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文学作品欣赏的“显效果”与“隐效果”
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作者 吕留群 《中学语文园地(高中版)》 2000年第9期11-13,共3页
关键词 文学作品欣赏 “显效果” “隐效果” 高中 语文教学 素质教育 艺术情境
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Downscaling and Disaggregating NAO-conflict Nexus in Pre-industrial Europe 被引量:5
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作者 Harry Fung LEE ZHANG David Dian +1 位作者 PEI Qing FEI Jie 《Chinese Geographical Science》 SCIE CSCD 2016年第5期609-622,共14页
Recently, the desiccation effect of the North Atlantic Oscillation(NAO) is found to be positively correlated with violent conflict in pre-industrial Europe, with agricultural shrinkage and its subsequent economic shoc... Recently, the desiccation effect of the North Atlantic Oscillation(NAO) is found to be positively correlated with violent conflict in pre-industrial Europe, with agricultural shrinkage and its subsequent economic shocks to be their causal link. However, it remains unexplored whether the correlation persists if the study period is extended backward in time, a different definition of violent conflict is applied, or the relationship is examined at lower geographic levels. In this study, we based on 835 internal disturbance incidents in Europe during 1049–1800 to conduct long-temporal and multi-scalar examination on the NAO-conflict nexus. ′Time-series′ and ′panel data′ disaggregation approaches, together with Granger Causality, Multiple Regression, and Survival Analyses were applied to verify the nexus quantitatively. Results show that the positive NAO-conflict correlation was significant at the continent and physiographic zone levels. During the positive NAO phases, the annual probability of internal disturbance outbreak increased by 70.0% in the southern Europe and the Mediterranean, a zone most affected by the NAO-induced desiccation effect. Yet, the NAO-conflict correlation was rather inconsistent when it was downscaled to the sub-regional level. Moreover, the NAO-conflict correlation was inflated under the time-series approach, while the panel data approach demonstrated the region-specific nature of the NAO forcing more clearly. The associated implications in examining climate-conflict nexus are discussed. Our findings may be crucial in examining violent conflict in the northwestern Africa, a highly agricultural region affected by the NAO. 展开更多
关键词 climate change North Atlantic Oscillation (NAO) violent conflict internal disturbance EUROPE
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Which Endpoints Can Be Reliably Assessed in Semi-field Pollinator Species Testing without Estimating False Positive or False Negative? MDD’s and Replicates Issue
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作者 Marco Pompeo Candolfi Holger Bargen +4 位作者 Sigrun Bocksch Olaf Klein Marco Kleinhenz Silvio Knaebe Bronislawa Szczesniak 《Journal of Agricultural Science and Technology(A)》 2018年第3期142-161,共20页
Statistical power, number of replicates and experiment complexity of semi-field and field studies on Apis and non-Apis bee species has become a major issue after publication of the draft European Food Safety Authori... Statistical power, number of replicates and experiment complexity of semi-field and field studies on Apis and non-Apis bee species has become a major issue after publication of the draft European Food Safety Authority (EFSA) Guidance on risk assessment of plant protection products (PPP) on bees (Apis mellifera, Bombus spp. and solitary bees). According to this guidance document, field studies have to be designed to be able to detect significance differences as low as 7% for certain endpoints such as reduction in colony size. This will require an immense number of replicates which is obviously not feasible. In the present study, key endpoints such as mortality, termination rate and number of brood cells in honeybee studies, cocoon production and flight activity in solitary bee studies and number of gynes in bumble bee studies (just to mention some of the endpoints considered) in semi-field studies were analyzed, with Apis mellifera, Bombus terrestris and Osmia bicornis during the past five years (2013-2017). The results indicate huge differences in the percentage minimal detectable differences (%MDDs) (MDD expressed as median of control value of the endpoint in percent) depending on endpoint and species tested. For honeybee semi-field studies, the lowest %MDDs recorded were between 10% and 