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Genome-level diversification of eight ancient tea populations in the Guizhou and Yunnan regions identifies candidate genes for core agronomic traits 被引量:9
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作者 litang Lu Hufang Chen +5 位作者 Xiaojing Wang Yichen Zhao Xinzhuan Yao Biao Xiong Yanli Deng Degang Zhao 《Horticulture Research》 SCIE 2021年第1期2559-2568,共10页
The ancient tea plant,as a precious natural resource and source of tea plant genetic diversity,is of great value for studying the evolutionary mechanism,diversification,and domestication of plants.The overall genetic ... The ancient tea plant,as a precious natural resource and source of tea plant genetic diversity,is of great value for studying the evolutionary mechanism,diversification,and domestication of plants.The overall genetic diversity among ancient tea plants and the genetic changes that occurred during natural selection remain poorly understood.Here,we report the genome resequencing of eight different groups consisting of 120 ancient tea plants:six groups from Guizhou Province and two groups from Yunnan Province.Based on the 8,082,370 identified high-quality SNPs,we constructed phylogenetic relationships,assessed population structure,and performed genome-wide association studies(GWAS).Our phylogenetic analysis showed that the 120 ancient tea plants were mainly clustered into three groups and five single branches,which is consistent with the results of principal component analysis(PCA).Ancient tea plants were further divided into seven subpopulations based on genetic structure analysis.Moreover,it was found that the variation in ancient tea plants was not reduced by pressure from the external natural environment or artificial breeding(nonsynonymous/synonymous=1.05).By integrating GWAS,selection signals,and gene function prediction,four candidate genes were significantly associated with three leaf traits,and two candidate genes were significantly associated with plant type.These candidate genes can be used for further functional characterization and genetic improvement of tea plants. 展开更多
关键词 GUIZHOU ANCIENT integrating
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Clinicopathological Features of Nondiabetic Renal Diseases from Different Age Groups:An Observational Cross-sectional Study 被引量:6
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作者 Xiao-Min Liu Qian Wang +8 位作者 Zhe-Yi Dong Wei-Guang Zhang Guang-Yan Cai Li Zhang Yong Wang Han-Yu Zhu litang Wan-Jun Shen Xiang-Mei Chen 《Chinese Medical Journal》 SCIE CAS CSCD 2018年第24期2953-2959,共7页
Background:Diabetes mellitus (DM)has become the leading cause of chronic kidney disease (CKD).Nondiabetic renal diseases (NDRDs) have different clinicopathological features and prognosis from those of diabetic nephrop... Background:Diabetes mellitus (DM)has become the leading cause of chronic kidney disease (CKD).Nondiabetic renal diseases (NDRDs) have different clinicopathological features and prognosis from those of diabetic nephropathy.Our study sought to analyze the clinical and pathological features of NDRDs,in different age groups through a cross-sectional study. Methods:All patients with type 2 DM at our center who underwent renal biopsy between March 1997 and March 2017 were screened and divided into three groups by age:Group 1 (youth group),18-44 years old;Group 2 (middle-aged group),45-59 years old;and Group 3 (elderly group),≥60 years old.We analyzed the clinicopathological