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三七皂甙对血管平滑肌上受体操纵Ca^(2+)通道的特异性作用(英文)

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中国药理学报 1994年第5期15卷 392-398页

作者：关永源关超然贺华孙家钧 edwin E DAnIEL 中山医科大学药理教研室 Department of Biomedical Sciences McMaster University Hamilton Ont L6N 3Z5 Canada

三七皂甙能明显抑制狗肠系膜动脉及大隐静脉α肾上腺素能受体触发的收缩反应及^(45)Ca内流(从0.36±0.03降至0.14±0.05μmol·g^(-1)组织湿重),但对高K^+引起的Ca^(2+)内流无影响。三七皂甙不影响Ca^(2+)释放及受体的亲和力。提示三七... 详细信息

三七皂甙能明显抑制狗肠系膜动脉及大隐静脉α肾上腺素能受体触发的收缩反应及^(45)Ca内流(从0.36±0.03降至0.14±0.05μmol·g^(-1)组织湿重),但对高K^+引起的Ca^(2+)内流无影响。三七皂甙不影响Ca^(2+)释放及受体的亲和力。提示三七皂甙具有特异性阻断受体操纵Ca^(2+)通道的特性,对电位依赖性Ca^(2+)通道无作用。

关键词：人参皂甙类血管平滑肌钙通道

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感应耦合非热等离子体催化转化二氧化碳（英文）

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Chinese Journal of Chemical Physics 2020年第2期 243-256页

作者： edwin Devid Maria Ronda-Lloret Qiang Huang Gadi Rothenberg n.Raveendran Shiju Aart Kleyn 中国工程物理研究院材料研究所可持续界面动力学研究中心荷兰阿姆斯特丹大学范特霍夫分子科学研究所重庆邮电大学光电工程学院

射频感应耦合等离子体能够在审温条件下选择活化并分解二氧化碳,本文通过调控等离子体放电条件(气体流量、放电频率等)获得了较高的一氧化碳产率.研究发现网状金属催化剂在二氧化碳等离子体中能促进氧原子的复合反应,从而有效抑制其与... 详细信息

射频感应耦合等离子体能够在审温条件下选择活化并分解二氧化碳,本文通过调控等离子体放电条件(气体流量、放电频率等)获得了较高的一氧化碳产率.研究发现网状金属催化剂在二氧化碳等离子体中能促进氧原子的复合反应,从而有效抑制其与目标产物一氧化碳的逆反应,提升反应整体效率.本文为实时转化过剩的可再生电能(来自太阳能、风能、潮汐能等)为高附加值一氧化碳中的化学能提供了一个可行的方案.

关键词：射频感应耦合等离子体等离子体反应器转换金属网四极质谱 X射线光电子能谱 X射线衍射扫描电子显微镜

Leafy Vegetables as Potential Pathways to Heavy Metal Hazards

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Journal of Agricultural Chemistry and Environment 2019年第1期8卷 23-32页

作者： C. E. Anarado C. J. O. Anarado M. O. Okeke C. E. Ezeh n. L. Umedum P. C. okafor Department of Pure and Industrial Chemistry Nnamdi Azikiwe University Awka Nigeria

The effect of anthropogenic activity relating to industrial and economic development has had a detrimental impact on the environment and human health, and hence the need for continued research. Five common African vegetables—Murraya koenigii, Ocimum gratissimum, Amaranthus hybridus, Capsicum annuum and Moringa oleifera were used to study absorption of Lead, Cadmium, Cobalt and Zinc from soils inoculated with metal ions. 0.1 M and 0.5 M solutions of the metal ions were used in the inoculation. Each of the plants was collected in the first instance at 8 weeks, and then at 10 weeks of inoculating. Atomic Absorption spectrophotometer was used to determine the metal ions concentrations absorbed in the plants. Cd2+ was most and Moringa oleifera the least absorbed of the four metal ions, with a highest value of 34.801 ± 0.805 mg/kg occurring in Capsicum annuum. Co2+ was the least absorbed of the four metal ions, Amaranthus hybridus showed highest absorption of Co2+ with mean absorption values of 5.566 ± 0.324 mg/kg and 5.670 ± 0.210 mg/kg for 0.1 M and 0.5 M solution of Co2+ respectively. Ocimum gratissimum absorbed Pb2+ most with the highest mean absorption of 5.290 ± 0.180 mg/kg and 6.354 ± 0.366 mg/kg for 0.1 M and 0.5 M respectively. Absorption increased as the concentration of the inoculant solution increased for all the plants, and decreased on moving from 8 weeks’ to 10 weeks’ for all the plants except Moringa oleifera. This could as a result of Phytovolatilization against the report of Padmavathiamma and Li, 2007 [1] that phytovolatilization occurs in As, Hg and Se. Ocimum gratissimum showed highest absorption with the mean value of 9.334 ± 0.312 mg/kg, when the inoculants concentration increased to 0.5 M, Capsicum annuum showed highest absorption with mean absorption value of 9.916 ± 0.614 mg/kg at 10th week. Also absorption increased as the concentration of the inoculant solution increased, and also on moving from 8 weeks’ to 10 weeks’ for all the plants. From th