15% for the endpoints foraging, number of brood cells and colony strength. The highest %MDDs were observed for the endpoint termination rate, with a %MDD of almost 50%. For the endpoints in bumble bee semi-field studies the %MDDs varied between 17% for bumble bee colony weight and 53% for average mortality during the exposure period in the tunnel. The %MDD for the number of gynes (young queens) was slightly below 25%. For the semi-field solitary bee test system, the %MDDs for the measured endpoints seem to be lower than those for the other two species tested. The %MDDs for the endpoints hatching of offspring, nest occupation and number of cocoons were 8%, 13% and 14%, respectively. Most of the %MDDs were between 10% and 30% indicating clearly that the currently performed experimental design for the semi-field pollinator studies allowed to determine relatively small effects on key study endpoints. The analysis indicated that for all the three bee species tested, the semi-field test design detected low %MDDs for most of the endpoints. It was also observed that detectable differences between the control and PPP treatments were much lower in semi-field test designs than in field studies with these bee species. The “perfect sample size” really does not exist but test design and statistical analysis can be adapted to lower the %MDDs. Measured and simulated (according to Student’s t-test-distribution) data and results showed that statistical evaluations parameter selection (e.g., alpha value), data transformation (log10) and the number of replicates had a direct effect on the ability of the test design to detect lower or higher %MDD values. It could show that a change of alpha value from 0.05 to 0.1, increases the ability of the studies to detect lower %MDDs. For most of the measured endpoints, increasing the number of replicates e.g., from four to eight, improved the power of the test design by decreasing the %MDD. The reduction magnitude of the %MDD is dependent on the endpoint and selection of statistical parameters such as the alpha value. Parameters that display effects at a biologically relevant scale will be a better indicator for effects than parameters that are able to detect minor differences that are not biologically relevant. 展开更多
关键词 Apis mellifera Bombus terrestris Osmia bicornis OECD75 minimal detectable difference (MDD) statistical power
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Preventive effects of geranylgeranylacetone on rat ethanolinduced gastritis 被引量:12
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作者 Jian-Wen Ning Guan-Bin Lin +2 位作者 Feng Ji Jia Xu Najeeb Sharify 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第18期2262-2269,共8页
AIM:To establish a rat ethanol gastritis model,we evaluated the effects of ethanol on gastric mucosa and studied the preventive effects of geranylgeranylacetone on ethanol-induced chronic gastritis.METHODS:One hundred... AIM:To establish a rat ethanol gastritis model,we evaluated the effects of ethanol on gastric mucosa and studied the preventive effects of geranylgeranylacetone on ethanol-induced chronic gastritis.METHODS:One hundred male Sprague-Dawley rats were randomly divided into 4 equal groups:normal control group,undergoing gastric perfusion of normal saline(NS) by gastrogavage;model control group and 2 model therapy groups that underwent gastric perfusion with ethanol(distillate spirits with 56% ethanol content) by gastrogavage for 4 wk.Low or high doses of geranylgeranylacetone were added 1 h before ethanol perfusion in the 2 model therapy groups,while the same amount of NS,instead of geranylgeranylacetone was used in that model control group.The rats were then sacrificed and stomachs were removed.The injury level of the gastric mucosa was observed by light and electron microscopy,and the levels of prostaglandin 2(PGE 2),endothelin-1(ET-1) and nitric oxide(NO) were measured by radioimmunoassay and the Griess method.RESULTS:The gastric mucosal epidermal damage score(EDS;4.5) and ulcer index(UI;12.0) of the model control group were significantly higher than that of the normal control group(0 and 0 respectively,all P = 0.000).The gastric mucosal EDS and UI of the 2 model therapy groups(EDS:2.5 and 2.0;UI:3.5 and 3.0) were significantly lower than that of the model control group(all P < 0.01).There was no statistically significant difference between the low-dose and high-dose model therapy groups.The expression value of plasma ET-1 of the model