期刊文献+
共找到124篇文章
< 1 2 7 >
每页显示 20 50 100
2009至2013年天津早产儿视网膜病变筛查分析(英文) 被引量:11
1
作者 韩梅 张桐梅 +2 位作者 郑军 韩泉洪 李立 《国际眼科杂志》 CAS 北大核心 2018年第9期1553-1558,共6页
目的:分析天津地区早产儿视网膜病变(ROP)筛查的结果,研究肺表面活性剂及经鼻连续正压通气(NCPAP)对于ROP的影响。方法:多中心回顾性研究。2894例早产儿(1592男婴,1 302女婴)主要来自于天津市几家大型医院,筛查时间从2009-01/2013-12,... 目的:分析天津地区早产儿视网膜病变(ROP)筛查的结果,研究肺表面活性剂及经鼻连续正压通气(NCPAP)对于ROP的影响。方法:多中心回顾性研究。2894例早产儿(1592男婴,1 302女婴)主要来自于天津市几家大型医院,筛查时间从2009-01/2013-12,对人口统计学信息,眼科检查结果和可能的全身危险因素均进行记录。孕周、出生体质量、吸氧、肺表面活性剂和NCPAP对ROP的影响进行了评估。结果:224例448眼患有ROP(7.7%)。其中,49例98眼为严重ROP。在对照组与ROP组之间呼吸窘迫综合征(RDS)、NCPAP、肺表面活性剂的应用差异有统计学意义(P<0.01)。Logistic回归分析结果表明小孕龄、低出生体质量、吸氧是导致ROP发生的危险因素。随着肺表面活性剂与NCPAP的使用率增加,吸氧率逐渐下降,ROP的发生率也在下降。结论:低出生体质量、低孕龄、吸氧史与ROP的发生密切相关,肺表面活性剂与NCPAP的使用可能是降低ROP发生的因素。 展开更多
关键词 早产儿视网膜病变 发生率 危险因素 肺表面活性剂 经鼻连续正压通气
暂未订购
Phase waves of local depolarization in biological tissues object speckle fields.Fundamental and applied aspects
2
作者 Yurii Ushenko Alexander Ushenko +9 位作者 Alexander Dubolazov Mykhaylo Gorsky Irina Soltys Olexandra Litvinenko Victor Bachinsky Ivan Mikirin Olexander Salega Ivan Garasim jun zheng Lin Bin 《Journal of Innovative Optical Health Sciences》 2025年第5期113-133,共21页
Our gosl was to develop and experimentally validate a polarization-interferene method for phsae scanning of laser speckle fields generated by diffuse layers of birefringent biological tissues.This method isolates and ... Our gosl was to develop and experimentally validate a polarization-interferene method for phsae scanning of laser speckle fields generated by diffuse layers of birefringent biological tissues.This method isolates and uses new diagnostic parameters related to the"phsse WAvEs of local depolarization".We combined polarization-interferenæregistration with phase scanning of complex amplitude distributions in diffuse Laser speckle fields to detect phase waves of local depolarization in birefringent fibrillar networks of biological tisue and messure their modulation depth.This eppгоsch led to the discovery of new criteria for differentiating verious necrotic changes in diffuse histological samples of myocardial tisue from decmsed individuals with"ischemic heart disase(IHD)--cute coronary insufficiency(ACT)",even in the presænce of a high level of depolarized bckground.To evaluate the degree of necrotic changes in the optical anisotropy of difuse myocardial Layers,a new quantitative parameter--modulation depth of local depolarization wave fluctustions-has been proposed.Using this approsch,for the first time,differentiation of diffuse myocardial samples from decessed individuals with IHD and ACI was achieved witha very good 90.45%and outstanding aocuracy of 95.2%. 展开更多
关键词 olarization DEPOLARIZATION interference phase scanning optical anisotropy BIREFRINGENCE biological tissue myocardium.
