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ACtriplet:An improved deep learning model for activity cliffs prediction by integrating triplet loss and pre-training 被引量:1
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作者 Xinxin Yu Yimeng Wang +3 位作者 Long Chen Weihua Li Yun Tang Guixia Liu 《Journal of Pharmaceutical Analysis》 2025年第8期1837-1847,共11页
Activity cliffs(ACs)are generally defined as pairs of similar compounds that only differ by a minor structural modification but exhibit a large difference in their binding affinity for a given target.ACs offer crucial... Activity cliffs(ACs)are generally defined as pairs of similar compounds that only differ by a minor structural modification but exhibit a large difference in their binding affinity for a given target.ACs offer crucial insights that aid medicinal chemists in optimizing molecular structures.Nonetheless,they also form a major source of prediction error in structure-activity relationship(SAR)models.To date,several studies have demonstrated that deep neural networks based on molecular images or graphs might need to be improved further in predicting the potency of ACs.In this paper,we integrated the triplet loss in face recognition with pre-training strategy to develop a prediction model ACtriplet,tailored for ACs.Through extensive comparison with multiple baseline models on 30 benchmark datasets,the results showed that ACtriplet was significantly better than those deep learning(DL)models without pretraining.In addition,we explored the effect of pre-training on data representation.Finally,the case study demonstrated that our model's interpretability module could explain the prediction results reasonably.In the dilemma that the amount of data could not be increased rapidly,this innovative framework would better make use of the existing data,which would propel the potential of DL in the early stage of drug discovery and optimization. 展开更多
关键词 Activity cliff Triplet loss Deep learning pre-training
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Effective distributed convolutional neural network architecture for remote sensing images target classification with a pre-training approach 被引量:3
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作者 LI Binquan HU Xiaohui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第2期238-244,共7页
How to recognize targets with similar appearances from remote sensing images(RSIs) effectively and efficiently has become a big challenge. Recently, convolutional neural network(CNN) is preferred in the target classif... How to recognize targets with similar appearances from remote sensing images(RSIs) effectively and efficiently has become a big challenge. Recently, convolutional neural network(CNN) is preferred in the target classification due to the powerful feature representation ability and better performance. However,the training and testing of CNN mainly rely on single machine.Single machine has its natural limitation and bottleneck in processing RSIs due to limited hardware resources and huge time consuming. Besides, overfitting is a challenge for the CNN model due to the unbalance between RSIs data and the model structure.When a model is complex or the training data is relatively small,overfitting occurs and leads to a poor predictive performance. To address these problems, a distributed CNN architecture for RSIs target classification is proposed, which dramatically increases the training speed of CNN and system scalability. It improves the storage ability and processing efficiency of RSIs. Furthermore,Bayesian regularization approach is utilized in order to initialize the weights of the CNN extractor, which increases the robustness and flexibility of the CNN model. It helps prevent the overfitting and avoid the local optima caused by limited RSI training images or the inappropriate CNN structure. In addition, considering the efficiency of the Na¨?ve Bayes classifier, a distributed Na¨?ve Bayes classifier is designed to reduce the training cost. Compared with other algorithms, the proposed system and method perform the best and increase the recognition accuracy. The results show that the distributed system framework and the proposed algorithms are suitable for RSIs target classification tasks. 展开更多
