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Anti-glial fibrillary acidic protein antibody and anti-aquaporin-4 antibody double-positive neuromyelitis optica spectrum disorder:A case report
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作者 Ting-Yu Jin Bing-Tong Lin +3 位作者 Li-Jv Dai Xia Lu Han Gao Jin Hu 《World Journal of Clinical Cases》 SCIE 2023年第34期8192-8199,共8页
BACKGROUND A case of neuromyelitis optica spectrum disorder(NMOSD)with positive cerebrospinal fluid(CSF)anti-aquaporin-4 antibody(AQP4-IgG)and anti-glial fibrillary acidic protein IgG(GFAP-IgG)at the time of relapse w... BACKGROUND A case of neuromyelitis optica spectrum disorder(NMOSD)with positive cerebrospinal fluid(CSF)anti-aquaporin-4 antibody(AQP4-IgG)and anti-glial fibrillary acidic protein IgG(GFAP-IgG)at the time of relapse was reported.The exact roles of GFAP-IgG in NMOSD are not fully understood and are the subject of ongoing research.This study revealed the possible connection between GFAPIgG and the occurrence or development of diseases.CASE SUMMARY A 19-year-old woman was admitted to the hospital due to a constellation of symptoms,including dizziness,nausea,and vomiting that commenced 1 year prior,reoccurred 2 mo ago,and were accompanied by visual blurring that also began 2 mo ago.Additionally,she presented with slurred speech and ptosis,both of which emerged 1 mo ago.Notably,her symptoms deteriorated 10 d prior to admission,leading to the onset of arm and leg weakness.During hospitalization,magnetic resonance imaging showed high T2-fluid attenuated inversion recovery signals,and slightly high and equal diffusion-weighted imaging signals.The serum antibody of AQP4-IgG tested positive at a dilution of 1:100.CSF antibody testing showed positive results for GFAP-IgG at a dilution of 1:10 and AQP4-IgG at a dilution of 1:32.Based on these findings,the patient was diagnosed with NMOSD.She received intravenous methylprednisolone at a daily dose of 500 mg for 5 d,followed by a tapering-off period.Afterward,the rate of reduction was gradually slowed down and the timely use of immunosuppressants was implemented.CONCLUSION The CFS was slightly GFAP-IgG-positive during the relapse period,which can aid in the diagnosis and treatment of the disease. 展开更多
关键词 Anti-glial fibrillary acidic protein antibody Neuromyelitis optica spectrum disorder Anti-aquaporin-4 antibody Cerebrospinal fluid Case report
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Fine mapping and cloning of the sterility gene Bra2Ms in nonheading Chinese cabbage(Brassica rapa ssp.chinensis)
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作者 Liping Song Xia Li +8 位作者 Liguang Tang Chuying Yu Bincai Wang Changbin Gao Yanfeng Xie Xueli Zhang Junliang Wang Chufa Lin Aihua Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1195-1204,共10页
The application of a male-sterile line is an ideal approach for hybrid seed production in non-heading Chinese cabbage(Brassica rapa ssp.chinensis).However,the molecular mechanisms underlying male sterility in B.rapa a... The application of a male-sterile line is an ideal approach for hybrid seed production in non-heading Chinese cabbage(Brassica rapa ssp.chinensis).However,the molecular mechanisms underlying male sterility in B.rapa are still largely unclear.We previously obtained the natural male sterile line WS24-3 of non-heading Chinese cabbage and located the male sterile locus,Bra2Ms,on the A2 chromosome.Cytological observations revealed that the male sterility of WS24-3 resulted from disruption of the meiosis process during