检索结果-南通市图书馆

Insights into Pore Structure and Fractal Characteristics of the Lower Cambrian niutitang Formation Shale on the Yangtze Platform,South China

在线全文

学校读者我要写书评

暂无评论

Journal of Earth Science 2020年第1期31卷 169-180页

作者： Zixuan Liu Detian Yan xing niu Key Laboratory of Tectonics and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan 430074China School of Earth Resources China University of GeosciencesWuhan 430074China Sedimentary Basin Research Center Yangtze UniversityWuhan 430074China

Shales from the Lower Cambrian niutitang Formation of Yangtze Platform have been widely investigated due to its shale gas *** better illustrate the pore structure and fractal characteristics of shale,a series of experiments were conducted on outcrop samples from the Lower Cambrian niutitang Formation on Yangtze Platform,including X-ray diffraction(XRD),field-emission scanning electron microscopy(FE-SEM) and low-temperature nitrogen ***-Halsey-Hill(FHH) model was adopted to calculate the fractal ***,the relationships between fractal dimensions and pore structure parameters and mineral composition are ***-SEM observation results show that interparticle pores are most developed in shale,followed by intraparticle *** study identified the fractal dimensions D1(ranging from 2.558 0 to 2.710 2) and D2(ranging from 2.541 5 to 2.765 2).The pore structure of the niutitang Formation shale is primarily controlled by quartz and clay *** dimensions are able to characterize the pore structure complexity of niutitang Formation shale because D1 and D2 correlate well with average pore diameter and quartz content.

关键词： niutitang Formation Yangtze area shale pore structure fractal features

Development and Validation of a Recombinant Envelop Glycoprotein Based Indirect Enzyme-Linked Immunosorbent Assay to Detect the Antibody to REV

在线全文

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2010年第3期9卷 432-439页

作者： ZHANG Wen-juan PEI Zong-fei SHI Feng niu xing niu Zhong-xiang College of Veterinary Medicine Shandong Agricultural University Tai＇an 271018 P.R.China Veterinary Department Shandong Vocational Animal Science and Veterinary College Weifang 261000 P.R.China

Based on the antigenic analysis of Reticuloendotheliosis virus （REV） envelop glycoprotein （env） protein, an alternative indirect enzyme-linked immunosorbent assay （ELISA） for detection of REV antibody was developed using a truncated env protein of REV produced in Escherichia coli. This assay was validated by comparison with an indirect immunofluorescence assay （IFA） and a REV-based ELISA. The diagnostic sensitivity （DSN）, specificity （DSP） and accuracy of the env indirect-ELISA （ienv-ELISA） were 93.7, 93.3 and 93.6% compared with IFA on 1 380 field serum samples, and 84.8, 95.2 and 91.7% compared with the REV-based ELISA on 96 field sera, respectively. Cross-reactivity assay showed that this assay was REV-specific. Repeatability test revealed that the coefficients of variation of positive sera within and between runs were less than 15%. This method is simpler to produce and perform, time-saving and suitable for large scale survey of REV antibody at low cost.

关键词： REV env protein prokaryotic expression indirect ELISA antibody detection

Metabolic engineering for the microbial production of isoprenoids:Carotenoids and isoprenoid-based biofuels

在线全文

学校读者我要写书评

暂无评论

Synthetic and Systems Biotechnology 2017年第3期2卷 167-175页

作者： Fu-xing niu Qian Lu Yi-Fan Bu Jian-Zhong Liu Biotechnology Research Center and Biomedical Center School of Life SciencesSun Yat-sen UniversityGuangzhou 510275China South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center School of Life SciencesSun Yat-sen UniversityGuangzhou 510275China

Isoprenoids are the most abundant and highly diverse group of natural *** isoprenoids have been used for pharmaceuticals,nutraceuticals,flavors,cosmetics,food additives and *** and isoprenoid-based biofuels are two classes of important *** isoprenoids have been produced microbially through metabolic engineering and synthetic biology ***,we briefly review the engineered biosynthetic pathways in well-characterized microbial systems for the production of carotenoids and several isoprenoid-based biofuels.