关键词 convolutional NEURAL network (CNN) DISTRIBUTED architecture REMOTE SENSING images (RSIs) TARGET classification pre-training
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Knowledge Enhanced Pre-Training Model for Vision-Language-Navigation Task 被引量:1
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作者 HUANG Jitao ZENG Guohui +3 位作者 HUANG Bo GAO Yongbin LIU Jin SHI Zhicai 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2021年第2期147-155,共9页
Vision-Language-Navigation(VLN) task is a cross-modality task that combines natural language processing and computer vision. This task requires the agent to automatically move to the destination according to the natur... Vision-Language-Navigation(VLN) task is a cross-modality task that combines natural language processing and computer vision. This task requires the agent to automatically move to the destination according to the natural language instruction and the observed surrounding visual information. To make the best decision, in every step during the navigation, the agent should pay more attention to understanding the objects, the object attributes, and the object relationships. But most current methods process all received textual and visual information equally. Therefore, this paper integrates more detailed semantic connections between visual and textual information through three pre-training tasks(object prediction, object attributes prediction, and object relationship prediction). The model will learn better fusion representation and alignment between these two types of information to improve the success rate(SR) and generalization. The experiments show that compared with the former baseline models, the SR on the unseen validation set(Val Unseen) increased by 7%, and the SR weighted by path length(SPL) increased by 7%;the SR on the test set(Test) increased 4%, SPL increased by 3%. 展开更多
关键词 pre-training cross-modality deep learning scene graph
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基于杆状病毒Bac-to-Bac系统的VLP递送mRNA疫苗平台的建立
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作者 马莉莉 王琼娴 +5 位作者 王晓丽 马孙婷 吕立新 徐彬 冯志新 欧阳伟 《中国动物传染病学报》 北大核心 2025年第5期41-50,共10页
噬菌体MS2 VLP(噬菌体病毒样颗粒)是不含病毒遗传物质的纳米颗粒,可以自组装成一个二十面体衣壳,适合靶向传递RNA。本研究利用Bac-to-Bac系统(杆状病毒表达系统)生产MS2 VLP包裹的eGFP mRNA。分别设计、合成MS2 VLP的表达框和eGFP mRNA... 噬菌体MS2 VLP(噬菌体病毒样颗粒)是不含病毒遗传物质的纳米颗粒,可以自组装成一个二十面体衣壳,适合靶向传递RNA。本研究利用Bac-to-Bac系统(杆状病毒表达系统)生产MS2 VLP包裹的eGFP mRNA。分别设计、合成MS2 VLP的表达框和eGFP mRNA的表达框,将MS2 VLP的表达框和eGFP mRNA的表达框同时插入pFastBac Dual载体中,获得重组供体质粒pFastBacDual-MS2-eGFP mRNA。转化DH10Bac感受态,通过三抗和蓝白斑(卡拉霉素/庆大霉素/四环素/IPTG/X-Gal)筛选以及PCR鉴定,获得重组的rBacmid-MS2-eGFP mRNA。将rBacmid-MS2-eGFP mRNA转染sf9昆虫细胞,获得重组杆状病毒vBacmid-MS2-eGFP mRNA。通过倒置荧光显微镜观察及Western blot检测表明eGFP获得表达。用vBacmid-MS2-eGFP mRNA感染High 5悬浮细胞进行MS2-eGFP mRNA的大量表达,经超速离心纯化,电镜观察可见大量的直径约30 nm的病毒样颗粒(VLP)。提取纯化的MS2 VLP中包裹的mRNA,通过RT-PCR及测序鉴定,结果表明MS2 VLP中包裹的mRNA为eGFP mRNA。将MS2-eGFP mRNA免疫BALB/c小鼠,进行免疫原性研究,通过ELISA测得的抗体效价为1∶819200,表明MS2-eGFP mRNA可以刺激小鼠产生较强的抗原特异性抗体应答。以上结果表明,利用杆状病毒Bac-to-Bac表达系统生产的MS2 VLP可以包裹外源mRNA,并可将外源mRNA递送到小鼠体内产生特异性体液免疫反应。本研究建立了基于杆状病毒Bac-to-Bac表达系统的VLP递送mRNA疫苗研究平台,为今后动物传染病的mRNA疫苗研发提供新的参考。 展开更多
关键词 BAC-TO-BAC MS2 vlp 递送系统 mRNA疫苗
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O型口蹄疫病毒VLPs疫苗抗体竞争ELISA检测方法的建立 被引量:2
