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Identification of reservoir types in deep carbonates based on mixedkernel machine learning using geophysical logging data
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作者 Jin-Xiong Shi Xiang-Yuan Zhao +3 位作者 Lian-Bo Zeng Yun-Zhao Zhang Zheng-Ping Zhu Shao-Qun Dong 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1632-1648,共17页
Identification of reservoir types in deep carbonates has always been a great challenge due to complex logging responses caused by the heterogeneous scale and distribution of storage spaces.Traditional cross-plot analy... Identification of reservoir types in deep carbonates has always been a great challenge due to complex logging responses caused by the heterogeneous scale and distribution of storage spaces.Traditional cross-plot analysis and empirical formula methods for identifying reservoir types using geophysical logging data have high uncertainty and low efficiency,which cannot accurately reflect the nonlinear relationship between reservoir types and logging data.Recently,the kernel Fisher discriminant analysis(KFD),a kernel-based machine learning technique,attracts attention in many fields because of its strong nonlinear processing ability.However,the overall performance of KFD model may be limited as a single kernel function cannot simultaneously extrapolate and interpolate well,especially for highly complex data cases.To address this issue,in this study,a mixed kernel Fisher discriminant analysis(MKFD)model was established and applied to identify reservoir types of the deep Sinian carbonates in central Sichuan Basin,China.The MKFD model was trained and tested with 453 datasets from 7 coring wells,utilizing GR,CAL,DEN,AC,CNL and RT logs as input variables.The particle swarm optimization(PSO)was adopted for hyper-parameter optimization of MKFD model.To evaluate the model performance,prediction results of MKFD were compared with those of basic-kernel based KFD,RF and SVM models.Subsequently,the built MKFD model was applied in a blind well test,and a variable importance analysis was conducted.The comparison and blind test results demonstrated that MKFD outperformed traditional KFD,RF and SVM in the identification of reservoir types,which provided higher accuracy and stronger generalization.The MKFD can therefore be a reliable method for identifying reservoir types of deep carbonates. 展开更多
关键词 Reservoir type identification Geophysical logging data Kernel Fisher discriminantanalysis Mixedkernel function Deep carbonates
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FVID: Fishing Vessel Type Identification Based on VMS Trajectories 被引量:10
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作者 HUANG Haiguang HONG Feng +3 位作者 LIU Jing LIU Chao FENG Yuan GUO Zhongwen 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第2期403-412,共10页
Vessel Monitoring System(VMS) provides a new opportunity for quantified fishing research. Many approaches have been proposed to recognize fishing activities with VMS trajectories based on the types of fishing vessels.... Vessel Monitoring System(VMS) provides a new opportunity for quantified fishing research. Many approaches have been proposed to recognize fishing activities with VMS trajectories based on the types of fishing vessels. However, one research problem is still calling for solutions, how to identify the fishing vessel type based on only VMS trajectories. This problem is important because it requires the fishing vessel type as a preliminary to recognize fishing activities from VMS trajectories. This paper proposes fishing vessel type identification scheme(FVID) based only on VMS trajectories. FVID exploits feature engineering and machine learning schemes of XGBoost as its two key blocks and classifies fishing vessels into nine types. The dataset contains all the fishing vessel trajectories in the East China Sea in March 2017, including 10031 pre-registered fishing vessels and 1350 unregistered vessels of unknown types. In order to verify type identification accuracy, we first conduct a 4-fold cross-validation on the trajectories of registered fishing vessels. The classification accuracy is 95.42%. We then apply FVID to the unregistered fishing vessels to identify their types. After classifying the unregistered fishing vessel types, their fishing activities are further recognized based upon their types. At last, we calculate and compare the fishing density distribution in the East China Sea before and after applying the unregistered fishing vessels, confirming the importance of type identification of unregistered fishing vessels. 展开更多
