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Pun's Effectiveness and Selectivity in English Advertisements 被引量:1
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作者 王爽 《英语广场(学术研究)》 2011年第Z4期73-76,共4页
This paper lays particular emphasis on pun's effectiveness and selectivity in English advertisements.The illustration and examples can help us understand the English advertisements well and foster our ability to a... This paper lays particular emphasis on pun's effectiveness and selectivity in English advertisements.The illustration and examples can help us understand the English advertisements well and foster our ability to appreciate the charm of English. 展开更多
关键词 ENGLISH ADVERTISEMENTS PUN effectIVENESS selectIVITY
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Selectivity and sublethal effects of some frequently-used biopesticides on the predator Cyrtorhinus lividipennis Reuter(Hemiptera: Miridae) 被引量:2
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作者 DAI Wei LI Yao +3 位作者 ZHU Jun GE Lin-quan YANG Guo-qing LIU Fang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第1期124-133,共10页
The green miridbug,Cyrtorhinus lividipennis,is an important predator of the rice brown planthopper,Nilaparvata lugens.In this study,the selective toxicity of seven commercial biopesticides for C.lividipennis was exami... The green miridbug,Cyrtorhinus lividipennis,is an important predator of the rice brown planthopper,Nilaparvata lugens.In this study,the selective toxicity of seven commercial biopesticides for C.lividipennis was examined under laboratory conditions; abamectin was the most selective to C.lividipennis,followed by matrine and azadirachtin.Veratridine,rotenone,Bacillus thuringiensis and Beauveria bassiana showed less selectivity for C.lividipennis.Subsequently,matrine,abamectin and azadirachtin were selected for sublethal assessments with respect to C.lividipennis due to their high toxicities to N.lugens.C.lividipennis treated with sublethal concentrations(LC10 and LC20) of the three biopesticides could distinguish volatiles released from healthy and N.lugens-infested plants indicating that the biopesticides tested did not affect the foraging ability of surviving miridbugs.Azadirachtin decreased the consumption capability of C.lividipennis when the densities of N.lugens were 20,30,40 and 50 insects per vial.Sublethal concentration treatment did not impact the pre-oviposition period or egg hatchability of C.lividipennis.However,the fecundity of C.lividipennis exposed to azadirachtin and abamectin increased by 27–41% compared to the untreated individuals.In summary,abamectin or matrine together with C.lividipennis could be considered an effective,sustainable pest management strategy for rice. 展开更多
关键词 BIOPESTICIDES Cyrtorhinus lividipennis selective toxicity SUBLETHAL effects
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Effect of Two Phase Mixtures on the Selection of the Discharge Path 被引量:1