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作者 刘玲 戴伶俐 +7 位作者 李晓艳 付玲芳 康斌 董鹏 武玉梅 尹忠良 吴蒙 李雪峰 《中国兽医杂志》 北大核心 2025年第6期60-66,共7页
为实现对口蹄疫病毒(FMDV)类病毒颗粒(VLPs)疫苗免疫效果的有效评估,建立一种O型FMDV VLPs疫苗抗体竞争酶联免疫吸附测定(ELISA)检测方法。本试验以O型FMDV VLPs作为免疫原免疫小鼠制备单克隆抗体,通过O型FMDV VLPs和O型FMDV灭活疫苗抗... 为实现对口蹄疫病毒(FMDV)类病毒颗粒(VLPs)疫苗免疫效果的有效评估,建立一种O型FMDV VLPs疫苗抗体竞争酶联免疫吸附测定(ELISA)检测方法。本试验以O型FMDV VLPs作为免疫原免疫小鼠制备单克隆抗体,通过O型FMDV VLPs和O型FMDV灭活疫苗抗原筛选,ELISA四参数拟合曲线判定,确定最佳单抗。将O型FMDV VLPs作为包被抗原,辣根过氧化物酶(HRP)标记特异性单抗与被检血清竞争结合,通过优化确定O型FMDV VLPs最佳包被浓度、HRP标记特异性单抗最佳工作浓度和最适封闭液,经计算确定判定标准,并进一步分析该竞争ELISA方法的敏感性和特异性;采用建立的方法检测90份O型FMDV VLPs疫苗免疫猪血清样品,验证其实用性。结果显示,O型FMDV VLPs特异性单抗为1D3单抗,该竞争ELISA检测方法的最佳工作条件为:O型FMDV VLPs最佳包被浓度为0.2μg/mL,HRP标记1D3单抗最佳工作浓度为1∶1000,最适封闭液为1%明胶。竞争ELISA判定标准为:被检血清阻断率≥40%,判为阳性;被检血清阻断率≤32%,判为阴性;被检血清阻断率介于32%~40%,则应在14 d后对动物进行重新检测。敏感性和特异性试验结果显示,建立方法的最低检测限为血清效价1∶1000,仅有O型FMDV VLPs疫苗免疫阳性血清能发生竞争性结合,O型和A型FMDV灭活疫苗免疫猪阳性血清无竞争性结合。90份O型FMDV VLPs疫苗免疫猪血清样品的阻断率结果符合体液免疫应答的一般规律,证明该方法可以有效评估O型FMDV VLPs疫苗免疫后血清抗体水平。本试验建立的FMDV VLPs疫苗抗体竞争ELISA检测方法可为开发更多VLPs疫苗检测技术提供技术支撑。 展开更多
关键词 O型口蹄疫 类病毒颗粒(vlps) 竞争ELISA
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Pre-training Assessment Through the Web
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作者 Kenneth Wong Reggie Kwan Jimmy SF Chan 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期297-,共1页
Web-based training is growing quickly in popularit y for professionals in industrial organizations and large enterprises. The savings in cost and time are significant. The instructor-led trainings are bounded by time ... Web-based training is growing quickly in popularit y for professionals in industrial organizations and large enterprises. The savings in cost and time are significant. The instructor-led trainings are bounded by time and place, not to mention the cost involved in traveling, accommodation and training venue. However, in the most online training courses, all trainees are given same training materials and teaching paradigms. The problem of differentia ting the trainees’ abilities is the main concern. We need a pre-training test t o identify and classify of the weaknesses and strengths of differentiate trainee s so as to devise an appropriate training programs for the trainees. Adaptation of a Web-based Computer adaptive Test (CAT) for the pre-training test make the web-based training more efficient. The advantages of CAT are self-pacing, eff iciency, time and cost saving, immediate scoring and feedback, accuracy and secu rity, etc (Rudner, 1998; UMN, 1999; Novell, 2000; Linacre, 2000; Windowsglore, 2 000). Moreover, Web-based CAT also gives greater flexibility and convenience. T his paper describes how this CAT tool is built, how it helps instructor identify the strengths and weaknesses of trainees, and how to assure quality on the CAT system. 展开更多
关键词 CAT TEST pre-training Assessment Through the Web
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A Modified CycleGAN for Multi-Organ Ultrasound Image Enhancement via Unpaired Pre-Training
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作者 Haonan Han Bingyu Yang +2 位作者 Weihang Zhang Dongwei Li Huiqi Li 《Journal of Beijing Institute of Technology》 EI CAS 2024年第3期194-203,共10页