原文传递
3D Jones-matrix thesiography of biological fluid facies
3
作者 Alexander Ushenko Iryna Soltys +8 位作者 Alexander Dubolazov Yuriy Ushenko Viacheslav Bilookyi Olexander Bilookyi Olexandra Litvinenko Ivan Mikirin jun zheng Zhebo Chen Lin Bin 《Journal of Innovative Optical Health Sciences》 2025年第2期76-93,共18页
A new polarization–interference biomedical diagnostic three-dimensional(3D)Jones-matrix technology with digital Fourier reconstruction of layered maps of optical anisotropy(thesiograms)of dehydrated films(facies)of b... A new polarization–interference biomedical diagnostic three-dimensional(3D)Jones-matrix technology with digital Fourier reconstruction of layered maps of optical anisotropy(thesiograms)of dehydrated films(facies)of biological fluids of human organs is presented and experimentally tested.An original model of layered phase scanning of polycrystalline architectonics of supramolecular networks of biological fluid facies is proposed for the purpose of theoretical justification and prognostic use of the obtained results.On its basis,algorithms of Jones-matrix reconstruction of thesiograms of birefringence and dichroism of facies of synovial fluid,bile and blood are found.As a result,layered thesiograms of linear and circular birefringence and dichroism of facies with different spatial–angular architectonics of supramolecular networks are experimentally obtained for the first time.Within the framework of statistical analysis of experimental data,new objective markers(asymmetry and excess of optical anisotropy parameter distributions)for diagnostics of pathological changes in the optical anisotropy of biological fluid facies were defined and clinically tested.As a result,an excellent level of balanced accuracy of the developed polarization–interference Jones-matrix method of layer-by-layer reconstruction of thesiograms of polycrystalline supramolecular networks in differential diagnostics of bile facies(cholelithiasis),synovial fluid(reactive synovitis–septic arthritis)and whole blood(follicular adenoma–papillary thyroid cancer)was achieved. 展开更多
关键词 POLARIZATION INTERFERENCE FOURIER microscopic image optical anisotropy facies of biological liquids statistical moments
原文传递
An interactive framework integrating segment anything model and structure-from-motion for three-dimensional discontinuity identification in rock masses
4
作者 Jiawei Wang jun zheng +4 位作者 Jie Hu Xiaojin Gong Qing Lü Ju Han Jialiang Sun 《International Journal of Mining Science and Technology》 2025年第10期1695-1711,共17页
The identification of rock mass discontinuities is critical for rock mass characterization.While high-resolution digital outcrop models(DOMs)are widely used,current digital methods struggle to generalize across divers... The identification of rock mass discontinuities is critical for rock mass characterization.While high-resolution digital outcrop models(DOMs)are widely used,current digital methods struggle to generalize across diverse geological settings.Large-scale models(LSMs),with vast parameter spaces and extensive training datasets,excel in solving complex visual problems.This study explores the potential of using one such LSM,Segment anything model(SAM),to identify facet-type discontinuities across several outcrops via interactive prompting.The findings demonstrate that SAM effectively segments two-dimensional(2D)discontinuities,with its generalization capability validated on a dataset of 2426 identified discontinuities across 170 outcrops.The model achieves 0.78 mean IoU and 0.86 average precision using 11-point prompts.To extend to three dimensions(3D),a framework integrating SAM with Structure-from-Motion(SfM)was proposed.By utilizing the inherent but often overlooked relationship between image pixels and point clouds in SfM,the identification process was simplified and generalized across photogrammetric devices.Benchmark studies showed that the framework achieved 0.91 average precision,identifying 87 discontinuities in Dataset-3D.The results confirm its high precision and efficiency,making it a valuable tool for data annotation.The proposed method offers a practical solution for geological investigations. 展开更多
关键词 Rock Mass DISCONTINUITY Digital outcrop model(DOM) Point clouds Large-scale model(LSM) Foundation model(FM)
在线阅读 下载PDF
食管静脉曲张套扎硬化序贯治疗的临床研究 被引量:4
5
作者 韩文 王芳 +3 位作者 陈兰兰 郑军 戴光荣 董蕾 《中国内镜杂志》 2018年第12期38-42,共5页
目的研究食管静脉曲张内镜下硬化剂注射治疗(EIS)和套扎硬化序贯治疗(ELIS)的效果。方法对2013年11月-2017年5月在该院行内镜下治疗的126例肝硬化重度食管静脉曲张患者进行回顾性分析。按内镜下治疗方法将其分为两组,即EIS组和ELIS组。... 目的研究食管静脉曲张内镜下硬化剂注射治疗(EIS)和套扎硬化序贯治疗(ELIS)的效果。方法对2013年11月-2017年5月在该院行内镜下治疗的126例肝硬化重度食管静脉曲张患者进行回顾性分析。按内镜下治疗方法将其分为两组,即EIS组和ELIS组。比较两组间治疗后72 h内再出血率、治疗后静脉曲张消失率、治疗后随访期限内静脉曲张复发率、治疗次数、硬化剂用量及其并发症发生率。结果 126例肝硬化重度食管静脉张患者EIS和ELIS治疗后总有效率分别为92.75%和98.25%,两组比较差异无统计学意义(P=0.150);随访期限内静脉曲张复发率分别为5.80%和10.52%,两组比较差异无统计学意义(P=0.328)。而在硬化剂用量及治疗次数方面,EIS和ELIS组分别为(69.12±9.45)和(38.45±13.39)ml以及(3.86±0.98)和(2.45±1.01)次,两组比较,差异均有统计学意义(P=0.000)。在72 h内再出血、急诊止血率、胸骨后疼痛、穿孔和狭窄等方面两组间比较,差异均无统计学意义。结论 EIS和ELIS治疗肝硬化门脉高压重度食管静脉曲张在疗效上无明显差异,但ELIS与EIS相比,可以明显减少硬化剂用量和治疗次数,可以彻底消除细碎的曲张静脉,阻断交通支,弥补单纯套扎治疗的不足,值得在临床推广。 展开更多