pollen formation.Fine mapping of Bra2Ms delimited the locus within a physical distance of about 129 kb on the A2 chromosome of B.rapa.The Bra039753 gene encodes a plant homeodomain(PHD)-finger protein and is considered a potential candidate gene for Bra2Ms.Bra039753 was significantly downregulated in sterile line WS24-3 compared to the fertile line at the meiotic anther stage.Sequence analysis of Bra039753 identified a 369 bp fragment insertion in the first exon in male sterile plants,which led to an amino acid insertion in the Bra039753 protein.In addition,the 369 bp fragment insertion was found to cosegregate with the male sterility trait.This study identified a novel locus related to male sterility in non-heading Chinese cabbage,and the molecular marker obtained in this study will be beneficial for the marker-assisted selection of excellent sterile lines in non-heading Chinese cabbage and other Brassica crops. 展开更多
关键词 non-heading Chinese cabbage male sterility Bra2Ms fine mapping PHD-finger protein
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Quantitative trait loci identification reveals zinc finger protein CONSTANS-LIKE 4 as the key candidate gene of stigma color in watermelon(Citrullus lanatus)
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作者 Shuang Pei Zexu Wu +4 位作者 Ziqiao Ji Zheng Liu Zicheng Zhu Feishi Luan Shi Liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2292-2305,共14页
Stigma color is a critical agronomic trait in watermelon that plays an important role in pollination.However,there are few reports on the regulation of stigma color in watermelon.In this study,a genetic analysis of th... Stigma color is a critical agronomic trait in watermelon that plays an important role in pollination.However,there are few reports on the regulation of stigma color in watermelon.In this study,a genetic analysis of the F2 population derived from ZXG1553(P1,with orange stigma)and W1-17(P2,with yellow stigma)indicated that stigma color is a quantitative trait and the orange stigma is recessive compared with the yellow stigma.Bulk segregant analysis sequencing(BSA-seq)revealed a 3.75 Mb segment on chromosome 6 that is related to stigma color.Also,a major stable effective QTL Clqsc6.1(QTL stigma color)was detected in two years between cleaved amplified polymorphic sequencing(CAPS)markers Chr06_8338913 and Chr06_9344593 spanning a~1.01 Mb interval that harbors 51 annotated genes.Cla97C06G117020(annotated as zinc finger protein CONSTANS-LIKE 4)was identified as the best candidate gene for the stigma color trait through RNA-seq,quantitative real-time PCR(qRT-PCR),and gene structure alignment analysis among the natural watermelon panel.The expression level of Cla97C06G117020 in the orange stigma accession was lower than in the yellow stigma accessions with a significant difference.A nonsynonymous SNP site of the Cla97C06G117020 coding region that causes amino acid variation was related to the stigma color variation among nine watermelon accessions according to their re-sequencing data.Stigma color formation is often related to carotenoids,and we also found that the expression trend of ClCHYB(annotated asβ-carotene hydroxylase)in the carotenoid metabolic pathway was consistent with Cla97C06G117020,and it was expressed in low amounts in the orange stigma accession.These data indicated that Cla97C06G117020 and ClCHYB may interact to form the stigma color.This study provides a theoretical basis for gene fine mapping and mechanisms for the regulation of stigma color in watermelon. 展开更多