data and risk factors by univariate and multivariate logistic regression for NDRD of the patients to identify the features of NDRD in different age groups. Results:We included 982 patients in the final analysis.Patients with NDRD accounted for 64.4%of all patients.IgA nephropathy (IgAN) was the most common pathological pattern in young patients with NDRD,accounting for 26.3%.In the middle-aged group,the two most common pathological patterns were IgAN and membranous nephropathy.Membranous nephropathy was the most common pathological pattern in elderly patients with NDRD,accounting for 29.3%.Consistent with pathological features,glomerular hematuria is a risk factor for NDRD in Group 1 (odds ratio [OR],26.514;95%confidence interval [CI],2.503-280.910;P =0.006).On the other hand,rapidly increasing proteinuria or nephrotic syndrome is a risk factor for NDRD in Group 2 (OR,5.921;95% CI,2.061-17.013;P =0.001)and Group 3 (OR,90.409;95%CI,6.198-1318.826;P =0.001). Conclusions:This single-center study showed that the proportion and composition of NDRD differ among different age groups. Consistent with pathological features,some clinical indices such as hematuria and proteinuria showed different features among different age groups. 展开更多
关键词 Age Nondiabetic RENAL DISEASE TYPE 2 DIABETIC NEPHROPATHY
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A review of integrated surface-subsurface numerical hydrological models
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作者 Lele SHU Hao CHEN +8 位作者 Xianhong MENG Yan CHANG litang HU Wenke WANG Longcang SHU Xuan YU Christopher DUFFY Yingying YAO Donghai ZHENG 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第5期1459-1479,共21页
Hydrological modeling,leveraging mathematical formulations to represent the hydrological cycle,is a pivotal tool in representing the spatiotemporal dynamics and distribution patterns inherent in hydrology.These models... Hydrological modeling,leveraging mathematical formulations to represent the hydrological cycle,is a pivotal tool in representing the spatiotemporal dynamics and distribution patterns inherent in hydrology.These models serve a dual purpose:they validate theoretical robustness and applicability via observational data and project future trends,thereby bridging the understanding and prediction of natural processes.In rapid advancements in computational methodologies and the continuous evolution of observational and experimental techniques,the development of numerical hydrological models based on physicallybased surface-subsurface process coupling have accelerated.Anchored in micro-scale conservation principles and physical equations,these models employ numerical techniques to integrate surface and subsurface hydrodynamics,thus replicating the macro-scale hydrological responses of watersheds.Numerical hydrological models have emerged as a leading and predominant trend in hydrological modeling due to their explicit representation of physical processes,heightened by their spatiotemporal resolution and reliance on interdisciplinary integration.This article focuses on the theoretical foundation of surface-subsurface numerical hydrological models.It includes a comparative and analytical discussion of leading numerical hydrological models,encompassing model architecture,numerical solution strategies,spatial representation,and coupling algorithms.Additionally,this paper contrasts these models with traditional hydrological models,thereby delineating the relative merits,drawbacks,and future directions of numerical hydrological modeling. 展开更多