Handheld ultrasound devices are known for their portability and affordability,making them widely utilized in underdeveloped areas and community healthcare for rapid diagnosis and early screening.However,the image qual... Handheld ultrasound devices are known for their portability and affordability,making them widely utilized in underdeveloped areas and community healthcare for rapid diagnosis and early screening.However,the image quality of handheld ultrasound devices is not always satisfactory due to the limited equipment size,which hinders accurate diagnoses by doctors.At the same time,paired ultrasound images are difficult to obtain from the clinic because imaging process is complicated.Therefore,we propose a modified cycle generative adversarial network(cycleGAN) for ultrasound image enhancement from multiple organs via unpaired pre-training.We introduce an ultrasound image pre-training method that does not require paired images,alleviating the requirement for large-scale paired datasets.We also propose an enhanced block with different structures in the pre-training and fine-tuning phases,which can help achieve the goals of different training phases.To improve the robustness of the model,we add Gaussian noise to the training images as data augmentation.Our approach is effective in obtaining the best quantitative evaluation results using a small number of parameters and less training costs to improve the quality of handheld ultrasound devices. 展开更多
关键词 ultrasound image enhancement handheld devices unpaired images pre-train and finetune cycleGAN
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GeoNER:Geological Named Entity Recognition with Enriched Domain Pre-Training Model and Adversarial Training
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作者 MA Kai HU Xinxin +4 位作者 TIAN Miao TAN Yongjian ZHENG Shuai TAO Liufeng QIU Qinjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1404-1417,共14页
As important geological data,a geological report contains rich expert and geological knowledge,but the challenge facing current research into geological knowledge extraction and mining is how to render accurate unders... As important geological data,a geological report contains rich expert and geological knowledge,but the challenge facing current research into geological knowledge extraction and mining is how to render accurate understanding of geological reports guided by domain knowledge.While generic named entity recognition models/tools can be utilized for the processing of geoscience reports/documents,their effectiveness is hampered by a dearth of domain-specific knowledge,which in turn leads to a pronounced decline in recognition accuracy.This study summarizes six types of typical geological entities,with reference to the ontological system of geological domains and builds a high quality corpus for the task of geological named entity recognition(GNER).In addition,Geo Wo BERT-adv BGP(Geological Word-base BERTadversarial training Bi-directional Long Short-Term Memory Global Pointer)is proposed to address the issues of ambiguity,diversity and nested entities for the geological entities.The model first uses the fine-tuned word granularitybased pre-training model Geo Wo BERT(Geological Word-base BERT)and combines the text features that are extracted using the Bi LSTM(Bi-directional Long Short-Term Memory),followed by an adversarial training algorithm to improve the robustness of the model and enhance its resistance to interference,the decoding finally being performed using a global association pointer algorithm.The experimental results show that the proposed model for the constructed dataset achieves high performance and is capable of mining the rich geological information. 展开更多
关键词 geological named entity recognition geological report adversarial training confrontation training global pointer pre-training model
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KitWaSor:Pioneering pre-trained model for kitchen waste sorting with an innovative million-level benchmark dataset
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作者 Leyuan Fang Shuaiyu Ding +3 位作者 Hao Feng Junwu Yu Lin Tang Pedram Ghamisi 《CAAI Transactions on Intelligence Technology》 2025年第1期94-114,共21页