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作者 DENG He-ming HE Zheng-hao WANG Lei LI Jin 《高电压技术》 EI CAS CSCD 北大核心 2008年第12期2681-2686,共6页
This paper investigates the development,the breakdown process,and the discharge path selection of the lightning discharges in two-phase mixtures(TPMs).13 kinds of solid-gas mixtures and 3 kinds of liquid-gas mixtures ... This paper investigates the development,the breakdown process,and the discharge path selection of the lightning discharges in two-phase mixtures(TPMs).13 kinds of solid-gas mixtures and 3 kinds of liquid-gas mixtures are employed to study effect of two phase mixtures on the selection of the discharge path under lightning impulses.Grain size effects are shown upon these experimental results.When the diameter of solid or liquid grains is less than about 10 μm,the discharge path does not select TPM but air.And the discharge path selects TPM when the diameter is greater than about 100 μm.And when the diameter is between about 10 μm and 100 μm,the discharge path selects TPM under negative lightning impulses,but it has a greater selection of air than TPMs under positive lightning impulses.Volume fraction and permittivity of solid/liquid can also influence the selection of the discharge path. 展开更多
关键词 混合两相体 放电路径 选择 粒度效应 容积率 介电常数
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Neighbour Peer Selection Scheme Based on Effective Capacity for Mobile Peer-to-Peer Streaming
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作者 夏海轮 王宁 曾志民 《China Communications》 SCIE CSCD 2013年第5期89-98,共10页
For Peer-to-Peer (P2P) streaming services in mobile networks, the selection of appropriate neighbour peers from candidate peers with demanding data is an important approach to improve Quality-of-Service (QoS). This pa... For Peer-to-Peer (P2P) streaming services in mobile networks, the selection of appropriate neighbour peers from candidate peers with demanding data is an important approach to improve Quality-of-Service (QoS). This paper proposes a novel Effective Capacity Peer Selection (ECPS) scheme based on effective capacity. In the ECPS scheme, the neighbour peer selection problem was modeled using the Multiple Attribute Decision Making (MADM) theory, which considered multiple factors of candidate peers, including Signal to Interference and Noise Ratio (SINR), residency time, power level, security, moving speed, and effective capacity. This model could increase the suitability of ECPS for wireless mobile environments. Then, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) was used to solve the MADM problem and identify the preferred neighbour peers. Simulation results show that the ECPS scheme can improve the network throughput, reduce packet delay by about 82%, and almost double the packet delivery ratio of the mobile P2P streaming service. 展开更多
关键词 P2P mobile P2P streaming peer selection effective capacity MADM QoS