关键词 Numerical Hydrological Models Surface-Subsurface Process Coupling Numerical Methods Hydrological Modeling
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Predicting the Time-Dependent Toxicities of Binary Mixtures of Five Antibiotics to Vibrio qinghaiensis sp.-Q67 Based on the QSAR Model
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作者 Xiachangli Xu Yongan Liu +3 位作者 Lingyun Mo Xuehua Li Junfeng Dai litang Qin 《Environment & Health》 2024年第7期465-473,共9页
Antibiotics may be exposed in a mixed state in natural environments.The toxicity of antibiotic mixtures exhibits time-dependent characteristics,and data on the time-dependent toxicity of antibiotic mixtures is also re... Antibiotics may be exposed in a mixed state in natural environments.The toxicity of antibiotic mixtures exhibits time-dependent characteristics,and data on the time-dependent toxicity of antibiotic mixtures is also relatively lacking.In this study,the toxicities of 45 binary mixtures composed of five antibiotics were investigated against Vibrio qinghaiensis sp.-Q67(Q67)at multiple exposure times(4,6,8,10,and 12 h).Quantitative structure–activity relationship(QSAR)models were developed for predicting the time-dependent toxicities of 45 binary mixtures.The results showed that the best QSAR models presented coefficient of determination(R2)of(0.818–0.913)and explained variance in prediction leave-one-out(Q2LOO)of(0.781–0.894)and predictive ability(Q2F1,Q2F2,Q2F3>0.682,concordance correlation coefficient>0.859).The R2 values of QSAR models outperformed the R2(0.628–0.810)of the conventional concentration addition models and the R2(0.654–0.792)of the independent action models.Furthermore,the QSAR models showed higher R2 and Q2LOO values at 4 h compared to other exposure times.Specifically,the model at the 30%effective concentration(EC30)had R2 of 0.902 and Q2LOO of 0.883,while the model at the 50%effective concentration(EC50)had R2 of 0.913 and Q2LOO of 0.894.The CATS2D_04_DP descriptor was found to be the most dominant and negatively correlated factor influencing the toxicity of mixed antibiotics against Q67 in the nine QSAR models developed over five exposure times.The reduction in the number of DP pharmacophore point pairs with a topological distance of 4 in the represented molecules is the primary cause for the rise in the time-dependent toxicity of the antibiotics against Q67. 展开更多
关键词 ANTIBIOTICS Q67 QSAR model time-dependent toxicity toxicities prediction
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Genome-Wide Identification of ABCC Gene Subfamily Members and Functional Analysis of CsABCC11 in Camellia sinensis
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作者 Mingyuan Luo Shiyu Tian +7 位作者 Xinzhuan Yao Yue Wan Zhouzhuoer Chen Zifan Yang Huagen Hao Fei Liu Hu Tang litang Lu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第8期2019-2036,共18页
The ATP-binding cassette(ABC)transporter is a gene superfamily in plants.ATP-binding cassette subfamily C(ABCC)protein is a multidrug resistance-associated(MRP)transporter.They play various roles in plant growth,devel... The ATP-binding cassette(ABC)transporter is a gene superfamily in plants.ATP-binding cassette subfamily C(ABCC)protein is a multidrug resistance-associated(MRP)transporter.They play various roles in plant growth,development,and secondary metabolite transport.However,there are few studies on ABCC transporters in tea