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针刺合谷、三阴交催产机理初探 被引量:32
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作者 林佩冲 刘亚清 +5 位作者 邢福军 罗毓惠 刘青 刘珍 张涛清 金安德 《中国针灸》 CAS CSCD 北大核心 1994年第1期29-31,共3页
本文通过实验研究说明,针刺三阴交、合谷催产是通过降低孕妇血液中孕酮、升高雌二醇含量,以改变孕酮、催产素及孕酮、雌雄激素关系而发挥作用。说明针刺催产是通过调整维持妊娠和分娩发动一些内分泌激素之间的比例关系,而发挥作用的。
关键词 分娩 针灸效应 合谷 三阴交
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A commentary review on the use of normalized diff erence vegetation index(NDVI)in the era of popular remote sensing 被引量:19
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作者 Sha Huang Lina Tang +2 位作者 Joseph P.Hupy Yang Wang Guofan Shao 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第1期1-6,共6页
The Normalized Diff erence Vegetation Index(NDVI),one of the earliest remote sensing analytical products used to simplify the complexities of multi-spectral imagery,is now the most popular index used for vegetation as... The Normalized Diff erence Vegetation Index(NDVI),one of the earliest remote sensing analytical products used to simplify the complexities of multi-spectral imagery,is now the most popular index used for vegetation assessment.This popularity and widespread use relate to how an NDVI can be calculated with any multispectral sensor with a visible and a near-IR band.Increasingly low costs and weights of multispectral sensors mean they can be mounted on satellite,aerial,and increasingly—Unmanned Aerial Systems(UAS).While studies have found that the NDVI is effective for expressing vegetation status andquantified vegetation attributes,its widespread use and popularity,especially in UAS applications,carry inherent risks of misuse with end users who received little to no remote sensing education.This article summarizes the progress of NDVI acquisition,highlights the areas of NDVI application,and addresses the critical problems and considerations in using NDVI.Detailed discussion mainly covers three aspects:atmospheric eff ect,saturation phenomenon,and sensor factors.The use of NDVI can be highly eff ective as long as its limitations and capabilities are understood.This consideration is particularly important to the UAS user community. 展开更多
关键词 NDVI Atmospheric eff ect Saturation phenomenon Calibration MULTISPECTRAL Near infrared UAS Drone remote sensing
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大亚湾核电站低放废水低温废热排放和卷载效应的数值模拟 被引量:8
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作者 张春粦 黄祖湛 +1 位作者 孔令丰 彭建伟 《计算物理》 CSCD 北大核心 1992年第A01期587-592,共6页
用ADI法计算了大亚湾核电站低温废水排放、低温废热排放在周围海域的放射性浓度场,温废场分布和吸水口的卷载效应。
关键词 温度场 数值模拟 放射性 浓度分布
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工艺参数对振动攻丝加工影响的实验研究 被引量:3
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作者 陈学永 何允纪 +2 位作者 蔡兰 何聪惠 王贵成 《江苏理工大学学报(自然科学版)》 2001年第1期4-7,共4页
利用PC机驱动步进电机和钻床改装的攻丝机械构成的步进式振动攻丝系统 ,根据系统情况确定工艺参数的实验范围 利用扭矩传感器测定攻丝扭矩 最后对所采集的扭矩数据进行分析 ,描绘工艺参数与攻丝扭矩关系图形 ,并在现有实验条件下得出... 利用PC机驱动步进电机和钻床改装的攻丝机械构成的步进式振动攻丝系统 ,根据系统情况确定工艺参数的实验范围 利用扭矩传感器测定攻丝扭矩 最后对所采集的扭矩数据进行分析 ,描绘工艺参数与攻丝扭矩关系图形 ,并在现有实验条件下得出工艺参数与振动攻丝扭矩关系的初步结论 展开更多
关键词 钻床 振动攻丝系统 工艺参数 步进式振动 攻丝扭矩
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Therapeutic effect and mechanism of breviscapine on cisplatin-induced nephrotoxicity in mice 被引量:6
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作者 Xiao-Yu Lou Jing-Liang Cheng Bo Zhang 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第10期853-857,共5页
Objective:To observe the protective effect of breviscapineon mice with cisplatin-induced nephrotoxicity.Methods:Mice were given a single injection of cisplalin(8 mg/kg,up.);then,breviscapine was given to mice at 25 mg... Objective:To observe the protective effect of breviscapineon mice with cisplatin-induced nephrotoxicity.Methods:Mice were given a single injection of cisplalin(8 mg/kg,up.);then,breviscapine was given to mice at 25 mg/kg and 50 mg/kg doses,respectively,once a day for seven days.Renal tissue structure was observed after animals were sacrificed.Blood urea nitrogen(BUN),serum creatinine(Scr),lipid peroxide(MDA) and superoxide dismutase(SOD) serum levels were detected;and MDA,glutathione peroxidase,and SOD levels in the renal cortex were detected.Results:Compared with the blank control group(BCG),the kidney pathological damage of mice in the model control group(MCG) was more severe.After applying different doses of breviscapine,different degrees of renal injury improvement appeared.Compared with the BCG,the serum levels of Scr and BUN in the MCG increased to(89.92±6.78) μmoL/L