关键词： Heavy Metals Ocimum gratissimum Murraya koenigii Capsicum annuum Amaranthus hybridus Moringa oleifera

Delineation of Shallow Aquifers of Umuahia and Environs, Imo River Basin, nigeria, Using Geo-Sounding Data

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Journal of Water Resource and Protection 2013年第11期5卷 1097-1109页

作者： Uchenna Ugada Alexander I. Opara Theophilus T. Emberga Frank D. Ibim Alexander I. Omenikoro edwin n. Womuru Department of Geosciences School of Sciences Federal University of Technology Owerri Nigeria Department of Physics Federal Polytechnic Nekede Owerri Nigeria Department of Physics Ignatius Ajuru University of Education Port Harcourt Nigeria

This work was undertaken to study the hydrogeophysical characteristics of Umuahia and environs,ImoRiver Basinusing geophysical data. Thirty (30) vertical electrical sounding data with a maximum electrode spacing of (AB/2) of 500 meters were acquired using the Schlumberger electrode configuration. The VES data were interpreted using the conventional partial curve matching technique to obtain initial model parameters, which were used as input for computer iterative modelling using the OFFIX software. The study revealed three (3) to six (6) geo-electric layers with underlying shale beds. Aquifer apparent resistivity in the study area ranges from about 50 to 850 Ωm with the aquifer depth varying between 0.53 - 82.67 m. Similarly, the aquifer thickness in the study area ranges from 0.8 - 110 m, with very low thicknesses around Ajata Ibeku. These shallow aquifers with very small thicknesses in the western areas around Ajata Ibeku are believed to be perched or fractured shale units with very low or no yield. Finally, transverse resistances in the study area range from 200 - 3400 Ωm2 with low values in the western part. Information extracted from iso-resistivity models, geoelectric cross sections, litho logs and electric logs revealed a sandy clay lithology at very shallow depths with a thick layer of shale/clay extending to over 300 m within the western part. These shallow aquiferous units are however perched, partially saturated and may not have sufficient yield. Finally, this study has helped to delineate the aquifers of the study into two distinct zones, thus revealing a groundwater divide.

关键词： Geo-Sounding Aquifer Units Resistivity Transverse Resistance Longitudinal Conductance nigeria

Unsustainable Land-Based Source Pollution in a Climate of Change: A Roadblock to the Conservation and Recovery of Elkhorn Coral <i>Acropora palmata</i>(Lamarck 1816)

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natural Resources 2014年第10期5卷 561-581页

作者： Geraldine Díaz-Ortega edwin A. Hernández-Delgado Center for Applied Tropical Ecology and Conservation Coral Reef Research Group University of Puerto Rico San Juan Puerto Rico Department of Biology University of Puerto Rico San Juan Puerto Rico Sociedad Ambiente Marino San Juan Puerto Rico Center for Applied Tropical Ecology and Conservation Coral Reef Research Group University of Puerto Rico San Juan Puerto Rico Department of Environmental Sciences University of Puerto Rico San Juan Puerto Rico Current Address: Instituto de Investigación e Ingeniería Ambiental Universidad de San Martín Buenos Aires Argentina