Intelligent sorting is an important prerequisite for the full quantitative consumption and harmless disposal of kitchen waste.The existing object detection method based on an ImageNet pre-trained model is an effective... Intelligent sorting is an important prerequisite for the full quantitative consumption and harmless disposal of kitchen waste.The existing object detection method based on an ImageNet pre-trained model is an effective way of sorting.Owing to significant domain gaps between natural images and kitchen waste images,it is difficult to reflect the characteristics of diverse scales and dense distribution in kitchen waste based on an ImageNet pre-trained model,leading to poor generalisation.In this article,the authors propose the first pre-trained model for kitchen waste sorting called KitWaSor,which combines both contrastive learning(CL)and masked image modelling(MIM)through self-supervised learning(SSL).First,to address the issue of diverse scales,the authors propose a mixed masking strategy by introducing an incomplete masking branch based on the original random masking branch.It prevents the complete loss of small-scale objects while avoiding excessive leakage of large-scale object pixels.Second,to address the issue of dense distribution,the authors introduce semantic consistency constraints on the basis of the mixed masking strategy.That is,object semantic reasoning is performed through semantic consistency constraints to compensate for the lack of contextual information.To train KitWaSor,the authors construct the first million-level kitchen waste dataset across seasonal and regional distributions,named KWD-Million.Extensive experiments show that KitWaSor achieves state-of-the-art(SOTA)performance on the two most relevant downstream tasks for kitchen waste sorting(i.e.image classification and object detection),demonstrating the effectiveness of the proposed KitWaSor. 展开更多
关键词 contrastive learning kitchen waste masked image modeling pre-trained model self-supervised learning
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DPCIPI: A pre-trained deep learning model for predicting cross-immunity between drifted strains of Influenza A/H3N2
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作者 Yiming Du Zhuotian Li +8 位作者 Qian He Thomas Wetere Tulu Kei Hang Katie Chan Lin Wang Sen Pei Zhanwei Du Zhen Wang Xiao-Ke Xu Xiao Fan Liu 《Journal of Automation and Intelligence》 2025年第2期115-124,共10页
Predicting cross-immunity between viral strains is vital for public health surveillance and vaccine development.Traditional neural network methods,such as BiLSTM,could be ineffective due to the lack of lab data for mo... Predicting cross-immunity between viral strains is vital for public health surveillance and vaccine development.Traditional neural network methods,such as BiLSTM,could be ineffective due to the lack of lab data for model training and the overshadowing of crucial features within sequence concatenation.The current work proposes a less data-consuming model incorporating a pre-trained gene sequence model and a mutual information inference operator.Our methodology utilizes gene alignment and deduplication algorithms to preprocess gene sequences,enhancing the model’s capacity to discern and focus on distinctions among input gene pairs.The model,i.e.,DNA Pretrained Cross-Immunity Protection Inference model(DPCIPI),outperforms state-of-theart(SOTA)models in predicting hemagglutination inhibition titer from influenza viral gene sequences only.Improvement in binary cross-immunity prediction is 1.58%in F1,2.34%in precision,1.57%in recall,and 1.57%in Accuracy.For multilevel cross-immunity improvements,the improvement is 2.12%in F1,3.50%in precision,2.19%in recall,and 2.19%in Accuracy.Our study showcases the potential of pre-trained gene models to improve predictions of antigenic variation and cross-immunity.With expanding gene data and advancements in pre-trained models,this approach promises significant impacts on vaccine development and public health. 展开更多
