or without S9 mix. The revertants in strains TA98NR and TA98/1,8-DNP6 were less than 4.% and 50% of that in strain TA98 without S9 mix, respectively. Positive results were obtained in mouse bone marrow micronucleus assay. Intratracheal instillation of the extracts led to increase in pulmonary (but not hepatic) AHH and GST activities in rats. It was seen that AHH was more sensitive than GST to induction by the extracts

关键词： Activity Mutagenicity and Induction of Drug-metabolizing Enzyme Activity by LPG Combustion Particulates in Rats DNP LPG

Spinal processing of bee venom-induced pain and hyperalgesia

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生理学报 2008年第5期60卷 645-652页

作者： Jun CHEN Institute for Biomedical sciences of Pain and Institute for Functional Brain Disorders,Tangdu Hospital,the Fourth Military medical university,Xi’an 710038,{{4. Institute for Biomedical sciences of Pain,capital medical university,beijing 100069,{{4. Institute for Biomedical sciences of Pain and Institute for Functional Brain Disorders Tangdu Hospital the Fourth Military Medical University Xi'an 710038

Subcutaneous injection of bee venom causes long-term neural activation and hypersensitization in the dorsal horn of the spinal cord,which contributes to the development and maintenance of various pain-related *** unique behavioral 'phenotypes' of nociception and hypersensitivity identified in the rodent bee venom test are believed to reflect a complex pathological state of inflammatory pain and might be appropriate to the study of phenotype-based mechanisms of pain and *** this review,the spinal processing of the bee venom-induced different 'phenotypes' of pain and hyperalgesia will be *** accumulative electrophysiological,pharmacological,and behavioral data strongly suggest that different 'phenotypes' of pain and hyperalgesia are mediated by different spinal signaling *** the phenotype-based mechanisms of pain might be useful in development of novel therapeutic drugs against complex clinic pathological pain.

关键词：脊髓痛觉过敏蜂毒疼痛治疗方法

Recommendation Method for Contrastive Enhancement of Neighborhood Information

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Computers, Materials & Continua 2024年第1期78卷 453-472页

作者： Hairong Wang beijing Zhou Lisi Zhang He Ma School of Computer Science and Engineering North Minzu UniversityNingxia750021China

Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation ***,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge *** tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge ***,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and ***,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view *** paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge ***,this paper introduces multi-task learning to mitigate the problem of weak supervisory *** validate the effectiveness of our method,experiments are conducted on theMovieLens-1M,MovieLens-20M,Book-Crossing,and Last-FM *** results showthat compared to the best baselines,our method shows significant improvements in AUC and F1.

关键词： Contrastive learning knowledge graph recommendation method

Synthesis and Electrical Conductivity of MDA[Ni(dmit)_2]_2

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Chinese Chemical Letters 1997年第10期8卷 917-918页

作者： Shu Qing SUN Xiao Yin XU Qi Chun ZHANG Pei Ji WU Dao Ben ZHU(Institule of Chemistry. Chinese Academy of sciences. beijing 100080)(Basic School of medical sciences.{{4.. beijing 100054) Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Basic School of medical sciences Cap. University of Medical Sciences Beijing 100054 China

Single crystals of MDA[Ni(dmit)2]2 were synthesized by using electrooxidation *** conductivity measurements exhibit a semiconducting feature with high conductivity at roomtemperature

关键词： MDA dmit Wang Synthesis and Electrical Conductivity of MDA[Ni