关键词： Carotenoids Isoprenoid-based biofuel Metabolic engineering Synthetic biology

Genomic and transcriptional changes in response to pinene tolerance and overproduction in evolved Escherichia coli

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Synthetic and Systems Biotechnology 2019年第3期4卷 113-119页

作者： Fu-xing niu Yuan-Bin Huang Liang-Nian Ji Jian-Zhong Liu Institute of Synthetic Biology MOE Key Laboratory of Bioinorganic and Synthetic ChemistrySchool of Life SciencesSun Yat-Sen UniversityGuangzhou 510275China

α-Pinene is an important monoterpene,which is widely used as a flavoring agent and in fragrances,pharmaceuticals and *** an evolved strain Escherichia coli YZFP,which had higher tolerance to pinene and titer,has been successfully used to produce high levels of pinene,the pinene titer is much lower than that of hemiterpene(isoprene)and sesquiterpenes(farnesene)to ***,the overall cellular physiological and metabolic changes caused by higher tolerance to pinene and overproduction of pinene remains *** reveal the mechanism of Escherichia coli YZFP with the higher tolerance to pinene and titer,a comparative genomics and transcriptional level analyses combining with CRISPR activation(CRISPRa)and interference(CRISPRi)were carried *** results show that the tolerance to pinene and the overproduction of pinene in *** may be associated with:1)the mutations of the DXP pathway genes,the rpoA and some membrane protein genes,and their upregulations of transcription levels;and 2)the mutations of some genes and their downregulation of transcriptional *** comparative omics analyses provided some genetic modification strategies to further improve pinene *** of the mutated cbpA,tabA,pitA,rpoA,sufBCDS,mutS,ispH,oppF,dusB,dnaK,dxs,dxr and flgFGH genes further improved pinene *** study also demonstrated that combining comparative omics analysis with CRISPRa and CRISPRi is an efficient technology to quickly find a new metabolic engineering strategy.

关键词： Comparative omics analysis CRISPRa CRISPRi Pinene Escherichia coli Biosynthesis

Development background of Mesozoic high-quality source rocks: Evidence from microfossils in North Carnarvon Basin, Australia

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Research 2019年第1期4卷 71-83页

作者： xing niu Xianghua Yang Detian Yan xinguo Zhuang Bo Wang Shenjun Huo Xiaoming Xu Key Laboratory of Tectonics and Petroleum Resources of the Ministry of Education China University of Geosciences430074WuhanHubei ProvinceChina Faculty of Earth Resources China University of Geosciences430074WuhanHubei ProvinceChina CNOOC Research Institute Company Limited Beijing100028China

Based on numerous microfossils in Mesozoic of North Carnarvon Basin in Australia,the Mesozoic paleoclimate and paleoenvironment were analyzed,the paleogeographic background and development model of Mesozoic high-quality source rocks were investigated and *** of microfossil species and their relative contents in Mesozoic different intervals indicates changes of paleoclimate and *** paleoclimate shows a cycle variation of aridehumidearidehumid,the regression occurred in the Early TriassiceLate Triassic and the transgression occurred in the Late TriassiceLate *** sedimentary facieses including delta facies,littoral facies,restricted sea facies and open sea facies were developed in the *** open sea was mainly developed in the Early Triassic,the delta was distributed in the MiddleeLate Triassic,the restricted sea was especially well developed in the Jurassic,and the restricted sea and open sea were mainly distributed in the *** of microfossil assemblage in these four sedimentary facies are dramatically *** the delta facies,littoral facies,restricted sea facies to open sea facies,content of pollen gradually decreases,but content of the dinoflagellate+acritarch gradually *** delta facies and littoral facies are dominated by the *** the restricted sea facies,content of the pollen is equivalent to that of the dinoflagellate+*** open sea facies is dominated by the dinoflagellate and *** of sediment and formation of organic matter are influenced by the paleoclimate and paleoenvironment,and type of organic matter is controlled by the microfossil *** on the palaeogeographic background,paleoclimatic condition and microfossil assemblage,two developmental models of the Mesozoic source rocks such as the development model of terrestrial organic matter under the background of large delta and the development model of mixed organic matter under the

关键词： Microfossil assemblage Sporopollen Dinoflagellate and acritarchs Paleoclimate reconstruction Evolution of sedimentary environment Development model of source rocks Mesozoic North Carnarvon basin