关键词 WATERMELON stigma color gene mapping zinc finger protein CONSTANS-LIKE 4
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Combining QTL Mapping and Multi-Omics Identify Candidate Genes for Nutritional Quality Traits during Grain Filling Stage in Maize
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作者 Pengcheng Li Tianze Zhu +7 位作者 Yunyun Wang Shuangyi Yin Xinjie Zhu Minggang Ji Wenye Rui Houmiao Wang Zefeng Yang Chenwu Xu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第7期1441-1453,共13页
The nutritional composition and overall quality of maize kernels are largely determined by the key chemical com-ponents:protein,oil,and starch.Nevertheless,the genetic basis underlying these nutritional quality traits... The nutritional composition and overall quality of maize kernels are largely determined by the key chemical com-ponents:protein,oil,and starch.Nevertheless,the genetic basis underlying these nutritional quality traits during grainfilling remains poorly understood.In this study,the concentrations of protein,oil,and starch were studied in 204 recombinant inbred lines resulting from a cross between DH1M and T877 at four different stages post-pollination.All the traits exhibited considerable phenotypic variation.During the grain-filling stage,the levels of protein and starch content generally increased,whereas oil content decreased,with significant changes observed between 30 and 40 days after pollination.Quantitative trait locus(QTL)mapping was conducted and a total of 32 QTLs,comprising 14,12,and 6 QTLs for grain protein,oil,and starch content were detected,respectively.Few QTLs were consistently detectable across different time points.By integrating QTL analysis,glo-bal gene expression profiling,and comparative genomics,we identified 157,86,and 54 differentially expressed genes harboring nonsynonymous substitutions between the parental lines for grain protein,oil,and starch con-tent,respectively.Subsequent gene function annotation prioritized 15 candidate genes potentially involved in reg-ulating grain quality traits,including those encoding transcription factors(NAC,MADS-box,bZIP,and MYB),cell wall invertase,cellulose-synthase-like protein,cell division cycle protein,trehalase,auxin-responsive factor,and phloem protein 2-A13.Our study offers significant insights into the genetic architecture of maize kernel nutritional quality and identifies promising QTLs and candidate genes,which are crucial for the genetic enhance-ment of these traits in maize breeding programs. 展开更多
关键词 MAIZE protein oil STARCH QTL mapping candidate genes
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Effects of Mapping Methods on Accuracy of Protein Coding Regions Prediction
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作者 马玉韬 张成 +2 位作者 杨泽林 李琦 杨婷 《Agricultural Science & Technology》 CAS 2011年第12期1802-1806,1860,共6页
[Objective] To discuss the effects of major mapping methods for DNA sequence on the accuracy of protein coding regions prediction,and to find out the effective mapping methods.[Method] By taking Approximate Correlatio... [Objective] To discuss the effects of major mapping methods for DNA sequence on the accuracy of protein coding regions prediction,and to find out the effective mapping methods.[Method] By taking Approximate Correlation(AC) as the full measure of the prediction accuracy at nucleotide level,the windowed narrow pass-band filter(WNPBF) based prediction algorithm was applied to study the effects of different mapping methods on prediction accuracy.[Result] In DNA data sets ALLSEQ and HMR195,the Voss and Z-Curve methods are proved to be more effective mapping methods than paired numeric(PN),Electron-ion Interaction Potential(EIIP) and complex number methods.[Conclusion] This study lays the foundation to verify the effectiveness of new mapping methods by using the predicted AC value,and it is meaningful to reveal DNA structure by using bioinformatics methods. 展开更多
