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A Video Captioning Method by Semantic Topic-Guided Generation
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作者 Ou Ye Xinli Wei +2 位作者 Zhenhua Yu yan fu Ying yang 《Computers, Materials & Continua》 SCIE EI 2024年第1期1071-1093,共23页
In the video captioning methods based on an encoder-decoder,limited visual features are extracted by an encoder,and a natural sentence of the video content is generated using a decoder.However,this kind ofmethod is de... In the video captioning methods based on an encoder-decoder,limited visual features are extracted by an encoder,and a natural sentence of the video content is generated using a decoder.However,this kind ofmethod is dependent on a single video input source and few visual labels,and there is a problem with semantic alignment between video contents and generated natural sentences,which are not suitable for accurately comprehending and describing the video contents.To address this issue,this paper proposes a video captioning method by semantic topic-guided generation.First,a 3D convolutional neural network is utilized to extract the spatiotemporal features of videos during the encoding.Then,the semantic topics of video data are extracted using the visual labels retrieved from similar video data.In the decoding,a decoder is constructed by combining a novel Enhance-TopK sampling algorithm with a Generative Pre-trained Transformer-2 deep neural network,which decreases the influence of“deviation”in the semantic mapping process between videos and texts by jointly decoding a baseline and semantic topics of video contents.During this process,the designed Enhance-TopK sampling algorithm can alleviate a long-tail problem by dynamically adjusting the probability distribution of the predicted words.Finally,the experiments are conducted on two publicly used Microsoft Research Video Description andMicrosoft Research-Video to Text datasets.The experimental results demonstrate that the proposed method outperforms several state-of-art approaches.Specifically,the performance indicators Bilingual Evaluation Understudy,Metric for Evaluation of Translation with Explicit Ordering,Recall Oriented Understudy for Gisting Evaluation-longest common subsequence,and Consensus-based Image Description Evaluation of the proposed method are improved by 1.2%,0.1%,0.3%,and 2.4% on the Microsoft Research Video Description dataset,and 0.1%,1.0%,0.1%,and 2.8% on the Microsoft Research-Video to Text dataset,respectively,compared with the existing video captioning methods.As a result,the proposed method can generate video captioning that is more closely aligned with human natural language expression habits. 展开更多
关键词 Video captioning encoder-decoder semantic topic jointly decoding Enhance-TopK sampling
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Natural history of persistent subretinal fluid following the successful repair of rhegmatogenous retinal detachment 被引量:6
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作者 yan fu Song Chen +3 位作者 Zhao-Hui Gu Yue-Ling Zhang Li-Ying Li Na yang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第10期1621-1628,共8页
AIM:To provide a detailed description of the natural history of persistent subretinal fluid(SRF)after successful repair of rhegmatogenous retinal detachment(RRD)and its association with visual outcome.METHODS:This was... AIM:To provide a detailed description of the natural history of persistent subretinal fluid(SRF)after successful repair of rhegmatogenous retinal detachment(RRD)and its association with visual outcome.METHODS:This was a prospective long-term follow-up for eyes undergoing scleral buckling(SB)surgery for maculaoff RRD.Examinations were carried out preoperatively and postoperatively at 1,3,6,9 and 12 mo,until persistent SRF had completely resolved.One month postoperatively,optical coherence tomography(OCT)was used to classify SRF into three patterns:bleb-like loculated(BL),shallow-diffused(SD),and multiple blebs(MB).Serial OCT imaging was used to evaluate morphological