关键词 VMS VESSEL type identification FISHING DENSITY TRAJECTORY analysis classification
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Isolation, Identification and Pathogenicity Analysis of Streptococcus suis Type 2 被引量:4
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作者 Zicheng MA Yan LI +6 位作者 Jinyuan GU Tao PENG Zhaohu LIU Hongyu WANG Fanliang MENG Fangkun WANG Sidang LIU 《Agricultural Biotechnology》 CAS 2019年第4期64-68,共5页
[Objectives]This study aimed to investigate the pathogenicity,growth characteristics and drug resistance of Streptococcus suis type 2.[Methods]Bacterial isolation and identification,biochemical experiments,determinati... [Objectives]This study aimed to investigate the pathogenicity,growth characteristics and drug resistance of Streptococcus suis type 2.[Methods]Bacterial isolation and identification,biochemical experiments,determination of growth curve and correlation curve between OD 600 values and viable counts,drug susceptibility tests,pathogenicity analysis,and histopathological observations were carried out.[Results]The Streptococcus strain isolated from infected pigs was identified as Streptococcus suis type 2,which was named TA01 strain.TA01 strain reached the growth peak at 6-8 h post-incubation,and viable counts gradually declined after 8 h of incubation.The correlation equation between OD 600 values and viable counts is y=24.659 x-1.076 1,R^2=0.996 7.TA01 strain was sensitive to penicillin,erythromycin,florfenicol and oxacillin,and resistant to ciprofloxacin,polymyxin B and clindamycin.According to the results of pathogenicity analysis,all the mice in 3.6×10^9 cfu/mouse group died within 48,and these dead mice exhibited acute pyaemia septica.Based on the Reed-Muench formula,it was calculated that LD 50 of TA01 strain was 1.137×10^8 cfu/mouse.Pathological examination showed obvious blue-stained bacteria clusters,accompanied by neutrophil infiltration.[Conclusions]TA01 strain was a virulent strain of Streptococcus suis type 2.Compared with Streptococcus strains which were isolated and reported in China,TA01 strain exhibited strong virulence and rapid proliferation. 展开更多
关键词 STREPTOCOCCUS SUIS type 2 ISOLATION and identification Growth curve Drug sensitivity test PATHOGENICITY LD 50 determination
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Identification, characteristic and phylogenetic analysis of type II DNA topoisomerase gene in Giardia lamblia 被引量:1
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作者 DeHE JianFanWEN +2 位作者 WanQunCHEN SiQiLU4 DeDongXIN 《Cell Research》 SCIE CAS CSCD 2005年第6期474-482,共9页
The genes encoding type II DNA topoisomerases were investigated in Giardia lamblia genome, and a type IIA gene,GlTop 2 was identified. It is a single copy gene with a 4476 bp long ORF without intron. The deduced amino... The genes encoding type II DNA topoisomerases were investigated in Giardia lamblia genome, and a type IIA gene,GlTop 2 was identified. It is a single copy gene with a 4476 bp long ORF without intron. The deduced amino acid sequence shows strong homology to eukaryotic DNA Top 2. However, some distortions were found, such as six insertions in the ATPase domain and the central domain, a -100 aa longer central domain; a ~200 aa shorter C-terminal domain containing rich charged residues. These features revealed by comparing with Top 2 of the host, human, might be helpful in exploiting drug selectivity for antigiardial therapy. Phylogenetic analysis of eukaryotic enzymes showed that kinetoplastids, plants, fungi, and animals were monophyletic groups, and the animal and fungi lineages shared a more recent common ancestor than either did with the plant lineage; microsporidia grouped with fungi. However, unlike many previous phylogenetic analyses, the ''amitochondriate'' G. lamblia was not the earliest branch but diverged after mitochondriate kinetoplastids in our trees. Both the finding of typical eukaryotic type IIA topoisomerase and the phylogenetic analysis suggest G, lamblia is not possibly as primitive as was regarded before and might diverge after the acquisition of mitochondria. This is consistent with the recent discovery of mitochondrial remnant organelles in G. lamblia. 展开更多
关键词 evolutionary position GlTop2 gene Giardia lamblia identification phylogenetic analysis type II DNAtopoisomerase.