plants.In this study,genome-wide association study(GWAS)analysis of epigallocatechin gallate(EGCG)content in 108 strains of Kingbird revealed that CsABCCs may be involved in EGCG transport.We identified 25 CsABCC genes at the genomic level of the tea plant,their phylogenetic tree,gene structure,targeted miRNA and other bioinformatics were analyzed.The expression patterns of CsABCCs in eight different tissues and abiotic stress indicate that they have potential roles in regulating the growth,development,and defense of tea plants.The correlation analysis revealed that the expression of the CsABCC11 gene was closely related to the EGCG content in tea buds of 108 strains of the Kingbird,and the subcellular localization experiments in tobacco showed that CsABCC11 protein was localized on the plasma membrane.The virus-induced gene silencing(VIGS)strategy in tea plants further verified that CsABCC11 was involved in EGCG accumulation.Our study laid a foundation for studying the biological function of CsABCC and provided a new candidate molecular marker gene for further EGCG-related variety breeding,which will be of great interest to breeders. 展开更多
关键词 Camellia sinensis ABCC gene subfamily EGCG VIGS guizhou local variety Kingbird
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The transcription factor CsS40 negatively regulates TCS1 expression and caffeine biosynthesis in connection to leaf senescence in Camellia sinensis 被引量:2
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作者 Xinzhuan Yao Hufang Chen +8 位作者 Antao Ai Fen Wang Shanshan Lian Hu Tang Yihe Jiang Yujie Jiao Yumei He Tong Li litang Lu 《Horticulture Research》 SCIE CSCD 2023年第9期194-206,共13页
Caffeine is considered as one of the most important bioactive components in the popular plant beverages tea,cacao,and coffee,but as a wide-spread plant secondary metabolite its biosynthetic regulation at transcription... Caffeine is considered as one of the most important bioactive components in the popular plant beverages tea,cacao,and coffee,but as a wide-spread plant secondary metabolite its biosynthetic regulation at transcription level remains largely unclear.Here,we report a novel transcription factor Camellia sinensis Senescnece 40(CsS40)as a caffeine biosynthesis regulator,which was discovered during screening a yeast expression library constructed from tea leaf cDNAs for activation of tea caffeine synthase(TCS1)promoter.Besides multiple hits of the non-self-activation CsS40 clones that bound to and activated TCS1 promoter in yeast-one-hybrid assays,a split-luciferase complementation assay demonstrated that CsS40 acts as a transcription factor to activate the CsTCS1 gene and EMSA assay also demonstrated that CsS40 bound to the TCS1 gene promoter.Consistently,immunofluorescence data indicated that CsS40-GFP fusion was localized in the nuclei of tobacco epidermal cells.The expression pattern of CsS40 in‘Fuding Dabai’developing leaves was opposite to that of TCS1;and knockdown and overexpression of CsS40 in tea leaf calli significantly increased and decreased TCS1 expression levels,respectively.The expression levels of CsS40 were also negatively correlated to caffeine accumulation in developing leaves and transgenic calli of‘Fuding Dabai’.Furthermore,overexpression of CsS40 reduced the accumulation of xanthine and hypoxanthine in tobacco plants,meanwhile,increased their susceptibility to aging.CsS40 expression in tea leaves was also induced by senescence-promoting hormones and environmental factors.Taken together,we showed that a novel senescence-related factor CsS40 negatively regulates TCS1 and represses caffeine accumulation in tea cultivar‘Fuding Dabai’.The study provides new insights into caffeine biosynthesis regulation by a plant-specific senescence regulator in tea plants in connection to leaf senescence and hormone signaling. 展开更多