changes in SRF until its complete disappearance.Patients were divided into two groups depending on the presence or absence of persistent SRF.RESULTS:A total of 59 patients(59 eyes)were included.There were no statistical differences between two groups at baseline,except for the proportion of patients with high myopia and a younger age.One month after surgery,OCT detected persistent SRF in 49 eyes(83.1%).The 3 morphological patterns of SRF were observed in 27 eyes(55.1%)with BL,13 eyes(26.5%)with SD,and 9 eyes(18.4%)with MB.The mean time for complete absorption differed significantly across the three SRF patterns(F=8.097,P=0.001),which was 8.8±6.1,20.1±12.1,and 16.7±10.2 mo in BL,SD,and MB,respectively.In 9 of the 13 eyes with SD,the pattern transformed into MB type.In cases involving MB,the size and number of blebs decreased gradually until they had been completely absorbed.Eyes with persistent SRF were more likely to demonstrate disruption of the ellipsoid zone(49.0%vs 10%,P=0.034).The final best-corrected visual acuity of two groups was 0.37±0.11(with SRF)vs 0.34±0.12(without SRF)logMAR(P=0.499),respectively.CONCLUSION:High preoperative myopia and younger age are associated with persistent SRF.BL is the most commonly observed pattern with the shortest duration and gradually disappeared.Most cases involving SD SRF transform into MB type during resolution.The size and number of the MBs decrease gradually until they were completely absorbed.The absence of persistent SRF may contribute to slow visual recovery in the short-term but does not influence the final visual outcome. 展开更多
关键词 subretinal fluid rhegmatogenous retinal detachment optical coherence tomography visual acuity
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A Sentence Retrieval Generation Network Guided Video Captioning
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作者 Ou Ye Mimi Wang +3 位作者 Zhenhua Yu yan fu Shun Yi Jun Deng 《Computers, Materials & Continua》 SCIE EI 2023年第6期5675-5696,共22页
Currently,the video captioning models based on an encoder-decoder mainly rely on a single video input source.The contents of video captioning are limited since few studies employed external corpus information to guide... Currently,the video captioning models based on an encoder-decoder mainly rely on a single video input source.The contents of video captioning are limited since few studies employed external corpus information to guide the generation of video captioning,which is not conducive to the accurate descrip-tion and understanding of video content.To address this issue,a novel video captioning method guided by a sentence retrieval generation network(ED-SRG)is proposed in this paper.First,a ResNeXt network model,an efficient convolutional network for online video understanding(ECO)model,and a long short-term memory(LSTM)network model are integrated to construct an encoder-decoder,which is utilized to extract the 2D features,3D features,and object features of video data respectively.These features are decoded to generate textual sentences that conform to video content for sentence retrieval.Then,a sentence-transformer network model is employed to retrieve different sentences in an external corpus that are semantically similar to the above textual sentences.The candidate sentences are screened out through similarity measurement.Finally,a novel GPT-2 network model is constructed based on GPT-2 network structure.The model introduces a designed random selector to randomly select predicted words with a high probability in the corpus,which is used to guide and generate textual sentences that are more in line with human natural language expressions.The proposed method in this paper is compared with several existing works by experiments.The results show that the indicators BLEU-4,CIDEr,ROUGE_L,and METEOR are improved by 3.1%,1.3%,0.3%,and 1.5%on a public dataset MSVD and 1.3%,0.5%,0.2%,1.9%on a public dataset MSR-VTT respectively.It can be seen that the proposed method in this paper can generate video captioning with richer semantics than several state-of-the-art approaches. 展开更多