关键词 食管静脉曲张 硬化剂注射治疗 套扎治疗
暂未订购
Regulation of solvation structure and electrochemical performance optimization in Zn(NH_(2)SO_(3))_(2)-based electrolytes
6
作者 Lei Liu Ruxue Yan +6 位作者 Songyan Jiang Xiao Liu Zhonghua Zhang Xiaosong Guo Xingguang Liu jun zheng Guicun Li 《Journal of Energy Chemistry》 2025年第5期644-654,共11页
Monovalent anions,with relatively low charge density,exhibit weak bond energy with Zn^(2+)ions,which facilitates the solubility of Zn salts and the regulation of solvation structures.In this study,zinc bis(aminosulfat... Monovalent anions,with relatively low charge density,exhibit weak bond energy with Zn^(2+)ions,which facilitates the solubility of Zn salts and the regulation of solvation structures.In this study,zinc bis(aminosulfate)(Zn(NH_(2)SO_(3))_(2))with a monovalent anion,NH_(2)SO_(3)^(-),was synthesized and dissolved in different ratios of dimethyl sulfoxide(DMSO)and H_(2)O as electrolytes for Zn-ion batteries(ZIBs).From the perspective of game theory,the influences of DMSO and H_(2)O on the solvation structure and electrochemical performance of the Zn(NH_(2)SO_(3))_(2)based electrolytes has been meticulously discussed.Computations and spectra analysis indicate that DMSO molecules are reluctant to penetrate the primary solvation structure of Zn^(2+)ions.Indeed,increasing DMSO in electrolytes can induce a transition from solvent-separated ion pairs(SSIP)to contact ion pairs(CIP),resulting in an enrichment of anions in the primary solvation structure.This alteration can significantly suppress parasitic reactions,enhance nucleation density,and refine the deposition morphology during the Zn plating process,leading to superior cyclic stability and high coulombic efficiency(CE)of Zn//Cu and Zn//Zn cells.However,the enrichment of anions in the primary solvation structure also inhibits the activity of Zn^(2+)ions,amplifies the polarization effect,and engenders a sluggish ionization dynamics,resulting in the low energy conversion efficiency of the battery.These findings underscore the influence of the anion ratio within the primary solvation structure on electrochemical properties of electrolytes for ZIBs,which may be a pivotal determinant in the Zn deposition process. 展开更多
关键词 Monovalent anion Primary solvation structure Impressed current cathodic protection Game theory CIP
在线阅读 下载PDF
Molybdenum cofactor biosynthesis gene ZmCNX6 regulates vivipary and drought tolerance in maize
7
作者 Yuxin Chen Yiru Wang +4 位作者 Minghao Sun Jian Li Yang Qin Quansheng Huang jun zheng 《The Crop Journal》 2025年第5期1479-1489,共11页
Pre-harvest sprouting(PHS)or vivipary is a major problem affecting cereal quality and grain quantity and is primarily linked to the dysregulation of abscisic acid(ABA)biosynthesis in plants.Therefore,elucidating the m... Pre-harvest sprouting(PHS)or vivipary is a major problem affecting cereal quality and grain quantity and is primarily linked to the dysregulation of abscisic acid(ABA)biosynthesis in plants.Therefore,elucidating the molecular mechanisms governing seed dormancy is crucial for developing strategies to improve crop productivity.In this study,we identified a novel viviparous maize mutant,viviparous-like 5(vp-like5),which exhibits precocious germination in developing seeds.Through map-based cloning,we discovered that ZmCNX6,which encodes a small subunit of molybdopterin synthase essential for molybdenum cofactor(MoCo)biosynthesis,is the causal gene responsible for the vp-like5 phenotype.Biochemical assays have demonstrated significantly reduced activities of MoCo-dependent enzymes,including aldehyde oxidase(AO),xanthine dehydrogenase(XDH),and nitrate reductase(NR),in vplike5.AO is essential for the ABA biosynthesis,and the observed ABA deficiency in vp-like5 likely drives the viviparous phenotype.Expression analysis showed that ZmCNX6 was stably expressed during seed development,indicating its significant role in seed development.Furthermore,overexpression of ZmCNX6 not only enhanced the activities of MoCo-dependent enzymes but also improved drought tolerance in maize.Collectively,our study revealed ZmCNX6 as a multifunctional hub coordinating MoCo metabolism,ABA-dependent dormancy regulation,and abiotic stress responses,offering a potential target for simultaneously mitigating vivipary and improving drought resistance in maize. 展开更多
关键词 MAIZE VIVIPARY Molybdenum cofactor(MoCo) Abscisic acid(ABA) DROUGHT
在线阅读 下载PDF
骨外露创面扩创术修复后负压封闭引流联合局部氧疗的疗效及预后分析 被引量:10
8
作者 郑军 佟向阳 《中国现代医学杂志》 CAS 北大核心 2021年第4期86-91,共6页
目的探讨骨外露创面扩创术修复后给予负压封闭引流(VSD)联合局部氧疗的疗效及预后。方法选取2017年1月—2018年1月徐州市第一人民医院收治的88例行骨外露创面扩创修复术患者。按随机数字法分为VSD+氧疗组和机械治疗组。VSD+氧疗组行VSD... 目的探讨骨外露创面扩创术修复后给予负压封闭引流(VSD)联合局部氧疗的疗效及预后。方法选取2017年1月—2018年1月徐州市第一人民医院收治的88例行骨外露创面扩创修复术患者。按随机数字法分为VSD+氧疗组和机械治疗组。VSD+氧疗组行VSD联合局部氧疗,机械治疗组行传统清创联合换药方式治疗。比较两组创面愈合情况、临床治疗指标、创口微环境检测指标及不良反应情况。结果VSD+氧疗组临床基本愈合率较机械治疗组高(P<0.05)。VSD+氧疗组换药次数、完全愈合时间及住院时间较机械治疗组低(P<0.05)。两组渗液酸碱度、伤口温度及C反应蛋白比较,差异有统计学意义(P<0.05)。VSD+氧疗组不良反应率较机械治疗组低(P<0.05)。结论骨外露创面扩创术修复后给予VSD联合局部氧疗,能够改善创面愈合效果,改善创口微环境,提升临床治愈率和安全性。 展开更多