Maize Yield Gains in Northeast China in the Last Six Decades

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2013年第4期12卷 630-637页

作者： niu xing-kui XIE Rui-zhi LIU Xin ZHANG Feng-lu LI Shao-kun GAO Shi-ju Institute of Crop Sciences Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and Ecology Ministry of Agriculture College of Agronomy Agricultural University of Hebei

In 2010, Chinese maize yields increased from 961.5 kg ha-1 in 1949 to 5 453.8 kg ha-L This increase is the result of genetic improvements, an increase in nitrogen application, and refinement of planting densities. The objective of this study was to provide a theoretical basis for maize production research by analyzing the maize yield gain characteristics. Six varieties of maize were selected for the study; each selection is representative of a typical or commonly used maize variety from a specific decade, beginning from the 1950s and continuing through each decade into the 2000s. The selections and their corresponding decade were as follows： Baihe, 1950s; Jidan 101, 1960s; Zhongdan 2, 1970s; Yedan 13, 1980s; Zhengdan 958, 1990s; and Xianyu 335, 2000s. Each variety was planted under four different densities （37 500, 52 500, 67 500, and 82 500 plants ha-0 and four different nitrogen applications （0, 150, 225, and 300 kg ha-1 to study the effects on yield gain characteristics. The obtained results demonstrated that there was a maize yield increase of 123.19% between the 1950s variety and the 2000s variety. Modern Chinese maize varieties had a higher yield advantage. They also displayed the additional potential to acquire higher yield under increased planting densities and nitrogen applications. At the present cultivation levels （planting at 67 500 plants ha-~ with 225 kg ha-1 nitrogen application）, the contribution types and corresponding yield increase percentages were as follows： genetic improvement, 45.37%; agronomic-management improvement, 30.94%; and genotype× agronomicmanagement interaction, 23.69%. At high-yielding cultivation levels （planting at 82 500 plants ha-1 with 300 kg ha-1 nitrogen application）, the contribution types and corresponding yield increase percentages were as follows： genetic improvement, 31.30%; agronomic-management improvement, 36.23%; and genotype × agronomic-management interaction, 32.47%. The contribution of agronomic-management and geno

关键词： maize yield gains varieties nitrogen applications plant densities

Identification of an immune-related gene-based signature to predict prognosis of patients with gastric cancer

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2020年第8期12卷 857-876页

作者： Xiang-Ting Qiu Yu-Cui Song Jian Liu Zhen-Min Wang xing niu Jing He Department of Clinical Laboratory Linyi Central HospitalLinyi 276400Shandong ProvinceChina Department of Operating Room Linyi Central HospitalLinyi 276400Shandong ProvinceChina Second Clinical College Shengjing Hospital Affiliated to China Medical UniversityShenyang 110004Liaoning ProvinceChina Department of Pediatric Surgery Guangzhou Women and Children's Medical CenterGuangzhou Medical UniversityGuangzhou 510623Guangdong ProvinceChina

BACKGROUND Gastric cancer(GC)is the most commonly diagnosed malignancy *** evidence suggests that it is necessary to further explore genetic and immunological characteristics of *** To construct an immune-related gene(IRG)signature for accurately predicting the prognosis of patients with *** Differentially expressed genes(DEGs)between 375 gastric cancer tissues and 32 normal adjacent tissues were obtained from The Cancer Genome Atlas(TCGA)GDC data ***,differentially expressed IRGs from the ImmPort database were identified for *** univariate survival analysis was used to screen survival-related *** expressed survival-related IRGs were considered as hub *** mutations of hub IRGs were ***,hub IRGs were selected to conduct a prognostic *** operating characteristic(ROC)curve analysis was used to evaluate the prognostic performance of the *** correlation of the signature with clinical features and tumor-infiltrating immune cells was *** Among all DEGs,70 hub IRGs were obtained for *** deletions and amplifications were the two most common types of genetic mutations of hub IRGs.A prognostic signature was identified,consisting of ten hub IRGs(including S100A12,DEFB126,KAL1,APOH,CGB5,GRP,GLP2R,LGR6,PTGER3,and CTLA4).This prognostic signature could accurately distinguish patients into highand low-risk groups,and overall survival analysis showed that high risk patients had shortened survival time than low risk patients(P<0.0001).The area under curve of the ROC of the signature was 0.761,suggesting that the prognostic signature had a high sensitivity and *** regression analysis demonstrated that the prognostic signature could become an independent prognostic predictor for GC after adjustment for other clinical ***,we found that the prognostic signature was significantly correlated with macrophage *** Our study pr