关键词 Video captioning encoder-decoder sentence retrieval external corpus RS GPT-2 network model
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基于时空图联合关系路径的行人轨迹预测框架
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作者 孙科 鄢府 +2 位作者 范勇强 牟利平 谢海兵 《无线电工程》 北大核心 2023年第2期281-289,共9页
时空图被广泛应用于行人轨迹预测等时间序列任务中,如何更精确地捕捉不同时间段的轨迹位置信息以及更充分地利用时空图的结构信息对于轨迹预测至关重要。传统的轨迹预测方法规则复杂、约束性强、可扩展性较差,往往只能应用于特定领域。... 时空图被广泛应用于行人轨迹预测等时间序列任务中,如何更精确地捕捉不同时间段的轨迹位置信息以及更充分地利用时空图的结构信息对于轨迹预测至关重要。传统的轨迹预测方法规则复杂、约束性强、可扩展性较差,往往只能应用于特定领域。基于学习的轨迹预测方法不依赖于专家经验的物理规则,根据观察的轨迹数据来学习不同时间段各个空间位置之间的变化规则。基于学习的方法存在一定局限性,如没有充分利用时空图的结构信息,导致轨迹预测模型的性能下降。针对上述问题,提出了一种新型基于时空图联合关系路径的行人轨迹预测框架(Spatio-Temporal Graphs with Relationship Path Trajectory Prediction Framework, STRP-TPF)。STRP-TPF主要包括EdgeRNN和NodeRNN模型。STRP-TPF基于时空图构建关系路径,基于关系路径构建因子图;构建EdgeRNN和NodeRNN模型,并将因子图作为输入;输出下一时刻行人的位置,并且预测完整的行人轨迹。STRP-TPF利用关系路径能够准确捕捉时空图的结构信息,充分学习行人在不同时间和空间点的轨迹关系。大量实验结果表明,在ETH和UCY数据集上,STRP-TPF的整体性能均优于目前最先进的方法。在平均位移误差和最终位移误差方面,STRP-TPF比目前最先进方法低32.6%和37.7%。STRP-TPF的预测轨迹能够更准确地匹配真实轨迹。 展开更多
关键词 时空图 轨迹预测 关系路径 因子图 平均位移误差 最终位移误差
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视网膜脱离行玻璃体切割术后发生视物变形的因素分析 被引量:2
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作者 付燕 张月玲 +3 位作者 顾朝辉 张海江 王丽英 耿任飞 《国际眼科杂志》 CAS 北大核心 2021年第5期906-909,共4页
目的:探讨玻璃体切割(PPV)术后成功复位的孔源性视网膜脱离(RRD)患者发生视物变形的危险因素。方法:回顾性临床研究。纳入2017-01/2019-01在我院确诊的RRD患者94例94眼进行研究。所有患者均行经睫状体平坦部标准23G PPV手术。首次PPV后... 目的:探讨玻璃体切割(PPV)术后成功复位的孔源性视网膜脱离(RRD)患者发生视物变形的危险因素。方法:回顾性临床研究。纳入2017-01/2019-01在我院确诊的RRD患者94例94眼进行研究。所有患者均行经睫状体平坦部标准23G PPV手术。首次PPV后视网膜解剖复位。于PPV术前及术后1、6、12mo,至末次随访,行BCVA、眼压、裂隙灯显微镜、间接检眼镜、视物变形评分表(M-chart表)、OCT检查,并分析发生视物变形的危险因素。结果:术后1mo,94眼中50眼(53%)存在视物变形,视物变形(+)组平均M值为0.68±0.28,累及黄斑和未累及黄斑的RRD患者发生视物变形有差异(P<0.01),术后不同随访时间M值变化有差异(F=26.442,P<0.01)。多因素Logistic回归分析结果显示:视网膜脱离累及黄斑(OR=9.020,95%CI:1.808~45.011,P=0.007)、EZ完整性中断(OR=10.570,95%CI:2.909~38.400,P<0.01)是RRD复位术后视物变形发生的独立影响因素。结论:PPV术后成功复位的RRD患者术后发生视物变形程度逐渐减轻,视网膜脱离累及黄斑和EZ完整性中断是发生视物变形的独立危险因素。 展开更多
关键词 孔源性视网膜脱离 视物变形 光学相干断层扫描 椭圆体带
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基于知识图谱的工艺推理系统 被引量:2
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作者 郭亮 晏釜 +2 位作者 李湉 郑娟 熊吉键 《现代制造工程》 CSCD 北大核心 2021年第10期1-10,共10页
为了企业能够有效、准确地利用专家知识和数据,减少工艺人员的重复性劳动,开发了基于知识图谱的工艺自动推理(决策)系统。该系统利用知识图谱技术构建了三层次工艺信息模型,将工艺知识与设备资源组织在一起,实现了零件/特征级别的工艺... 为了企业能够有效、准确地利用专家知识和数据,减少工艺人员的重复性劳动,开发了基于知识图谱的工艺自动推理(决策)系统。该系统利用知识图谱技术构建了三层次工艺信息模型,将工艺知识与设备资源组织在一起,实现了零件/特征级别的工艺自动决策。该系统采用B/S设计架构,能与Web环境中的其他数据主体无缝集成。通过某航空发动机锥齿轮轴在原型系统中的工艺决策,验证了系统的实用性。 展开更多
关键词 工艺推理 智能系统 知识工程 知识图谱
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新型全球化背景下的保险发展——来自“一带一路”沿线国家的实证研究 被引量:1
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作者 周晶 杨馥 《保险职业学院学报》 2019年第2期5-11,共7页
“一带一路”倡议构建了新型全球化的合作发展平台,为“一带一路”沿线国家在现阶段提供了巨大发展机遇。本文以“一带一路”沿线国家为研究样本,选择2007-2016十年间的面板数据研究全球化对这些国家保险业发展的影响。研究发现,全球化... “一带一路”倡议构建了新型全球化的合作发展平台,为“一带一路”沿线国家在现阶段提供了巨大发展机遇。本文以“一带一路”沿线国家为研究样本,选择2007-2016十年间的面板数据研究全球化对这些国家保险业发展的影响。研究发现,全球化对“一带一路”沿线国家保险业的促进作用非常有限,并且在三个全球化分量指标中,政治全球化的影响最为显著,其次为社会全球化,而经济全球化的影响则最弱,这与发达保险市场的研究结论是不同的,值得思考和关注。 展开更多
关键词 一带一路 全球化 保险
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混沌灰狼优化算法训练多层感知器 被引量:15
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作者 晏福 徐建中 李奉书 《电子与信息学报》 EI CSCD 北大核心 2019年第4期872-879,共8页
灰狼优化算法(GWO)是一种新的基于灰狼捕食行为的元启发式算法,被证明是一种具有高水平的探索和开发能力的算法。但是存在开发和探索不平衡的问题,以至于其优化性能并不理想。该文将混沌理论引入GWO中,用于平衡GWO的探索和开发,提出一... 灰狼优化算法(GWO)是一种新的基于灰狼捕食行为的元启发式算法,被证明是一种具有高水平的探索和开发能力的算法。但是存在开发和探索不平衡的问题,以至于其优化性能并不理想。该文将混沌理论引入GWO中,用于平衡GWO的探索和开发,提出一种改进的混沌灰狼优化算法(CGWO),并应用于多层感知器(MLPs)的训练。首先,基于Cubic混沌理论对GWO的位置更新公式进行改进,以增加个体的多样性,增大跳出局部最优的概率和对解空间进行深入的搜索;其次,设计一种非线性收敛因子,用于协调和平衡CGWO算法在不同迭代进化时期的探索和开发能力;最后,将CGWO算法作为MLPs的训练器,用于对3个复杂分类问题进行分类实验。结果表明:CGWO在分类准确率,避免陷入局部最优,全局收敛速度和鲁棒性方面相较于其他对比算法均具有较好的性能。 展开更多
关键词 灰狼优化算法 混沌理论 非线性收敛因子 多层感知器 分类问题
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Mechanism of immune tolerance induced by donor derived immature dendritic cells in rat high-risk corneal transplantation 被引量:11
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作者 Xiao-Wei Gao yan fu +3 位作者 Wen-Jing Li An-Jie Du Xia Li Xu-Dong Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第3期269-275,共7页