关键词 Prediction accuracy protein coding regions mapping method Windowed Narrow pass-band filter
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In situ Detection of Amide A Bands of Proteins in Water by Raman Ratio Spectrum 被引量:1
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作者 汤城骞 林珂 +1 位作者 周晓国 刘世林 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第1期129-134,I0002,共7页
The amide A band of protein is sensitive to the hydrogen bands of amide groups of proteins. However, it is hard to distinguish the amide A band of aqueous protein in situ directly, since it overlaps with O-H stretchin... The amide A band of protein is sensitive to the hydrogen bands of amide groups of proteins. However, it is hard to distinguish the amide A band of aqueous protein in situ directly, since it overlaps with O-H stretching vibration of water. In this work, we presented a new analytical method of Raman ratio spectrum, which can extract the amide A band of proteins in water. To obtain the Raman ratio spectrum, the Raman spectrum of aqueous protein was divided by that of pure water. A mathematical simulation was employed to examine whether Raman ratio spectrum is effective. Two kinds of protein, lysozyme and (^-chymotrypsin were employed. The amide A bands of them in water were extracted from Raman ratio spectra. Additionally, the process of thermal denaturation of lysozyme was detected from Raman ratio spectrum. These results demonstrated the Raman ratio spectra could be employed to study the amide A modes of proteins in water. 展开更多
关键词 Raman ratio spectrum. Amide A band. In situ protein WATER
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Temperature-Dependence of the Amide-Ⅰ Frequency Map for Peptides and Proteins
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作者 韩晨 王建平 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第5期529-537,I0003,共10页
In our recent work [Phys. Chem. Chem. Phys. 11, 9149 (2009)], a molecular-mechanics force field-based amidc-Ⅰ vibration frequency map (MM-map) for peptides and proteins was constructed. In this work, the temperat... In our recent work [Phys. Chem. Chem. Phys. 11, 9149 (2009)], a molecular-mechanics force field-based amidc-Ⅰ vibration frequency map (MM-map) for peptides and proteins was constructed. In this work, the temperature dependence of the MM-map is examined based on high-temperature molecular dynamics simulations and infrared (IR) experiments. It is shown that the 298-K map works for up to 500-K molecular dynamics trajectories, which reasonably reproduces the 88 ℃ experimental IR results. Linear IR spectra are also simulated for two tripeptides containing natural and unnatural amino acid residues, and the results are in reasonable agreement with experiment. The results suggest the MM-map can be used to obtain the temperature-dependent amide-Ⅰ local mode frequencies and their distributions for peptide oligomers, which is useful in particular for understanding the IR signatures of the thermally unfolded species. 展开更多
关键词 Amide-Ⅰ Frequency map Infrared spectrum Molecular dynamics simulation
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THE DIFFERENCE IN EEG THETA WAVES BETWEEN CONCENTRATIVE AND NON-CONCENTRATIVE QIGONG STATES -A Power Spectrum and Topographic Mapping Study 被引量:1