control group was higher than that of the normal control group(P < 0.01) and the 2 model therapy groups(all P < 0.01).The expression values of gastric mucosal PGE 2 and serum NO of the model control group were lower than those of the normal control group(all P < 0.05) and the 2 model therapy groups(all P < 0.05).The thickness of the gastric mucous layerand the hexosamine content in the model control group were significantly lower than that in the normal control group(all P < 0.01) and the 2 model therapy groups(all P < 0.05).Scanning and transmission electron microscopy observation showed that in the model control group,the epithelial junctions were vague,the intercellular joints disappeared and damage of the intracellular organelles were significantly worse than those in the normal control group.However,in the 2 model therapy groups,damage to the intercellular joints and organelles was ameliorate relative to the model control group.CONCLUSION:Administration of geranylgeranylacetone was correlated with a more favorable pattern of gastric mucosa damage after ethanol perfusion.The mechanism could be related to regulation of ET-1,NO and PGE 2. 展开更多
关键词 Geranylgeranylacetone Gastritis Ethanol Endothelin-1 Nitric oxide Prostaglandin 2
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Modeling and Rendering in the Three-Dimensional Effect in Rhino for Lady's High Boots
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作者 王立新 李明辉 《Journal of Donghua University(English Edition)》 EI CAS 2011年第2期196-199,共4页
In recent years, the computer drawing technology that deals with three-dimensional (3D) design of footwear has become hot topics. Rhino is a kind of common and practical 3D design software with strong drawing and rend... In recent years, the computer drawing technology that deals with three-dimensional (3D) design of footwear has become hot topics. Rhino is a kind of common and practical 3D design software with strong drawing and rendering graphics function, which is widely used to design industrial products. In this paper, through decomposition and modeling, modeling and drawing methods were analyzed in various parts of footwear by Rhino, as well as the smooth technology and adjustments to its profile curve by an example of lady's high boots. Finally, through a series introductions of rendering effects for footwear in color, light perception, grain characteristic, and 3D graphics, the main technical essential is achieved and difficulties in design of overall footwear styles are solved. 展开更多
关键词 3D effect FOOTWEAR RHINO rendering and modeling
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Effect of chemotherapy on autoimmune hepatitis in thymoma:a case report and literature review
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作者 Nesrine Mejri Imen Chabchoub +4 位作者 Ines Gargouri Imtinen Belaid Faten Ezairi Sihem Hmissa Slim Ben Ahmed 《Cancer Biology & Medicine》 SCIE CAS CSCD 2013年第3期169-173,共5页
Autoimmune hepatitis(AIH) has rarely been described as an autoimmune paraneoplastic syndrome of thymoma.This case is the seventh case of AIH revealed by cholestasis few years after the diagnosis of thymoma and the fir... Autoimmune hepatitis(AIH) has rarely been described as an autoimmune paraneoplastic syndrome of thymoma.This case is the seventh case of AIH revealed by cholestasis few years after the diagnosis of thymoma and the first case treated with chemotherapy alone.We report in this paper a new approach to this rare severe condition.A 29 year-old man presented with chest pain and dyspnea with a history of thymoma surgically removed 4 years ago.CT scan showed the recurrence of an anterior mediastinal mass.Biology showed elevated liver enzymes and profound cholestasis.No sign of viral or toxic hepatitis or bile duct abnormalities were observed.Autoimmune antibodies,except for the anti-nuclear antibody,were negative.Liver biopsy showed active chronic AIH.The patient was diagnosed with recurrent thymoma with AIH and underwent 6 cycles of chemotherapy.A complete response on thymoma and cholestasis was obtained after 10 months of follow-up.Steroids and immunosuppressors are the standard treatment for AIH.The effect of chemotherapy as a specific treatment of this paraneoplastic syndrome needs to be considered. 展开更多
关键词 HEPATITIS AUTOIMMUNE THYMOMA CHEMOTHERAPY
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Influence of Disassociation Probability on External Quantum Efficiency in Organic Electrophosphorescent Devices