Chronic eutrophication and turbidity are critical detrimental factors impacting coral reef ecosystems, adversely affecting their ecological functions, services, benefits, and resilience across multiple spatial scales and over prolonged periods of time. Inadequate land use practices and lack of appropriate sewage treatment can adversely contribute to increase land-based source pollution (LBSP) impacts in coastal waters and to magnify impacts by sea surface warming trends associated to climate change. Fringing coral reefs off Vega Baja, Puerto Rico, support extensive remnant patches of Elkhorn coral Acropora palmata (Lamarck 1816), which was listed in 2006 as a threatened species under the US Endangered Species Act. Chronic impacts by LBSP have significantly affected local downstream fringing reefs. We characterized the spatial extent of a water quality stress gradient across 12 reefs along the Vega Baja coast through monthly measurements of multiple physico-chemical parameters. Most parameters, particularly PO4, , chlorophyll-a, and the concentration of optical brighteners (OABs), showed a statistically significant increase (PERMAnOVA, p n waters close to the main pollution sources, but also in waters adjacent to Cibuco River effluents. Dissolved oxygen also declined and turbidity increased on polluted sites. PO4, , and chlorophyll-a, exceeded recommended concentrations for coral reef ecosystems by factors of 7 - 50 times, 600 - 1240 times, and 17 - 83 times, respectively, depending on the source of the effluents and the distance from sewage pollution sources. Also, water turbidity exceeded 4 - 10 times the recommended value for pristine coral reefs. Coral reefs showed significant decline in close proximity to the polluted zone, showing a significantly different benthic community structure (PERMAnOVA, p nated by non-reef building taxa (i.e., macroalgae, algal turf) and bare substrate. Percent coral cover and abundance of A. palmata, showed a si

关键词： Acropora palmata Coral Reef Decline Eutrophication Land-Based Source Pollution

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相位测量的误差问题

相位测量的误差问题

Maize （Zea mays L.） Growth and Grain Yield under Conventional and Site-Specific nitrogen Management in a Dryland Farming System

作者： edwin n.Phillips 刘通阳

相比誤差模糊点的极限,不管是单个元件还是級联元件的,均能通过相应的列綫图迅速确定。要达到±1度的相位测量精度,困难来自諸元件的公差上。在微波领域內,由于复馈传輸系統的出現,使精确测量相位和幅度显得更为重要。但是,对于这样的測...

相比誤差模糊点的极限,不管是单个元件还是級联元件的,均能通过相应的列綫图迅速确定。要达到±1度的相位测量精度,困难来自諸元件的公差上。在微波领域內,由于复馈传輸系統的出現,使精确测量相位和幅度显得更为重要。但是,对于这样的測量,由于电路連結处和与此类似的不連續处难免要有失配,因而必定会碰到一个誤差范围問題。这个誤差范围利用普通的开槽綫式干涉仪能很好地分析判断出来。因为它是同时而不是相继地測定出相对的振幅和相位。所得結果,不仅适用于复馈传輸系統和一般的TEM同軸传輸設备,而且同样也适用于其它类型的传輸結构和系統。

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Journal of Agricultural Science and Technology(B) 2014年第8期4卷 602-611页

作者： Suzan Mashego Brilliant Mareme Petja Matshwene edwin Moshia Shadrack Batsile Dikgwatlhe Limpopo Department of Agriculture Directorate of Research Services Polokwane 0700 South Africa Department of Plant Production Soil Science andAgricultural Engineering University ofLimpopo Sovenga 0727 South Africa Department of Crop Science Tshwane University of Technology Pretoria 0001 South Africa College of Agronomy and Biotechnology China Agricultural University Beij'ing 100094 China