关键词 负压伤口疗法 物理治疗技术 局部氧疗 治疗结果 预后
暂未订购
Effect of industrial alkene ozonolysis on atmospheric H_(2)SO_(4)formation
9
作者 Xing Wang Xiaowen Shi +2 位作者 Youling Jiang Yan Ma jun zheng 《Journal of Environmental Sciences》 2025年第4期466-476,共11页
This study has employed the master chemical mechanism(MCM)to investigate the influence of the ozone oxidation pathways in the atmospheric formation of H_(2)SO_(4)from shortchain olefins in industrialized areas.In-situ... This study has employed the master chemical mechanism(MCM)to investigate the influence of the ozone oxidation pathways in the atmospheric formation of H_(2)SO_(4)from shortchain olefins in industrialized areas.In-situ H_(2)SO_(4)formation data were obtained using a high-resolution chemical ionization time-of-flight mass spectrometer,and the simulated H_(2)SO_(4)concentrations calculated using updated parameters for the MCM model exhibited good agreementwith observations.In the simulation analysis of different reaction pathways involved in H_(2)SO_(4)formation,hydroxyl radicals were found to dominate H_(2)SO_(4)production during the daytime,while olefin ozone oxidation contributed up to 65%of total H_(2)SO_(4)production during the night-time.A sensitivity analysis of the H_(2)SO_(4)production parameters has revealed a high sensitivity to changes in sulfur dioxide,and a relatively high sensitivity to olefins with fast ozonolysis reaction rates and bimolecular reaction rates of resulting stabilized Criegee Intermediates.A high relative humidity promotes daytime H_(2)SO_(4)formation,but has an inhibiting effect during the night-time due to the different dominant reaction pathways. 展开更多
关键词 Gaseous sulfuric acid Alkene ozonation reaction MCM model Sensitivity analysis
原文传递
High-responsivity and high-speed germanium photodetector for C+L application
10
作者 Yiling Hu Zhipeng Liu +6 位作者 Zhi Liu Yupeng Zhu Tao Men Guangze Zhang jun zheng Yuhua Zuo Buwen Cheng 《Journal of Semiconductors》 2025年第10期59-65,共7页
A silicon-based germanium(Ge)photodetector working for C and L bands is proposed in this paper.The device fea-tures a novel asymmetric PIN structure,which contributes to a more optimized electric field distribution in... A silicon-based germanium(Ge)photodetector working for C and L bands is proposed in this paper.The device fea-tures a novel asymmetric PIN structure,which contributes to a more optimized electric field distribution in Ge and a shorter effective width of depleted region.Meanwhile,the optical structure is designed carefully to enhance responsivity for broad-band.Under-7 V,where the weak avalanche process happens,the responsivity of our device is 1.49 and 1.16 A/W at 1550 and 1600 nm,with bandwidth of 47.1 and 44.5 GHz,respectively.These performances demonstrate the significant application poten-tial of the device in optical communication systems. 展开更多
关键词 silicon photonics germanium photodetector asymmetric structure DBR
在线阅读 下载PDF
Characterization of size-resolved aerosol hygroscopicity and liquid water content in Nanjing of the Yangtze River Delta
11
作者 Youling Jiang Yan Ma +2 位作者 jun zheng Nan Ye Cheng Yuan 《Journal of Environmental Sciences》 2025年第5期26-41,共16页
Aerosol hygroscopicity and liquid water content(ALWC)have important influences on the environmental and climate effect of aerosols.In this study,we measured the hygroscopic growth factors(GF)of particles with dry diam... Aerosol hygroscopicity and liquid water content(ALWC)have important influences on the environmental and climate effect of aerosols.In this study,we measured the hygroscopic growth factors(GF)of particles with dry diameters of 40,80,150,and 200 nm during the wintertime in Nanjing.Both the GF-derived hygroscopicity parameter(κ_(gf))and ALWC increased with particle size,but displayed differing diurnal variations,withκ_(gf)peaking around the midday,while ALWC peaking in the early morning.Nitrate,ammonium and oxygenated organic aerosols(OOA)were found as the chemical components mostly strongly correlated with ALWC.A closure study suggests that during midday photo-oxidation and nighttime high ALWC periods,theκof organic aerosols(κ_(org))was underestimated when using previous parameterizations.Accordingly,we re-constructed parameterizations forκ_(org)and the oxidation level of organics for these periods,which indicates a higher hygroscopicity of photochemically formed OOA than the aqueous OOA,yet both being much higher than the generally assumed OOA hygroscopicity.Additionally,in a typical high ALWC episode,concurrently increased ALWC,nitrate,OOA as well as aerosol surface area and mass concentrations were observed under elevated ambient RH.This strongly indicates a coupled effect that the hygroscopic secondary aerosols,in particular nitratewith strong hygroscopicity,led to large increase in ALWC,which in turn synergistically boosted nitrate and OOA formation by heterogeneous/aqueous reactions.Such interaction may represent an important mechanism contributing to enhanced formation of secondary aerosols and rapid growth of fine particulate matter under relatively high RH conditions. 展开更多