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China's Low Export Markups Puzzle: Competition Effect and Selection Effect
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作者 Xu Ming 《China Economist》 2019年第3期98-113,共16页
Based on China's industrial enterprises-customs matched data, this paper utilizes two-tier stochastic frontier analysis method to estimate and verify the extent to which selection effect and competition effect inf... Based on China's industrial enterprises-customs matched data, this paper utilizes two-tier stochastic frontier analysis method to estimate and verify the extent to which selection effect and competition effect influence exporting firms' markup. Our findings suggest that the interaction between selection effect and competition effect ultimately causes actual firm markup to be higher than the baseline markup by 7.11%. Exporting firms' actual markup is higher than the baseline markup by different degrees. In terms of the decomposition of selection effect, TFP explains for 28.05% of selection effect, and nonproductivity factors explain for the rest 71.95%. By controlling for the type of firms' export,the export-productivity paradox only exists for processing trade firms, which shows that with increasing trade facilitation, the policy incentives to encourage firms to export are major contributors to the low export markups. 展开更多
关键词 LOW EXPORT MARKUPS PUZZLE COMPETITION effect selection effect two-tier stochastic frontier analysis
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Submicro-battery effect and selective bio-oxidation model of gold-bearing arsenopyrite by Thiobacillus ferrooxidans 被引量:4
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作者 杨洪英 杨立 +3 位作者 赵玉山 陈刚 吕久吉 范有静 《中国有色金属学会会刊:英文版》 CSCD 2002年第6期1199-1202,共4页
Through the study by electronic probe it was found that many new cracks and holes appear on the surface of gold bearing arsenopyrite crystal oxidized by Thiobacillus ferrooxidans, which are along with some directions.... Through the study by electronic probe it was found that many new cracks and holes appear on the surface of gold bearing arsenopyrite crystal oxidized by Thiobacillus ferrooxidans, which are along with some directions. Then the selective bio oxidation model of gold bearing arsenopyrite was set up. The selective bio oxidation resulting from the submicro battery effect of gold/ arsenopyrite mineral pairs naturally forms in the gold bearing arsenopyrite crystal. Thiobacillus ferrooxidans has priority to oxidize the place of gold rich and oxidizes selectedly along with the crystal border, crystal face and crack. The bacteria oxidation process of gold bearing arsenopyrite is divided into three stages: the first stage is the surface oxidation, the second stage is restraining oxidation and the third stage is the filament oxidation, bacteria oxidize along with cracks of arsenopyrite. 展开更多