关键词 S40 CAFFEINE TCS
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Population Structure Analysis and Genome-Wide Association Study of Tea(Camellia sinensis(L.)Kuntze)Germplasm in Qiannan,China,Based on SLAF-Seq Technology 被引量:2
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作者 Fen Zhang Weili Tian +5 位作者 Lu Cen litang Lv Xiaofang Zeng Yulu Chen Yichen Zhao Yan Li 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第4期791-809,共19页
Duyun Maojian tea is a famous tea in China.In this study,the specific-locus amplified fragment(SLAF)sequencing method was used to analyze the population structure and conduct a genome-wide association study(GWAS)of 2 ... Duyun Maojian tea is a famous tea in China.In this study,the specific-locus amplified fragment(SLAF)sequencing method was used to analyze the population structure and conduct a genome-wide association study(GWAS)of 2 leaf traits of 123 tea plants in Qiannan,China.A total of 462,019 SLAF tags and 11,362,041 single-nucleotide polymorphism(SNP)loci were obtained.The results of phylogenetic tree analysis,cluster analysis,and principal component analysis showed that 123 tea germplasms were clustered into three groups,and the heterozygosity rates for Groups I,II,and II were 0.206,0.224,and 0.34,respectively.Generally,tea germplasms in a production area are clustered in a group,indicating that tea germplasms in different production areas have certain genetic diversity.The traditional Duyun Maojian tea core production areas,TS and DC-SJ,are clustered into Group I and Group II respectively,while the ZY production area is relatively independent in Group III.Furthermore,based on GWAS analysis,11 candidate genes related to leaf apex and 7 candidate genes related to leaf shape were obtained.This study clarified the genetic relationship among eight Duyun Maojian tea production areas and obtained candidate genes related to leaf apex and leaf shape development.The results showed that population structure and candidate genes are an effective basis for the breeding of Duyun Maojian tea germplasm. 展开更多
关键词 Duyun maojian tea plant SLAF-seq SNP genetic structure leaf character GWAS
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Genome-Wide Characterization of the Cellulose Synthase Gene Superfamily in Tea Plants(Camellia sinensis)
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作者 Qianqian Li Qi Zhao +2 位作者 Xinzhuan Yao Baohui Zhang litang Lu 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第10期2163-2189,共27页
The cellulose synthase gene superfamily,including Cellulose synthase A(CesA)and cellulose synthase-like(Csl)gene families,is responsible for the synthesis of cellulose and hemicellulose,respectively.The CesA/Csl genes... The cellulose synthase gene superfamily,including Cellulose synthase A(CesA)and cellulose synthase-like(Csl)gene families,is responsible for the synthesis of cellulose and hemicellulose,respectively.The CesA/Csl genes are vital for abiotic stress resistance and shoot tenderness regulation of tea plants(Camellia sinensis).However,the CesA/Csl gene family has not been extensively studied in tea plants.Here,we identified 53 