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Registros recuperados: 80 | |
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Adamis,Paula D.B.; Panek,Anita D.; Leite,Selma G.F.; Eleutherio,Elis C.A.. |
At the concentration used in this work (10 ppm), cadmium was efficiently removed from the environment by stationary yeast cells. While exponential phase cells showed low capacity of cadmium absorption, stationary cells removed 97% of the original metal in 24 hours. Total cadmium absorption shown by dry cells was lower than that of fresh ones, although both cells removed 50% of metal during the first hour of treatment. We also verified that only viable cells were capable of absorbing cadmium. Independently of the growth phase, cells showed high tolerance to 10 ppm CdSO4 and about 80% of cells remained viable after 24 hours exposure to cadmium. However, when stationary phase cells were previously dehydrated and then exposed to cadmium, they exhibited poor... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Saccharomyces cerevisiae; Cadmium; Absorption; Intracellular oxidation. |
Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822003000100012 |
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Alkmim Filho,J. F.; Germano,A.; Dibai,W.L.S.; Vargas,E.A.; Melo,M.M.. |
The aim of this study was to investigate the presence of arsenic, lead and cadmium residues in samples of liver, kidney and muscle of poultry and swine during the years from 2002 to 2008. A total of 1978 samples were analyzed: 1031 of poultry and 947 of swine from Brazilian slaughterhouses. The samples were analyzed at the National Agricultural Laboratory using the atomic absorption spectrometry technique. In poultry, the arsenic residues were detected in 53.6% of liver samples, although no results have exceeded the MRL. In kidneys, 39.7% of the samples showed measurable residues and there was no violation of the limits. Regarding lead, there were 5 contaminated liver samples and 24 contaminated kidney samples (1.5 and 3.6% respectively). In muscle tissue... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Trace elements; Arsenic; Cadmium; Lead. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352014000200022 |
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Baffard, Vincent. |
Différents travaux menés depuis 1984 chez l'huître creuse en particulier, montrent qu'i existe, dans les branchies (Thiriot-Quiévreux C., 1982), une certaine proportion de cellules possédant un nombre de chromosomes inférieur au nombre habituel 2N=20. Ce phénomène est l'aneuploïdie. Cette anomalie cytogénétique est mise en évidence par un comptage de chromosomes d'une suspension cellulaire obtenue à partir de branchies. Il est apparu que le taux d'aneuploïdie affectait négativement les taux de croissance (Leitao & al. 2001). Il existe deux types d'origines possibles à l'aneuploïdie. La première peut être génétique (Leitao & al. 2001), et la seconde environnementale. L'effet de l'atrazine sur l'aneuploïdie a déjà fait l'objet de travaux. Il existe... |
Tipo: Text |
Palavras-chave: Génétique; Aneuploïdie; Huître creuse; Crassostrea gigas; Mercure; Cadmium; Atrazine; Impact. |
Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/00033/14405/11698.pdf |
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Benavides,María P.; Gallego,Susana M.; Tomaro,María L.. |
Heavy metals are important environmental pollutants and their toxicity is a problem of increasing significance for ecological, evolutionary, nutritional, and environmental reasons. Plants posses homeostatic cellular mechanisms to regulate the concentration of metal ions inside the cell to minimize the potential damage that could result from the exposure to nonessential metal ions. This paper summarizes present knowledge in the field of higher plant responses to cadmium, an important environmental pollutant. Knowledge concerning metal toxicity, including mechanisms of cadmium homeostasis, uptake, transport and accumulation are evaluated. The role of the cell wall, the plasma membrane and the mycorrhizas, as the main barriers against cadmium entrance to the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cadmium; Heavy metals; Metal toxicity; Phytochelatins; Oxidative stress. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000100003 |
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Bouilly, Karine; Gagnaire, Beatrice; Bonnard, Marc; Thomas-guyon, Helene; Renault, Tristan; Miramand, Pierre; Lapegue, Sylvie. |