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作者 ZHANG Jian-hua OU YANG Jun +1 位作者 LI Xue-yong LI Hong-jian 《Semiconductor Photonics and Technology》 CAS 2007年第3期181-185,共5页
An analytical model is presented to calculate the disassociation probability and the external quantum efficiency at high field in doped organic electrophosphorescence(EPH) devices. The charge recombination process and... An analytical model is presented to calculate the disassociation probability and the external quantum efficiency at high field in doped organic electrophosphorescence(EPH) devices. The charge recombination process and the triplet(T)-triplet(T) annihilation processes are taken into account in this model. The influences of applied voltage and the thickness of the device on the disassociation probability, and of current density and the thickness of the device on the external quantum efficiency are studied thoroughly by including and ignoring the disassociation of excitons. It is found that the dissociation probability of excitons will come close to 1 at high electric field, and the external EPH quantum efficiency is almost the same at low electric field. There is a large discrepancy of the external EPH quantum efficiency at high electric field for including or ignoring the disassociation of excitons. 展开更多
关键词 ELECTROPHOSPHORESCENCE disassociation probability TRIPLET external quantum efficiency
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Effects of coagulation bath temperature on structure and performance of poly(vinyl butyral) hollow fiber membranes via thermally induced phase separation 被引量:2
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作者 张明 邱运仁 《Journal of Central South University》 SCIE EI CAS 2014年第8期3057-3062,共6页
Poly (vinyl butyral) (PVB) hollow fiber membranes were fabricated via thermally induced phase separation (TIPS). The effects of coagulation bath temperature (CBT) on the structure and performance of membranes ... Poly (vinyl butyral) (PVB) hollow fiber membranes were fabricated via thermally induced phase separation (TIPS). The effects of coagulation bath temperature (CBT) on the structure and performance of membranes were investigated in detail. The morphologies of the membranes were studied by scanning electron microscopy (SEM), the performances of water permeability, rejection, breaking strength and elongation were measured, respectively. The results indicate that all the membranes have the asymmetric morphology and the thickness of the skin layer decreases and the pore size of the outer layer increases with the increase of CBT. The permeability of membranes prepared at air gap 1.0 cm and take-up speed 0.253 m/s increases from 1.047×10-7 to 5.909×10-7 m3/(m2·s-kPa) with the CBT increasing from 20 ℃ to 40℃, and sharply increases to 35.226×10 7 m3/(m2.s.kPa)once the CBT arrives at 50 ℃. While the carbonic ink rejections have no significant decrease, totally exceed 98%, but that of acid-maleic acid copolymer greatly decreases with the increase of CBT. Both the breaking strength and elongation decrease with the increase of CBT. 展开更多
关键词 thermally induced phase separation coagulation bath temperature poly (vinyl butyral) hollow fiber membrane
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Direction Dependence of Savings on Cooling and Heating Loads by Energy Efficient Windows
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作者 Kazuki Yoshimura 《Journal of Energy and Power Engineering》 2014年第12期2012-2016,共5页
The energy saving performance of energy efficient windows has strong dependence on window direction. Transmitted insolation level definitely affected the cooling and heating load. Simple simulation on the decrement of... The energy saving performance of energy efficient windows has strong dependence on window direction. Transmitted insolation level definitely affected the cooling and heating load. Simple simulation on the decrement of cooling load and the increment of heating load of a shading window compared with those of a transparent window show the prospect of energy saving effect clearly.From southeastward to southwestward, shading window even enlarges total heating and cooling loads when the thermal transmission is the same. However, if the shading coefficient of window is switched between summer and winter, total cooling and heating load can be reduced. This result clarifies the importance of "smart window". 展开更多
关键词 Cooling load heating load shading coefficient U-vaLue.