CsCesA/Csl genes in tea plants.These genes were grouped into five subfamilies(CsCesA,CsCslB,CsCslD,CsCslE,CsCslG)based on the phylogenetic relationships with Arabidopsis and rice.The analysis of chromosome distribution,gene structure,protein domain and motif revealed that most genes in CsCesA,CsCslD and CsCslE subfamilies were conserved,whereas CsCslB and CsCslG subfamily members are highly diverged.The transcriptome analysis showed that most CsCesA/Csl genes displayed tissue-specific expression pattern.In addition,members of CsCslB4,CsCesA1/3/6,CsCslB3/4,CsCslD3,CsCslE1 and CsCslG2/3 subfamilies were up-regulated under drought and cold stresses,indicating their potential roles in regulating stress tolerance in tea plants.Furthermore,the expression levels of CsCslG2_6 and CsCslD3_5 in different tissues and cultivars,respectively,were positively correlated with the cellulose content that is negatively related with shoot tenderness.Thus,these two genes were speculated to be involved in the regulation of shoot tenderness in tea plants.Our findings may help elucidate the evolutionary relationships and expression patterns of the CsCesA/Csl genes in tea plants,and provide more candidate genes responsible for stress tolerance and tenderness regulation in tea plants for future functional research. 展开更多
关键词 Tea plant(Camellia sinensis) cellulose synthase superfamily PHYLOGENY stress resistance shoot tenderness regulation
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Chemical components in yellow mealworm(Tenebrio molitor L.)reared with tea powder
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作者 Yanxia Wang Hongya Li +3 位作者 Yu Lu Wenyi He Chen Wang litang 《Journal of Future Foods》 2022年第3期266-269,共4页
The yellow mealworms(Tenebrio molitor L.)were reared by different ratios of tea powder and wheat bran powder mixtures,and weighted every day during the whole 10 days rearing.The content of tea polyphenols,total catech... The yellow mealworms(Tenebrio molitor L.)were reared by different ratios of tea powder and wheat bran powder mixtures,and weighted every day during the whole 10 days rearing.The content of tea polyphenols,total catechins,catechin(C),epicatechins(EC),epigallocatechins(EGC),epicatechin gallates(ECG),epigallocatechin gallates(EGCG),and nutrition components such as protein and fatty acid in the yellow mealworms were determined after 10 days rearing.The yellow mealworms can put on weight and grow well when the proportion of tea powder belows 80%,while 100%tea powder rearing has no signifi cantly reduced the weight of yellow mealworms.The content of tea polyphenols,total catechins,C,EC,EGC,ECG,and EGCG all enhance signifi cantly along with the increase ratio of the tea powder.The protein content increase more signifi cantly at 50%and 80%ratios treatments than the other treatments.Tea powder added rearing reduces the content of saturated fatty acid,and has a complex effect on the content of unsaturated fatty acid.Comprehensive analysis of the components determined show that 50%ratio is the best for yellow mealworm rearing. 展开更多
关键词 Yellow mealworm TEA PROTEIN Fatty acid
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The Development of Transportation in Wuhan
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作者 WU HEHUANG GU litang 《China Today》 1995年第10期21-22,46,共3页
TheDevelopmentofTransportationinWuhanByWUHEHUANG&GULITANGWUHANISsituatedonthemiddlereachesoftheYangtzeRiver,... TheDevelopmentofTransportationinWuhanByWUHEHUANG&GULITANGWUHANISsituatedonthemiddlereachesoftheYangtzeRiver,rightwhereChina's... 展开更多