and(15.32±4.53) mmoL/L.The differences were statistical significant(P<0.01).Compared with the MCG,the serum levels of Scr and BUN in the Bre low-dose groups and Bre high-dose groups decreased significantly(P<0.05).Compared with the BCG,the MDA levels in serum and in the renal cortex in the MCG significantly increased,while the SOD levels significantly decreased.Both the differences were statistically significant(P<0.01).In the Bre low-dose groups and Bre high-dose groups,MDA levels in serum and in the renal cortex significantly decreased,while SOD and glutathione peroxidase levels in the renal cortex significantly increased,compared with the MCG;and the differences were statistically significant(P<0.05).Conclusions:Breviscapine can reduce cisplatin induced renal toxicity in mice and it's possible through inhibition of renal tubule cell lipid peroxidation and reduces the nephrotoxicity of cisplatin. 展开更多
关键词 CISPLATIN RENAL INJURY BREVISCAPINE Protective eff
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督脉电针对外伤性截瘫患者尿路功能的改善 被引量:3
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作者 彭享娣 张素洁 +1 位作者 司同 岳秀珍 《中国针灸》 CAS CSCD 北大核心 1994年第S1期84-86,495,共4页
督脉电针疗能有效地对抗输尿管返流,降低膀胱内压,扩大膀胱容量,从而改善膀胱贮尿排尿功能,预防和控制泌尿系感染急性发作。
关键词 穴位 督脉 电针 尿路/针灸效应 尿路感染/预防和控制 膀胱/针灸效应
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The plurality effect of topographical irregularities on site seismic response 被引量:6
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作者 Saeed Ghaffarpour Jahromi Sama Karkhaneh 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第3期521-534,共14页
Topography can have signifi cant eff ects on seismic ground response during an earthquake because topographic irregularities cause considerable diff erences between the seismic waves emitted by the source and the wave... Topography can have signifi cant eff ects on seismic ground response during an earthquake because topographic irregularities cause considerable diff erences between the seismic waves emitted by the source and the waves reaching the ground surface. When a seismic motion happens in a topographically irregular area, seismic waves are trapped and refl ected between the topographic features. Therefore, the interaction between topographies can amplify seismic ground response. In order to reveal how interaction between topographies infl uences seismic response, several numerical fi nite element studies have been performed by using the ABAQUS program. The results show that topographic features a greater distance between the seismic source and the site would cause greater seismic motion amplifi cation and is perceptible for the hills far away from the source and the ridges. Also, site acceleration response is impacted by surrounding topography further than site velocity and displacement response. 展开更多
关键词 TOPOGRAPHY eff ECTS surrounding TOPOGRAPHY site seismic response ABAQUS PROGRAM and PLAXIS PROGRAM
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Protective eff ect of Solanum Nigrum Linn green fruit ethanolic extract on alcoholic liver injury in mice
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作者 Xiaoli Wang Ning Wang +1 位作者 Nan Yang Xiaoshu Zhang 《Journal of Polyphenols》 2024年第3期91-97,共7页
Alcoholic liver injury is a liver disease caused by excessive alcohol consumption,which can lead to chronic liver disease death.Solanum Nigrum Linn taste bitter,cold,has the effect of clearing heat and detoxification,... Alcoholic liver injury is a liver disease caused by excessive alcohol consumption,which can lead to chronic liver disease death.Solanum Nigrum Linn taste bitter,cold,has the effect of clearing heat and detoxification,promoting blood and detumescence.Solanum Nigrum Linn fruit contains a variety of antioxidant enzymes,can remove the body produced by aerobic metabolism harmful substances.In this paper,a model of alcohol-induced liver injury in C57BL/6 mice was established to evaluate the protective eff ect of Solanum Nigrum Linn green fruit(SNGF)ethanolic extract on alcohol-induced liver injury.H&E staining and oil red O(ORO)staining showed that hepatic lobules were clearly demarcated,vacuoles were signifi cantly reduced and lipid droplets were reduced in SNGF ethanolic extract treatment group.Serum levels of TC,TG,LDH,TBA,AKP,ALT and AST were decreased in the SNGF ethanolic extract treatment group,and SNGF ethanolic extract could clear reactive oxygen species(ROS)in time.MDA content was signifi cantly decreased after SNGF ethanolic extract treatment,while superoxide dismutase(SOD)and GSH-Px contents were increased after SNGF ethanolic extract treatment.These results suggest that SNGF ethanolic extract has a protective eff ect on alcohol-induced liver injury. 展开更多