关键词 选择性生物氧化模型 亚微米电池效应 砷黄铁矿 铁氧化剂
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基于JABBA-Select模型对不同时间序列渔获量和渔船效应的印度洋长鳍金枪鱼资源评估
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作者 杨诗玉 冯佶 朱江峰 《大连海洋大学学报》 CAS CSCD 北大核心 2023年第5期828-838,共11页
为了解印度洋长鳍金枪鱼(Thunnus alalunga)种群动态及资源开发利用状况,采用结合了种群生物学参数和渔业选择性的JABBA-Select模型,分别从渔获量的不同时间序列、单位捕捞努力量渔获量(CPUE)标准化过程是否考虑渔船效应两个方面,考察... 为了解印度洋长鳍金枪鱼(Thunnus alalunga)种群动态及资源开发利用状况,采用结合了种群生物学参数和渔业选择性的JABBA-Select模型,分别从渔获量的不同时间序列、单位捕捞努力量渔获量(CPUE)标准化过程是否考虑渔船效应两个方面,考察对印度洋长鳍金枪鱼资源量评估结果的影响。结果表明:当模型选取1979-2020年短时间序列渔获量数据时,CPUE的拟合效果更好;而当模型选取长时间序列渔获量数据时,CPUE对数残差较大,拟合效果较差;同时考虑渔船效应的CPUE数据对模型拟合效果表现更佳;2020年印度洋长鳍金枪鱼未发生资源型过度捕捞(B_(SB)/B_(SB),MSY>1),也未发生捕捞型过度捕捞(F/F_(MSY)<1);模型重要参数的敏感性分析显示,种群评估结果对陡度(steepness,h)较稳健,但对自然死亡率(natural mortality,M)较敏感。研究表明,不同时间序列的渔获量对资源评估结果存在较大差异,考虑渔船效应的标准化CPUE可以更好地反映种群资源变动趋势,减少种群评估结果的不确定性。 展开更多
关键词 长鳍金枪鱼 JABBA-select模型 渔船效应 资源评估 印度洋
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EFFECT OF ELECTRON DONORS ON THE SELECTIVE HYDROGENATION OF DIENE TO MONOENE OVER HETEROGENIZED Pd CATALYST
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《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第4期263-264,共2页
In the selective hydrogenation of diene (or alkyne) using heterogenized homogeneous catalyst, the high selectivity of monoene formation only appears in a very short time interval. The addition of suitable electron don... In the selective hydrogenation of diene (or alkyne) using heterogenized homogeneous catalyst, the high selectivity of monoene formation only appears in a very short time interval. The addition of suitable electron donors can decrease or even cease the monoene hydrogenation and thereby keep the high monoene selectivity after reaching its maximum. 展开更多
关键词 PD effect OF ELECTRON DONORS ON THE selectIVE HYDROGENATION OF DIENE TO MONOENE OVER HETEROGENIZED Pd CATALYST HIGH
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Automatic Variable Selection for Single-Index Random Effects Models with Longitudinal Data
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作者 Suigen Yang Liugen Xue 《Open Journal of Statistics》 2014年第3期230-237,共8页
We consider the problem of variable selection for the single-index random effects models with longitudinal data. An automatic variable selection procedure is developed using smooth-threshold. The proposed method share... We consider the problem of variable selection for the single-index random effects models with longitudinal data. An automatic variable selection procedure is developed using smooth-threshold. The proposed method shares some of the desired features of existing variable selection methods: the resulting estimator enjoys the oracle property;the proposed procedure avoids the convex optimization problem and is flexible and easy to implement. Moreover, we use the penalized weighted deviance criterion for a data-driven choice of the tuning parameters. Simulation studies are carried out to assess the performance of our method, and a real dataset is analyzed for further illustration. 展开更多