关键词 The Development of Transportation in Wuhan
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永定河生态补水的地下水位动态响应 被引量:33
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作者 胡立堂 郭建丽 +2 位作者 张寿全 孙康宁 杨郑秋 《水文地质工程地质》 CAS CSCD 北大核心 2020年第5期5-11,共7页
永定河流域生态修复是京津冀协同发展的重要议题,地下水位对生态补水动态响应的研究是关键的科学问题。以2020年春季永定河生态补水实践为研究基础,采用地下水均衡分析、相关分析和聚类分析等多种技术手段,详细讨论了不同河段河道渗漏... 永定河流域生态修复是京津冀协同发展的重要议题,地下水位对生态补水动态响应的研究是关键的科学问题。以2020年春季永定河生态补水实践为研究基础,采用地下水均衡分析、相关分析和聚类分析等多种技术手段,详细讨论了不同河段河道渗漏损失、地下水动态变化与控制因素。研究发现,2020年春季大流量生态补水河道的渗漏损失率(20%~40%)比2016年(30%~60%)和2019年(41%~58%)的小流量生态补水低;生态补水条件下,77眼观测井地下水动态呈现显著回升、变化不显著和持续下降三种变化规律;根据影响因素划定了河道渗漏补给主控型、河道渗漏和降水主控型、河道渗漏-降水-地下水开采作用明显型、河道渗漏-降水-地下水开采作用不明显型4种类型。其中,河道渗漏主控型的监测井在补水期的地下水位迅速升高,升幅一般在1~19 m之间,最大达20 m,而且存在明显的滞后性。这些规律可为制定科学的生态补水方案提供技术参考。 展开更多
关键词 生态补水 永定河 地下水动态 聚类分析 滞后性
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钒钛磁铁矿提钒技术研究现状与展望 被引量:25
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作者 常福增 赵备备 +2 位作者 李兰杰 耿立唐 张振全 《钢铁钒钛》 CAS 北大核心 2018年第5期71-78,共8页
系统阐述了钒钛磁铁矿提钒过程,主要介绍了直接提钒、钒渣提钒、钢渣提钒的方法,分析讨论了各种方法的优缺点,并对提钒新技术进行了探讨,最后指出:钒渣钙法提钒、亚熔盐清洁提钒、硫酸法钒铬共提是今后研究的重点;氯化法制备高纯氧化钒... 系统阐述了钒钛磁铁矿提钒过程,主要介绍了直接提钒、钒渣提钒、钢渣提钒的方法,分析讨论了各种方法的优缺点,并对提钒新技术进行了探讨,最后指出:钒渣钙法提钒、亚熔盐清洁提钒、硫酸法钒铬共提是今后研究的重点;氯化法制备高纯氧化钒技术因流程短、过程清洁、产品纯度高,具有良好的应用前景;寻求短流程、规模化、低成本、收率高、无污染的清洁提钒工艺将是未来钒钛磁铁矿提钒的发展方向。 展开更多
关键词 钒钛磁铁矿 直接提钒 钒渣提钒 钢渣提钒 高纯五氧化二钒
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地下水污染源识别的数学方法研究进展 被引量:23
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作者 王景瑞 胡立堂 《水科学进展》 EI CAS CSCD 北大核心 2017年第6期943-952,共10页
地下水污染源识别模型可利用有限的观测资料估计污染源位置、污染物泄露强度及其泄露过程,是制定地下水污染修复方案的依据。在阐明地下水污染源识别基本问题基础上,综述了污染源识别研究的两大类数学方法,一类为直接方法,包括反向追踪... 地下水污染源识别模型可利用有限的观测资料估计污染源位置、污染物泄露强度及其泄露过程,是制定地下水污染修复方案的依据。在阐明地下水污染源识别基本问题基础上,综述了污染源识别研究的两大类数学方法,一类为直接方法,包括反向追踪法和基于正则化的方法;另一类为间接方法,包括基于优化的方法和基于概率统计的方法。同时指出了当前污染源识别数学方法应用中存在的主要问题:地下水污染源识别问题的复杂性、地下水有机污染问题和模型求解效率的低下性。对土壤-地下水的联合管理、基于物联网的地下水污染监测、对非水相流体(Non-aqueous Phase Liquid,NAPL)类污染源识别以及基于图形处理器(GPU)的异构并行计算将是未来研究的重点方向。 展开更多
关键词 地下水污染源识别 非适定性 优化算法 贝叶斯推理 非水相流体
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中华茶文化的源流、概念界定与主要特质 被引量:18
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作者 刘礼堂 宋时磊 《农业考古》 2020年第5期7-13,共7页
根据二重证据法,中国人开发利用茶叶的信史,目前可追溯至西汉;茶作为一种成熟的文化图景,出现于唐代;茶文化作为一种概念被广泛使用,则始自20世纪80年代以后,与中华文化的复兴大潮一致。本文梳理了众说纷纭的茶文化概念,厘清其边界和内... 根据二重证据法,中国人开发利用茶叶的信史,目前可追溯至西汉;茶作为一种成熟的文化图景,出现于唐代;茶文化作为一种概念被广泛使用,则始自20世纪80年代以后,与中华文化的复兴大潮一致。本文梳理了众说纷纭的茶文化概念,厘清其边界和内涵,重申了茶文化的人文科学属性,并界定了其涵盖包括思想哲理(茶道)、茶艺、茶文学、茶功用、茶俗、茶礼、茶馆、茶具等方面及其中所体现的发展史等方面的基本内容。在此基础上,分析了中华茶文化历史传承的悠久性、统一而多元的整体性、生产和消费的区域性、发展的时代性、传播的国际性等五个方面的主要特质。 展开更多
关键词 茶文化 概念史 文化特质 中华文化
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医耗联动综合改革对某三级综合医院医保患者住院费用的影响分析 被引量:15
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作者 聂广孟 张燕 +2 位作者 李天烨 潘艳飞 张文砚 《中国医院》 北大核心 2021年第3期9-11,共3页
目的:探讨北京市医耗联动综合改革对三级综合医院医保患者住院费用的影响。方法:采用回顾性横断面研究,通过医保组件系统检索医耗联动综合改革前后北京市某市属综合医院医保患者住院费用数据。运用t检验对改革前后医保患者例均住院费用... 目的:探讨北京市医耗联动综合改革对三级综合医院医保患者住院费用的影响。方法:采用回顾性横断面研究,通过医保组件系统检索医耗联动综合改革前后北京市某市属综合医院医保患者住院费用数据。运用t检验对改革前后医保患者例均住院费用、费用结构和患者个人负担等指标进行对比。结果:改革后,医保患者例均住院费用下降3.27%;例均药费下降11.25%,例均耗材费用下降3.56%,例均检查化验费降低2.47%;例均手术治疗费用增长11.69%;例均自费费用下降33.10%,医保患者个人负担下降9.72%。结论:北京市医耗联动综合改革政策的实施降低了医保患者个人负担,住院费用结构进一步优化,医疗服务价格趋向更加合理。医院需加强内部管理,政府应从价格调整和政府补偿角度进一步巩固改革成果。 展开更多
关键词 医耗联动 综合改革 医保费用 住院费用
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固相萃取-超高效液相色谱-串联质谱法测定水中16种有机磷农药残留 被引量:13
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作者 高振刚 曾莎莎 +3 位作者 曾鸿鹄 梁延鹏 覃礼堂 宋晓红 《分析科学学报》 CAS CSCD 北大核心 2021年第1期22-28,共7页