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Isolation and Identification of Different Sources of Salmonella and Comparisons on the Drug Resistance Spectrum Types
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作者 CHEN Chao-xi XI Ge-ji TANG Cheng 《Animal Husbandry and Feed Science》 CAS 2013年第2期65-67,72,共4页
[ Objective] In order to make out differences between drug resistance spectrum types of different animal sources of Salmonella. [ Meth- otis] Selenite cystine broth, Salmonella- Shigella genus agar medium, CHROMagar S... [ Objective] In order to make out differences between drug resistance spectrum types of different animal sources of Salmonella. [ Meth- otis] Selenite cystine broth, Salmonella- Shigella genus agar medium, CHROMagar Salmonella chromogenic culture, Reveal Salmonella detection kit and molecular biology methods were used for isolation and identification of Salmonella from different animal feces samples. Antibacterialantimi- crobial susceptibility tests of 17 kinds of drugs such as enrofloxacin, apramycin and florfenicol were done on isolated strains with broth microdilution method, and test data was analysed with WHOnet 5.4 software. [ Results ] 699 feces samples from different animals were separated, and 53 strains of Salmonella were achieved with separation rate of 7.58%, among which those of yak, poultry, and pet sources were respectively 4.33%, 9.06% and 8.37%. [ Condusions] Separation rates and drug resistance spectrum types of different animal origin Salmonella varied greatly, among which separation rates and drug resistance spectrum types of yak source Salmonella were the lowest, there was little difference between separation rates of poultry and dog source Salmonella, however there were large differences on drug resistance spectrum types. 展开更多
关键词 SALMONELLA Isolation and identification Drug resistance spectrum type
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Isolation and Identification of Porcine Circovirus Type 2 in Taizhou
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作者 Guangfu GUO Aiping ZHU +3 位作者 Junping CAO Cailian JIN Lihong DAI Hongwei TAO 《Agricultural Biotechnology》 CAS 2018年第4期108-109,249,共3页
In September 2011, an infectious disease suspected to be postweaning multisystemic wasting syndrome (PMWS) broke out in some pig farm in Taizhou. The inguinal lymph node, liver and lung tissues were collected and gr... In September 2011, an infectious disease suspected to be postweaning multisystemic wasting syndrome (PMWS) broke out in some pig farm in Taizhou. The inguinal lymph node, liver and lung tissues were collected and grinded into tissue suspension. The suspension was subjected to PCR detection, and the positive product was sequenced. The suspension of positive samples was filtered with 0.22 μm filter membrane, and the filtrate was inoculated onto PK15 cells. After five generations of blind passages, the cell viral liquid was collected and extracted for DNA, which was subjected to PCR detection and indirect immunofluorescence. The results showed that the isolate was porcine circovirus type 2 (PCV2) and designated as TAIZ110926. The target sequence was committed to NCBI with a serial number: KF039888. 展开更多
关键词 Porcine circovirus type 2 ISOLATION identification Target sequence
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基于Span-ASTE的可解释性政府多对象态度识别模型研究
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作者 曾江峰 程征 +1 位作者 黄泳潼 段尧清 《情报理论与实践》 CSSCI 北大核心 2024年第5期175-182,共8页
[目的/意义]在政府态度识别研究中,针对没有考虑到新闻文本中可能存在多个评价对象、政府态度识别结果可解释性不强等问题,基于Span-ASTE构建政府态度识别模型,提升态度识别效果。[方法/过程]首先,采用BERT提取词级别特征,基于跨度转化... [目的/意义]在政府态度识别研究中,针对没有考虑到新闻文本中可能存在多个评价对象、政府态度识别结果可解释性不强等问题,基于Span-ASTE构建政府态度识别模型,提升态度识别效果。[方法/过程]首先,采用BERT提取词级别特征,基于跨度转化为跨度特征表示;然后,联合方面术语和观点术语提取任务提取评价对象和态度描述语,利用双通道跨度剪枝策略筛选得到对象和态度描述语候选池;最后,结合候选池中的对象和态度描述语计算得到态度极性结果。[结果/结论]以美国国务院新闻文本为实验数据进行实验验证。实验结果表明:Span-ASTE在进行政府态度识别时具有一定优越性。相比于效果较好的对比模型,其精确率、召回率和F1值分别提升了约15.68%、19.37%和17.48%;在进行多对象态度识别时同样具有良好的性能表现;态度描述语可为态度极性的判断提供解释依据。[局限]政府态度识别效果还有待进一步提升,且数据规模较为有限,未来可尝试对数据集进行扩充。 展开更多
关键词 Span-astE 政府态度 态度识别 多对象 可解释性
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Newly-generated Seismic Rupture Zone:Identification,Type Division and Seismogeological Significance