关键词 VARIABLE selectION Single-Index MODEL RANDOM effects Longitudinal DATA
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Selection Effects of Soil Fertility on the Progenies of Soybean Crosses
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作者 Zou Jijun, Yang Qingkai, Wang Jiming(Northeast Agricultural University, Harbin 150030, PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1996年第2期88-93,共6页
The F2, F3, families and F4 lines of six soybean crosses, were selected successively under high-and low - fertility sites with the relection objective of high yield and the method of pedigree was used. Two best F4 - d... The F2, F3, families and F4 lines of six soybean crosses, were selected successively under high-and low - fertility sites with the relection objective of high yield and the method of pedigree was used. Two best F4 - derived lines were chosen from each of the six crosses under both high-and low-fertility for use in this study. In 1995, the total 24 lines were tested in high, medium and low fertility sites with the same experimental design (CRB) to study the selcctoin effects of high and low - fertility. The results suggested that high- and low-fertility had different selection effects. High fertility was more effective for selecting lines, which had higher yield under high-fertility and lower yield under low-fertility; low-fertility was better for selecting lines, which had higher yield under low-fertility and lower yield under low-fertility, and high fertility was somewhat better than low fertility for selecting lines, which had higher yield under both high and low-fertility. It revealed that the lines selected from high-fertility had superior yield potential. The lines selected from high-fertility had shorter plant height, more nodes on main stem, fewer branches, higher seed-stem ratio. The reverse was true for the lines selected from low-fertility . The lodging-resistance of the lines selected from highfertility was greater than that of the lines from low-fertility. The soil fertility level of breeding nursery should be chosen according to the breeding objective. 展开更多
关键词 progenics or soybean crosses soil fertility selection effects
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Immunomodulatory effects of selected Malaysian plants on the CD18/11a expression and phagocytosis activities of leukocytes
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作者 Nurul Hikmah Harun Abdi Wira Septama Ibrahim Jantan 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第1期48-53,共6页