关键词 Solanum Nigrum Linn green fruit ethanolic extract alcoholic liver injury protective eff ect
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Boosted Electrocatalytic Glucose Oxidation Reaction on Noble-Metal-Free MoO_(3)-Decorated Carbon Nanotubes
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作者 Yu-Long Men Ning Dou +3 位作者 Yiyi Zhao Yan Huang Lei Zhang Peng Liu 《Transactions of Tianjin University》 EI CAS 2024年第1期63-73,共11页
Electrocatalytic glucose oxidation reaction(GOR)has attracted much attention owing to its crucial role in biofuel cell fabrication.Herein,we load MoO_(3)nanoparticles on carbon nanotubes(CNTs)and use a discharge proce... Electrocatalytic glucose oxidation reaction(GOR)has attracted much attention owing to its crucial role in biofuel cell fabrication.Herein,we load MoO_(3)nanoparticles on carbon nanotubes(CNTs)and use a discharge process to prepare a noblemetal-free MC-60 catalyst containing MoO_(3),Mo_(2)C,and a Mo_(2)C–MoO_(3)interface.In the GOR,MC-60 shows activity as high as 745μA/(mmol/L cm^(2)),considerably higher than those of the Pt/CNT(270μA/(mmol/L cm^(2)))and Au/CNT catalysts(110μA/(mmol/L cm^(2))).In the GOR,the response minimum on MC-60 is as low as 8μmol/L,with a steady-state response time of only 3 s.Moreover,MC-60 has superior stability and anti-interference ability to impurities in the GOR.The better performance of MC-60 in the GOR is attributed to the abundant Mo sites bonding to C and O atoms at the MoO_(3)–Mo_(2)C interface.These Mo sites create active sites for promoting glucose adsorption and oxidation,enhancing MC-60 performance in the GOR.Thus,these results help to fabricate more effi cient noble-metal-free catalysts for the fabrication of glucose-based biofuel cells. 展开更多
关键词 Interface eff ect ELECTROCATALYSIS Molybdenum oxide GLUCOSE Oxidation reaction
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Metabolomics Combined with Network Pharmacology Uncovers Effective Targets of Tao-Hong-Si-Wu Decoction for Its Protection from Sepsis-Associated Acute Lung Injury 被引量:1
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作者 Jinzhi He Longfei Wang +3 位作者 Yang Wang Zeng Li Feihu Chen Zhicheng Liu 《Journal of Analysis and Testing》 EI CSCD 2023年第2期172-186,共15页
Sepsis-induced acute lung injury(ALI)is a leading cause of death among septic complications.Tao-Hong-Si-Wu decoction(TSD),a classical recipe from traditional Chinese medicine used for treating ischemic stroke,has been... Sepsis-induced acute lung injury(ALI)is a leading cause of death among septic complications.Tao-Hong-Si-Wu decoction(TSD),a classical recipe from traditional Chinese medicine used for treating ischemic stroke,has been recently reported to alleviate inflammation and inflammation-stimulated injuries related to the pathology of ALI.Here,we first observed the therapeutic effect of TSD on sepsis-induced ALI.Based on integrated metabolomics and network pharmacology analysis(NPA)techniques,we aim to understand the mechanism of TSD alleviating ALI.TSD’s effects were observed in rats modeled by cecal ligation and puncture(CLP)and rat macrophages stimulated by lipopolysaccharide(LPS).Metabolomics analyses were applied to determine the ingredients in the medicine and key metabolites correlated to the NPA for the prediction of TSD targets.Gene and protein expressions of the key predicted targets were evaluated in the lung tissue and macrophages of septic model rat by quantitative polymerase chain reaction(PCR)and enzyme-linked immunosorbent assays,respectively.TSD improved survival rate and protected against lung injury in CLP rats.Eleven endogenous metabolites were related to TSD’s actions.TSD significantly suppressed IL-6 and TNF-αsecretions and their gene expressions both in the lung tissue of the model rats and in LPS-stimulated macrophages.TSD also restored decreased lung protein expression of VEGFA in septic model rats.Targeted proteins and their affecting metabolites were finally validated in an external test set of rats.This study shows that metabolomics coupled with NPA is a promising approach to explore potential targets of medicine with complex compositions. 展开更多
关键词 Metabolomics Drug eff ect analysis SEPSIS Traditional Chinese medicine CYTOKINES BIOANALYSIS