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作者 潘卫星 张露芬 夏勇 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1994年第3期212-218,共7页
The differences in EEG theta waves between concentrative and non--concentrative Qigong stateswere studied by means of power spectrum analysis and EEG mapping. The adult subjects in-cluded 20 practitioners of concentra... The differences in EEG theta waves between concentrative and non--concentrative Qigong stateswere studied by means of power spectrum analysis and EEG mapping. The adult subjects in-cluded 20 practitioners of concentrative Qigong, 30 Practitioners of non--concenthetive Qigongand 23 control subjects. The results showed frontal mid--line theta rhythm was related toconcentrative Qigong state. As the theta rhythm has been suggested to be one of the normal EEGPatterns occurring in mental concentration,it is concluded that the theta rhythm is an indicatorof mental concentration during Qigong state. This finding clarifies the implication of the thetarhythms appearing in Qigong and other meditation. 展开更多
关键词 RHYTHM THETA appearing mapping implication spectrum FRONTAL finding thinking HEMISPHERE
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Protein-protein interaction map is a key gateway into liver regeneration 被引量:3
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作者 Chao Xie Run-Zhi Zhu +6 位作者 Yun-Sheng Yuan Hong-Lin He Yan Yu Chao Xie Qiu-Shi Huang Jin Gao Wei Han 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第28期3491-3498,共8页
Recent studies indicate that the process of liver regeneration involves multiple signaling pathways and a variety of genes,cytokines and growth factors. Protein-protein interactions(PPIs)play a role in nearly all even... Recent studies indicate that the process of liver regeneration involves multiple signaling pathways and a variety of genes,cytokines and growth factors. Protein-protein interactions(PPIs)play a role in nearly all events that take place within the cell and PPI maps should be helpful in further understanding the process of liver regeneration.In this review,we discuss recent progress in understanding the PPIs that occur during liver regeneration especially those in the transforming growth factorβsignaling pathways.We believe the use of large-scale PPI maps for integrating the information already known about the liver regeneration is a useful approach in understanding liver regeneration from the standpoint of systems biology. 展开更多
关键词 Liver regeneration protein-protein interaction protein-protein interaction maps Transforming growth factorβ
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Protein structural classification and family identification by multifractal analysis and wavelet spectrum
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作者 朱少茗 喻祖国 Ahn Vo 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期194-208,共15页
Family identification is helpful for predicting protein functions. It has been known from the literature that longer sequences of base pairs or amino acids are required to study patterns in biological sequences. Since... Family identification is helpful for predicting protein functions. It has been known from the literature that longer sequences of base pairs or amino acids are required to study patterns in biological sequences. Since most protein sequences are relatively short, we randomly concatenate or link the protein sequences from the same family or superfamily together to form longer protein