关键词 Aerosol hygroscopicity Aerosol liquid water content PHOTO-OXIDATION Aqueous/heterogeneous reactions
原文传递
Revisiting scale effect on joint roughness coefficient and shear strength considering sampling methods and geometric characteristics
12
作者 Qing Lü Xueheng Cai +2 位作者 Luxiang Wu jun zheng Bo Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期2843-2856,共14页
The scale effect on shear strength of rock joints is well-documented.However,whether scale effects are negative,positive,or even exist or not is still controversial.Joint roughness significantly influences the shear s... The scale effect on shear strength of rock joints is well-documented.However,whether scale effects are negative,positive,or even exist or not is still controversial.Joint roughness significantly influences the shear strength of rock joints.Compared to the shear tests,using the joint roughness coefficient(JRC)and its roughness parameters offers a more convenient method for describing the scale effect on shear strength.However,it is crucial to understand that the scale effect mechanisms of JRC are distinct from those of shear strength.Therefore,this paper aims to clarify these distinct mechanisms.By digitally extracting roughness parameters from granite samples,it is found that the scale effect of roughness parameters mainly comes from the sampling methods and the geometric characteristics of parameters.Furthermore,a full data sampling method considering heterogeneity is proposed to obtain more representative roughness parameters.To reveal the scale effect mechanisms of shear strength,Gaussian filtering is firstly used to separate the waviness and unevenness components of roughness,facilitating a deeper understanding of the geometric characteristics of roughness.It is suggested that the wavelength of the waviness component can reflect the scale effect on shear strength.Secondly,numerical simulations of ideal artificial joint models are conducted to validate that the wavelength of the waviness component serves as the dividing point between positive and negative scale effects.The mechanical mechanisms of positive and negative scale effects are also interpreted.Finally,these mechanisms successfully elucidate the occurrence patterns of the scale effect on natural joint profiles. 展开更多
关键词 Rock joint Joint roughness coefficient(JRC) Shear strength Scale effect
在线阅读 下载PDF
Application of 16s rDNA Sequencing in the Analysis of Pathogenic Bacteria in Sputum of Severe Bacterial Pneumonia
13
作者 jun zheng Juan Zhu +4 位作者 Bin Chen Lingxiu Chen Tian Gao Xinping Chen Tao Huang 《Advances in Microbiology》 2021年第2期109-116,共8页
<b>Objective:</b> 120 patients with severe pneumonia who were kept in the comprehensive ICU of our hospital in 2018 were selected, and 16s rDNA sequencing was performed to analyze the composition of pathog... <b>Objective:</b> 120 patients with severe pneumonia who were kept in the comprehensive ICU of our hospital in 2018 were selected, and 16s rDNA sequencing was performed to analyze the composition of pathogenic bacteria in the sputum of severe pneumonia. <b>Methods:</b> The sputum samples of patients with severe bacterial pneumonia were collected, and the diversity of pathogens in the samples was analyzed by polymerase chain reaction (PCR) amplification and high-throughput sequencing (16s rDNA PCR-DGGE). <b>Results:</b> Sequence showed that sputum samples contained a relatively large number of species, and there were many species that were not detected by sequencing. The dominant bacteria were <i>Streptococcus, Sphingomonas, Corynebacterium, Denatobacteria, Aquobacteria, Acinetobacteria, Prevotella, Klebsiella, Pseudomonas</i>, etc. <b>Conclusion:</b> Bacteria caused by sputum of severe bacterial pneumonia are complex and diverse, which provides new methods and ideas for individualized treatment of patients with severe pneumonia. 展开更多
关键词 Bacterial Severe Pneumonia SPUTUM The Pathogenic Bacterium 16s rDNA Sequencing
暂未订购
Application of 16S rDNA Sequencing Technology in the Analysis of Pathogenic Bacteria in Sputum of Severe Pneumonia
14
作者 jun zheng Juan Zhu +4 位作者 Bin Chen Lingxiu Chen Tian Gao Xinping Chen Feiyan Li 《Advances in Microbiology》 2021年第3期157-164,共8页