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人工模拟飞播牧草对治理“黑土滩”型退化草地的效果调查 被引量:5
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作者 拉元林 梁珠英 《青海草业》 2000年第4期32-34,共3页
采用路线定点抽样方法 ,对人工模拟飞播治理“黑土滩”进行了调查 ,结果表明 ,飞播后平均每公顷鲜草产量 991 2 .6kg,比播前提高了 1 1 .5 5倍 ;植被盖度达 70 %~ 80 % ;草群结构改变 ,一些已消失了的优良牧草相继出现 ,不食毒杂草大... 采用路线定点抽样方法 ,对人工模拟飞播治理“黑土滩”进行了调查 ,结果表明 ,飞播后平均每公顷鲜草产量 991 2 .6kg,比播前提高了 1 1 .5 5倍 ;植被盖度达 70 %~ 80 % ;草群结构改变 ,一些已消失了的优良牧草相继出现 ,不食毒杂草大幅度下降 ,治理效果良好。 展开更多
关键词 飞播牧草 治理“黑土滩” 效果
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NIR Light-Promoted Whole-Cell Catalysis Based on a Light-Harvesting Blackbody Bioreactor
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作者 Jinhui Gu Qisi Li +5 位作者 Mengting Cao Xiaojia Zhang Xinpei Ding Haiyan Chen Nan Wang Zhijun Zhang 《Journal of Analysis and Testing》 EI CSCD 2023年第3期237-244,共8页
Whole-cell catalysis,which utilizes enzymes expressed in whole organism(e.g.bacteria and fungi)as the catalyst,is a specific mode of biocatalysis.Compared with pure enzyme catalysis,the catalysis with whole-cell catal... Whole-cell catalysis,which utilizes enzymes expressed in whole organism(e.g.bacteria and fungi)as the catalyst,is a specific mode of biocatalysis.Compared with pure enzyme catalysis,the catalysis with whole-cell catalysts is more cost-effective.However,in the process of whole-cell catalysis,heat treatment is often necessary due to the high optimum temperature of the enzyme.To enable efficient industrial application of whole-cell catalysis,an environmental friendly heating approach is highly desired.Inspired by the light harvest by blackbody materials,in this paper,we introduced a photothermal approach for harnessing the photon energy for enhanced whole-cell catalysis.A blackbody porous sponge(BPS)with excellent photothermal conversion efficiency was prepared as a bioreactor.Escherichia coli expressed with a thermophilic enzyme(β-glucosidase)was utilized as a model whole-cell catalyst.Moreover,the photothermal properties of the BPS and lightassisted whole-cell catalysis were systematically investigated,demonstrating promising application prospects. 展开更多
关键词 Whole-cell catalysis BIOCATALYSIS Photothermal eff ect Near-infrared light response Blackbody materials Porous sponge
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Testing phaeophytinization as an index of ozone stress in trees
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作者 Evgenios Agathokleous Mitsutoshi Kitao Takayoshi Koike 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第4期1167-1174,共8页
Ground-level ozone pollution is a menace for vegetation in the northern hemisphere,limiting photosynthetic pigments and suppressing photosynthesis in trees and other types of plants.Phaeophytinization is the process o... Ground-level ozone pollution is a menace for vegetation in the northern hemisphere,limiting photosynthetic pigments and suppressing photosynthesis in trees and other types of plants.Phaeophytinization is the process of converting chlorophylls into phaeophytins,for example by acidifi cation.Ozone is a highly oxidizing molecule and well known to degrade chlorophylls;however,the eff ect of ozone on phaeophytinization in leaves of higher plants is largely unknown.To reveal ozone eff ect on phaeophytinization and evaluate the potential of phaeophytinization as an index of ozone stress in trees,the absorbance at the optical density of 665 nm was measured before(OD_(665))and after(OD_(665a))acidifi cation in three independent experiments with nearly 30 conditions of ozone exposure.Both current ambient and elevated ozone widely aff ected phaeophytinization,as indicated by decreases or increases in the phaeophytinization quotient OD_(665)/OD_(665a).These eff ects were commonly moderate to large in magnitude and practically signifi cant,and occurred even in ozone-asymptomatic leaves.It emerges that the ozone eff ect on phaeophytinization is bimodal,likely depending on the intensity of ozone stress.These results indicate a promising feature of OD_(665)/OD_(665a)as a thorough index of ozone stress in the future,but further studies are needed to reveal the underlying biochemical mechanisms of the bimodal eff ect on phaeophytinization. 展开更多
关键词 Biological stress Chemical eff ect Chlorophyll oxidation Environmental stimuli Phaeophytin
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Effect size in papers published by the Journal of Forestry Research:A missing treasure?
