检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

白背枫的化学成分和药理活性研究

化工管理 2024年第26期 58-62页

作者：宁锦华朱姝张蝶侯安国周紫婧云南中医药大学中药学院云南昆明650500 云南中医药大学第二临床医学院云南昆明650500

白背枫(Buddleja asiatica Lour)为马钱科醉鱼草属植物,原植物为亚洲醉鱼草,全株有毒,民间用来毒鱼,同时还是一种具有杀虫作用的观光型植物。白背枫的根、茎叶具有祛风化湿,行气活血等功效。目前,有关白背枫的研究主要集中在生态修复功... 详细信息

白背枫(Buddleja asiatica Lour)为马钱科醉鱼草属植物,原植物为亚洲醉鱼草,全株有毒,民间用来毒鱼,同时还是一种具有杀虫作用的观光型植物。白背枫的根、茎叶具有祛风化湿,行气活血等功效。目前,有关白背枫的研究主要集中在生态修复功能、园林应用、扦插繁殖和生药鉴别等领域。而与之香气成分的醉鱼功效及药用价值相关的化学成分研究并不深入,国内外仅有少量文献报道。文章根据已发表文献,对白背枫的化学成分和药理活性研究进行综述,以期为白背枫后续研究提供借鉴。

关键词：白背枫化学成分药理活性生物医药医药化工

Effects of Nitric Oxide and Exogenous Ethylene Treatments on Ethylene Biosynthesis in Feicheng Peach

在线全文

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2007年第3期6卷 290-295页

作者： LIU Meng-chen SONG Wei-hong zhu shu-hua ZHOU Jie College of Horticulture Shandong Agricultural University Taian 271018 P.R.China College of Chemistry and Material Science Shandong Agricultural University Taian 271018 P.R.China

The effects of nitric oxide （NO） and exogenous ethylene on ethylene biosynthesis in harvested Feicheng peaches were studied. The antagonistic actions between NO and exogenous ethylene was also investigated. The Feicheng peaches were fumigated with 10μL L^-1 NO, 1 000 μL L^-1 ethylene, or 10 μL L^-1 NO plus 1 000 μL L^-1 ethylene for 3 h. The results suggested that application of exogenous ethylene promoted the biosynthesis of endogenous ethylene in peach fruit. The treatment with NO remarkably inhibited the biosynthesis of ethylene by significantly reducing the activities of ACC synthase （ACS） and ACC oxidase （ACO）. Ethylene biosynthesis in the fruits treated with both NO and exogenous ethylene was lower than that in fruits treated with exogenous ethylene alone but higher than that in fruits treated with NO alone, suggesting that there were antagonistic actions between NO and exogenous ethylene. NO could inhibit the biosynthesis of ethylene and the catalysis of exogenous ethylene during ethylene biosynthesis in peach fruits.

关键词： biosynthesis peach (Prunus persica) ethylene nitric oxide

贵州省一起产气荚膜梭菌引起食源性疾病暴发事件的调查及病原体溯源

在线全文

学校读者我要写书评

暂无评论

中国食品卫生杂志 2024年第5期36卷 557-563页

作者：张莉代华简洁黄靖宇蒋家俊周亚娟田继贵朱姝廖春李军李薇薇郭华贵州医科大学公共卫生与健康学院劳动卫生与环境卫生学系贵州贵阳550025 贵州省疾病预防控制中心贵州贵阳550004 国家食品安全风险评估中心北京100022 贵阳市疾病预防控制中心贵州贵阳550000

目的对贵阳市某学校由产气荚膜梭菌引起发的食源性疾病暴发事件开展流行病学调查和病因食品和病原的溯源分析,探讨全基因组测序新技术在食源性疾病暴发溯源中的应用。方法采用现场流行病学分析,采集可疑生物样本,食品样本和外环境样本... 详细信息

目的对贵阳市某学校由产气荚膜梭菌引起发的食源性疾病暴发事件开展流行病学调查和病因食品和病原的溯源分析,探讨全基因组测序新技术在食源性疾病暴发溯源中的应用。方法采用现场流行病学分析,采集可疑生物样本,食品样本和外环境样本进行常规的实验室病原分离及沙门菌、致泻大肠埃希菌、金黄色葡萄球菌、蜡样芽胞杆菌和产气荚膜梭菌的病原鉴定。对分离的病原菌进行毒素基因检测和全基因组测序溯源分析。结果22名病例症状以腹痛(95.45%,21/22)、腹泻(95.45%,21/22)为主;流行曲线为点源暴露模式,潜伏期为6-15 h。在5份肛拭子样本、3份粪便样本和1份留样早餐肉末食品样本中分离出产气荚膜梭菌,且均检出肠毒素cpe基因,所有样本均未检出沙门菌、致泻大肠埃希菌、金黄色葡萄球菌和蜡样芽胞杆菌。其中早餐肉末食品样品中经全基因组测序分析对比发现产气荚膜梭菌为3.5×10^(5) CFU/g,经全基因组测序分析比对发现,来源于早餐肉末食品和肛拭子样本的产气荚膜梭菌,其分子分型为ST139型,菌株均携带cpe毒力基因。结论通过现场调查和溯源分析,判定产气荚膜梭菌污染早餐肉末是导致此次食源性疾病暴发的原因。全基因组测序新技术在食源性疾病暴发中可起到精准溯源作用。