Objective:To investigate the effects of 20 methanolic extracts from Malaysian selected plants on CD18/11 a expression and phagocytosis activity of leukocytes using flow cytometry analysis.Methods:The effects of methan... Objective:To investigate the effects of 20 methanolic extracts from Malaysian selected plants on CD18/11 a expression and phagocytosis activity of leukocytes using flow cytometry analysis.Methods:The effects of methanolic extracts on CD18/11 a expression and phagocytosis of leukocytes were measured by labelling the cells with CD18-fluorescein isolhiocyanaie and ingestion labelled with Escherichia coli-fluorescein isothiocyanate and then analyzed using flow cytometer.Results:About 12 out of 20 methanolic extracts of selected Malaysian medicinal plants significantly(P≤0.05) inhibited the CD18/1 la expression of leukocytes at both concentrations of 6.25 μg/mL and 100 μg/mL in dose dependent manner.The most active inhibitory was shown in Citrus aurantifolia(Christm.) Swingle and Alpinia galangal(L.) Willd.at dosage 100ug/mL.Moreover,the Orthosiphon aristatus(Blume) Miq(O.aristatus).showed the highest stimulatory activity at the concentration of 100 μg/mL.Other than that,four plant extracts significantly(P<0.05) rose the phagocytosis activities of leukocytes in dose dependent manner.However,Annona muricata L.and O.aristatus showed the highest stimulated activities at the 100 pg/mL concentration.Conclusions:The results suggest that methanolic extracts of Cirrus aurantifolia.Alpinia gaiangal,O.aristatus and Annona muricata are able to modulate innate immune system and can potentially be recognized as therapeutic agents for modulating immune system. 展开更多
关键词 selectED MALAYSIAN medicinal PLANTS Immunomodulatory effects CD18/11a EXPRESSION PHAGOCYTOSIS activity Flow cytometry analysis
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融合动态特征与注意力的敦煌壁画修复模型
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作者 刘仲民 严梁 《计算机工程》 CAS CSCD 北大核心 2024年第5期342-353,共12页
敦煌壁画图像含有丰富的纹理和结构信息,在破损壁画修复过程中,容易忽略受损特征信息与完整特征信息之间的区别,从而误导修复过程生成不合理的壁画内容。针对该问题,提出一种融合动态特征选择和像素级通道注意力的壁画修复模型。设计基... 敦煌壁画图像含有丰富的纹理和结构信息,在破损壁画修复过程中,容易忽略受损特征信息与完整特征信息之间的区别,从而误导修复过程生成不合理的壁画内容。针对该问题,提出一种融合动态特征选择和像素级通道注意力的壁画修复模型。设计基于U-Net的网络生成器,实现对破损图像的编码与解码操作;采用有效可迁移卷积模块,通过动态选择采样空间位置,实现对有效特征信息的灵活提取,采用区域综合归一化模块减少修复区域与完整区域的期望和方差的偏移,从而加强对有效特征信息的选择和利用;在解码层设计像素级通道注意力模块,在增强有效特征权重的同时使模型可从相隔较远的空间位置学习有效特征。在敦煌壁画数据集上的实验结果表明,该算法能够利用有效信息修复掩膜区域比例不一的不规则破损壁画图像,相比PConv、PRVS、DSNet算法,在峰值信噪比(PSNR)指标上平均提升0.502 d B,在结构相似性(SSIM)指标上平均提升1.384%。 展开更多
关键词 信息处理技术 壁画修复 深度学习 有效特征选择 注意力机制
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《毛泽东选集》中的反讽修辞及其韩译研究
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作者 姜龙范 刘天骄 《天津外国语大学学报》 2024年第3期56-65,111,共11页
《毛泽东选集》中运用了大量的反讽修辞,具体表现为反语、夸张、对比、反问等修辞技巧,在诗学层面形成了独特的文体风格,在哲学层面表现了大无畏的精神世界与乐观积极的革命热情。对反讽修辞的翻译需要译者在准确传达表层含义的同时再... 《毛泽东选集》中运用了大量的反讽修辞,具体表现为反语、夸张、对比、反问等修辞技巧,在诗学层面形成了独特的文体风格,在哲学层面表现了大无畏的精神世界与乐观积极的革命热情。对反讽修辞的翻译需要译者在准确传达表层含义的同时再现原文的反讽情境,实现修辞表达者的交际目的。译者如何接受原文修辞并在译文中重建修辞世界,取决于两种语言的语境差异,以及译者个人的修辞意识、修辞能力及认知体系。而具体翻译策略与技巧的选择决定着译文的修辞效果。 展开更多
关键词 《毛泽东选集》 反讽修辞 译者 效果
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商业银行数字化转型如何影响风险承担——基于负债成本与信贷选择机制的分析 被引量:2