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作者 Evgenios Agathokleous Lei Yu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第2期297-299,共3页
P values based on standard hypothesis testing are commonly reported in articles published by the Journal of Forestry Research(JFR).However,effect sizes are barely used and reported,even if they are of direct relevance... P values based on standard hypothesis testing are commonly reported in articles published by the Journal of Forestry Research(JFR).However,effect sizes are barely used and reported,even if they are of direct relevance to the primary questions of many of the published studies.The incorporation of effect sizes in studies published by JFR should be encouraged and promoted.Inclusion of effect sizes as a requirement in the journal guidelines will facilitate a major change in the way data are tested and interpreted,with the ultimate goal to exempt researchers from the custom of drawing conclusions merely based upon a dichotomous statistical result(P value).Such a policy can also lead to more informed decisions of whether identified effects are of practical relevance to the forestry. 展开更多
关键词 eff ect magnitude Null hypothesis signifi cance testing P value Science communication Scientifi c writing
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Single and combined eff ects of fertilization,ectomycorrhizal inoculation,and drought on container-grown Japanese larch seedlings
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作者 Evgenios Agathokleous Mitsutoshi Kitao +3 位作者 Masabumi Komatsu Yutaka Tamai Hisanori Harayama Takayoshi Koike 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第4期1077-1094,共18页
Climate change can intensify drought in many regions of the world and lead to more frequent drought events or altered cycles of soil water status.Therefore,it is important to enhance the tolerance to drought and thus ... Climate change can intensify drought in many regions of the world and lead to more frequent drought events or altered cycles of soil water status.Therefore,it is important to enhance the tolerance to drought and thus health,vigor,and success of transplantation seedlings used in the forestry by modifying fertilization and promoting mycorrhization.Here,we sowed seeds of Japanese larch(Larix kaempferi)in 0.2-L containers with 0.5 g(low fertilization;LF)or 2 g(high fertilization;HF)of slow-release fertilizer early in the growing season.One month later,we irrigated seedlings with non-sterilized ectomycorrhizal inoculum(ECM)or sterilized solution(non-ECM),and after about 2 months,plants were either kept well watered(WW;500 mL water/plant/week)or subjected to drought(DR;50 mL water per plant/week)until the end of the growing season.HF largely stimulated plant growth and above-and belowground biomass production,eff ects that are of practical signifi cance,but caused a small decrease in stomatal conductance(Gs 390)and transpiration rate(E 390),which in practice is insignifi cant.ECM treatment resulted in moderate inhibition of seedling growth and biomass and largely canceled out the enhancement of biomass and foliar K content by HF.DR caused a large decrease in CO 2 assimilation,and enhanced stomatal closure and induced senescence.DR also largely depleted foliar Mg and enriched foliar K.Although DR caused a large decrease in foliar P content in LF,it moderately increased P in HF.Likewise,DR increased foliar K in HF but not in LF,and decreased foliar P in ECM plants but not in non-ECM plants.Conversely,ECM plants exhibited a large enrichment in foliar P under WW and had a lower water potential under DR when grown in LF.These results indicate that the drought tolerance and health and vigor of Japanese larch seedlings can be modifi ed by soil fertility and soil microorganisms.This study provides a basis for new multifactorial research programs aimed at producing seedlings of superior quality for forestation under climate cha 展开更多
关键词 DROUGHT ECTOMYCORRHIZAE Fertilizer eff ect Oxidative stress Stressor interactions
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Near-Infrared Light-Activatable Melanized Paclitaxel Nano-Self-Assemblies for Synergistic Anti-tumor Therapy