关键词：产气荚膜梭菌食源性疾病暴发事件毒素基因溯源分析食源性致病菌

在线全文

学校读者我要写书评

暂无评论

泡沫夹芯板四点弯曲力学性能研究

航空精密制造技术 2024年第5期60卷 1-4页

作者：徐志胜朱书华杨发建胡元杰辛尊南京航空航天大学南京模拟技术研究所

为研究泡沫夹芯板在弯曲载荷下的力学响应和损伤模式，本文对碳纤织物泡沫夹芯板进行了四点弯曲试验，并结合Abaqus软件建立了夹芯板四点弯曲的三维有限元模型进行分析，结果发现泡沫夹芯板的主要损伤模式为基体/纤维压缩破坏，与实验... 详细信息

为研究泡沫夹芯板在弯曲载荷下的力学响应和损伤模式，本文对碳纤织物泡沫夹芯板进行了四点弯曲试验，并结合Abaqus软件建立了夹芯板四点弯曲的三维有限元模型进行分析，结果发现泡沫夹芯板的主要损伤模式为基体/纤维压缩破坏，与实验保持一致。最后通过仿真，对比分析了不同泡沫厚度和材料强度的泡沫夹芯板的弯曲性能的影响。结果表明，泡沫厚度越大，泡沫强度越高，夹芯板整体刚度越高，抗弯能力也越强。

关键词：泡沫夹芯板四点弯曲复合材料有限元

A condition-based maintenance policy for reconfigurable multi-device systems

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Advances in Manufacturing 2024年第2期12卷 252-269页

作者： shu-Lian Xie Feng Xue Wei-Min Zhang Jia-Wei zhu School of Mechanical Engineering Tongji UniversityShanghai201804People’s Republic of China

The exploration of component states for optimizing maintenance schedules in complex systems has garnered significant interest from ***,current literature usually overlooks the critical aspects of system flexibility and *** implementation of system reconfiguration can effectively mitigate system downtime and enhance production *** study proposes a dynamic condition-based maintenance policy considering reconfiguration for reconfigurable systems.A double-layer decision rule was constructed for the devices and *** achieve the best overall maintenance effect of the system,the remaining useful life probability distribution and recommended maintenance time of each device were used to optimize the concurrent maintenance time window of the devices and determine whether to reconfigure them.A comprehensive maintenance efficiency index was introduced that simultaneously considered the maintenance cost rate,reliability,and availability of the system to characterize the overall maintenance *** reconfiguration cost was included in the maintenance *** proposed policy was tested through numerical experiments and compared with different-level *** results show that the proposed policy can significantly reduce the downtime and maintenance costs and improve the overall system reliability and availability.

关键词： Condition-based maintenance(CBM) Reconfigurable system Remaining useful life Maintenance cost System reliability

Microbial PAH-Degradation in Soil: Degradation Pathways and Contributing Factors

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pedosphere 2006年第5期16卷 555-565页

作者： ZHANG Xu-Xiang CHENG shu-Pei zhu Cheng-Jun SUN Shi-Lei State Key Laboratory of Pollution Control and Resource Reuse of China Department of Environmental Sciences Nanjing University Nanjing 210093 （China）

Adverse effects on the environment and high persistence in the microbial degradation and environmental fate of polycyclic aromatic hydrocarbons (PAHs) are motivating interest. Many soil microorganisms can degrade PAHs and use various metabolic pathways to do so. However, both the physio-chemical characteristics of compounds as well as the physical, chemical, and biological properties of soils can drastically influence the degradation capacity of naturally occurring microorganisms for field bioremediation. Modern biological techniques have been widely used to promote the efficiency of microbial PAH-degradation and make the biodegradation metabolic pathways more clear. In this review microbial degradation of PAHs in soil is discussed, with emphasis placed on the main degradation pathways and the environmental factors affecting biodegradation.