The diagnosis of pathogenic bacteria in severe pneumonia is difficult and the prognosis is poor. Its outcome is closely related to bacterial pathogenicity and the timeliness and pertinence of antibiotic treatment. The... The diagnosis of pathogenic bacteria in severe pneumonia is difficult and the prognosis is poor. Its outcome is closely related to bacterial pathogenicity and the timeliness and pertinence of antibiotic treatment. Therefore, early diagnosis is of great significance to the prognosis of patients. Sputum examination and culture is the gold standard for the diagnosis of pathogens of severe pneumonia. However, due to the long time of bacterial culture, the early use of antibiotics, the change of bacteria species, mixed infection and other problems, the results of bacterial culture in sputum are often false negative. With the continuous application of new molecular biology techniques in clinical detection, the classification of bacteria and microorganisms has deepened from the identification of phenotypic characteristics to the classification of gene characteristics. Sequencing analysis with 16S rDNA sequencing technology has the characteristics of high sequencing flux, large amount of data obtained, short cycle, and can more comprehensively reflect the species composition of microbial community, real species distribution and abundance information. In this paper, 16S rDNA sequencing technology was used to analyze the bacterial population composition in the sputum of severe pneumonia, and to explore a new method of etiological diagnosis. 展开更多
关键词 Bacterial Severe Pneumonia SPUTUM The Pathogenic Bacterium 16S rDNA Sequencing
暂未订购
Characteristics of one-year observation of VOCs,NOx, and O_3 at an urban site in Wuhan, China 被引量:32
15
作者 Yichang Yang Xingang Liu +5 位作者 jun zheng Qinwen Tan Miao Feng Yu Qu junling An Nianliang Cheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第5期297-310,共14页
A continuous online observation of ozone and its precursors(NOx, VOCs) was carried out in central urban Wuhan from September 2016 to August 2017. The concentration levels of ozone,NOx, VOCs and their variations in urb... A continuous online observation of ozone and its precursors(NOx, VOCs) was carried out in central urban Wuhan from September 2016 to August 2017. The concentration levels of ozone,NOx, VOCs and their variations in urban Wuhan were analyzed, as well as effects of VOCs on ozone photochemical generation and the main controlling factors for ozone production. During the observation period, the average concentrations of ozone and NOx in Wuhan was 22.63 and30.14 ppbv, respectively, and the average concentration of VOCs was 32.61 ppbv(42.3% alkanes,13.0% alkenes, 10.0% aromatics, 7.3% acetylene, 9.9% OVOCs, and 10.5% halohydrocarbons).Ozone concentration was higher in spring and summer as compared with autumn and winter,wheras VOCs and NOx concentratios were lower in spring and summer but higher in autumn and winter. Aromatics and alkenes, two of VOCs species, showed the highest contributions to ozone formation potential in Wuhan(35.7% alkenes, 35.4 aromatics, 17.5% alkanes, 8.6% OVOCs,1.6% halogenated hydrocarbons, and 1.4% acetylene). Among all VOCs species, those with the highest contribution were ethylene, m-xylene, toluene, propylene and o-xylene. The contribution of these five compounds to the total ozone formation potential concentration was 43.90%.Ozone-controlling factors in Wuhan changed within one day; during the early morning hours(6:00–9:00), VOCs/NOx was low, and ozone generation followed a VOCs-limited regime.However, during the peak time of ozone concentration(12:00–16:00), the ratio of VOCs/NOx was relatively high, suggesting that ozone generation followed a NOx-limited regime. 展开更多
关键词 OZONE NOx VOCS variation VOCS chemical CHARACTERISTICS OZONE formation mechanism WUHAN
原文传递
Laparoscopic VS open hepatectomy for hepatolithiasis: An updated systematic review and meta-analysis 被引量:45
16
作者 Hui Li jun zheng +6 位作者 Jian-Ye Cai Shi-Hui Li jun-Bin Zhang Xiao-Ming Wang Gui-Hua Chen Yang Yang Gen-Shu Wang 《World Journal of Gastroenterology》 SCIE CAS 2017年第43期7791-7806,共16页
AIM To perform a meta-analysis on laparoscopic hepatectomy VS conventional liver resection for treating hepatolithiasis.METHODS We conducted a systematic literature search on Pub Med,Embase,Web of Science and Cochrane... AIM To perform a meta-analysis on laparoscopic hepatectomy VS conventional liver resection for treating hepatolithiasis.METHODS We conducted a systematic literature search on Pub Med,Embase,Web of Science and Cochrane Library,and undertook a meta-analysis to compare the efficacy and safety of laparoscopic hepatectomy V S conventional open liver resection for local hepatolithiasis in the left or right lobe. Intraoperative and postoperative outcomes(time,estimated blood loss,blood transfusion rate,postoperative intestinal function recovery time,length of hospital stay,postoperative complication rate,initial residual stone,final residual stone and stone recurrence) were analyzed systematically.RESULTS A comprehensive literature search retrieved 16 publications with a total of 1329 cases. Meta-analysis of these studies showed that the laparoscopic approach for hepatolithiasis was associated with significantly less intraoperative estimated blood loss [weighted mean difference(WMD): 61.56,95% confidence interval(CI): 14.91-108.20,P = 0.01],lower blood transfusion rate [odds ratio(OR): 0.41,95%CI: 0.22-0.79,P = 0.008],shorter intestinal function recovery time(WMD: 0.98,95%CI: 0.47-1.48,P = 0.01),lower total