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作者 Xiang Hongfa, Zhang Wanxia, Guo Shunmin and Xu XiweiInstitute of Geology, China Seismological Bureau, Beijing 100029, China 《Earthquake Research in China》 2000年第1期66-78,共13页
The results of geological research show that those phenomena such as surface geology,geomorphology,deep geophysical field,and time-space distribution of seismicities can be usedas the main seismogeological indicators ... The results of geological research show that those phenomena such as surface geology,geomorphology,deep geophysical field,and time-space distribution of seismicities can be usedas the main seismogeological indicators to identify the newly-generated seismic rupture zone(NSRZ).According to their formation and evolution process,the NSRZs can be divided intothree types:pre-rupture-isolated,quasi-rupture-discontinuous and major-rupture-connected.In a pre-rupture-isolated NSRZ,the seismicity is dominated by medium-small earthquakes.In a quasi-rupture-discontinuous NSRZ,the frequency and intensity of strong earthquakesincrease and there may even be the largest earthquake to occur.A major-rupture-connectedNSRZ is the segment where rupture has entered the mature stage;in such a zone,theintensity and duration of seismic activity depend on the constitutive condition and regionalstress field in the zone. 展开更多
关键词 Newly-generated SEISMIC RUPTURE zone (NSRZ) identification type DIVISION Seismogeological SIGNIFICANCE
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Quantitative identification of coal-type gas and oil-type gas in source-mixed gas at the northern margin of Qaidam Basin 被引量:1
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作者 Bao Yuan Wei Chongtao +2 位作者 Peng Dehua Jiang Bo Wang Chaoyong 《International Journal of Mining Science and Technology》 SCIE EI 2013年第3期435-439,共5页
The current study tested the gas component and carbon isotopic composition of gas samples from 6 oilgas fields at the northern margin of Qaidam Basin, and established a chart to quantitatively identify the mixing rati... The current study tested the gas component and carbon isotopic composition of gas samples from 6 oilgas fields at the northern margin of Qaidam Basin, and established a chart to quantitatively identify the mixing ratio of source-mixed gas. Besides, this research quantitatively investigated the natural gas generated by different types of organic matter. The results show that different ratios of source-mixed gas exist in the 6 oil-gas fields at the northern margin of Qaidam Basin. Among them, Mabei has the highest mixing ratio of coal-type gas, followed by Nanbaxian, Mahai, Lenghu-4, Lenghu-3 and Lenghu-5, with the ratios of coal-type gas 91%, 87%, 83%, 66%, 55% and 36%, respectively. Lenghu-3 and Lenghu-4 oil-gas fields were mainly filled by coal-type gas earlier. For Lenghu-3, the gas was mainly generated from low matured source rocks in lower Jurassic Series of Lengxi sub-sag. For Lenghu-4, the gas was mainly generated from humus-mature source rocks in lower Jurassic Series of the northern slope of Kunteyi sub-sag. Gas in Lenghu-5 was mainly later filled oil-type gas, which was generated from high matured sapropelics in lower Jurassic Series of Kunteyi sub-sag. Earlier filled coal-type gas was the main part of Mahai, Nanbaxian and Mabei oil-gas fields. Gas source of Mahai was mainly generated from high mature humics in lower Jurassic Series of Yibei sub-sag; for Nanbaxian, the gas was mainly generated from high matured humics in middle-lower Jurassic Series of Saishiteng sub-sag; for Mabei, the gas was mainly generated from humus-mature source rocks in middle Jurassic Series of Yuqia sub-sag. 展开更多
关键词 Source-mixed gas Quantitative identification Coal-type gas Oil-type gas Northern margin of Qaidam Basin
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Identification of Lubricating Oil Additives Using XGBoost and Ant Colony Optimization Algorithms
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作者 Xia Yanqiu Cui Jinwei +2 位作者 Xie Peiyuan Zou Shaode Feng Xin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期158-167,共10页