sequences. The 6-letter model, 12-letter model, 20-letter model, the revised Schneider and Wrede scale hydrophobicity, solvent accessibility and stochastic standard state accessibility are used to convert linked protein sequences into numerical sequences. Then multifractal analyses and wavelet analysis are performed on these numerical sequences. The parameters from these analyses can be used to construct parameter spaces where each linked protein is represented by a point. The four classes of proteins, namely the α/β, α+β and α/β classes, are then distinguished in these parameter spaces. The Fisher linear discriminant algorithm is used to assess the discriminant accuracy. Numerical results indicate that the discriminant accuracies are satisfactory in separating these classes. We find that the linked proteins from the same family or superfamily tend to group together and can be separated from other linked proteins. The methods are helpful for identifying the family of an unknown protein. 展开更多
关键词 protein family multifractal analysis wavelet spectrum
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Variations on conserved signaling pathways in biocontrol and development: G protein and MAPK genes of Trichoderma. atroviride and T. virens 被引量:1
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作者 Benjiamin A Horwitz 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2004年第4期444-444,共1页
Filamentous fungi employ conserved eukaryotic signaling pathway to detect and respond to environmental signals, including the presence of the host. Genetic experiment in which a particular signaling protein is lost, o... Filamentous fungi employ conserved eukaryotic signaling pathway to detect and respond to environmental signals, including the presence of the host. Genetic experiment in which a particular signaling protein is lost, or its activity enhanced, have defined some of the function of heterotrimeric G proteins and MAP kinases in development and virulence. A hallmark of these studies is that orthologs in different species may have different functions. Antagonistic fungal-fungal interactions form the basis for biological control of plant disease. These interactions may employ novel modes of regulation by conserved signaling elements. Tag1, a G protein α subunit of Trichoderma. atroviride belonging to fungal Gi class, is involved in repression of sporulation and hyphal coiling(1). Deletion of ortholog of this gene, TgaA, in Trichoderma (Gliocladium) virens, however, did not affect sporulation and growth, yet tgaA mutants are unable to parasitize S. rolfsii sclerotia(2). Mutation of a second G α subunit gene is now under study. TmkA, a MAPK gene of T. virens, is involved in biocontrol properties and repression of conidiation(3). Using suppression-subtraction hybridization and other approaches, we are beginning to identify additional elements of the signaling cascades and their downsteam targets. The role of G protein and MAPK genes are sometimes specific to a particular host fungus or to parasitism of mycelia or sclerotia(2,3). Also of relevance to biocontrol, signal transduction pathway provide a means to alter the balance between sporulation, mycelial growth and hyphal coiling. 展开更多
关键词 木霉属 真菌 基因 变异 信号通道 G蛋白 生物防治
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Fazari’s Sign in Ultrasound Scan of Morbid Adherent Placenta/Placenta Accreta Spectrum (MAP/PAS) and Fazari’s Triad during (MAP/PAS) Surgery
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作者 Atif Bashir Eltayeb Fazari Zeinabsadat Tabatabaei Hakim 《Open Journal of Obstetrics and Gynecology》 2020年第4期599-603,共5页