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作者 方芳 李强 《贵州财经大学学报》 北大核心 2024年第3期31-39,共9页
对于商业银行数字化转型如何影响其风险承担水平的研究,既有文献多从数字化场景下的信贷市场技术变化与授信模式调整切入,忽视了银行融资市场的影响。区别于此,本文通过商业银行的城市聚类,使用地区数字普惠金融指数作为地区性商业银行... 对于商业银行数字化转型如何影响其风险承担水平的研究,既有文献多从数字化场景下的信贷市场技术变化与授信模式调整切入,忽视了银行融资市场的影响。区别于此,本文通过商业银行的城市聚类,使用地区数字普惠金融指数作为地区性商业银行数字化转型程度的代理变量,利用城市商业银行2012—2022年面板数据,从“融”与“贷”两个维度分析商业银行数字化转型对风险承担的影响及其作用机制。实证结论表明:商业银行数字化转型显著增加了商业银行风险承担水平,且表现为信用风险(信贷不良率)与经营稳定性风险(收入波动性)的共同上升。机制分析表明,数字化转型的风险积累通过成本冲击效应而实现,信贷选择效应并不显著,说明商业银行数字化转型所形成的风险积累,实际源自“融”而非“贷”。商业银行缺乏通过信贷溢价释放负债成本压力的能力,导致负债成本的增加最终形成风险积累。此结论可为商业银行更为精准地选择风险控制与管理的业务切入口提供启示。 展开更多
关键词 数字化转型 风险承担 成本冲击效应 信贷选择效应
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氯酯磺草胺与甲咪唑烟酸复配防除香附子效果及对紫花苜蓿安全性
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作者 苏旺苍 杨慕菡 +3 位作者 薛飞 孙兰兰 徐洪乐 吴仁海 《草业科学》 CAS CSCD 北大核心 2024年第2期416-424,共9页
为明确氯酯磺草胺与甲咪唑烟酸应用于紫花苜蓿(Medicago sativa)田的可行性,在温室和田间测定了氯酯磺草胺和甲咪唑烟酸复配对香附子(Cyperus rotundus)的防效和紫花苜蓿的安全性。温室试验表明,氯酯磺草胺和甲咪唑烟酸复配对香附子具... 为明确氯酯磺草胺与甲咪唑烟酸应用于紫花苜蓿(Medicago sativa)田的可行性,在温室和田间测定了氯酯磺草胺和甲咪唑烟酸复配对香附子(Cyperus rotundus)的防效和紫花苜蓿的安全性。温室试验表明,氯酯磺草胺和甲咪唑烟酸复配对香附子具有很好的防除效果,两者按有效成分用量比1:2~1:4配比对香附子株高和鲜重的共毒系数分别介于131.54~150.46和152.84~180.25,呈明显增效作用,其中1:3的比例配伍的增效最为明显,对紫花苜蓿和香附子之间的株高和鲜重选择性指数分别为1.86和1.56。两地田间试验表明,氯酯磺草胺和甲咪唑烟酸(17.50+52.50)~(25.00+75.00) g·hm^(-2)复配处理对郑州和兰考两地的香附子株防效分别为78.5%~88.5%和82.1%~90.8%、鲜重防效分别为83.4%~92.7%和84.7%~93.6%,增产率分别为28.8%~35.1%和30.5%~38.3%,显著高于氯酯磺草胺和甲咪唑烟酸单用,且避免了单用氯酯磺草胺和甲咪唑烟酸的药害问题,提高了对紫花苜蓿的安全性,表明甲咪唑烟酸和氯酯磺草胺复配可有效防控香附子,对紫花苜蓿的安全性较好,具有良好推广应用前景。 展开更多
关键词 株高 鲜重 药害 防效 增效 共毒系数 选择性指数
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基于医院卫生技术评估的5种二肽基肽酶4抑制剂的临床应用情况
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作者 张俊珂 王晓娟 +2 位作者 鲁憬莉 张瑞 郝洁 《河南医学研究》 CAS 2024年第4期614-620,共7页
目的通过医院卫生技术评估(HB-HTA)对5种二肽基肽酶4抑制剂(DPP-4i)(西格列汀、维格列汀、沙格列汀、利格列汀和阿格列汀)进行评估,为医疗机构药品的遴选、临床的合理安全使用提供依据。方法通过HB-HTA,依照百分制评分体系,参考药品说... 目的通过医院卫生技术评估(HB-HTA)对5种二肽基肽酶4抑制剂(DPP-4i)(西格列汀、维格列汀、沙格列汀、利格列汀和阿格列汀)进行评估,为医疗机构药品的遴选、临床的合理安全使用提供依据。方法通过HB-HTA,依照百分制评分体系,参考药品说明书、临床指南和文献,从安全性、有效性、经济型、创新性、适宜性和可及性等方面分别对5种DPP-4i进行评估。结果西格列汀、维格列汀、沙格列汀、利格列汀和阿格列汀得分分别为85.0、75.0、77.0、80.0、78.5分。评分差异主要在安全性、经济性、适宜性和可及性方面。西格列汀综合得分最高。结论HB-HTA评估DPP-4i结果比较合理,为医院药品遴选、安全合理使用提供依据。 展开更多
关键词 医院卫生技术评估 药品遴选 二肽基肽酶4抑制剂 药品安全性 药品有效性
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基层中医药适宜技术遴选指标体系的构建
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作者 邢凯 许伟明 +2 位作者 刘陆阳 唐静 苏克雷 《世界中医药》 CAS 北大核心 2024年第16期2502-2507,共6页
目的:构建基层中医药适宜技术评价遴选指标体系。方法:对山东、四川等11个代表性省份进行调研和文献研究,收集、汇总已有的基层中医药适宜技术相关遴选指标体系;组织权威专家对既往基层中医药适宜技术相关遴选指标体系遴选维度和遴选指... 目的:构建基层中医药适宜技术评价遴选指标体系。方法:对山东、四川等11个代表性省份进行调研和文献研究,收集、汇总已有的基层中医药适宜技术相关遴选指标体系;组织权威专家对既往基层中医药适宜技术相关遴选指标体系遴选维度和遴选指标进行合并、增删等操作,初步得出基层中医药适宜技术相关遴选指标体系;组织专家开展初步遴选,收集专家对遴选指标体系的意见;组织15个省(区、市)开展正式遴选,收集各省份对遴选指标体系的建议。结果:从安全性、有效性、规范性、经济性、推广性5个维度构建了基层中医药适宜技术遴选指标体系,该遴选指标体系包括5个一级指标,12个二级指标和54个三级指标,且实现了量化评分。结论:本研究建立的基层中医药适宜技术遴选指标体系具有科学、系统和可操作性强等特点,可为基层中医药适宜技术的遴选提供参考工具。 展开更多
关键词 中医药 适宜技术 遴选 指标体系 基层 量化 安全性 有效性