Pacific oysters, Crassostrea gigas, are commonly reared in estuaries where they are exposed to anthropogenic pollution. Much research has been made on the toxicity of cadmium to aquatic organisms because the compound recurrently contaminates their environment. Our study examined the influence of cadmium on aneuploidy level (lowered chromosome number in a percentage of somatic cells) and hemocyte parameters in C. gigas at different stages of life. Adults and juveniles were exposed to two different concentrations of cadmium. The first concentration applied was equivalent to a peak value found in Marennes-Oleron bay (Charente-Maritime, France; 50 ng L-1) and the second was 10 times higher (500 ng L-1). Exposure to 50 ng L-1 cadmium caused a significant... |
Tipo: Text |
Palavras-chave: Phenoloxidase; Flow cytometry; Hemocytes; Aneuploidy; Crassostrea gigas; Cadmium. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1687.pdf |
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Bouilly, Karine; Leitao, Alexandra; Mccombie, Helen; Miramand, Pierre; Lapegue, Sylvie. |
Aneuploidy is the alteration of the normal diploid chromosome number. In the Pacifie oyster, Crassastrea gigas, hypodiploid cells have regularly been reported as have a negative correlation between this phenomenon and growth and evidence for a genetic basis. We previously demonstrated a positive relationship between a pollutant, atrazine, and aneuploidy in Crassastrea gigas adults and juveniles. To evaluate the persistence of this impact, the present study focused on a sample of the same juveniles previously exposed to different atrazine treatments (0.0 1 mg/l which represents a peak value found in a polluted environment and 0.1 mg/l) for three and a half months. Then, we evaluated them for aneuploidy after another two and a half months in non polluted... |
Tipo: Text |
Palavras-chave: Cadmium; Atrazine; Pollutant; Pacific oyster; Aneuploidy. |
Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/acte-2852.pdf |
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Chakravorty, R.; Van Grieken, R.. |
The coprecipitation of Cd, Co and Eu from seawater onto ferric hydroxide was studied, using the radioactive tracers <sup>109</sup>Cd, <sup>60</sup>Co and <sup>152-154</sup>Eu, as a function of the pH, the concentration of the collector iron, the concentration of the metal spike and the aging of the internally formed precipitate. For preconcentration purpose, a pH 9 and a 35 ppm iron concentration appeared to be suitable. At pH 8, the natural pH of seawater, the distribution coefficients for Cd, Co and Eu are 10<sup>4.5</sup>, 10<sup>5</sup> and 10<sup>7</sup>, respectively. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cadmium; Coprecipitation; Radiochemistry; Sea water. |
Ano: 1986 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3236 |
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Chouba, L.; Mzougui-Aguir, N.. |
Dans l’objectif de déterminer l’état de la contamination organique et inorganique des sédiments superficiels de la frange côtière du golfe de Gabès, nous avons évalué les concentrations en hydrocarbures aromatiques totaux, en cadmium (Cd), en plomb (Pb) et en mercure (Hg). L’échantillonnage a été effectué à bord d’une barque motorisée, à l’aide d’une benne Van Veen au niveau de 25 stations. Les concentrations du Cadmium et du Plomb ont été déterminées par Spectrométrie d’Absorption Atomique à Four Graphite (Varian 220Z) alors que pour le Mercure les analyses ont été réalisées par Spectrométrie d’Absorption Atomique à vapeur froide. Les hydrocarbures totaux ont été analysés par UV-Fluorescence (UV-F). Les concentrations du Cadmium et du Mercure dans la... |
Tipo: Journal Contribution |
Palavras-chave: Cadmium; Coastal waters; Hydrocarbons; Lead; Marine pollution; Mercury; Pollution monitoring; Sediments; Trace metals. |
Ano: 2006 |
URL: http://hdl.handle.net/1834/4275 |
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Dange, Catherine. |
Most of trace elements have a non conservative behavior in estuarine environments. It is the case of cadmium, cobalt and caesium for which the fate in estuarine and coastal zones is largely controlled by their distribution between water and suspended particles, which generally have high residence times or can be definitely deposited in these areas. Metallic contaminants and radionuclides can be present under various species : dissolved (mineral and organic complexes), colloidal and particulate forms (adsorbed, precipitated) or integrated by various mechanisms in the organisms. Such distributions are the result of processes (physical, chemical, biological) which are controlled by many factors (ionic strengh, pH, Eh, major cations concentration, nature and... |
Tipo: Text |
Palavras-chave: Modeling; French estuaries; Caesium; Cobalt; Cadmium; Radionuclides; Trace metals; Speciation; Modélisation; Estuaires français; Cesium; Cobalt; Cadmium; Radionucléides; Métal trace; Speciation. |
Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/2002/these-183.pdf |
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Registros recuperados: 80 | |
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