AIM: To study the role of immature dendritic cells (imDCs) on immune tolerance in rat penetrating keratoplasty (PKP) in high -risk eyes and to investigate the mechanism of immune hyporesponsiveness induced by donor-de... AIM: To study the role of immature dendritic cells (imDCs) on immune tolerance in rat penetrating keratoplasty (PKP) in high -risk eyes and to investigate the mechanism of immune hyporesponsiveness induced by donor-derived imDCs. ·METHODS: Seventy-five SD rats (recipient) and 39 Wistar rats (donor) were randomly divided into 3 groups: control, imDC and mature dendritic cell (mDC) group respectively. Using a model of orthotopic corneal transplantation in which allografts were placed in neovascularized high -risk eyes of recipient rat. Corneal neovascularization was induced by alkaline burn in the central cornea of recipient rat. Recipients in imDC group or mDC group were injected donor bone marrow-derived imDCs or mDCs of 1 ×10 6 respectively 1 week before corneal transplantation via tail vein. Control rat received the same volume of PBS. In each group, 16 recipients were kept for determination of survival time and other 9 recipients were executed on day 3, 7 and 14 after transplantation. Cornea was harvested for hematoxylin - eosin staining and acute rejection evaluation, Western blot was used to detect the expression level of Foxp3. ·RESULTS: The mean survival time of imDC group was significantly longer than that of control and mDC groups (all P <0.05). The expression level of Foxp3 on CD4 + CD25 + T cells of imDC group (2.24 ±0.18) was significantly higher than that in the control (1.68 ±0.09) and mDC groups (1.46±0.13) (all P <0.05).·CONCLUSION: Donor -derived imDC is an effective treatment in inducing immune hyporesponsiveness in rat PKP. The mechanism of immune tolerance induced by imDC might be inhibit T lymphocytes responsiveness by regulatory T cells. 展开更多
关键词 IMMATURE dendriti ccell HIGH-RISK KERATOPLASTY REGULATORY T cells
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离散元-有限差分跨尺度耦合下桩与土体稳定性细观数值分析 被引量:1
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作者 高涛 陈云娟 +3 位作者 闫甫 李艳龙 刘效智 王乐宁 《计算机辅助工程》 2021年第3期24-30,共7页
为准确分析桩体宏观变形与周围土颗粒细观力学行为,采用离散元-有限差分的跨尺度耦合进行桩和土体接触过程中的稳定性分析,研究桩下沉过程中周围土体的细观变形、应力分布和桩体自身变化情况,通过FLAC3D建立桩和外部土体有限差分网格单... 为准确分析桩体宏观变形与周围土颗粒细观力学行为,采用离散元-有限差分的跨尺度耦合进行桩和土体接触过程中的稳定性分析,研究桩下沉过程中周围土体的细观变形、应力分布和桩体自身变化情况,通过FLAC3D建立桩和外部土体有限差分网格单元,对桩周围侧土体应用PFC3D离散元建立土颗粒微观结构模型。研究结果表明:离散元与有限差分耦合方案能够模拟桩周围土体细观力学行为;外部区域土体位移场呈包裹式C形对称分布,应力场以竖直应力为主导,离散元土颗粒接触力链网格以树根状向周围递减削弱分布;桩弹性单元体下沉时,应力场和位移场均有分层现象,应力场以压应力为主,但存在局部拉应力即反弹现象。 展开更多
关键词 多尺度耦合 位移场 应力场 接触力链 数值模拟
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Intrauterine cystic adenomyosis:Report of two cases 被引量:7
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作者 yan-yan Fan Yi-Nan Liu +1 位作者 Jia Li yan fu 《World Journal of Clinical Cases》 SCIE 2019年第5期676-683,共8页
BACKGROUND Cystic adenomyosis is a special type of adenomyosis. Its clinical manifestations lack specificity. Pelvic ultrasound and nuclear magnetic resonance imaging can help clarify the diagnosis. Because cystic ute... BACKGROUND Cystic adenomyosis is a special type of adenomyosis. Its clinical manifestations lack specificity. Pelvic ultrasound and nuclear magnetic resonance imaging can help clarify the diagnosis. Because cystic uterine adenomyosis is rare in clinical work, it can be easily misdiagnosed or its diagnosis can be missed. Early surgical treatment and postoperative drug treatment can alleviate dysmenorrhea,menorrhagia, anemia, and other symptoms.CASE SUMMARY Two cases complained about abnormal vaginal bleeding and were diagnosed with intrauterine cystic adenomyosis by gynecological ultrasound and pathological examination. The clinical manifestations included dysmenorrhea,hypermenorrhea, and a history of cesarean section. Both cases underwent a surgery, and chocolate-like liquid was released from the cystic mass in the uterus and the manifestations were relieved.CONCLUSION Intrauterine cystic adenomyosis could be diagnosed by pathological examination and treated by hysterectomy or hystscopy to release the liquid inside. 展开更多