Morbid Adherent Placenta (MAP)/Placenta Accreta Spectrum (PAS) is a serious diagnosis which has a risk of complications. Ultrasound scan helps in early diagnosis and has great value in further confirmation and follow ... Morbid Adherent Placenta (MAP)/Placenta Accreta Spectrum (PAS) is a serious diagnosis which has a risk of complications. Ultrasound scan helps in early diagnosis and has great value in further confirmation and follow up. Observed new clinical sign and associated clinical triad are discussed here. 展开更多
关键词 MORBID Adherent PLACENTA (map)/Placenta Accreta spectrum (PAS) Ultrasound Scan Stair Step SIGN Fazari’s TRIAD
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全面供光策略调控废水培养光合细菌产单细胞蛋白
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作者 王晓丹 卢海凤 +5 位作者 张光明 司哺春 卞含笑 唐帅 蒋伟忠 李保明 《农业工程学报》 EI CAS CSCD 北大核心 2024年第11期227-237,共11页
为拓展蛋白质来源,缓解中国饲料蛋白资源短缺现状,该研究通过供光策略调控强化了沼泽红假单胞菌(R.palustris)从废水中回收菌体资源及单细胞蛋白(single cell protein, SCP)的效果,并解析了不同供光策略下物质合成与污染物降解之间的相... 为拓展蛋白质来源,缓解中国饲料蛋白资源短缺现状,该研究通过供光策略调控强化了沼泽红假单胞菌(R.palustris)从废水中回收菌体资源及单细胞蛋白(single cell protein, SCP)的效果,并解析了不同供光策略下物质合成与污染物降解之间的相关性。结果表明:在白炽灯、120μmol/(m^(2)·s)的光强及18 h光/6 h暗(L/D)的光周期条件下菌体的生物量及日产量可达(1 140.56±19.72) mg/L及(0.32±0.02) g/(L·d),相较于24 L/0 D、 3 L/21 D及9 L/15 D组分别提高了17.06%~93.21%、54.43%~299.93%(P<0.05);在白炽灯、120 μmol/(m^(2)·s)的光强及3 h光/21 h暗的光周期条件下,菌体的蛋白质质量分数最高,为67.47%,相较于其他所有试验组提高了21.96%~44.54%(P<0.05)。化学需氧量(chemical oxygen demand, COD)和氨氮(ammonia nitrogen, NH_(4)^(+)-N)去除率在白炽灯、120 μmol/(m^(2)·s)的光强及18 h光/6 h暗的光周期条件下可达72.03%~78.40%。相关性分析表明,光强、光质分别与蛋白质含量及浓度呈显著负相关;而光周期与蛋白质浓度呈显著正相关,因此,光周期是R. palustris从废水体系中提升SCP产量的有效调控方法。该研究为提高废水体系中光合细菌合成SCP提供了新的方法与思路。 展开更多
关键词 光质 光强 光周期 光合细菌 单细胞蛋白 污染物降解
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小样本学习驱动的无线频谱状态感知
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作者 申滨 李月 +1 位作者 王欣 王紫昕 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第4期1231-1239,共9页
无线频谱状态感知是实现无线频谱资源高效利用及各种用频系统和谐共存的先决条件之一。针对复杂无线传播环境下获取的频谱观测往往存在数据稀疏性、数据类别分布不稳定、标记数据严重不足的情况,该文提出基于插值和小样本学习(FSL)分类... 无线频谱状态感知是实现无线频谱资源高效利用及各种用频系统和谐共存的先决条件之一。针对复杂无线传播环境下获取的频谱观测往往存在数据稀疏性、数据类别分布不稳定、标记数据严重不足的情况,该文提出基于插值和小样本学习(FSL)分类的无线频谱状态感知方法。首先,对捕获的稀疏频谱观测数据插值,构建频谱状态地图,作为频谱状态分类器的输入数据。其次,针对频谱数据类别分布不稳定、数据量严重不足的问题,基于小样本学习方法,利用嵌入模块和度量模块协同工作,以实现快速精确的频谱状态分类。具体地,利用嵌入模块将频谱数据映射到嵌入空间,提取频谱数据中的隐含特征;在度量模块的设计中,分别提出基于原型和基于样例的两种类别表示方式,通过计算待分类样本与类别之间的相似度判断待分类样本类别。最后,为了确保分类模型克服测试样本数量少导致过拟合问题,设置A-way B-shot任务训练模型。仿真结果表明,与传统机器学习方法相比,本文模型可以在低信噪比条件下进行精准分类;同时,在测试集样本数很少的情况下,或者在测试集中出现在训练集从未见到的新类时,所训练的模型也可以精准快速判别无线频谱的场景类别。 展开更多
关键词 频谱状态感知 频谱状态地图 插值 小样本学习
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复杂环境下电磁目标信号认知处理架构与应用研究
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作者 张伟 李想 +3 位作者 翟志凯 张谦 邵怀宗 孟建 《电子科技大学学报》 EI CAS CSCD 北大核心 2024年第1期40-49,共10页
针对现代电磁频谱设备或终端具有网络化、捷变性、多功能、自适应、种类复杂多样和使用环境复杂多变等特性给认知电磁频谱战系统的信号分析与处理带来的巨大挑战的问题,提出了一种结合人工智能、适合复杂电磁环境下电磁目标信号认知处... 针对现代电磁频谱设备或终端具有网络化、捷变性、多功能、自适应、种类复杂多样和使用环境复杂多变等特性给认知电磁频谱战系统的信号分析与处理带来的巨大挑战的问题,提出了一种结合人工智能、适合复杂电磁环境下电磁目标信号认知处理与分析的架构。在该架构下电磁目标信号分析与处理被分为目标信号参数估计、目标信号类型分类、辐射源个体识别和目标信号的特征建库与知识图谱[1-3]的构建等4个层次,可以很好适应闭集和开集电磁目标信号的分析与处理;此外,在此架构下提出了未知辐射源辨识、跨模态辐射源智能识别和电磁辐射源的个体识别的算法框架,在实测数据集上的验证实验表明,该算法在闭集和开集电磁信号分析中有效可行。 展开更多
关键词 电磁频谱战 认知处理架构 电磁目标知识图谱与推理 辐射源个体识别
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无人机高光谱岩性和矿物识别技术研究
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作者 刘洪成 叶发旺 +3 位作者 韩晓青 谭宏婕 鲁纳川 张川 《世界核地质科学》 CAS 2024年第3期560-572,共13页
