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| 1 | Geochemical fractionation and ecological risks assessment of benthic sediment-bound heavy metals from coastal ecosystems off the Equatorial Atlantic Ocean显示文摘This study determines the pollution, fractionation, and ecological risks of sediment-bound heavy metals from coastal ecosystems off the Equatorial Atlantic Ocean. Contamination Factor(CF), pollution load index(PLI), and geoaccumulation index(Igeo) were used to assess the extent of the heavy metal pollution, while the potential ecological risk was evaluated using the risks assessment code(RAC) and Hkanson potential ecological risk. The analysis revealed concentrations(mg/g, dw) of the cadmium(Cd),chromium(Cr), copper(Cu), nickel(Ni), and lead(Pb) in sediments for wet and dry seasons vary from 4.40-5.08, 14.80-21.09. 35.03-44.8, 2.14-2.28, and 172.24-196.39, respectively. The results also showed that the metal fractionation percentages in the residual, oxidizable, and reducible fractions are the most significant, while the exchangeable and carbonate bound trace metals are relatively low. The RAC values indicate no risk for Cd and Ni and low risk for other metals at all the studied sites during both seasons.Potential ecological risk analysis of the heavy metal concentrations indicates that Cd had high individual potential ecological risk, while the other metals have low risk at all investigated sites. The multi-elemental potential ecological risk indices(R_1) indicate high ecological risk in all the ecosystems. | Nsikak U. Benson Essien D. Udosen Joseph P. Essien Winifred U. Anake Adebusayo E. Adedapo Oyeronke A. Akintokun Omowunmi H. Fred-Ahmadu Abass A. Olajire | 2017 | International Journal of Sediment Research2017，32，3： | 8 |
| 2 | Bioamendment of petroleum contaminated ultisol:effect on oil content, heavy metals and pH of tropical soil显示文摘The effect of organic amendments on the oil content, heavy metals concentration and pH of petroleum contaminated sandy loam ultisol obtained from Rumuekpe oil field in Emohua Local Government Area of Rivers State, Nigeria was determined. Petroleum contaminated soils were treated with wood ash, compost and sawdust. The addition of organic amendments resulted in a significant(at 95% probability level) decrease in oil content by 92% for composting, 81% for soil treated with sawdust and 58% for soil with ash supplementation, over 6 months. The effect of treatments on the iron(Fe), copper(Cu) and lead(Pb) concentration was significant at P <0 001. The remediation also affected the pH of soil. This initial pH of 5 6 was depressed by the application of compost and sawdust supplements respectively to a final pH of 5 2 and 5 3. On the other hand, amending the soil with wood ash raised the pH from 5 6 to 6 2. Increased acidity caused a decrease in the heavy metals concentration in the contaminated soil. Soil treatment with compost generally gave the best remediation results, followed by sawdust and then ash. Adjusting the pH of oil contaminated soil to high acidic levels may promote the availability and migration of heavy metals in remediated soils and not necessarily the rate of oil mineralization. | E. D. Udosen 1, J. P. Essien 2, R. M. Ubom 2 (1 Department of Chemistry and Biochemistry, University of Uyo, Nigeria 2 Department of Botany and Microbiology, University of Uyo, Nigeria) | 2001 | Journal of Environmental Sciences2001，13，1： | 5 |
| 3 | Distribution of actinomycetes in oil contaminated ultisols of the Niger Delta(Nigeria)显示文摘The distribution of actinomycetes in oil contaminated sandy loam ultisols of the Niger Delta region of Nigeria was studied to aid in understanding the effect of hydrocarbons on indigenous microbial population in tropical soils. The average total counts of actinomycetes in all the oil samples analysed was 10 3 cfu/g. Higher counts of actinomycetes were observed during the dry season than during the wet season. The counts of hydrocarbonoclastic actinomycetes correlated positively with the total count of actinomycetes. The actinomycetes were generally restricted to the top soil(0—10 cm soil depth) although a seemingly deeper(down to 40 cm soil depth) distribution was noticed in the dry season. The isolates included oil degrading species of Actinoplanes, Norcadia, Streptomyces and Streptosporangium. Their high oil utilization ability indicates their positive potential and role in the bioremediation of oil spilled soils. | J.P. Essien 1, E. D. Udosen 2 (1. Department of Microbiology, University of Uyo, Nigeria 2. Department of Chemistry and Biochemistry, University of Uyo,Nigeria) | 2000 | Journal of Environmental Sciences2000，12，3： | 2 |