关键词 CYSTIC ADENOMYOSIS ADENOMYOSIS JUNCTIONAL ZONE INTRAUTERINE Case REPORT
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改良四点固定人工晶状体悬吊植入术在无晶状体眼中的有效性及安全性观察
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作者 陈佳菲 顾朝辉 +1 位作者 付燕 李青 《国际眼科杂志》 CAS 北大核心 2022年第10期1757-1760,共4页
目的:观察改良四点固定人工晶状体悬吊植入术在无晶状体眼中的有效性及安全性。方法:前瞻性研究。选2020-10/2021-05于我院行改良四点固定人工晶状体悬吊植入术的无晶状体眼患者32例32眼,平均年龄44.56±8.48岁。观察手术前后裸眼视... 目的:观察改良四点固定人工晶状体悬吊植入术在无晶状体眼中的有效性及安全性。方法:前瞻性研究。选2020-10/2021-05于我院行改良四点固定人工晶状体悬吊植入术的无晶状体眼患者32例32眼,平均年龄44.56±8.48岁。观察手术前后裸眼视力(UCVA)、最佳矫正视力(BCVA)、角膜散光、术中及术后并发症。结果:所有患者平均随访4.84±0.64mo,术前UCVA、(LogMAR)为1.25±0.42,末次随访时为0.5±0.25(P<0.001);术前BCVA(LogMAR)为0.41±0.19,末次随访时为0.42±0.19(P>0.05);术前角膜散光为1.17±0.64D,末次随访时为1.20±0.59D(P>0.05)。术中无并发症发生,术后发生低眼压2眼、高眼压1眼、角膜水肿2眼,无前房积血、玻璃体积血、黄斑囊样水肿、角膜内皮失代偿、人工晶状体倾斜或偏心、缝线外露等并发症。结论:改良四点固定人工晶状体悬吊植入术可显著提高无晶状体眼患者术后视力、未增加额外角膜散光、并发症少。 展开更多
关键词 四点固定 人工晶状体悬吊植入术 无晶状体眼
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Proteomic profiling of early degenerative retina of RCS rats 被引量:2
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作者 Zhi-Hong Zhu yan fu +2 位作者 Chuan-Huang Weng Cong-Jian Zhao Zheng-Qin Yin 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第6期878-889,共12页
AIM: To identify the underlying cellular and molecular changes in retinitis pigmentosa(RP).METHODS: Label-free quantification-based proteomics analysis, with its advantages of being more economic and consisting of sim... AIM: To identify the underlying cellular and molecular changes in retinitis pigmentosa(RP).METHODS: Label-free quantification-based proteomics analysis, with its advantages of being more economic and consisting of simpler procedures, has been used with increasing frequency in modern biological research. Dystrophic RCS rats, the first laboratory animal model for the study of RP, possess a similar pathological course as human beings with the diseases. Thus, we employed a comparative proteomics analysis approach for in-depth proteome profiling of retinas from dystrophic RCS rats and non-dystrophic congenic controls through Linear Trap Quadrupole-orbitrap MS/MS, to identify the significant differentially expressed proteins(DEPs). Bioinformatics analyses, including Gene ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway annotation and upstream regulatory analysis, were then performed on these retina proteins. Finally, a Western blotting experiment was carried out to verify the difference in the abundance of transcript factor E2F1.RESULTS: In this study, we identified a total of 2375 protein groups from the retinal protein samples of RCS rats and non-dystrophic congenic controls. Four hundred thirty-four significantly DEPs were selected by Student's t-test. Based on the results of the bioinformatics analysis, we identified mitochondrial dysfunction and transcription factor E2F1 as the key initiation factors in early retinal degenerative process.CONCLUSION: We showed that the mitochondrial dysfunction and the transcription factor E2F1 substantially contribute to the disease etiology of RP. The results provide a new potential therapeutic approach for this retinal degenerative disease. 展开更多
关键词 网膜的退化 PROTEOMICS 线粒体 E2F1 MaxQuant RCS 老鼠
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Overexpression of estrogen receptor beta alleviates the toxic effects of beta-amyloid protein on PC12 cells via non-hormonal ligands 被引量:1
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作者 Hui Wang Lihui Si +4 位作者 Xiaoxi Li Weiguo Deng Haimiao yang Yuyan yang yan fu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第14期1095-1100,共6页