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Effect of Microwave Power on the Zn2SnO4 Synthesis and Its Use for Photodegradation of Phenol
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作者 Edson Luiz Foletto Marcio Antonio Mazutti +5 位作者 Adriano Cancelier Erico Marion de Moraes Flores Edson Irineu Muller Leticia Severo Fagundes Pereira Osvaldo Chiavone-Filho Andre Gundel 《Journal of Chemistry and Chemical Engineering》 2014年第8期794-799,共6页
Spinel structure Zn2SnO4 was successfully synthesized by microwave-assisted hydrothermal process. The effects of the microwave power on the formation and physical properties of the Zn2SnO4 particles are discussed. The... Spinel structure Zn2SnO4 was successfully synthesized by microwave-assisted hydrothermal process. The effects of the microwave power on the formation and physical properties of the Zn2SnO4 particles are discussed. The products were characterized by X-ray diffraction, atomic force microscopy, infrared spectroscopy, and N2 adsorption. The results indicated that the microwave power had important influence on the formation of the spinel phase. The results also revealed that the physical properties of Zn2SnO4 particles did not change with the increase of the microwave power above 600 W, with 20 min of reaction time. Furthermore, the photocatalytic activity of the Zn2SnO4 particles for the phenol degradation under sunlight was also investigated. 展开更多
关键词 Zn2SnO4 zinc stannate SYNTHESIS MICROWAVE porous material photocatalysis.
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New Approach to the Strain Analysis of Bragg Grating Sensors 被引量:1
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作者 José R. Alves da CUNHA Petrus Alcantara JR. +2 位作者 Angela Santa BRJGIDA Gilvan BORGES Joāo Weyl COSTA 《Photonic Sensors》 SCIE EI CAS 2013年第1期74-80,共7页
The response of an optical strain sensor based on the fiber Bragg grating is theoretically analyzed with a different approach of that found usually in the literature. In this model, geometrical changes suffered by the... The response of an optical strain sensor based on the fiber Bragg grating is theoretically analyzed with a different approach of that found usually in the literature. In this model, geometrical changes suffered by the grating itself are taken into account. The results are compared with those from experiments, showing very good agreement. 展开更多
关键词 Bragg grating sensor strain sensor Bragg wavelength
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An automatic compensation method on compression effect and surface elasticity measurement based on the deflection signal of AFM 被引量:1
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作者 WEI YangJie WU ChengDong DONG ZaiLi 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第9期2397-2403,共7页
Atomic force microscope (AFM), as an important instrument in micro/nano operation, has been widely used to measure sampie's height information. However, the so called compression effect, due to force aroused from t... Atomic force microscope (AFM), as an important instrument in micro/nano operation, has been widely used to measure sampie's height information. However, the so called compression effect, due to force aroused from the contact of AFM tip with a sample surface, would result in imprecision of the surface's height measurement, i.e., the measured height is lower than expected. Up to now, there is not any effective and rapid method to attenuate this kind of measurement error. Thus, in this paper, an algorithm to obtain high accurate height measurement is proposed. Firstly, the concept of force curve is used to analyze the basic principle of the compression effect. Secondly, an automatic compensation method by fusing the height signal and the deflection signal is proposed. The proposed algorithm can also be used to obtain a surface elasticity image. Finally, in order to validate the proposed method, two experiments are conducted with respect to mufti-wall nano-carbon tubes on a silicon substrate and graphemes on a mica substrate. 展开更多
关键词 atomic force microscope (AFM) compression effect information fusion surface elasticity
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Quasi-Conical Quantum Dot: Electron States and Quantum Transitions
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作者 Eduard M.Kazaryan Lyudvig S.Petrosyan +1 位作者 Vanik A.Shahnazarya Hayk A.Sarkisyan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第2期255-260,共6页
The exactly solvable model of quasi-conical quantum dot, having a form of spherical sector, is proposed. Due to the specific symmetry of the problem the separation of variables in spherical coordinates is possible in ... The exactly solvable model of quasi-conical quantum dot, having a form of spherical sector, is proposed. Due to the specific symmetry of the problem the separation of variables in spherical coordinates is possible in the one- electron Sehrodinger equation. Analytical expressions for wave function and energy spectrum are obtained. It is shown that at small values of the stretch angle of spherical sector the problem is reduced to the conical QD problem. The comparison with previously performed works shows good agreement of results. As an application of the obtained results, the quantum transitions in the system are considered. 展开更多