关键词： bioremediation microbial degradation PAHs soil

Enhancing Molecular Chain Entanglement and π-π Stacking Toward the Improvement of Shape Memory Performance of Polyimide

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2023年第8期41卷 1261-1268,I0009页

作者： Jia-Qiang Li Wen-shuang Li Wen-Ting Zhang shu zhu Chu-Yang Luo Wan-shuang Liu Li-Ying Zhang Shanghai Collaborative Innovation Center of High Performance Fibers and Composite(Province-Ministry Joint) Center for Civil Aviation CompositesDonghua UniversityShanghai 201620China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Shanghai Donghua Composites Technology Co.Ltd. Shanghai 201620China Key Laboratory of Textile Science&Technology College of TextilesDonghua UniversityShanghai 201620China

Thermoplastic polyimides(PIs)with shape memory potential have received growing attention in recent *** this work,highperformance thermoplastic PIs were fabricated by introducing PIs with chain rigidity(r-PI)into PI with chain flexibility(f-PI).The influences of molecular chain entanglement andπ-πinteractions on their thermomechanical and shape memory properties were *** degree of molecular chain entanglement was quantitively characterized based on dynamic mechanical analysis(DMA).Theπ-πinteractions were investigated in detail by X-ray diffraction(XRD)and UV-Vis *** was found that the entanglement density increased andπ-πinteractions became stronger with the introduction of r-PI into f-PI,leading to the improvement of shape ***,a broad and increased glass transition temperature(T_(g))was achieved,endowing the PIs with multiple shape memory *** synergistic effects of increased entanglement density and enhancedπ-πinteractions were beneficial to regulating interchain interactions and thereby achieving high shape memory performance of the PIs.

关键词： Shape memory polyimide Molecular chain entanglement r-r Stacking

Effects of sargentgloryvine stem extracts on HepG-2 cellsin vitro andin vivo

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2011年第23期17卷 2848-2854页

作者： Ming-Hua Wang Min Long Bao-Yi zhu shu-Hui Yang Ji-Hong Ren Hui-Zhong Zhang Department of LaboratoryMedicine and Research Center Tangdu Hospital Fourth MilitaryMedical University Xi＇an 710038 Shaanxi Province China

AIM:To observe the effects of sargentgloryvine stem extracts (SSE) on the hepatoma cell line HepG-2 in vitro andin vivo and determine its mechanisms of ***:Cultured HepG-2 cells treated with SSE were analysed by 3-(4,5-Dimethyl-thiazol-2-yl)-2,5Diphenyltetrazolium bromide and clone formation *** cell cycle and apoptosis analysis were conducted by flow cytometric,TdT-Mediated dUTP Nick End Labeling and acridine orange/ethidium bromide staining methods,and protein expression was examined by both reverse transcriptase-polymerase chain reaction and Western *** pathological changes of the tumor cells were observed by haematoxylin and eosin *** growth inhibition and side effects were determined in a xenograft mouse ***:SSE treatment could not only inhibit HepG-2 cell proliferation in a doseand time-dependent manner but also induce apoptosis and cell cycle arrest at the S *** number of colonies formed by SSEtreated tumor cells was fewer than that of the controls (P0.05).Systemic administration of SSE could inhibit the HepG-2 xenograft tumor growth with no obvious toxic side effects on normal ***:SSE can induce apoptosis of HepG-2 cells in vitro and in vivo through decreasing expression of Bcl-xl and Mcl-1 and increasing expression of Bax.

关键词： Sargentgloryvine stem extract Apoptosis Human hepatocellular carcinoma HepG-2 Bcl-2 family

RL3(t),Responsible for Leaf Shape Formation,Delimited to a 46-kb DNA Fragment in Rice

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rice science 2015年第1期22卷 44-48页

作者： GUO Min LI Rong-de YAO Jian zhu Juan FAN Xiang-yun WANG Wei TANG shu-zhu GU Ming-hong YAN Chang-jie Jiangsu Key Laboratory of Crop Genetics and Physiology / Co-Innovation Center for Modern Production Technology of Grain Crops Key Laboratory of Plant Functional Genomics of the Ministry of Education Yangzhou University

Two mutants with rolled leaves, temporally designated as rl3（t）-I and rl3（t）-2, were served for exploring the mechanism underlying the rolled leaf characteristic. Except for having typical rolled leaves, the plant heights and panicle lengths of rl3（t）-1 and rl3（t）-2 significantly decreased, and the seed-setting rate also decreased when compared with wild type 93-11. Cytological analysis suggested that the rolled leaf phenotype might be caused by the changes of number and size of bulliform cells. Genetic analysis indicated rl3（t）-1 is allelic to rl3（t）-2, and controlled by a recessive gene. Gene mapping result indicated that RL3（t） gene resided in a 46-kb long region governed by the sequence tag site markers S3-39 and S3-36 on rice chromosome 3. The result provides an important clue for further cloning the RL3（t） and understanding the mechanism of rice leaf development.

关键词： gene mapping leaf shape formation mutant rice rolled leaf gene