After binding to the estrogen receptor, estrogen can alleviate the toxic effects of beta-amyloid protein, and thereby exert a therapeutic effect on Alzheimer's disease patients. Estrogen can increase the incidence... After binding to the estrogen receptor, estrogen can alleviate the toxic effects of beta-amyloid protein, and thereby exert a therapeutic effect on Alzheimer's disease patients. Estrogen can increase the incidence of breast carcinoma and endometrial cancer in post-menopausal women, so it is not suitable for clinical treatment of Alzheimer's disease. There is recent evidence that the estrogen receptor can exert its neuroprotective effects without estrogen dependence. Real-time quantitative PCR and flow cytometry results showed that, compared with non-transfected PC12 cells, adenovirus-mediated estrogen receptor β gene-transfected PC12 cells exhibited lower expression of tumor necrosis factor α and interleukin 1β under stimulation with beta-amyloid protein and stronger protection from apoptosis. The Akt-specific inhibitor Abi-2 decreased the anti-inflammatory and anti-apoptotic effects of estrogen receptor β gene-transfection. These findings suggest that overexpression of estrogen receptor β can alleviate the toxic effect of beta-amyloid protein on PC12 cells, without estrogen dependence. The Akt pathway is one of the potential means for the anti-inflammatory and anti-apoptotic effects of the estrogen receptor. 展开更多
关键词 β-淀粉样蛋白 雌激素受体Β PC12细胞 毒性作用 过度表达 神经保护作用 抗凋亡作用 阿尔茨海默氏症
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Comparisons of biophysical properties and bioactivities of mono-PEGylated endostatin and an endostatin analog 被引量:1
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作者 Shan Wang yan fu Yongzhang Luo 《Chinese Journal of Cancer》 SCIE CAS CSCD 2016年第2期61-68,共8页
Background:Endostatin(ES) is a well-established potent endogenous antiangiogenic factor.An ES variant,called zinc-binding protein-ES(ZBP-ES),is clinically available;however,its use is limited by rapid renal clearance ... Background:Endostatin(ES) is a well-established potent endogenous antiangiogenic factor.An ES variant,called zinc-binding protein-ES(ZBP-ES),is clinically available;however,its use is limited by rapid renal clearance and short residence time.PEGylation has been exploited to overcome these shortcomings,and mono-PEGylated ES(called M_2ES) as well as mono-PEGylated ZBP-ES(MZBP-ES) are developed in our study.This study aimed to compare the biophysical properties and biological effects of M_2ES and MZBP-ES to evaluate their druggability.Methods:Circular dichroism and tryptophan emission fluorescence were used to monitor the conformational changes of M_2ES and MZBP-ES.Their resistance to trypsin digestion and guanidinium chloride(GdmCl)-induced unfolding was examined by Coomassie staining and tryptophan emission fluorescence,respectively.The biological effects of M_2ES and MZBP-ES on endothelial cell migration were evaluated using Transwell migration and wound healing assays,and the uptake of M_2ES and MZBP-ES in endothelial cells was also compared by Western blotting and immunofluorescence.Results:Structural analyses revealed that M_2ES has a more compact tertiary structure than MZBP-ES.Moreover,M_2ES was more resistant to trypsin digestion and GdmCI-induced unfolding compared with MZBP-ES.In addition,although M_2ES and MZBP-ES showed comparable levels of inhibiting transwell migration and wound healing of endothelial cells,M_2ES displayed an increased ability to enter cells compared with MZBP-ES,possibly caused by the enhanced interaction with nucleolin.Conclusions:M_2ES has a more compact tertiary structure,is more stable for trypsin digestion and GdmCI-induced unfolding,exhibits increased cellular uptake and shows equivalent inhibitory effects on cell migration relative to MZBP-ES,indicating that M_2ES is a more promising candidate for anticancer drug development compared with MZBP-ES. 展开更多
关键词 Endostatin PEGylation ANTIANGIOGENIC therapy Drug design ZINC-BINDING protein-endostatin
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Effects of aminoguanidine on retinal apoptosis in mice with oxygen-induced retinopathy 被引量:1
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作者 An-Jie Du Bing Ren +3 位作者 Xiao-Wei Gao Lei yang yan fu Xu-Dong Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第4期436-441,共6页