Large amount of pre-plant nitrogen （n） fertilizer results in low n use efficiency due to poor synchrony between soil n supply and maize n demand, especially during n sensitive growth stages. The objectives of the study were to compare growth and yield of maize （Zea rnays L.） under conventional and site-specific n management in a dryland farming system. The study, which was designed as randomized complete block design was conducted over three site-years under continuous maize cropping system in the semi-arid regions of the Limpopo Province in South Africa. Treatments of the study consisted of three n management strategies on a maize field planted to drought resistant SnK 2147 hybrid maize cultivar. Treatments were：（i） no n application （nO）, （ii） site-specific n at variable rates ranging between 18 kg n/ha and 33 kg n/ha based on soil analysis results （n l） and （iii） conventional and uniform n application broadcasted during planting at 58 kg n/ha （n2）. Sufficiency index as indication of n deficiency was determined using CCM-200 on maize leaves based on leaf numbers during maize vegetative growth stages V6, V10 and Vl4, and thereafter n was applied only when needed. The highest maize grain yield of 5.2 Mg/ha for n 1 was significantly higher （P 〈 0.05） than 3.2 Mg/ha and 4.0 Mg/ha of n0 and n2 in site-year I, respectively. Maize grain yield of 2.2 Mg/ha （nl） at site-year ll was significantly higher （P _〈 0.05） than 1.7 Mg/ha of the nO. The maize growth and yield under n2 and n1 was compared, n1 required between 43% and 69% lesser n fertilizer as compared to n2 over site-years, and resulted in higher maize height, number of leaves per plant, leaf length, and leaf area than that of conventional n management strategy. Therefore, site-specific n management strategy sustains and improves growth and yield of maize using minimal n fertilizer as compared to conventional approach in low fertility soils of semi-arid regions in dryland farming systems. In examining the results of

关键词： Africa maize grain yield nitrogen management precision agriculture

nutraceutical with Anti-Inflammatory Activity for the Management of Airway Remodeling in Bronchial Asthma: <i>Kalanchoe integra</i>Var. Crenata (Andr.) Cuf Leaf Extract

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Pharmacology & Pharmacy 2014年第3期5卷 250-261页

作者： Asiedu-Gyekye Isaac Julius Awortwe Charles nyamekye Effah Samuel Antwi Daniel Ansong Seidu Mahmood Adjei Samuel Banga n’guessan Benoit Kwame Amoateng Patrick nkansah edwin Department of Animal Experimentation Noguchi Memorial Institute for Medical Research College of Health Sciences Legon Ghana Department of Chemical Pathology School of Allied Health Sciences College of Health Sciences Korle-Bu Ghana Department of Pharmacology and Toxicology University of Ghana School of Pharmacy College of Health Sciences Legon Ghana Department of Physiology University of Ghana Medical School Col-lege of Health Sciences Korle-Bu Ghana Division of Pharmacology Faculty of Health Sciences University of Stellenbosch Cape Town South Africa

Background: Kalanchoe integra is widely used in folklore medicine as an antiasthmatic agent. Previous studies have shown the ameliorating effect of Kalanchoe integra leaf extract [KILE] on bronchial hyperesponsiveness and inflammation. Further, the stabilizing effect of Kalanchoe sp on mast cell degranulation, suggests that Kalanchoe species are suitable candidates for allergic asthma therapy. This study is designed to investigate the anti-asthmatic potential of KILE and monitor the accompanying histopathological and immunobiochemical changes that occur in an animal model of bronchial asthma using ovalbumin sensitized guinea pigs. Method: Thirty male guinea pigs were divided into five groups of six animals each. Bronchial asthma was simulated in guinea pigs using ovalbumin. Both low dose (300 mg/kg) and high dose extract (900 mg/kg) were administered daily for 42 days. Prednisolone (2.5 mg/kg) was the standard drug used. Results: Guinea pigs in all KILE treated groups maintained the integrity of their airway structures: bronchial folds and walls, alveoli, alveolar ducts and sacs. KILE and prednisolone caused a reduction in immune parameters (p 0.001), extent of bronchoconstriction, bronchial wall thickness and goblet cell accumulation in the sensitized guinea pigs. Conclusion: This study demonstrates the anti-asthmatic potential of KILE during prolonged administration by the oral route.

关键词： Kalanchoe Integra Asthma Bronchoconstriction Goblet Cells Perivascular Oedema

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葡萄酒抗氧化剂可以减少心脏病及癌症

山东食品发酵 1995年第3期 75-80页

作者： Andrew L.Waterhouse edwin n.Frandel 戴维斯加利福尼亚大学葡萄栽培及烯醇学系加利福尼亚大学食品科学及技术系加利福尼亚大学

葡萄酒的饮用可以解释法国的一些地方无法解释的心脏病发病率低的原因。这表明葡萄酒有保护心脏的功效。解释这个现象的一个理论是在葡萄酒中存在的酚类抗氧化剂抑制动脉粥样化的初级阶段——

关键词：葡萄酒抗氧化剂心脏病癌症防治作用

维普期刊数据库