| 4 | Antimalarial potency of the leaf extract of Aspilia africana(Pers.) C.D.Adams显示文摘Objective:To investigate the antimalarial activity of ethanol extract of Aspilin africana (A.africana) leaf.Methods:The ethanol extract of A.africana leaf(100-400 mg/kg) was screened for blood schizonticidal effect against chloroquine-sensitive Plasmodium berghei(P. berghei) in mice both in early and established models of antimalarial studies.Results:The leaf extract exhibited significant(P<0.05) antiplasmodial activity in 4-day early infection and in established infection tests with a considerable mean survival time comparable to that of standard drug,chloroquine(10 mg/kg).Conclusions:The findings show thai ethanol extract of A.africana leaf possesses potent antiplasmodial activity which justify the use in ethnomedicine and can be developed in malaria therapy. | Akuodor Godwin Christian Amos Grace Mfon Essien Augustine Dick Essien David-Oku Akpan Joseph Linus Ezeokpo Basil Chukwuma | 2012 | Asian Pacific Journal of Tropical Medicine2012，5，2： | 2 |
| 5 | Lead levels in Chromolaena odorata (Compositae) along rural and urban roads in Akwa Ibom State, Nigeria显示文摘Concentrations of lead(Pb) were determined in leaf samples of \%Chromolaena adorata\% from a rural road and an urban road in Akwa Ibom State of Nigeria in relation to vehicular traffic density. Mixed results were obtained wich no trend to indict automobile exhaust fumes. Lead was not detected in rain water from these areas and leaf lead levels seemed to relate more to soil lead concentrations. There was no significant difference in mean leaf lead levels between rural and urban leaf samples and between washed and unwashed leaf samples. It was suggested that the lack of concordance between vehicular traffic density and lead levels in leaves along the highways indicates either a low level use of tetraethyl leaded petrol or, a relatively low vehicular traffic density with lead from exhaust fumes not reaching a threshold to affect levels in plants or be detected in the atmosphere. Implications of concentrations obtained in leaves to consumers when compared with international standards were discussed. | Essien D. Udosen\+1, Okon M. Udodiong\+2 (1. Department of Chemistry and Biochemistry, University of Uyo, Nigeria 2.Department of Zoology, University of Uyo, Nigeria) | 1999 | Journal of Environmental Sciences1999，11，4： | 2 |
| 6 | Ethnobotanical survey of Akwa Ibom State of Nigeria显示文摘 | Kola′ K. Ajibesin Benjamin A. Ekpo Danladi N. Bala Etienne E. Essien Saburi A. Adesanya | 2007 | Journal of Ethnopharmacology2007，，3： | 2 |
| 7 | Geochemistry and organic petrography of Cretaceous sediments of the Calabar Flank, southeastern, Nigeria显示文摘 | B.O. Ekpo U.J. Ibok N. Essien H. Wehner | 2012 | Marine and Petroleum Geology2012，，1： | 1 |
| 8 | Knowledge,beliefs and attitudes about HIV/AIDS-related issues,and the sources of knowledge among health care professionals in southern Nigeria显示文摘 | Umeh CN Essien EJ Ezedinaehi EN | 2008 | J R Soc Health2008，128，5： | 1 |
| 9 | Chromatium species:an emerging bioindicator of crude oil pollution of tidal mud flats in the Niger Delta mangrove ecosystem,Nigeria显示文摘 | Essien J P Antai S P | 2008 | Environmental Monitoring and Assessment2008，135，14： | 1 |
| 10 | Coronary artery disease and the profile of cardiovascular risk factors in south nigeria:a clinical and autopsy study显示文摘 | Essien OE Andy J Ansa V | 2014 | Cardiol Res Pract2014，14，80： | 1 |
| 11 | Knowledge, beliefs and attitudes about HIV/AIDS - related issues, and the sources of knowledge among health care professionals in southern Nigeria, 显示文摘 | Umeh CN Essien EJ Ezedinachi EN | 2008 | J R Soc Health2008，128，5： | 1 |