postoperative complication rate(OR: 0.52,95%CI: 0.39-0.70,P < 0.0001) and shorter stay in hospital(WMD: 3.32,95%CI: 2.32-4.32,P < 0.00001). In addition,our results showed no significant differences between the two groups in operative time(WMD: 21.49,95%CI: 0.27-43.24,P = 0.05),residual stones(OR: 0.79,95%CI: 0.50-1.25,P = 0.31) and stone recurrence(OR: 0.34,95%CI: 0.11-1.08,P = 0.07). Furthermore,with subgroups analysis,our results proved that the laparoscopic approach for hepatolithiasis in the left lateral lobe and left side could achieve satisfactory therapeutic effects. CONCLUSION The laparoscopic approach is safe and effective,with less intraoperative estimated blood loss,fewer postoperative complications,reduced length of hospital stay and shorter intestinal function recovery time than with conventional approaches. 展开更多
关键词 HEPATOLITHIASIS Laparoscopic hepatectomy Conventional liver resection Systematic review Metaanalysis
暂未订购
Probabilistic assessment of tunnel convergence considering spatial variability in rock mass properties using interpolated autocorrelation and response surface method 被引量:18
17
作者 Qing Lü Zhipeng Xiao +1 位作者 jun zheng Yuequan Shang 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第6期1619-1629,共11页
This study aims at the probabilistic assessment of tunnel convergence considering the spatial variability in rock mass properties. The method of interpolated autocorrelation combined with finite difference analysis is... This study aims at the probabilistic assessment of tunnel convergence considering the spatial variability in rock mass properties. The method of interpolated autocorrelation combined with finite difference analysis is adopted to model the spatial variability of rock mass properties. An iterative procedure using the first-order reliability method(FORM) and response surface method(RSM) is employed to compute the reliability index and its corresponding design point. The results indicate that the spatial variability considerably affects the computed reliability index. The probability of failure could be noticeably overestimated in the case where the spatial variability is neglected. The vertical scale of fluctuation has a much higher effect on the probabilistic result with respect to the tunnel convergence than the horizontal scale of fluctuation. And the influence of different spacing of control points on the computational accuracy is investigated. 展开更多
关键词 Spatial VARIABILITY ROCK mass TUNNEL CONVERGENCE FORM Random field
在线阅读 下载PDF
Effect of notoginsenoside R1 on hepatic microcirculation disturbance induced by gut ischemia and reperfusion 被引量:18
18
作者 Wei-Xing Chen Fang Wang, Yu-Ying Liu, Qing-Jiang Zeng, Kai Sun, Xin Xue, Xiang Li, Ji-Ying Yang, Li-Hua An,Bai-He Hu, Jin-Hui Yang, Chuan-She Wang, Zhi-Xin Li, Lian-Yi Liu, Yan Li, jun zheng, Fu-Long Liao, Dong Han,Jing-Yu Fan, Jing-Yan Han Fang Wang +17 位作者 Yu-Ying Liu Qing-Jiang Zeng Kai Sun Xin Xue Xiang Li Ji-Ying Yang Li-Hua An Bai-He Hu Jin-Hui Yang Chuan-She Wang Zhi-Xin Li Lian-Yi Liu Yan Li jun zheng Fu-Long Liao Dong Han Jing-Yu Fan Jing-Yan Han 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第1期29-37,共9页
AIM: To assess the effect of notoginsenoside R1 on hepatic microcirculatory disturbance induced by gut ischemia/reperfusion (I/R) in mice. METHODS: The superior mesenteric artery (SMA) of C57/BL mice was ligated... AIM: To assess the effect of notoginsenoside R1 on hepatic microcirculatory disturbance induced by gut ischemia/reperfusion (I/R) in mice. METHODS: The superior mesenteric artery (SMA) of C57/BL mice was ligated for 15 min to induce gut ischemia followed by 30-rain reperfusion. In another set of experiments, R1 was continuously infused (10 mg/kg per hour) from 10 min before I/R until the end of the investigation to study the influence of R1 on hepatic microcirculatory disturbance induced by gut I/R. Hepatic microcirculation was observed by inverted microscopy, and the vascular diameter, red blood cell (RBC) velocity and sinusoid perfusion were estimated. Leukocyte rolling and adhesion were observed under a laser confocal microscope. Thirty and 60 min after reperfusion, lactate dehydrogenase (LDH), alanine aminotransferase (ALl') and aspartate transaminase (AST) in peripheral blood were determined. The expression of adhesion molecules CD11b/CD18 in neutrophils and tumor necrosis factor- alpha (TNF-α), interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1) in plasma were evaluated by flow Oltometry. E-selectin and intercellular adhesion molecule-1 (ICAM-1) in hepatic tissue were examined by immunofluorescence.RESULTS: After gut I/R, the diameters of terminal portal venules and central veins, RBC velocity and the number of perfused sinusoids were decreased, while the leukocyte rolling and adhesion, the expression of E-selectin in hepatic vessels and CD18 in neutrophils, IL-6, MCP-1, LDH, ALT and AST were increased. R1 treatment attenuated these alterations except for IL-6 and MCP-1. CONCLUSION: R1 prevents I/R-induced hepatic microcirculation disturbance and hepatocyte injury, The effect of R1 is related to its inhibition of leukocyte rolling and adhesion by inhibiting the expression of E-selectin in endothelium and CD18 in neutrophils. 展开更多