本研究建立了固相萃取-超高效液相色谱-串联质谱(SPE-UPLC-MS/MS)测定水中16种有机磷农药残留的分析方法。考察了C18柱和HLB柱分别串联活性炭AC固相萃取柱的萃取效果,以及单一和混合溶剂的洗脱效果。水样用0.45μm滤膜过滤后用HCl调节pH... 本研究建立了固相萃取-超高效液相色谱-串联质谱(SPE-UPLC-MS/MS)测定水中16种有机磷农药残留的分析方法。考察了C18柱和HLB柱分别串联活性炭AC固相萃取柱的萃取效果,以及单一和混合溶剂的洗脱效果。水样用0.45μm滤膜过滤后用HCl调节pH至4,经HLB-活性炭AC串联小柱富集净化后,分别用丙酮-二氯甲烷(4∶1,V/V)和5 mmol/L NH 4Ac甲醇溶液洗脱HLB小柱和活性炭AC小柱,洗脱液混合氮吹复溶,定容后采用外标法定量分析。在最佳测试条件下,16种目标物在1~100μg/L范围内呈现良好的线性关系,相关系数(R 2)均大于0.991,检出限为0.004~0.238 ng/L;平均回收率在55.5%~109.7%之间,相对标准偏差(RSD)为2.0%~13.9%。该方法灵敏度较高,重复性好,适用于水中16种有机磷农药残留检测。 展开更多
关键词 固相萃取 超高效液相色谱-串联质谱 有机磷农药
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布地奈德联用孟鲁司特钠治疗小儿咳嗽变异性哮喘的临床研究 被引量:13
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作者 余瑞生 邓丽堂 黄志晗 《当代医学》 2021年第3期82-83,共2页
目的探讨布地奈德联用孟鲁司特钠治疗小儿咳嗽变异性哮喘的临床效果。方法选取2017年11月至2019年2月于本院就诊的小儿咳嗽变异性哮喘患儿65例,按随机数表法分为对照组(n=32)和观察组(n=33)。对照组给予布地奈德治疗,观察组给予布地奈... 目的探讨布地奈德联用孟鲁司特钠治疗小儿咳嗽变异性哮喘的临床效果。方法选取2017年11月至2019年2月于本院就诊的小儿咳嗽变异性哮喘患儿65例,按随机数表法分为对照组(n=32)和观察组(n=33)。对照组给予布地奈德治疗,观察组给予布地奈德联用孟鲁司特钠治疗,比较两组肺功能及临床症状积分。结果治疗后,观察组患儿PEF、FEV1、FVC、FEV1/FVC均高于对照组,症状积分低于对照组,差异有统计学意义(P<0.05)。结论布地奈德联用孟鲁司特钠治疗小儿咳嗽变异性哮喘可有效改善患者肺功能及临床症状,具有较高的临床应用价值。 展开更多
关键词 布地奈德 孟鲁司特钠 小儿咳嗽变异性哮喘 肺功能
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四川省鼠疫耶尔森菌CRISPR基因分型及地区分布研究 被引量:10
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作者 祁腾 梁莹 +14 位作者 李伟 杨军 罗隆泽 段风刚 汪立茂 李帆 金忠强 谭文明 谢飞 王宏 刀吉 刘建 曾林子 廖虹瑜 雷高鹏 《中国人兽共患病学报》 CAS CSCD 北大核心 2018年第9期801-804,810,共5页
目的对四川省鼠疫耶尔森菌(Yersinia pestis)做规律成簇的间隔短回文重复序列(Clustered regularly interspaced short palindromic repeats CRSIPR)基因分型和地区分布研究,为四川鼠疫防治提供科学依据。方法对132株鼠疫菌培养和提取核... 目的对四川省鼠疫耶尔森菌(Yersinia pestis)做规律成簇的间隔短回文重复序列(Clustered regularly interspaced short palindromic repeats CRSIPR)基因分型和地区分布研究,为四川鼠疫防治提供科学依据。方法对132株鼠疫菌培养和提取核酸,应用3对CRISPR引物对被试菌株DNA进行PCR扩增、测序和分析,确定四川省鼠疫菌的CRSIPR基因型。结果 132株鼠疫菌共发现17种spacer,包括YPa 9种、YPb 5种、YPc 3种,新发现的1种space阵列。所有鼠疫菌株被分为2个CRISPR基因簇(Cc3′,Ca7),3个基因型(37′型、22型和sc01型)。其中石渠县青海田鼠型菌株基因型为37′型,石渠县人间鼠疫的菌株为22型,德格县旱獭型菌株基因型为22型,巴塘县、理塘县、雅江县和新龙县旱獭菌株基因型为sc01型。结论四川省鼠疫菌菌株具有明显的地区分布特征。 展开更多
关键词 鼠疫 四川省 CRISPR 分子分型
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固相萃取-超高效液相色谱-三重四极杆质谱法测定水中15种抗生素残留 被引量:13
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作者 高振刚 梁延鹏 +1 位作者 曾鸿鹄 覃礼堂 《分析试验室》 CAS CSCD 北大核心 2021年第8期875-880,共6页
建立了固相萃取-超高效液相色谱-三重四极杆串联质谱(SPE-UPLC-MS/MS)测定水中磺胺类、喹诺酮类及四环素类抗生素的分析方法。考察了滤膜、固相萃取柱、洗脱液种类和体积、pH、上样流速对萃取效果的影响。水样过滤后调节至pH 3,经HLB小... 建立了固相萃取-超高效液相色谱-三重四极杆串联质谱(SPE-UPLC-MS/MS)测定水中磺胺类、喹诺酮类及四环素类抗生素的分析方法。考察了滤膜、固相萃取柱、洗脱液种类和体积、pH、上样流速对萃取效果的影响。水样过滤后调节至pH 3,经HLB小柱富集净化后,依次用0.1%(V:V)甲酸甲醇和3%(V:V)氨水甲醇洗脱,采用外标法定量分析。15种目标化合物在1~200μg/L范围内线性关系良好,检出限为0.15~1.04 ng/L;平均回收率在81.2%~116.6%之间,相对标准偏差(RSDs)为0.6%~8.9%。该方法适用于水中15种抗生素残留检测。 展开更多
关键词 固相萃取 超高效液相色谱-三重四极杆串联质谱 抗生素
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贸易政策不确定性对我国出口升级的影响研究 被引量:12
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作者 李宏兵 孙丽棠 文磊 《经济经纬》 CSSCI 北大核心 2022年第2期57-67,共11页
作为全球最重要的双边关系之一,中美经贸摩擦及其引致的贸易政策不确定性,引发了对中国出口转型升级的担忧。利用2000—2013年企业-产品层面微观数据和1999—2019年行业层面数据,通过双重差分模型识别了贸易政策不确定性对我国制造业出... 作为全球最重要的双边关系之一,中美经贸摩擦及其引致的贸易政策不确定性,引发了对中国出口转型升级的担忧。利用2000—2013年企业-产品层面微观数据和1999—2019年行业层面数据,通过双重差分模型识别了贸易政策不确定性对我国制造业出口升级的影响效应。研究表明,贸易政策不确定性下降显著促进了以出口技术复杂度衡量的企业出口升级,且对沿海地区企业、中小微型企业、非国有企业的出口技术复杂度有正向促进作用。基于影响机制的研究发现,贸易政策不确定性下降可通过鼓励企业创新和缓解融资约束来提升出口技术复杂度。进一步地,贸易政策不确定性下降还可以通过下游产业关联显著促进本产业出口技术复杂度的上升,对于劳动、资本密集型行业及高、低市场集中度行业均是如此。但对于高市场集中度行业,贸易政策不确定性下降会通过上游产业关联抑制出口技术复杂度的提升,对低市场集中度行业的影响则与之相反。 展开更多
关键词 贸易政策不确定性 出口技术复杂度 双重差分 融资约束 产业关联
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