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外用糖皮质激素引起的皮肤萎缩及其防治研究进展 被引量:2
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作者 杨丹丹 沈杰 +3 位作者 赵琪 王雍 孙振亮(综述) 胡振林(审校) 《中国美容医学》 CAS 2024年第1期181-184,共4页
皮肤萎缩是外用糖皮质激素最常见的副作用之一。外用糖皮质激素引起皮肤萎缩的机制包括:抑制角质形成细胞增殖、加快其分化成熟、抑制表皮脂质合成、抑制成纤维细胞增殖,减少胶原蛋白和透明质酸钠等细胞外基质合成等。近年来,对其副作... 皮肤萎缩是外用糖皮质激素最常见的副作用之一。外用糖皮质激素引起皮肤萎缩的机制包括:抑制角质形成细胞增殖、加快其分化成熟、抑制表皮脂质合成、抑制成纤维细胞增殖,减少胶原蛋白和透明质酸钠等细胞外基质合成等。近年来,对其副作用的防治主要集中在研发糖皮质激素受体的选择性调节剂、靶向抑制促萎缩基因及相关的信号通路、联合使用其他核受体的激动剂等方面,本文就其研究进展综述如下。 展开更多
关键词 糖皮质激素 皮肤萎缩 副作用 选择性调节剂 促萎缩基因 核受体激动剂
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6种除草剂对洋葱幼苗田间杂草防治效果及安全性评价
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作者 张仕林 陈微 +4 位作者 惠林冲 潘美红 李威亚 何林玉 杨海峰 《杂草学报》 2024年第1期62-70,共9页
为探究不同除草剂对洋葱幼苗田杂草的防效以及对洋葱幼苗生长发育的影响,并为除草剂在洋葱育苗田的安全使用提供依据,采用土壤和茎叶喷雾法,测定30%辛酰溴苯腈乳油(EC)、30%烯草酮EC、20%精喹禾灵EC、70%2,4-滴二甲胺盐水剂(AS)这4种苗... 为探究不同除草剂对洋葱幼苗田杂草的防效以及对洋葱幼苗生长发育的影响,并为除草剂在洋葱育苗田的安全使用提供依据,采用土壤和茎叶喷雾法,测定30%辛酰溴苯腈乳油(EC)、30%烯草酮EC、20%精喹禾灵EC、70%2,4-滴二甲胺盐水剂(AS)这4种苗后除草剂以及55%乙氧·异·甲戊EC和330 g/L二甲戊灵EC这2种土壤封闭除草剂对洋葱幼苗的室内安全性、田间除草效果及对生长的影响。结果表明,6种不同除草剂对洋葱幼苗的室内安全性存在差异,30%辛酰溴苯腈EC、30%烯草酮EC和20%精喹禾灵EC等3种药剂对洋葱幼苗无药害或只有极轻微药害,洋葱叶片和植株生长正常;70%2,4-滴二甲胺盐AS处理产生3级药害;55%乙氧·异·甲戊EC对出苗率影响小,后期幼苗生长健壮;330 g/L二甲戊灵EC对出苗率影响较大,并产生了1~2级的药害。6种不同除草剂对洋葱幼苗田间杂草株防效存在差异,30%辛酰溴苯腈EC药后35 d对灰绿藜和荠等双子叶的鲜重防效均高于90%,50 d对上述双子叶杂草的鲜重防效均高于70%;70%2,4-滴二甲胺盐AS对各类杂草的鲜重防效均较差;30%烯草酮EC和20%精喹禾灵EC对狗尾草、稗、菵草等禾本科杂草鲜重防效好,前者35 d内效果良好,后者更长效;55%乙氧·异·甲戊EC作为苗期封闭能够较好地抑制各类杂草的生长,35 d洋葱幼苗生长矮状,50 d洋葱幼苗生长较CK健壮;330 g/L二甲戊灵EC封闭抑制效果不及55%乙氧·异·甲戊EC,且对洋葱幼苗生长产生抑制,不宜使用。综上,用药量为1125 mL/hm 230%辛酰溴苯腈EC对双子叶杂草防效好,用药量分别为480、255 mL/hm 2的30%烯草酮EC、20%精喹禾灵EC对禾本科杂草防效好,用药量为1650 mL/hm 2的55%乙氧·异·甲戊EC可作为苗期封闭药使用,可起到安全较好的除草效果。 展开更多
关键词 洋葱幼苗 除草剂 安全性 除草效果 农艺性状
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苗前除草剂对江苏丘陵地区小麦田杂草防除效果和产量的影响
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作者 王晓琳 缪康 +5 位作者 于居龙 张国 张建华 束兆林 吴佳文 姚克兵 《杂草学报》 2024年第2期69-74,共6页
为筛选出适宜江苏丘陵地区小麦田高效封闭除草的药剂组合,设置3个单剂处理60%丙草·异丙隆可湿性粉剂150 g/667 m^(2)、60%丙草·异丙隆可湿性粉剂200 g/667 m^(2)、30%吡氟酰草胺悬浮剂30 mL/667 m^(2),3个两两混用药剂组合处... 为筛选出适宜江苏丘陵地区小麦田高效封闭除草的药剂组合,设置3个单剂处理60%丙草·异丙隆可湿性粉剂150 g/667 m^(2)、60%丙草·异丙隆可湿性粉剂200 g/667 m^(2)、30%吡氟酰草胺悬浮剂30 mL/667 m^(2),3个两两混用药剂组合处理60%丙草·异丙隆可湿性粉剂150 g/667 m^(2)+30%吡氟酰草胺悬浮剂20 mL/667 m^(2)、60%丙草·异丙隆可湿性粉剂150 g/667 m^(2)+30%吡氟酰草胺悬浮剂25 mL/667 m^(2)、60%丙草·异丙隆可湿性粉剂150 g/667 m^(2)+30%吡氟酰草胺悬浮剂30 mL/667 m^(2)和1个空白对照,于2022年在江苏丘陵地区开展小麦田间药效试验,测定不同土壤封闭除草剂及其组合对小麦田中杂草的防除效果及对小麦的安全性。结果表明,药剂组合处理对小麦田中的杂草防除效果明显高于单剂处理与空白对照,均在90%以上;且其产量也显著较高,均在400 kg/667 m^(2)以上。播后苗前选用60%丙草·异丙隆可湿性粉剂150 g/667 m^(2)+30%吡氟酰草胺悬浮剂20 mL/667 m^(2)进行土壤封闭处理,药后35、70、105 d对小麦田间总草的株防效均在93%以上,药后105 d对总草的鲜重防效在98%以上,与60%丙草·异丙隆可湿性粉剂150 g/667 m^(2)+30%吡氟酰草胺悬浮剂25 mL/667 m^(2)或30 mL/667 m^(2)组合处理差异不显著,且3个药剂组合处理均对小麦安全,对产量的影响无显著差异。因此,在江苏丘陵地区小麦田中宜选择60%丙草·异丙隆可湿性粉剂150 g/667 m^(2)+30%吡氟酰草胺悬浮剂20 mL/667 m^(2)组合进行土壤封闭除草,不仅对小麦安全,其防除小麦田一年生杂草的效果也较佳。 展开更多
关键词 小麦 除草剂 土壤封闭 防效 安全性
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