To address the problem of identifying multiple types of additives in lubricating oil,a method based on midinfrared spectral band selection using the eXtreme Gradient Boosting(XGBoost)algorithm combined with the ant co... To address the problem of identifying multiple types of additives in lubricating oil,a method based on midinfrared spectral band selection using the eXtreme Gradient Boosting(XGBoost)algorithm combined with the ant colony optimization(ACO)algorithm is proposed.The XGBoost algorithm was used to train and test three additives,T534(alkyl diphenylamine),T308(isooctyl acid thiophospholipid octadecylamine),and T306(trimethylphenol phosphate),separately,in order to screen for the optimal combination of spectral bands for each additive.The ACO algorithm was used to optimize the parameters of the XGBoost algorithm to improve the identification accuracy.During this process,the support vector machine(SVM)and hybrid bat algorithms(HBA)were included as a comparison,generating four models:ACO-XGBoost,ACO-SVM,HBA-XGboost,and HBA-SVM.The results showed that all four models could identify the three additives efficiently,with the ACO-XGBoost model achieving 100%recognition of all three additives.In addition,the generalizability of the ACO-XGBoost model was further demonstrated by predicting a lubricating oil containing the three additives prepared in our laboratory and a collected sample of commercial oil currently in use。 展开更多
关键词 lubricant oil additives fourier transform infrared spectroscopy type identification ACO-XGBoost combinatorial algorithm
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山东省地域功能类型识别与发展路径研究
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作者 刘兆德 延丽晶 +2 位作者 刘强 陈素青 陈有川 《国土与自然资源研究》 2025年第2期1-6,共6页
文章通过构建地域功能评价指标体系,采用Arc GIS自然断裂点分级法,分析了2020年山东省90个县区农业生产、非农生产、社会保障和生态服务4类功能的空间格局特征,定量识别了主导功能类型。研究表明,(1)地域功能差异性和空间集聚性特征明显... 文章通过构建地域功能评价指标体系,采用Arc GIS自然断裂点分级法,分析了2020年山东省90个县区农业生产、非农生产、社会保障和生态服务4类功能的空间格局特征,定量识别了主导功能类型。研究表明,(1)地域功能差异性和空间集聚性特征明显,非农生产与社会保障功能在空间分布上具有相似性,东部沿海和胶济沿线地区的两类功能指数较高,农业生产功能较高的区域集中在省会经济圈的西北部和鲁南经济圈的西部地区,胶东丘陵地区、泰鲁沂山地丘陵地区以及沿黄河和运河地区的生态服务功能较高。(2)地域功能类型可以分为7类,不同类型县区发展路径不一。农业生产主导、弱综合型县区是重要的农业生产地区;非农生产主导、强综合型、非农生产-社会保障型县区是县域经济发展的重点地区;生态服务主导型、社会保障-生态服务型县区是生态保护格局的主体。 展开更多
关键词 地域功能 类型识别 发展路径 山东省
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桂中坳陷下石炭统鹿寨组一段页岩类型划分与测井识别
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作者 黄玉越 王贵文 +6 位作者 匡立春 覃英伦 王松 党文乐 卓色强 毕少琛 赖锦 《古地理学报》 北大核心 2025年第1期256-270,共15页
桂中坳陷柳城北区块下石炭统鹿寨组页岩气取得突破,有望成为四川盆地以外海相页岩气的接替领域。但受地层非均质性及纵横向相变频繁的制约,开展页岩类型识别和储集层评价存在困难。文中建立了基于“矿物组分+TOC含量”的页岩类型划分方... 桂中坳陷柳城北区块下石炭统鹿寨组页岩气取得突破,有望成为四川盆地以外海相页岩气的接替领域。但受地层非均质性及纵横向相变频繁的制约,开展页岩类型识别和储集层评价存在困难。文中建立了基于“矿物组分+TOC含量”的页岩类型划分方案,利用元素—矿物转换最优化方程和BP神经网络模型分别实现页岩成分和TOC含量的测井识别与预测,并采用成像测井动态切片和纽扣电极视电导率图像2种方法识别表征页岩纹层。通过精细刻画不同页岩类型的纹层发育程度和含气性特征,阐明了研究区有利页岩类型及分布特征。研究表明:鹿寨组一段发育5种典型页岩类型。受沉积古环境控制,页岩分布呈现出较强的纵向非均质性。鹿寨组一段整体处于下斜坡相沉积环境,纵向上①至⑦小层沉积水体逐渐变浅,灰质含量减少而陆源碎屑供给增多,总有机碳含量也逐渐降低,页岩类型由富有机质硅质混合页岩、富有机质黏土质混合页岩逐渐相变为含有机质硅质混合页岩。其中③小层中富有机质硅质混合页岩与富有机质黏土质混合页岩的页岩组合类型有机质丰度高,纹层组合类型及发育程度较优,整体含气量和脆性均较高,为研究区的有利页岩类型。 展开更多
关键词 页岩类型 测井识别 纹层 BP神经网络 鹿寨组 下石炭统 桂中坳陷
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慢性乙型肝炎中医证型与HLA-A24、CW1基因及ALT、AST相关性研究 被引量:2
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作者 杨小蓉 蔡祥胜 +2 位作者 卢汉威 黄演婷 陈小明 《中医药临床杂志》 2021年第7期1317-1321,共5页
目的:探讨宿主基因HLA-A24、CW1表达、HBV-DNA荧光定量及生化指标ALT、AST变化与慢性乙型肝炎中医临床各证型的相关性。方法:收集符合标准的98例乙型肝炎患者按照中医辨证分型分为肝胆湿热、肝郁脾虚、肝肾阴虚、瘀血阻络及脾肾阳虚5种... 目的:探讨宿主基因HLA-A24、CW1表达、HBV-DNA荧光定量及生化指标ALT、AST变化与慢性乙型肝炎中医临床各证型的相关性。方法:收集符合标准的98例乙型肝炎患者按照中医辨证分型分为肝胆湿热、肝郁脾虚、肝肾阴虚、瘀血阻络及脾肾阳虚5种证型,设40名健康人为正常对照组。实时荧光定量PCR检测血清中的乙肝病毒定量(HBV-DNA)水平及白细胞中的HLA-A24和CW1基因水平,全自动生化分析仪上检测血清中丙氨酸氨基转移酶(ALT)和门冬氨酸氨基转移酶(AST),并分析相关因素与不同中医证型的相关性。结果:HBV-DNA定量检测结果:四组证型之间差异无统计学意义(P>0.05);HLA-A24定量结果:以脾肾阳虚证型最低,四组证型与正常对照组相比较,结果差异有统计学意义(P<0.05);HLA-CW1定量结果以肝胆湿热最低,与肝郁脾虚及脾肾阳虚组之间差异有统计学意义(P<0.05);ALT定量结果以脾肾阳虚证最高,与其它三组(肝郁脾虚、肝肾阴虚及瘀血阻络)结果相比较有统计学意义(P<0.05);AST定量结果以脾肾阳虚证最高,与其它三组(肝胆湿热、肝肾阴虚及瘀血阻络)结果比较差异有统计学意义P<0.05)。相关性比较:HBV-DNA定量与ALT及AST呈正相关(P<0.05);HLA-CW1与HLA-A24呈正相关。结论:不同中医证型乙型肝炎患者结局不同,通过HBV-DNA、肝酶及HLA-A24及HLA-CW1的联合检测可以为临床慢性乙型肝炎中医证型分型提供一个方向性指导。 展开更多
关键词 乙型肝炎 中医证型 HLA-CW1、A24基因表达 ALT ast
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Genetic Variation of Porcine Circovirus Type 2 Isolate 201105ZJ
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作者 王小敏 何孔旺 +5 位作者 汪伟 周忠涛 杨光远 茅爱华 俞正玉 倪艳秀 《Agricultural Science & Technology》 CAS 2014年第11期1860-1864,1887,共6页