关键词 Cross-immunity prediction pre-trained model Deep learning Influenza strains Hemagglutination inhibition
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Big Texture Dataset Synthesized Based on Gradient and Convolution Kernels Using Pre-Trained Deep Neural Networks
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作者 Farhan A.Alenizi Faten Khalid Karim +1 位作者 Alaa R.Al-Shamasneh Mohammad Hossein Shakoor 《Computer Modeling in Engineering & Sciences》 2025年第8期1793-1829,共37页
Deep neural networks provide accurate results for most applications.However,they need a big dataset to train properly.Providing a big dataset is a significant challenge in most applications.Image augmentation refers t... Deep neural networks provide accurate results for most applications.However,they need a big dataset to train properly.Providing a big dataset is a significant challenge in most applications.Image augmentation refers to techniques that increase the amount of image data.Common operations for image augmentation include changes in illumination,rotation,contrast,size,viewing angle,and others.Recently,Generative Adversarial Networks(GANs)have been employed for image generation.However,like image augmentation methods,GAN approaches can only generate images that are similar to the original images.Therefore,they also cannot generate new classes of data.Texture images presentmore challenges than general images,and generating textures is more complex than creating other types of images.This study proposes a gradient-based deep neural network method that generates a new class of texture.It is possible to rapidly generate new classes of textures using different kernels from pre-trained deep networks.After generating new textures for each class,the number of textures increases through image augmentation.During this process,several techniques are proposed to automatically remove incomplete and similar textures that are created.The proposed method is faster than some well-known generative networks by around 4 to 10 times.In addition,the quality of the generated textures surpasses that of these networks.The proposed method can generate textures that surpass those of someGANs and parametric models in certain image qualitymetrics.It can provide a big texture dataset to train deep networks.A new big texture dataset is created artificially using the proposed method.This dataset is approximately 2 GB in size and comprises 30,000 textures,each 150×150 pixels in size,organized into 600 classes.It is uploaded to the Kaggle site and Google Drive.This dataset is called BigTex.Compared to other texture datasets,the proposed dataset is the largest and can serve as a comprehensive texture dataset for training more powerful deep neural networks and mitigating overfitting. 展开更多
关键词 Big texture dataset data generation pre-trained deep neural network
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Multilingual Text Summarization in Healthcare Using Pre-Trained Transformer-Based Language Models
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作者 Josua Käser Thomas Nagy +1 位作者 Patrick Stirnemann Thomas Hanne 《Computers, Materials & Continua》 2025年第4期201-217,共17页