无人机高光谱遥感技术以其高空间分辨率和高光谱分辨率的技术优势,在大比例尺区域地质填图领域可以发挥重要作用。利用无人机搭载全谱段高光谱成像仪(HD_SAVI)获取0.2 m高空间分辨率影像数据,采用经验线性法对所获取数据进行光谱重建,... 无人机高光谱遥感技术以其高空间分辨率和高光谱分辨率的技术优势,在大比例尺区域地质填图领域可以发挥重要作用。利用无人机搭载全谱段高光谱成像仪(HD_SAVI)获取0.2 m高空间分辨率影像数据,采用经验线性法对所获取数据进行光谱重建,重建后无人机高光谱影像光谱曲线与地面实测光谱曲线谱形基本一致,典型特征吸收峰位置偏差均在1个像元以内。采集岩性样本构建岩性知识库,利用深度学习算法基于无人机高光谱影像数据开展岩性识别;岩性识别结果与大比例尺地质图对比,岩性空间分布基本一致,地质体边界准确且较清晰。参考典型矿物光谱库进行矿物识别。与同一地区CASI/SASI航空高光谱数据地质填图结果进行对比分析,结果表明:两者提取的矿物在空间分布上具有较高的一致性,但无人机低空高光谱影像空间分辨率较高,识别出的矿物种类更加丰富。无人机高光谱遥感技术可以满足无人区、交通不便地区地质勘查,以及重点区或矿区外围等地区大比例尺地质填图的需要。 展开更多
关键词 全谱段高光谱成像仪 经验线性法 岩性样本 深度学习 大比例尺地质填图
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基于无线环境地图的星地智能频谱共享方法
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作者 张曦木 贾敏 +1 位作者 顾学迈 郭庆 《指挥与控制学报》 CSCD 北大核心 2024年第1期32-37,共6页
卫星和地面组件共享同一频段可以有效缓解频谱稀缺问题,提升频谱利用率,星地频谱共享将在未来的无线系统中发挥至关重要的作用。相较于传统的七色复用星地频谱共享方案均匀地分配点波束带宽,通过波束预测能够基于点波束流量需求的变化... 卫星和地面组件共享同一频段可以有效缓解频谱稀缺问题,提升频谱利用率,星地频谱共享将在未来的无线系统中发挥至关重要的作用。相较于传统的七色复用星地频谱共享方案均匀地分配点波束带宽,通过波束预测能够基于点波束流量需求的变化合理分配带宽,而频谱预测能够有效降低碰撞概率,从而提升网络频谱效率。提出一种基于无线环境地图的星地智能频谱共享方法,该方法联合波束预测和频谱预测,构建无线环境地图并基于无线环境地图进行频谱分配。仿真结果表明,该方法可有效提升频谱利用率,降低网络阻塞率和用户等待时间。 展开更多
关键词 星地频谱共享 无线环境地图 深度学习 频谱利用率
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MAP激酶家族在淀粉样β蛋白片段25~35引起的大鼠海马炎症反应及细胞凋亡中的作用(英文) 被引量:11
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作者 金英 范莹 +3 位作者 闫恩志 宗志红 包翠芬 李智 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2005年第3期161-168,共8页
目的 研究淀粉样β蛋白片段2 5~35(Aβ2 5~35)引起的大鼠海马炎症反应、细胞凋亡机制及抗炎药物布洛芬的保护作用。方法 大鼠灌胃给予布洛芬7.5mg·kg- 1,连续应用3周,脑室内单次注射Aβ2 5~35(10 μL ,1mmol·L- 1) ,注... 目的 研究淀粉样β蛋白片段2 5~35(Aβ2 5~35)引起的大鼠海马炎症反应、细胞凋亡机制及抗炎药物布洛芬的保护作用。方法 大鼠灌胃给予布洛芬7.5mg·kg- 1,连续应用3周,脑室内单次注射Aβ2 5~35(10 μL ,1mmol·L- 1) ,注射后继续应用布洛芬1周后,取脑,进行尼氏染色和胶质原纤维酸性蛋白(GFAP)免疫细胞化学染色,研究海马CA1区锥体神经元形态学改变和星形胶质细胞激活。Western印迹观察白细胞介素 1β(IL 1β) ,胞外信号调节激酶1/ 2 (ERK1/ 2 ) ,有丝分裂原活化蛋白激酶p38(p38MAPK) ,蛋白激酶C(PKC)和半胱氨酸天冬氨酸蛋白酶 3(caspase 3)蛋白表达。RT PCR分析IL 1βmRNA表达水平。结果 脑室内注射Aβ2 5~35可引起海马CA1区星形胶质细胞激活和浸润,IL 1β蛋白表达和IL 1βmRNA表达水平明显增加,这种炎症反应伴有海马CA1区锥体神经元损伤。另外,Aβ2 5~35也能引起磷酸化的p38MAPK蛋白表达较对照组明显增加,从对照组0 .16 7±0 .0 91增加到0 .4 97±0 .0 5 9(P <0 .0 1,n =4 )。使磷酸化的ERK1/ 2蛋白表达下调,ERK1的表达从对照组0 .14 6±0 .0 10下降到0 (P <0 .0 1,n =4 )。ERK2表达从对照组的0 .4 12±0 .0 5 4下降到0 .131±0 .0 38(P <0 .0 1,n =4 )。这些改变伴随有caspase 展开更多
关键词 淀粉样Β-蛋白 炎症 map激酶信号系统 p38 map激酶 半胱氨酸天冬氨酸蛋白酶 细胞凋亡
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代谢综合征大鼠肥胖特征及ERK1/2和p38MAPK的作用研究 被引量:10
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作者 张雅萍 祝之明 +5 位作者 闫振成 钟健 王利娟 曹廷兵 聂海 杨华 《解放军医学杂志》 CAS CSCD 北大核心 2006年第8期794-797,共4页
目的探讨ERK1/2和p38MAPK在脂肪组织生长中的作用。方法Wistar雄性大鼠20只,随机均分为代谢综合征组和正常对照组,观察代谢综合征大鼠的代谢指标及体重、内脏脂肪含量、脂肪细胞大小和组织病理学改变,Westernblot法检测ERK1/2及p38MAPK... 目的探讨ERK1/2和p38MAPK在脂肪组织生长中的作用。方法Wistar雄性大鼠20只,随机均分为代谢综合征组和正常对照组,观察代谢综合征大鼠的代谢指标及体重、内脏脂肪含量、脂肪细胞大小和组织病理学改变,Westernblot法检测ERK1/2及p38MAPK蛋白在脂肪组织中的表达情况。结果代谢综合征大鼠血压、血浆游离脂肪酸、甘油三酯、空腹血糖及胰岛素均显著高于对照组(P<0·01),其体重、腹围、内脏脂肪含量、脂肪系数和各部位脂肪细胞大小亦比对照组显著增高(P<0·01),肝细胞存在脂肪变性。在棕色脂肪组织中ERK1/2蛋白的表达与对照组比较无显著性差异,皮下脂肪和内脏脂肪中ERK1/2蛋白的表达均显著高于对照组(P<0·01),而p38MAPK蛋白的表达在所有脂肪组织中均显著高于对照组(P<0·01)。结论代谢综合征大鼠肥胖特征为腹型肥胖,脂肪组织生长以肥大性增生为主,并存在脂质异位沉着(脂肪肝)。代谢综合征大鼠脂肪组织增生可能与ERK1/2和p38MAPK信号通路激活有关。 展开更多
关键词 代谢综合征 肥胖症 有丝分裂素激活蛋白激酶类 P38 map激酶
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MAPK信号通路在肝癌发生发展及治疗中的作用 被引量:18
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作者 次旦旺久 林坤 +2 位作者 卢再鸣 赵相轩 王晓明 《临床肝胆病杂志》 CAS 2016年第9期1810-1813,共4页
丝裂原活化蛋白激酶(MAPK)信号通路的异常活化与肝癌的发生、发展、转移密切相关。介绍了MAPK通路蛋白在肝癌中的表达及其在肝癌增殖、分化、转移中的作用,阐述了MAPK信号通路在肝癌治疗及预后评价中的价值。认为MAPK信号通路在肝癌的... 丝裂原活化蛋白激酶(MAPK)信号通路的异常活化与肝癌的发生、发展、转移密切相关。介绍了MAPK通路蛋白在肝癌中的表达及其在肝癌增殖、分化、转移中的作用,阐述了MAPK信号通路在肝癌治疗及预后评价中的价值。认为MAPK信号通路在肝癌的发生发展及治疗中发挥非常重要的作用,是肝癌治疗及预后评价的潜在分子靶点。 展开更多
关键词 肝肿瘤 丝裂原激活蛋白激酶类 map激酶信号系统 综述
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