[Objective] This study aimed to investigate the genetic variation of porcine circovirus type 2 (PCV2) in China. [Method] The strain was isolated from infected samples by cel passage and preliminarily identified by P... [Objective] This study aimed to investigate the genetic variation of porcine circovirus type 2 (PCV2) in China. [Method] The strain was isolated from infected samples by cel passage and preliminarily identified by PCR and IFA. Ful-length genome of the isolated strain was obtained by specific amplification for homology and phylogenetic analysis. [Result] A PCV2 strain was successful y isolated and named 201105ZJ, which could proliferate in PK15 cel lines. Specific fragments could be amplified by specific PCR assay. According to results of IFA assay, specif-ic immunofluorescence was observed; the TCID50 was low (102.67); the ful-length genome sequence of the isolated strain was 1 768 bp, sharing 94.1%-96.8% ho-mology with 13 reference strains; to be specific, the isolated strain exhibited the highest homology of 96.8% with AF055392PCV2a; the isolated strain 201105ZJ and reference strain AF055392 belonged to genotype PCV2a, exhibiting a distant genetic relationship with genotype PCV2c. [Conclusion] Characteristics of genetic variation of PCV2 isolate 201105ZJ provided theoretical basis for vaccine development, investi-gation of PCV2 pathogenesis, and prevention and control of porcine circovirus-as-sociated diseases (PCVAD) in East China. 展开更多
关键词 Porcine circovirus type 2 Isolation identification Genetic variation
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肝硬化不同证型对 AST ALT 及 AST/ALT 比值的影响 被引量:10
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作者 朱方石 张旭东 陆伟 《辽宁中医杂志》 CAS 北大核心 1997年第8期339-340,共2页
本文对89例6种证型肝硬化患者血清AST、ALT检测及AST/ALT比值分析显示:AST、ALT及AST/ALT比值均高于正常,其升高幅度以肝郁脾虚型为最低,以肝肾阴虚型(AST、AST/ALT)和气滞血瘀型(ALT... 本文对89例6种证型肝硬化患者血清AST、ALT检测及AST/ALT比值分析显示:AST、ALT及AST/ALT比值均高于正常,其升高幅度以肝郁脾虚型为最低,以肝肾阴虚型(AST、AST/ALT)和气滞血瘀型(ALT)为最高,除肝郁脾虚型AST、ALT及湿热蕴结型ALT与正常人无显著差异外(P>0.05),其余各证型的各项指标与正常人比较均有显著性差异(P<0.05和0.01)。研究表明,肝硬化证型不同,肝损害程度不一,随着中医病理发展和证型的变化,AST、ALT及AST/ALT比值逐渐升高,仍呈由代偿期的肝郁脾虚型逐渐向失代偿期水湿内停、脾肾阳虚和肝肾阴虚型递增趋势,但ALT在证型中呈台阶式渐升,似乎无规律。因此,可考虑将AST及AST/ALT比值作为肝硬化辨证分型诊断的客观指标之一。 展开更多
关键词 ast ALT 证型 肝硬变 病理学
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Identification and Typing of Respiratory Adenoviruses in Guangzhou, Southern China Using a Rapid and Simple Method 被引量:11
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作者 Guiyuan Han Hongling Niu +8 位作者 Suhui Zhao Bing Zhu Changbing Wang Yungang Liu Mingjie Zhang Shu Yang Feitong Liu Chengsong Wan Qiwei Zhang 《Virologica Sinica》 SCIE CAS CSCD 2013年第2期103-108,共6页
Human adenoviruses (HAdVs), especially HAdV-B3, -E4 and -B7, are associated with Acute Respiratory Disease in Chinese children, and occasionally in adults. In order to establish and document the profiles of the respir... Human adenoviruses (HAdVs), especially HAdV-B3, -E4 and -B7, are associated with Acute Respiratory Disease in Chinese children, and occasionally in adults. In order to establish and document the profiles of the respiratory adenovirus pathogen among children in Guangzhou, Southern China, a rapid, simple and practical method for identification and typing of respiratory adenoviruses was developed and evaluated. One pair of universal PCR primers was designed according to the conserved region of the hexon gene, which can detect not only HAdV-B3, -E4 and -B7, but also HAdV-B14, -F40 and -F41, with a specific 300bp PCR product. Three pairs of type-specific PCR primers were also designed according to the hypervariable regions of the hexon gene to type HAdV-B3, -E4 and -B7 by three independent PCR reactions, making it easy to optimize the PCR conditions. By using this method, one hundred throat swab specimens collected during Oct 2010 to Dec 2011 and suspected of being positive for adenoviral infection were identified and typed for adenoviruses. Of these samples, fifty-five were adenovirus-positive. The most common HAdV type was HAdV-B3, identified in 92.7% of samples, which is not only consistent with the data reported in 2004-2006, but also consistent with the recent report in Hangzhou, eastern China, indicating that HAdV-B3 has been circulating in Guangzhou, and maybe in eastern China, for many years. The method for the respiratory adenovirus identification and typing we developed is rapid, simple and practical, which has a potential in the real-time surveillance of circulating adenovirus strains and also to provide etiological evidence for the adenovirus-relative disease control and prevention in China. 展开更多