We analyze the suitability of existing pre-trained transformer-based language models(PLMs)for abstractive text summarization on German technical healthcare texts.The study focuses on the multilingual capabilities of t... We analyze the suitability of existing pre-trained transformer-based language models(PLMs)for abstractive text summarization on German technical healthcare texts.The study focuses on the multilingual capabilities of these models and their ability to perform the task of abstractive text summarization in the healthcare field.The research hypothesis was that large language models could perform high-quality abstractive text summarization on German technical healthcare texts,even if the model is not specifically trained in that language.Through experiments,the research questions explore the performance of transformer language models in dealing with complex syntax constructs,the difference in performance between models trained in English and German,and the impact of translating the source text to English before conducting the summarization.We conducted an evaluation of four PLMs(GPT-3,a translation-based approach also utilizing GPT-3,a German language Model,and a domain-specific bio-medical model approach).The evaluation considered the informativeness using 3 types of metrics based on Recall-Oriented Understudy for Gisting Evaluation(ROUGE)and the quality of results which is manually evaluated considering 5 aspects.The results show that text summarization models could be used in the German healthcare domain and that domain-independent language models achieved the best results.The study proves that text summarization models can simplify the search for pre-existing German knowledge in various domains. 展开更多
关键词 Text summarization pre-trained transformer-based language models large language models technical healthcare texts natural language processing
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VLP/CVD低温硅外延 被引量:3
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作者 谢自力 陈桂章 +1 位作者 洛红 严军 《微电子学》 CAS CSCD 北大核心 2001年第5期357-359,共3页
研究了 VLP/ CVD低温硅外延生长技术。利用自制的 VLP/ CVD设备 ,在低温条件下 ,成功地研制出晶格结构完好的硅同质结外延材料。扩展电阻、X射线衍射谱和电化学分布研究表明 ,在低温下 (T<80 0°C)应用 VLP/ CVD技术 ,可以生长... 研究了 VLP/ CVD低温硅外延生长技术。利用自制的 VLP/ CVD设备 ,在低温条件下 ,成功地研制出晶格结构完好的硅同质结外延材料。扩展电阻、X射线衍射谱和电化学分布研究表明 ,在低温下 (T<80 0°C)应用 VLP/ CVD技术 ,可以生长结构完好的硅外延材料 ; 展开更多
关键词 低温外延 vlp/CVD 杂质分布 半导体技术
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利用重组HPV16L1抗原检测宫颈癌抗L1或VLP抗体的对比 被引量:3
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作者 栾怡 于修平 +5 位作者 宋长芹 卞继峰 赵蔚明 贾继辉 周亚滨 齐眉 《中国病毒学》 CSCD 2002年第4期308-311,共4页
为了评价重组大肠杆菌表达的HPV16L1蛋白和重组腺病毒表达的HPV16L1 VLP两种抗原在检测宫颈癌抗 16L1或VLP抗体及在宫颈癌血清学诊断意义上的差别 ,应用PCR技术从宫颈癌组织的DNA中扩增出全长15 35bp的HPV16L1基因片段 ,克隆至 pUC18 T... 为了评价重组大肠杆菌表达的HPV16L1蛋白和重组腺病毒表达的HPV16L1 VLP两种抗原在检测宫颈癌抗 16L1或VLP抗体及在宫颈癌血清学诊断意义上的差别 ,应用PCR技术从宫颈癌组织的DNA中扩增出全长15 35bp的HPV16L1基因片段 ,克隆至 pUC18 T载体中 ,进行DNA测序鉴定。然后 ,将HPV16L1基因克隆至pGEX 2T表达载体中 ,并诱导表达HPV16L1融合蛋白 ,分子量为 83kD ,能被HPV16L1单克隆抗体所识别。经GST柱层析法纯化后 ,与重组腺病毒表达的HPV16L1 VLP分别经酶联免疫吸附 (ELISA)法检测 12份宫颈癌患者和 35份献血员血清。 12例宫颈癌血清标本中 ,抗HPV16L1蛋白的抗体阳性率为 7例 (占 5 8.3% ) ;抗HPV16L1 VLP的抗体阳性率为 8例 (占 6 6 .7% )。经大肠杆菌表达的重组抗原HPV16L1检测为HPV16抗体IgG(+)的 7份患者血清 ,利用HPV16L1 VLP试剂盒检测均阳性 ;经大肠杆菌表达的重组抗原检测为HPV16抗体IgG( )的 5份患者血清 ,利用HPV16L1 VLP试剂盒检测有 1份阳性。两者对HPV16抗体的阳性检出率并无显著差异 (P >0 .0 5 )。本实验结果说明HPV16与宫颈癌高度相关 ,利用大肠杆菌表达的重组抗原HPV16L1和HPV16L1 VLP重组抗原检测抗体的敏感性并不受影响。利用重组抗原HPV16L1对宫颈癌的抗体进行定性。 展开更多
关键词 重组HPV16L1抗原 检测 宫颈癌 抗L1 vlp抗体 对比 人乳头瘤病毒
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RHDV VLPs单克隆抗体的制备及其识别表位的初步定位 被引量:1
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作者 宋艳华 胡波 +5 位作者 范志宇 彭伟 魏后军 薛家宾 徐为中 王芳 《华北农学报》 CSCD 北大核心 2015年第5期65-70,共6页
为了筛选兔出血症病毒(RHDV)衣壳蛋白(VP60)的特异性单抗,并进一步分析单抗识别表位的分布情况,将重组杆状病毒r Ac V-Bac-VP60接种Sf9昆虫细胞,收获细胞培养物,电镜观察显示重组VP60蛋白获得有效表达,并可组装成病毒样粒子(VLPs)。将RH... 为了筛选兔出血症病毒(RHDV)衣壳蛋白(VP60)的特异性单抗,并进一步分析单抗识别表位的分布情况,将重组杆状病毒r Ac V-Bac-VP60接种Sf9昆虫细胞,收获细胞培养物,电镜观察显示重组VP60蛋白获得有效表达,并可组装成病毒样粒子(VLPs)。将RHDV VLPs作为免疫原与等量弗氏佐剂乳化,免疫BALB/c小鼠,取脾细胞与SP2/0骨髓瘤细胞融合,经3次亚克隆后,获得11株能稳定分泌抗RHDV VLPs抗体的阳性杂交瘤细胞株。间接ELISA、IFA和Western Blot鉴定结果表明,这11株单克隆抗体均能够特异地识别RHDV VLPs和天然RHDV。11株单抗均为Ig G1,其中1D4和3F7的轻链为Lambda型,其余均为Kappa型。截短表达结果显示,单抗5A3针对RHDV VP60的NTA区,5F3针对RHDV VP60的S区,单抗1B8、1D4、3D11、3F7、4C2、4G2、5G2、5H3和6B2针对RHDV VP60的P区。研究为RHDV VLPs抗原表位的鉴定和RHDV结构功能的研究奠定了基础,同时为RHDV的检测和新型疫苗研究提供物质基础。 展开更多