AIM:To explore the protective effects of amino-guanidine(AG) on retinal apoptosis in mice with oxygeninduced retinopathy(OIR).·METHODS:A total of 80 C57BL/6J mice,aged 7 days,were randomly divided into four group... AIM:To explore the protective effects of amino-guanidine(AG) on retinal apoptosis in mice with oxygeninduced retinopathy(OIR).·METHODS:A total of 80 C57BL/6J mice,aged 7 days,were randomly divided into four groups:normal,high oxygen,high oxygen saline and high oxygen treated with AG.In the normal group,mice were housed in normoxic conditions from postnatal day P7 to P17.Mice in the other 3 groups were placed under hyperoxic conditions(75 ±2% O2) in an oxygen-regulated chamber for 5 days and subsequently placed in normoxic conditions for 5days.Mice in the AG group were treated once daily,from P12 to P17,with AG hemisulfate(100mg/kg body weight,intraperitoneally) dissolved in physiological saline.An equivalent amount of 0.9% physiological saline was administered,as above,to mice in the high oxygen saline group.Ten mice were randomly selected from each group on P14 and on P17,euthanized and the retinas examined.Apoptotic cells in the retina were detected using the terminal-deoxynucleoitidyl transferase mediated nick end labeling(TUNEL) method.The expression of nitric oxide synthase(iNOS) in the retina was detected by immunohistochemistry and changes in rod cells were observed using electron microscopy.·RESULTS:TUNEL-positive cells and iNOS immunoreactive neurons were present in the inner nuclear and ganglion cell retinal layers of mice in the high oxygen group.The number of TUNEL-positive cells was significantly greater in the high oxygen group compared with the normal group(t =-20.81,P14d<0.05;t =-15.05,P17d<0.05).However,the number of TUNEL-positive cells in the AG treatment group was significantly lower(t =-13.21,P14d<0.05;t =-6.61,P17d<0.05) compared with thehigh oxygen group.The expression of iNOS was significantly higher in the high oxygen group compared with the normal group(t =-21.95,P14d<0.05;t =-17.30,P17d<0.05).However,the expression of iNOS in the AG treatment group was significantly lower(t =-12.17,P14d<0.05;t =-10.30,P17d<0.05) compared with the high oxygen group.The outer segments of the rods were disorganized and short in the high oxygen group.Rod morphology appeared to be slightly improved in the AG group.·CONCLUSION:AG may protect retinal neurons in OIR by inhibiting apoptosis.The mechanism may be related to iNOS. 展开更多
关键词 AMINOGUANIDINE RETINOPATHY of PREMATURITY APOPTOSIS inhibitor of NITRIC oxide SYNTHASE
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CFD Simulation of the Filtration Performance of Fibrous Filter Considering Fiber Electric Potential Field 被引量:1
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作者 Lei Hou Ayang Zhou +3 位作者 Xiao He Wei Li yan fu Jinli Zhang 《Transactions of Tianjin University》 EI CAS 2019年第5期437-450,共14页
Aiming at disclosing the quantitative e ects of Coulomb forces on the ltration e ciency of aerosol particles, a three- dimensional random ber model was established to describe the microstructure of brous lters. Then, ... Aiming at disclosing the quantitative e ects of Coulomb forces on the ltration e ciency of aerosol particles, a three- dimensional random ber model was established to describe the microstructure of brous lters. Then, computational mod- els including the ow model, particle model, and electric eld model were constructed to estimate the ltration e ciency using the Fluent custom user-de ned function program, neglecting the non-uniformity of the ber potential and the particle charge distribution. The simulation results using the established models agreed with the data in the literature. In particular, the electric eld force was found to be one of the important factors required to improve the ltration e ciency estimation accuracy for the ultra ne particles. Moreover, the variation tendencies of the ltration e ciency and the pressure drop of brous lters were studied based on the in uence factors of the ber potential, particle charge-to-mass ratio, solid volume fraction, ber diameter, and face velocity. The established models and estimated results will provide important guidance on the design of high-e ciency particulate air lters for aerosol particles. 展开更多