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作者 Qiming Zhu Peizhe Li +5 位作者 Qiwen Huang Xinpei Ding Nan Wang Weijun Yao Maozhong Miao Zhijun Zhang 《Journal of Analysis and Testing》 EI CSCD 2023年第3期204-214,共11页
Building self-assembly nanostructures is an important way to overcome the limitations of paclitaxel in tumor therapy.However,this strategy is also faced with challenges,such as difficulties in efficient release and th... Building self-assembly nanostructures is an important way to overcome the limitations of paclitaxel in tumor therapy.However,this strategy is also faced with challenges,such as difficulties in efficient release and the potential for drug resistance.Herein,we developed a near-infrared light-activatable melanized paclitaxel self-assembly nanoparticles for synergistic anti-tumor therapy.In this strategy,paclitaxel dimer prodrugs were synthesized and paclitaxel nanoparticles were obtained through self-assembly.Finally,the paclitaxel dimer nanoparticles were capped with polydopamine(PDA,melanoidin)and human serum albumin(HSA).The disulfide bonds in paclitaxel dimeric prodrug specifically respond to high concentrations of glutathione(GSH)and reactive oxygen species(ROS)in tumor cells.PDA enhances the biocompatibility of the drug molecules and imparts near-infrared photothermal conversion capability to the nano-self-assemblies.Both the in vitro and in vivo experiments demonstrated that this paclitaxel nanoprodrug exhibited enhanced tumor therapeutic efficacy under near-infrared light irradiation. 展开更多
关键词 Paclitaxel nano-self-assemblies Synergistic anti-tumor therapy Photothermal eff ect MELANOIDINS Nearinfrared light-activatable
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Effect of site amplification on inelastic seismic response 被引量:4
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作者 Adhikary S Singh Y 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第3期535-554,共20页
The available models for eff ective periods of site and structure are reviewed in context of frequency tuning in the inelastic seismic response of soil-structure system. The eff ect of seismic intensity and ductility ... The available models for eff ective periods of site and structure are reviewed in context of frequency tuning in the inelastic seismic response of soil-structure system. The eff ect of seismic intensity and ductility demand, on the eff ective periods, is investigated, and inelastic site amplifi cation is shown to be strongly correlated to the normalized eff ective period. Two non-dimensional parameters, analogous to the conventional site amplifi cation factors in codes, are defi ned to quantify the inelastic site amplifi cation. It is shown that the inelastic site amplifi cation factor (i.e. ratio of constant ductility spectral ordinates at soil site to those at rock outcrop) is able to represent the site eff ects more clearly, as compared to the inelastic site amplifi cation ratio (i.e. ratio of inelastic spectral ordinates at soil site to the corresponding elastic spectral ordinates at rock outcrop). Further, the peak in the amplifi cation factor corresponding to the eff ective site period diminishes rapidly with increasing ductility demand. 展开更多
关键词 SITE amplifi CATION normalized RESPONSE SPECTRA eff ective period INELASTIC SEISMIC RESPONSE INELASTIC SITE amplifi CATION factor
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Effects of site productivity on individual tree maximum basal area growth rates of Eucalyptus pilularis in subtropical Australia
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作者 P.W.West 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1659-1668,共10页