| 12 | In vitro antiplasmodial activity of crude extracts from Togolese medicinal plants显示文摘Objective:To investigate the antimalarial effect of a few plants in Togo folk medicine. Methods:After ethnobotanical survey,Opilia celtidifolia,Pavetta corymbosa(P.corymbosa) and Tamarindus indica(T.indica) were selected for screening.In vitro antimalarial tests were performed on crude extracts against fresh clinical isolates of Plasmodium falciparum using the semi microtest.Results:Different IC50,values of the extracts ranged from 2.042 to 100.000μg/mL. According to the results,the methanol extract of aerial part of P.corymbosa followed by aqueous extract of fruit of T.indica were the most active(IC50 of 2.042 and 4.786μg/mL,respectively). Qualitative test revealed the presence of alkaloids in the leaves of P.corymbosa that may be responsible for the activity of the plant.Conclusions:Our study provides scientific evidence for usage of plant in the folk medicine,and further studies are needed for identification and purification of the active principles. | Koffi Koudouvo Simplice D.Karou Denise P.Ilboudo Kouami Kokou Kodjo Essien Kodjo Aklikokou Comlan de Souza Jacques Simpore Mensavi Gbeassor | 2011 | Asian Pacific Journal of Tropical Medicine2011，4，2： | 1 |
| 13 | Knowledge,beliefs and attitudes about HIV/AIDS related issues,and the sources of knowledge among health care professionals in southern Nigeria显示文摘 | Chiamaka N Umeh E James Essien | | 0，，05： | 1 |
| 14 | Beam characterization of a materials processing CO2 laser显示文摘 | Fuerschbach P W | 1996 | Welding Journal1996，75，2： | 1 |
| 15 | Knowledge, beLiefs and attitudes about HIV/AIDS related issues, and the sources of knowledge among health care professionals in southern Nigeria 显示文摘 | Chiamaka N Umeh E James Essien | 2008 | J R Soc Heath2008，128，5： | 1 |
| 16 | Heavy metal transfer to vegetables from contaminated farmland sdloining sub urban animal park/ marke Uyo 显示文摘 | Essien O E Douglass E E | 2012 | African Journal of Agricultural Research2012，7，8： | 1 |
| 17 | Sermons] variation in admission for heart failure, hypertension and stroke in UYO, South - Eastern Nigeria 显示文摘 | Arma V Ekott J Essien IO | 2008 | Annals of African Medicine2008，7，： | 1 |
| 18 | Antiplasmodial and analgesic activities of Clausena anisata显示文摘Objective:Antiplasmodial and analgesic activities of the leaf extract and fractions of Clausena anisata(C.anisata) were evaluated for antimalarial and analgesic activities.Methods:The crude leaf extract(39-117mg/kg) and fractions(chloroform and acqeous;78mg/kg) of C. anisata were investigated for antiplasmodial activity against chloroquine-sensitive Plasmodium berghei(P.berghei) infections in mice using suppressive,prophylactic and curative models and analgesic activity against acetic acid,formalin and heat-induced pains.Artesunate,5 mg/kg and pyrimethamine,1.2mg/kg were used as positive controls.Thin films made from tail blood of each mouse were used to assess the level of parasitaemia of the mice.Results:The extract and its fractions dose-dependently reduced parasitaemia induced by chloroquine-sensitive P.berghei in prophylactic,suppressive and curative models in mice.These reductions were statistically significant(P<0.001).They also improved the mean survival time(MST) from 17 to 21 days relative to control(P<0.01-0.001).On chemically and thermally-induced pains,the extract inhibited acetic acid and formalin-induced inflammation as well as hot plate-induced pain in mice.These inhibitions were statistically significant(P<0.001) and in a dose-dependent fashion. Conclusions:The antiplasmodial and analgesic effects of this plant may in part be mediated through its chemical constituents and it can be concluded that the C.anisata possess significant antimalarial and analgesic properties. | Jude E Okokon Ette O Etebong John A Udobang Grace E Essien | 2012 | Asian Pacific Journal of Tropical Medicine2012，5，3： | 1 |
| 19 | Antiretroviral therapyrefusal among newly diagnosed HIV-infected adults显示文摘 | Katz IT Essien T Marinda ET | 2011 | AIDS2011，25，17： | 1 |
| 20 | Testicular cancer incidence trends in the USA (1975–2004): plateau or shifting racial paradigm?显示文摘 | L. Holmes C. Escalante O. Garrison B.X. Foldi G.O. Ogungbade E.J. Essien D. Ward | 2007 | Public Health2007，，9： | 1 |
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