关键词 Molecular epidemiology identification TYPING Southern China
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Genetic types and distribution of shallow-buried natural gases 被引量:5
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作者 Gao Yang Jin Qiang Zhu Guangyou 《Petroleum Science》 SCIE CAS CSCD 2010年第3期347-354,共8页
Great volumes of shallow-buried (〈2,000 m) natural gases which are mainly composed of biogases and low-mature gases have been found in the Mesozoic-Cenozoic sedimentary basins in China. Many shallow gas reservoirs ... Great volumes of shallow-buried (〈2,000 m) natural gases which are mainly composed of biogases and low-mature gases have been found in the Mesozoic-Cenozoic sedimentary basins in China. Many shallow gas reservoirs in China are characterized by coexistence of biogas and low-mature gas, so identifying the genetic types of shallow gases is important for exploration and development in sedimentary basins. In this paper, we study the gas geochemistry characteristics and distribution in different basins, and classify the shallow gas into two genetic types, biogas and low-mature gas. The biogases are subdivided further into two subtypes by their sources, the source rock-derived biogas and hydrocarbon-derived biogas. Based on the burial history of the source rocks, the source rock-derived biogases are divided into primary and secondary biogas. The former is generated from the source rocks in the primary burial stage, and the latter is from uplifted source rocks or those in a secondary burial stage. In addition, the identifying parameters of each type of shallow gas are given. Based on the analysis above, the distributions of each type of shallow gas are studied. The primary biogases generated from source rocks are mostly distributed in Quaternary basins or modem deltas. Most of them migrate in watersoluble or diffused mode, and their migration distance is short. Reservoir and caprock assemblages play an important role in primary biogas accumulation. The secondary biogases are distributed in a basin with secondary burial history. The oil-degraded biogases are distributed near heavy oil pools. The low-mature gases are widely distributed in shallow-buried reservoirs in the Meso-Cenozoic basins. 展开更多
关键词 Primary biogas secondary biogas oil-degraded biogas low-mature gas genetic type gas identification gas accumulation DISTRIBUTION
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Identification and Evaluation of Low Resistivity Pay Zones by Well Logs and the Petrophysical Research in China 被引量:3
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作者 Mao Zhiqiang Kuang Lichun +3 位作者 Xiao Chengwen Li Guoxin Zhou Cancan Ouyang Jian 《Petroleum Science》 SCIE CAS CSCD 2007年第1期41-48,共8页
This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log ... This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log response of the low resistivity pay zones discovered and evaluated in recent years, as well as the problems in recognizing and evaluating low resistivity pay zones by well logs. The research areas mainly include the Neogene formations in the Bohai Bay Basin, the Triassic formations in the northern Tarim Basin and the Cretaceous formations in the Junggar Basin, The petrophysical research concerning recognition and evaluation of the low resistivity pays, based on their genetic types, is introduced in this paper. 展开更多
关键词 Low-resistivity pay zone in China origin and type petrophysical research identification and evaluation by well logs
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Genetic type and source of natural gas in the southern margin of Junggar Basin, NW China 被引量:2
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作者 CHEN Jianping WANG Xulong +4 位作者 NI Yunyan XIANG Baoli LIAO Fengrong LIAO Jiande ZHAO Changyi 《Petroleum Exploration and Development》 2019年第3期482-495,共14页