关键词 conical quantum dot electron states quantum transitions
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Angle-dependent discoloration structures in wing scales of Morpho menelaus butterfly 被引量:4
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作者 NIU ShiChao LI Bo +4 位作者 YE JunFeng MU ZhengZhi ZHANG JunQiu LIU Yan HAN ZhiWu 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第5期749-755,共7页
The Morpho butterfly is famous for its typical structural color and has increasingly attracted the interest of scholars in a wide variety of research fields. Herein, it was found that the color of Morpho menelaus butt... The Morpho butterfly is famous for its typical structural color and has increasingly attracted the interest of scholars in a wide variety of research fields. Herein, it was found that the color of Morpho menelaus butterfly wings is not only structure-based but also viewing-angle-dependent. Firstly, the discoloration effect of this typical butterfly was confirmed by a series of experiments. Then, the general form, arrangements, and geometrical dimensions of the scales were observed using a stereomicroscope. Scanning electron microscopy was also used to examine the two-dimensional morphologies and structures of a single scale. Afterwards, one model with the optimized three-dimensional profile of the structure was described using Pro-engineer software. The associate model was then analyzed to reconstruct the process between the incident light and the model surface. Finally, the mechanism of the angle-dependent discoloration effect was analyzed by theoretical calculation and optical simulation. Different light propagation paths and the length of the incident light at different angles caused destructive or constructive interference between the light reflected from the different layers. The different spectra of the reflected light make the wings appear with different structural colors, thereby endowing the angle-dependent discoloration effect. The consistency of the calculation and simulation results confirms that these structures possess an excellent angle-dependent discoloration effect. This functional "biomimetic structure" would not only be of great scientific interest but could also have a great impact in a wide range of applications such as reflective displays, credit card security, and military stealth technology. 展开更多
关键词 angle-dependent DISCOLORATION structural color BUTTERFLY wing scales BIONICS translight
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Antimicrobial effect of sodium houttuyfonate on Staphylococcus epidermidis and Candida albicans biofilms 被引量:4
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作者 Jing Shao Huijuan Cheng +6 位作者 Daqiang Wu Changzhong Wang Lingling Zhu Zhenxin Sun Qiangjun Duan Weifeng Huang Jinliang Huang 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第6期798-803,共6页
OBJECTIVE: To study antimicrobial effect of Sodi- um houttuyfonate (SH) on Staphylococcus epider- midis (SE) and Candida albicans (CA). METHODS: The prepared strain broths (OD600=0.05) containing SE and CA w... OBJECTIVE: To study antimicrobial effect of Sodi- um houttuyfonate (SH) on Staphylococcus epider- midis (SE) and Candida albicans (CA). METHODS: The prepared strain broths (OD600=0.05) containing SE and CA were firstly used to test the minimal inhibitory concentrations (MICs) of SH, azithromycin (AZM) and fluconazole (FLU) by mi- cro-dilution method. Then the biofilms of SE and CA were matured in 96-well plates, and co-cultured with SH, AZM and FLU for 1, 2 and 3 days to assess the antibiofilm efficacies of the agents with differ- ent concentrations by crystal violet staining meth- od. At last, the treated biofilms of SE and CA by 2× MIC agents were observed by scanning electronic microscope. RESULTS: The MlCs of SE and CA were 256 and 1024 μg/mL, respectively. After the 1st, 2nd and3rd day of medications, the suppressions of biofilm were about 60% (P〈0.01), 76% (P=0.000) and 75% (P=0.000) by 2×MIC SH, the suppressions of biofilm were about 90% (P=0.000), 88% (P=0.000) and 90% (P=0.000) by 2×MIC SH, which could be testified by scanning electron microscope results. However, the inhibitions of biofilm attachment had no significant difference for SE by SH and azithromycin and CA by SH and fluconazole. CONCLUSION: SH had widely anti-pathogenic ef- fect on pathogenic biofilm formation of either bac- teria or fungus, had more influence on enclosed cells of SE and CA than the traditional antibiotics, revealing its target might be the extracellular poly- meric substances, and was more active to inhibit the growth of CA than SE. 展开更多
关键词 Biofilms Candida albicans Drugs Chi-nese herbal Sodium houttuyfonate Staphylococ-cus epidermidis
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