Inventory data were available from 96 plots of even-aged,monoculture,tall-open forests of Eucalyptus pilularis Smith,aged 2-63 years,growing in sub-tropical regions along the east coast of Australia.A model was develo... Inventory data were available from 96 plots of even-aged,monoculture,tall-open forests of Eucalyptus pilularis Smith,aged 2-63 years,growing in sub-tropical regions along the east coast of Australia.A model was developed relating the maximum possible stem basal area growth rate of individual trees to their stem basal area.For any tree size,this maximum increased as site productivity increased.However,the size at which this maximum occurred decreased as productivity increased.Much research has shown that,at any stand age,trees of a particular stem basal area are taller on more productive sites than on less productive ones.Taller trees incur greater respiratory costs to ensure maintenance of the photo synthetic capacity of their canopies;this reduces their growth rates.It was concluded that trees with larger basal areas will have the maximum possible growth rate on a less productive site,whilst trees with smaller basal areas will have the maximum possible on a more productive site.The model developed may constitute the first stage of a complete individual tree growth model system to predict wood yields from these forests. 展开更多
关键词 Growth model Individual tree Maximum growth rate Eucalyptus pilularis Physiological eff ects
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以PET/CT图像为基准的能谱CT平扫成像在宫颈癌中诊断价值的初步探索 被引量:3
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作者 沈高耀 辛军 +2 位作者 孙洪赞 李文华 邱健 《现代肿瘤医学》 CAS 2020年第14期2482-2486,共5页
目的:初步探索以PET/CT图像为基准的能谱CT平扫成像在宫颈癌诊断中的应用价值。方法:回顾性收集我院21例病理证实为宫颈鳞状细胞癌的患者,所有患者术前均行PET/CT扫描及能谱CT扫描,以PET/CT融合图像为参照,在能谱CT图像上勾画感兴趣区,... 目的:初步探索以PET/CT图像为基准的能谱CT平扫成像在宫颈癌诊断中的应用价值。方法:回顾性收集我院21例病理证实为宫颈鳞状细胞癌的患者,所有患者术前均行PET/CT扫描及能谱CT扫描,以PET/CT融合图像为参照,在能谱CT图像上勾画感兴趣区,记录宫颈癌病灶及周围正常组织有效原子序数(effective atomic number,Eff-Z)值、单能量70 keV下的CT值和能谱曲线,绘制ROC曲线,得出最佳诊断阈值。结果:宫颈癌病灶及周围正常组织的Eff-Z值及70 keV下的CT值差异具有统计学意义(P<0.05)。宫颈癌病灶Eff-Z值为7.33±0.09(7.1~7.5);病灶周围正常组织Eff-Z值为7.01±0.10(6.8~7.2);Eff-Z为7.25时,敏感度为90.5%,特异度为100%。70 keV单能量重建成像宫颈癌病灶CT值为(38.27±5.04)HU(29.2~50.9 HU),病灶周围正常组织CT值为(29.79±7.14)HU(19.9~43.1 HU);CT值为34.2 HU时,敏感度为85.7%,特异度为76.2%。宫颈癌病灶能谱曲线平直,病灶周围正常组织曲线在40~70 keV呈上升趋势,之后趋于平缓。结论:能谱CT在宫颈癌诊断中有一定的作用。 展开更多
关键词 宫颈癌 能谱CT 有效原子序数 PET/CT
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Mesoscale SST perturbation-induced impacts on climatological precipitation in the Kuroshio-Oyashio extension region,as revealed by the WRF simulations 被引量:3
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作者 GAO Jiaxiang ZHANG Rong-Hua WANG Hongna 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第2期385-397,共13页
Mesoscale coupling between perturbations of mesoscale sea surface temperature (SST) and lowlevel winds has been extensively studied using available high-resolution satellite observations. However, the climatological i... Mesoscale coupling between perturbations of mesoscale sea surface temperature (SST) and lowlevel winds has been extensively studied using available high-resolution satellite observations. However, the climatological impacts of mesoscale SST perturbations (SST meso ) on the free atmosphere have not been fully understood. In this study, the rectified eff ect of SSTmeso on local climatological precipitation in the Kuroshio- Oyashio Extension (KOE) region is investigated using the Weather Research and Forecasting (WRF) Model;two runs are performed, one forced by low-resolution SST fields (almost no mesoscale signals) and another by additional high-resolution SSTmeso fields extracted from satellite observations. Climatological precipitation response to SST meso is characterized mainly by enhanced precipitation on the warmer flank of three oceanic SST fronts in this region. The results show that the positive correlation between the 10-m wind speed perturbations and SSTmeso is well captured by the WRF model with a reasonable spatial pattern but relatively weak strength. The addition of SSTmeso improves the climatological precipitation simulated by WRF with a better representation of fine-scale structures compared with satellite observations. A closer examination on the underlying mechanism suggests that while the pressure adjustment mechanism can explain the climatological precipitation enhancement along the fronts and the relatively high contribution of the convective precipitation, other factors such as synoptic events should also be taken into consideration to account for the seasonality of the precipitation response. 展开更多
关键词 MESOSCALE SST perturbations and eff ects WRF model Kuroshio-Oyashio EXTENSION climatological PRECIPITATION
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