Natural gas has been discovered in many anticlines in the southern margin of the Junggar Basin. However, the geochemical characteristics of natural gas in different anticlines haven’t been compared systematically, pa... Natural gas has been discovered in many anticlines in the southern margin of the Junggar Basin. However, the geochemical characteristics of natural gas in different anticlines haven’t been compared systematically, particularly, the type and source of natural gas discovered recently in Well Gaotan-1 at the Gaoquan anticline remain unclear. The gas composition characteristics and carbon and hydrogen isotope compositions in different anticlines were compared and sorted systematically to identify genetic types and source of the natural gas. The results show that most of the gas samples are wet gas, and a few are dry gas;the gas samples from the western and middle parts have relatively heavier carbon isotope composition and lighter hydrogen isotope composition, while the gas samples from the eastern part of southern basin have lighter carbon and hydrogen isotope compositions. The natural gas in the southern margin is thermogenic gas generated by freshwater-brackish water sedimentary organic matter, which can be divided into three types, coal-derived gas, mixed gas and oil-associated gas, in which coal-derived gas and mixed gas take dominance. The Jurassic coal measures is the main natural gas source rock in the southern margin, and the Permian lacustrine and the Upper Triassic lacustrine-limnetic facies source rocks are also important natural gas source rocks. The natural gas in the western part of the southern margin is derived from the Jurassic coal measures and the Permian lacustrine source rock, while the natural gas in the middle part of the southern margin is mainly derived from the Jurassic coal measures, partly from the Permian and/or the Upper Triassic source rocks, and the natural gas in the eastern part of the southern margin is originated from the Permian lacustrine source rock. The natural gas in the Qingshuihe oil and gas reservoir of Well Gaotan-1 is a mixture of coal-derived gas and oil-associated gas, of which the Jurassic and Permian source rocks contribute about half each. 展开更多
关键词 southern JUNGGAR Basin NATURAL GAS hydrogen ISOTOPE carbon ISOTOPE NATURAL GAS genetic type GAS SOURCE identification JURASSIC coal measures
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Messenger RNA Profiling for Forensic Body Fluid Identification: Research and Applications 被引量:3
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作者 WANG Zheng ZHANG Su-hua +2 位作者 ZHOU Di ZHAO Shu-min LI Cheng-tao 《法医学杂志》 CAS CSCD 2013年第5期368-374,共7页
Identifying the origin of body fluids left at a crime scene can give a significant insight into crime scene reconstruction by supporting a link between sample donors and actual criminal acts.However,the conventional b... Identifying the origin of body fluids left at a crime scene can give a significant insight into crime scene reconstruction by supporting a link between sample donors and actual criminal acts.However,the conventional body fluid identification methods are prone to various limitations,such as time consumption,intensive labor,nonparallel manner,varying degrees of sensitivity and limited specificity.Recently,the analysis of cell-specific messenger RNA expression(mRNA profiling)has been proposed to supplant conventional methods for body fluid identification.Since 2011,the collaborative exercises have been organized by the European DNA Profiling Group(EDNAP)in order to evaluate the robustness and reproducibility of mRNA profiling for body fluid identification.The major advantages of mRNA profiling,compared to the conventional methods,include higher sensitivity,greater specificity,the ability of detecting several body fluids in one multiplex reaction,and compatibility with current DNA extraction and analysis procedure.In the current review,we provided an overview of the present knowledge and detection methodologies of mRNA profiling for forensic body fluid identification and discussed its possible practical application to forensic casework. 展开更多
关键词 法医 医疗卫生 医学研究 医疗发展
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