关键词 FILTRATION efficiency COULOMB force Three-dimensional random FIBER model INTERCEPTION CAPTURE BROWNIAN diffusion
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Protective effects of umbilical cord mesenchymal stem cell exosomes in a diabetic rat model through live retinal imaging 被引量:1
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作者 yan fu Xiang Gao +4 位作者 Guang-Hui He Song Chen Zhao-Hui Gu Yue-Ling Zhang Li-Ying Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第12期1828-1833,共6页
AIM:To assess the protective effect of human umbilical cord mesenchymal stem cell exosomes(hucMSC-Exs)in a diabetic rat model by using a variety of retinal bioassays.METHODS:hucMSCs were subjected to differential ultr... AIM:To assess the protective effect of human umbilical cord mesenchymal stem cell exosomes(hucMSC-Exs)in a diabetic rat model by using a variety of retinal bioassays.METHODS:hucMSCs were subjected to differential ultracentrifugation for the collection of exosomes,and transmission electron microscopy(TEM),nanoparticle tracking analysis(NTA)using a NanoSight analysis system and Western blotting(WB)were used to analyze the expression of surface marker proteins such as CD63,CD9 and Calnexin.Streptozotocin(STZ)was injected into the intraperitoneal cavity to establish a diabetic model.Rats were divided into a normal group,diabetic group and hucMSC-Ex group.Fundus fluorescein angiography(FFA),optical coherence tomography(OCT)and other live imaging methods were used to observe the fundus of the rats.Finally,the eyeballs of rats from each group were collected for hematoxylin-eosin(HE)staining to further analyze the retinal structure.RESULTS:Through TEM,NTA and WB,we successfully isolated hucMSC-Exs.Subsequent FFA and OCT confirmed that hucMSC-Exs effectively prevented early retinal vascular damage and thickening of the retina.Finally,HE staining of rat retinal sections revealed that exosomes effectively alleviated retinal structure disruption caused by diabetes.CONCLUSION:hucMSC-Exs have a protective effect on the retina in diabetic rat through FFA,OCT and HE staining. 展开更多
关键词 human umbilical cord mesenchymal stem cells EXOSOMES diabetic retinopathy fundus fluorescein angiography optical coherence tomography RAT
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贻贝仿生增韧自愈合聚天冬酰胺/氧化石墨烯凝胶的制备及性能
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作者 付雁 刘华 +2 位作者 刘长玲 王博 杨洪雨 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2022年第5期94-101,共8页
无论从生物医学到水净化系统,刺激响应和自愈合的新型水凝胶材料凭借其多种协同功能,表现出不同的潜在应用。然而,所得材料往往具有明显的弱点和脆性,力学性能欠佳。在这项工作中,提出了一种新型仿生贻贝足丝的改性多巴胺共轭聚天冬酰胺... 无论从生物医学到水净化系统,刺激响应和自愈合的新型水凝胶材料凭借其多种协同功能,表现出不同的潜在应用。然而,所得材料往往具有明显的弱点和脆性,力学性能欠佳。在这项工作中,提出了一种新型仿生贻贝足丝的改性多巴胺共轭聚天冬酰胺(PHEA-DOPA)与氧化石墨烯(GO)构筑的水凝胶(PHEA-DOPA/GO)。以GO纳米片和硼酸(H_(3)BO_(3))作为交联剂,与PHEA-DOPA的极性官能团相互作用。与不含GO的PHEA-DOPA凝胶相比,含有GO的凝胶的储能模量和损耗模量均增加了10倍、拉伸强度增加了1.5倍。此外,含GO的PHEA-DOPA水凝胶表现出快速和自主的自愈合性质,使得该材料成为生物医学中备受青睐的生物相容性水凝胶。 展开更多
关键词 聚天冬酰胺 氧化石墨烯 水凝胶
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蛋白水平日变化饲粮对仔猪生长性能及养分表观消化率的影响
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作者 陈丽丽 兰力伟 +2 位作者 杨福 白忠良 王文杰 《饲料研究》 CAS 北大核心 2020年第8期51-53,共3页
试验旨在研究蛋白水平日变化饲粮对仔猪生长性能及养分表观消化率的影响。试验配制3种能量水平相近、粗蛋白质水平分别为17.0%、18.5%和20.0%的仔猪饲粮。选用21日龄体型体况相似、健康状况良好、平均体重为(6.95±0.06)kg的仔猪90... 试验旨在研究蛋白水平日变化饲粮对仔猪生长性能及养分表观消化率的影响。试验配制3种能量水平相近、粗蛋白质水平分别为17.0%、18.5%和20.0%的仔猪饲粮。选用21日龄体型体况相似、健康状况良好、平均体重为(6.95±0.06)kg的仔猪90头,随机分为3组。对照组全天饲喂蛋白水平为18.5%的饲粮,试验1组早、中、晚分别饲喂蛋白水平为20.0%、18.5%和17.0%的饲粮,试验2组早、中、晚分别饲喂蛋白水平为17.0%、18.5%和20.0%的饲粮。试验期30 d。结果表明:试验1组仔猪平均日增重较对照组提高4.7%,采食量比对照组提高4.7%;试验1组与试验2组仔猪腹泻率分别降低1.63%和0.92%,差异均不显著(P>0.05);与对照组相比,试验1组和试验2组各项营养指标的表观消化率均有提高,试验1组粗蛋白质和粗脂肪的表观消化率显著提高(P<0.05)。结果表明,依据仔猪自身生物节律为仔猪早、中、晚分别提供20.0%、18.5%和17.0%蛋白水平的饲粮可提高其生长性能,降低腹泻发生率,并对营养物质消化产生积极作用。 展开更多
关键词 蛋白水平日变化饲粮 仔猪 生长性能 养分表观消化率
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