关键词 ISCHEMIA/REPERFUSION Notoginsenoside R1 Leukoytes adhesion E-SELECTIN Hepatic injury
暂未订购
Modulating effects of Astragalus polysaccharide on immune disorders via gut microbiota and the TLR4/NF-κB pathway in rats with syndrome of dampness stagnancy due to spleen deficiency 被引量:15
19
作者 Wenxiao ZHAO Chenchen DUAN +7 位作者 Yanli LIU Guangying LU Qin LYU Xiumei LIU jun zheng Xuelian ZHAO Shijun WANG Haijun ZHAO 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2023年第7期650-662,共13页
The syndrome of dampness stagnancy due to spleen deficiency(DSSD)is relatively common globally.Although the pathogenesis of DSSD remains unclear,evidence has suggested that the gut microbiota might play a significant ... The syndrome of dampness stagnancy due to spleen deficiency(DSSD)is relatively common globally.Although the pathogenesis of DSSD remains unclear,evidence has suggested that the gut microbiota might play a significant role.Radix Astragali,used as both medicine and food,exerts the effects of tonifying spleen and qi.Astragalus polysaccharide(APS)comprises a macromolecule substance extracted from the dried root of Radix Astragali,which has many pharmacological functions.However,whether APS mitigates the immune disorders underlying the DSSD syndrome via regulating gut microbiota and the relevant mechanism remains unknown.Here,we used DSSD rats induced by high-fat and low-protein(HFLP)diet plus exhaustive swimming,and found that APS of moderate molecular weight increased the body weight gain and immune organ indexes,decreased the levels of interleukin-1β(IL-1β),IL-6,and endotoxin,and suppressed the Toll-like receptor 4/nuclear factor-κB(TLR4/NF-κB)pathway.Moreover,a total of 27 critical genera were significantly enriched according to the linear discriminant analysis effect size(LEfSe).APS increased the diversity of the gut microbiota and changed its composition,such as reducing the relative abundance of Pseudoflavonifractor and Paraprevotella,and increasing that of Parasutterella,Parabacteroides,Clostridium XIVb,Oscillibacter,Butyricicoccus,and Dorea.APS also elevated the contents of short-chain fatty acids(SCFAs).Furthermore,the correlation analysis indicated that 12 critical bacteria were related to the body weight gain and immune organ indexes.In general,our study demonstrated that APS ameliorated the immune disorders in DSSD rats via modulating their gut microbiota,especially for some bacteria involving immune and inflammatory response and SCFA production,as well as the TLR4/NF-κB pathway.This study provides an insight into the function of APS as a unique potential prebiotic through exerting systemic activities in treating DSSD. 展开更多
关键词 Astragalus polysaccharide Gut microbiota Toll-like receptor 4/nuclear factor-κB(TLR4/NF-κB)pathway Dampness stagnancy due to spleen deficiencyImmune disorder Short-chain fatty acid
原文传递
A universal elliptical disc(UED)model to represent natural rock fractures 被引量:8
20
作者 jun zheng Jichao Guo +3 位作者 Jiongchao Wang Honglei Sun Jianhui Deng Qing Lv 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第2期261-270,共10页
Since natural fractures are often non-equidimensional,the circular disc model still has great limitations.By contrast,the elliptical disc model is more applicable to representing natural fractures,especially for slend... Since natural fractures are often non-equidimensional,the circular disc model still has great limitations.By contrast,the elliptical disc model is more applicable to representing natural fractures,especially for slender ones.This paper developed a universal elliptical disc(UED)model by incorporating the center point,size,and azimuth of fractures as variables.Specifically,with respect to the azimuth of elliptical fractures in three-dimensional(3D)space,we proposed a paradigm to construct its probability density function(PDF)by coupling the orientation and rotation angle of long axis based on three coordinate transformations.To illustrate the construction process of the PDF of the fracture azimuth,we took the orientation following the Fisher distribution and the rotation angle following Von Mises distribution as an example.A rock slope is used to show the use of the developed UED model,and the 3D DFNs for the slope rock mass are generated by Monte Carlo simulation.In addition,the DFNs for the rock mass are also generated based on the existing circular disc model and non-universal elliptical disc model.The comparison results from the three models clearly illustrate the superiority of the UED model over the existing circular and non-universal elliptical disc models. 展开更多
关键词 Discrete fracture networks Rock mass DISCONTINUITY Elliptical disc model Fisher distribution Monte Carlo simulation
在线阅读 下载PDF
上一页 1 2 7 下一页 到第
使用帮助 返回顶部