关键词 RHDV vlpS 单克隆抗体 表位 初步定位
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铝佐剂对HBoV1 VP2 VLPs诱导小鼠免疫应答的影响 被引量:2
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作者 邓中华 段招军 +3 位作者 谢志萍 谢乐云 张兵 曹友德 《中国免疫学杂志》 CAS CSCD 北大核心 2016年第1期56-58,64,共4页
目的:探讨铝佐剂对HBoV1 VP2 VLPs诱导小鼠免疫应答的影响。方法:BABL/c小鼠随机分为VLPs实验组、明矾佐剂实验组、PBS对照组和明矾佐剂对照组。实验组小鼠分别采用HBoV1 VP2 VLPs和HBoV1 VP2 VLPs加明矾佐剂肌肉注射免疫,对照组小鼠同... 目的:探讨铝佐剂对HBoV1 VP2 VLPs诱导小鼠免疫应答的影响。方法:BABL/c小鼠随机分为VLPs实验组、明矾佐剂实验组、PBS对照组和明矾佐剂对照组。实验组小鼠分别采用HBoV1 VP2 VLPs和HBoV1 VP2 VLPs加明矾佐剂肌肉注射免疫,对照组小鼠同期注射等量明矾佐剂或PBS缓冲液;实验8周后ELISA检测两实验组特异性Ig G抗体效价和活性,ELIspot检测两实验组特异性细胞免疫反应强度,从细胞免疫和体液免疫强度探讨铝佐剂对HBoV1 VP2 VLPs诱导小鼠免疫应答的影响。结果:明矾佐剂降低HBoV1 VP2 VLPs诱导细胞免疫反应强度(P<0.001),增强HBoV1 VP2 VLPs诱导的血清Ig G效价(P<0.01)和Ig G活性(P<0.05)。结论:明矾佐剂使HBoV1 VP2 VLPs诱导的体液免疫反应增强而细胞免疫反应减弱。HBoV1 VP2 VLPs作为预防性疫苗使用时应添加明矾佐剂,作为治疗性疫苗使用时应不加明矾佐剂。 展开更多
关键词 铝佐剂 人博卡病毒1(HBoV1) 病毒蛋白2(VP2) 病毒样颗粒(vlps)
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Her2/ECD-sf162/TM嵌合VLPs的制备及抗肿瘤免疫效果研究 被引量:1
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作者 龙敏 董柯 +3 位作者 王希 林芳 刘冲 张惠中 《现代肿瘤医学》 CAS 2016年第21期3355-3359,共5页
目的:成功制备Her2胞外段基因与猴免疫缺陷病毒(simian immunodeficiency virus,SIV)包膜蛋白sf162跨膜区基因融合的Her2/ECD-sf162/TM病毒样颗粒(VLPs),并在小鼠体内进行初步的抗肿瘤免疫效果研究。方法:利用前期构建好的Her2/neu与SIV... 目的:成功制备Her2胞外段基因与猴免疫缺陷病毒(simian immunodeficiency virus,SIV)包膜蛋白sf162跨膜区基因融合的Her2/ECD-sf162/TM病毒样颗粒(VLPs),并在小鼠体内进行初步的抗肿瘤免疫效果研究。方法:利用前期构建好的Her2/neu与SIV-gag嵌合的表达载体Her2/ECD-sf162/TM,制备Her2/neu与SIV-gag嵌合型VLPs疫苗,并用该疫苗免疫小鼠。结果:VLPs可成功激发小鼠体内免疫应答反应,产生血清抗VLPs的抗体;VLP免疫后接种Her2/neu+小鼠乳腺癌细胞EMT6,结果显示该疫苗可有效抑制肿瘤生长;同时,VLP对荷瘤鼠治疗结果也显示,该疫苗可在一定程度上抑制肿瘤生长。结论:VLPs疫苗具有良好的免疫原性,且免疫后对肿瘤攻击具有保护作用。 展开更多
关键词 HER2/NEU 肿瘤疫苗 vlpS 免疫
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生长温度对Si基Ge量子点VLP-CVD自组织生长的影响 被引量:2
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作者 吴军 顾书林 +6 位作者 施毅 江宁 朱顺明 郑有炓 王牧 刘晓勇 闵乃本 《高技术通讯》 EI CAS CSCD 2000年第4期34-37,共4页
对利用超低压化学气相淀积 (VLP CVD)技术在Si上自组织生长Ge量子点的特征进行了研究 ,发现生长温度对Ge量子点尺寸分布和密度的影响不同于分子束外延 (MBE)的结果 ,这种现象与VLP CVD表面控制反应模式有关。实验表明 。
关键词 GE量子点 化学气相淀积 自组织生长
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汉滩病毒VLP的构建及其生物学特性的研究 被引量:1
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作者 应旗康 张晓晓 +4 位作者 王芳 冯伟 张尧 吴兴安 刘梓愉 《科学技术与工程》 北大核心 2015年第10期159-162,共4页
汉滩病毒是一种单负链RNA病毒,在我国主要引起以发热、出血、急性肾功能损害和免疫功能紊乱为主要特征的肾综合征出血热(HFRS),临床治疗尚无特效治疗药物,主要依靠灭活疫苗进行预防,但其诱导机体产生病毒中和抗体滴度较低,诱导细胞免疫... 汉滩病毒是一种单负链RNA病毒,在我国主要引起以发热、出血、急性肾功能损害和免疫功能紊乱为主要特征的肾综合征出血热(HFRS),临床治疗尚无特效治疗药物,主要依靠灭活疫苗进行预防,但其诱导机体产生病毒中和抗体滴度较低,诱导细胞免疫反应能力差。病毒样颗粒(virus like particles,VLP)具有病毒天然蛋白成分和构象,但不含病毒核酸,是理想的候选疫苗。将表达汉滩病毒包膜糖蛋白Gn和Gc的M片段与含有表达汉滩病毒核蛋白的S片段的载体在哺乳动物细胞中共表达,包装出汉滩病毒VLP,对包装出的VLP进行初步纯化和生物学特性的鉴定。 展开更多
关键词 汉滩病毒 病毒免疫 vlp 疫苗
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H3N8亚型马流感病毒VLPs的构建及其生物学特性分析 被引量:3
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作者 刘春国 王伟 +5 位作者 刘飞 刘彦云 王丹 吕让 刘明 相文华 《中国兽医科学》 CAS CSCD 北大核心 2014年第3期240-244,共5页
为了构建含H3N8亚型马流感病毒HA蛋白和M1蛋白的病毒样颗粒疫苗,把A/equine/Xinjiang/3/2007(H3N8)的HA基因和M1基因克隆到杆状病毒穿梭载体pFastBac Dual中,将得到的重组穿梭质粒pFBD-XJ3HA-M1转化至DH10Bac感受态细胞,与杆状病毒骨架... 为了构建含H3N8亚型马流感病毒HA蛋白和M1蛋白的病毒样颗粒疫苗,把A/equine/Xinjiang/3/2007(H3N8)的HA基因和M1基因克隆到杆状病毒穿梭载体pFastBac Dual中,将得到的重组穿梭质粒pFBD-XJ3HA-M1转化至DH10Bac感受态细胞,与杆状病毒骨架质粒Bacmid进行重组从而获得重组杆状病毒转座子rBac-XJ3HA-M1,然后将其转染Sf9昆虫细胞,包装重组杆状病毒rBV-XJ3HA-M1。通过PCR鉴定、细胞免疫组织化学试验、Western-blot分析以及血凝试验证明,HA蛋白和M1蛋白在昆虫细胞中能够有效表达,且表达产物具有良好的反应活性,表达的HA蛋白具有血凝活性。电镜观察发现,HA蛋白和M1蛋白能够稳定形成病毒样颗粒。上述研究结果为研制马流感亚单位疫苗提供了技术储备,也为马流感病毒蛋白的功能研究奠定了基础。 展开更多
关键词 马流感病毒 H3N8亚型 HA基因 M1基因 杆状病毒双表达 病毒样颗粒
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