关键词： Gastric cancer Immune-related genes Tumor microenvironment Immune infiltration Prognosis Signature

Studies on the Root Characteristics of Maize Varieties of Different Eras

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2013年第3期12卷 426-435页

作者： ZHANG Feng-lu niu xing-kui ZHANG Yi-ming XIE Rui-zhi LIU Xin LI Shao-kun GAO Shi-ju Key Laboratory of Crop Growth Regulation Science and Technology Department of Hebei Province/College of Agronomy Agricultural University of Hebei Institute of Crop Sciences Chinese Academy of Agriculture Sciences

Experiment was conducted at the Gongzhuling Experimental Station of Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Jilin Province, China, during 2009-2010. Six representative varieties of maize （Baihe in the 1950s, Jidan 101 in the 1960s, Zhongdan 2 in the 1970s, Yedan 13 in the 1980s, Zhengdan 958 in the 1990s, and Xianyu 335 in the 2000s） were each planted under two different densities （52 500 and 82 500 plants ha-~） and two different nitrogen application levels （150 and 300 kg ha-l）. Root characteristics and distribution among soil layers were studied by the field root digging method. The results showed that root mass increased with the process of the growth and development of the plant, and it peaked at kernel filling stage, and decreased at maturity due to the root senesces. Root mass of different maize varieties from the 1950s to 1980s had a trend of increase, while it decreased for the modern varieties. Root length and root surface areas had the similar changing trend. The study suggested that early maize varieties may have root redundancy, and reducing root redundancy may be a direction for variety improvement for high yield. Root characteristics were affected by nitrogen application level and density; modern varieties were more suitable for higher fertilizer application level and density conditions. Root characteristics distribution among soil layers decreased by an exponent equation, but the regression coefficients of different varieties were different. Though the root length density （RLD） of every soil layer of different varieties also decreased by an exponent equation, there were large variations of RLD in every part of a layer.

关键词： maize root characteristics root distribution varieties of different eras density fertility

Factors Influencing the Emergency Medical Service Response Time for Cardiovascular Disease in Guangzhou, China

在线全文

学校读者我要写书评

暂无评论

Current Medical Science 2019年第3期39卷 463-471页

作者： Xiao-qian CHEN Zi-feng LIU Shi-kun ZHONG xing-tang niu Yi-xiang HUANG Ling-ling ZHANG Department of Health Policy and Management School of Public Health Sun Yat-sen University Guangzhou 510080China Department of Medicine Guanghua School of Stomotology Hospital of Stomatology Sun Yat-sen University Guangzhou 510080 China Department of Network Management Guangzhou City Emergency Care Centre Guangzhou 510080 China Department of Plastic Surgery the First Affiliated Hospital Sun Yat-sen University Guangzhou 510080China Department of Nursing College of Nursing and Health Sciences University of Massachusetts Boston Boston 02125-3393 USA

While emergency medical service (EMS) response time (ERT) is a major factor associated with the survival of patients with cardiovascular disease (CVD), relatively few studies have explored the factors associated with ERT. This study aimed to assess the current status of ERT and to identify the factors affecting ERT in patients with CVD in China. Between January 1, 2011 and December 31, 2015, EMS responses to CVD incidents in Guangzhou, China, were examined. The primary outcome was ERT, defined as the time from receipt of an emergency call to the arrival of paramedics on the scene. Factors associated with ERT were evaluated by multivariable logistic regression. A total of 44 383 CVD incidents were analysed. The median ERT was 12.58 min (interquartile range=9.98-15.67). Among the risk factors, distance (OR=13.73, 95% CI=11.76- 16.04), level of hospital (OR=1.57, 95% CI=1.40-1.75), and site of the incident (OR=1.53, 95% CI=1.38-1.69) were the top three significant factors affecting the ERT. Our results suggest that greater attention should be given to factors affecting the ERT. It is essential to make continuous efforts to promote the development of effective interventions to reduce the response time.

关键词： emergency medical service cardiovascular disease response time factors China