|
|
|
Registros recuperados: 61 | |
|
|
Mendes, Rodrigo de Souza; UFCG; Silva, Aderbal Marcos de Azevêdo; UFCG; Silva, Guilherme de Lira Sobral; UFCG; Nóbrega, Giovanna Henriques da; UFCG; Lôbo, Katiuscia Menezes; UFCG; Pereira Filho, José Morais; UFCG. |
Este trabalho teve por objetivo determinar as exigências líquidas de zinco (Zn), cobre (Cu) e ferro (Fe) de cordeiros Santa Inês em pastejo na região semiárida. Os animais com peso vivo entre 20 e 30 kg apresentaram conteúdo corporal no peso de corpo vazio (PCV) para esses minerais de 60,26 a 76,37 mg kg-1, 10,78 a 16,72 mg kg-1 e 133,44 a 126,98 mg kg-1, respectivamente. Observou-se que com o aumento do PCV, as concentrações de Cu e Zn também aumentavam, enquanto a de Fe diminuía. As exigências líquidas para cordeiros em regime de pastejo variaram de 1,69 a 7,86 mg dia-1 para Cu e 7,20 a 27,4 mg dia-1 para Zn. Os resultados obtidos no presente trabalho, para exigências desses minerais, foram maiores do que as exigências dietéticas recomendadas pelo do NRC... |
Tipo: Pesquisa de campo |
Palavras-chave: Zootecnia composição corporal; Exigências nutricionais; Ferro; Cobre; Zinco; Exigências dietéticas Zootecnia body composition; Nutritional requirements; Iron; Copper; Zinc; Dietary requirements. |
Ano: 2010 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAnimSci/article/view/5883 |
| |
|
| |
|
| |
|
| |
|
| |
|
| |
|
|
Hernandez,Pedro P; Undurraga,Cristian; Gallardo,Viviana E; Mackenzie,Natalia; Allende,Miguel L; Reyes,Ariel E. |
Copper is an essential ion that forms part of the active sites of many proteins. At the same time, an excess of this metal produces free radicals that are toxic for cells and organisms. Fish have been used extensively to study the effects of metals, including copper, present in food or the environment. It has been shown that different metals induce different adaptive responses in adult fish. However, until now, scant information has been available about the responses that are induced by waterborne copper during early life stages of fish. Here, acute toxicity tests and LC50 curves have been generated for zebrafish larvae exposed to dissolved copper sulphate at different concentrations and for different treatment times. We determined that the larvae... |
Tipo: Journal article |
Palavras-chave: Acute exposure; Apoptosis; Copper; Early life stage; Heat shock; Protein-70; Zebrafish. |
Ano: 2011 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602011000100002 |
| |
|
|
DELGADO,RICARDO; VERGARA,CECILIA; WOLFF,DANIEL. |
Based on indirect evidence, a role for synaptically released copper and zinc as modulators of neuronal activity has been proposed. To test this proposal directly, we studied the effect of copper, zinc, and other divalent cations on voltage-dependent currents in dissociated toad olfactory neurons and on their firing rate induced by small depolarizing currents. Divalent cations in the nanomolar range sped up the activation kinetics and increased the amplitude of the inward sodium current. In the micromolar range, they caused a dose dependent inhibition of the inward Na+ and Ca2+ currents (I Na and I Ca) and reduced de amplitude of the Ca2+-dependent K+ outward current (I Ca-K). On the other hand, the firing rate of olfactory neurons increased when exposed to... |
Tipo: Journal article |
Palavras-chave: Copper; Zinc; Modulators; Channels; Neuronal excitability. |
Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602006000100019 |
| |
|
|
Arakaki,Andréa Haruko; Souza Vandenberghe,Luciana Porto de; Soccol,Vanete Thomaz; Masaki,Ryu; Rosa Filho,Ernani Francisco da; Gregório,Alexsandro; Soccol,Carlos Ricardo. |
The objective of this work was to study the production of biomass with copper bioaccumulation in submerged fermentation using sugarcane molasses. Candida pelliculosa BARU 05 isolated from Baru (Dipteryx alata) was selected for its good capacity to accumulate the copper. Fermentation was carried out using the medium composed by sugarcane molasses at 5 °Brix enriched with (g/L) CuSO4.5H2O 0.1; yeast extract, 10.0; (NH4)2SO4, 5.0 ; KH2PO4, 5.0 MgSO4, 0.5, inoculum 10 % of total volume (100 ml), pH 6.0, and incubation at 30 °C, 120 rpm for 120 h. After three steps of optimization an uptake of 95.04% and 13.397 g/L biomass were obtained. The kinetics of copper bioaccumulation and biomass production was followed in a 10- liter bioreactor in a batch and fed-batch... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bioaccumulation; Baru; Yeast; Copper; Sugarcane molasses. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132011000500021 |
| |
|
| |
|
|
Spitzner,Reinaldo. |
The author presents an analytic process for copper quantitative determination in mineral and potable waters, based in the reaction of the cation copper with sodium diethyl-dithio carbamate. Due to the presence of certain elements common in water, such as iron, calcium, magnesium, etc., the main principles of the reactions behavior were studied. In the same manner the reaction sensibility was verified, as well as its precision, by the addition of known quantities of copper. About the end of the work presented, there are shown some copper determinations made through the mentioned process with mineral and potable waters of Paraná. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Copper; Photometry; Mineral waters. |
Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132001000500004 |
| |
|
|
Palacio,Soraya Moreno; Espinoza-Quiñones,Fernando Rodolfo; Galante,Raquel Manozzo; Zenatti,Dilcemara Cristina; Seolatto,Araceli Aparecida; Lorenz,Evandro Kleber; Zacarkim,Carlos Eduardo; Rossi,Nickeli; Rizzutto,Márcia de Almeida; Tabacniks,Manfredo Harri. |
The present work was performed using the common onion (Allium cepa L.) as a bioindicator of toxicity of heavy metals in river water. The test waters were collected at two sampling sites: at the beginning and the end of the Toledo River. The bulbs of A. cepa L. were grown in test water with nine concentration levels of copper, zinc and lead from 0.1 to 50 ppm. In the laboratory, the influence of these test liquids on the root growth was examined during five days. For test liquids containing below 0.03-ppm dissolved Cu the root growth was reduced by 40% However, the same reduction occurred for 1-ppm dissolved Zn. For dissolved Pb, results reveal toxicity above 0.1 and 0.6 ppm at the beginning and the end of the Toledo river water, respectively. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Acute toxicity; Bioassay; Copper; Zinc; Lead; Allium cepa L. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132005000400024 |
| |
|
| |
|
|
Dengfeng,WANG; Haijie,HUANG; Huande,FENG; Hua,WANG; Miaojie,HAN; Zhiping,QI. |
ABSTRACT This research aimed to discover the distribution and the primary influence factors of Cu in the soil-rice systems of tropical farmland. Soil samples of farmland and rice plant (stalk and polished rice) from the western region of Hainan Island were collected and studied. The results showed that the average Cu content in the topsoil of the study area was 15.75 mg kg-1; the highest Cu content (45.92 mg kg-1) was found in the rice fields of the northern area, where pyroclastic parent material is distributed. Thus, there is a potential for Cu contamination of the rice grown in this region. The average contents of Cu in the rice stalks and polished rice were 16.9 and 5.68 mg kg-1, respectively, indicating that the stalks had a larger capacity for Cu... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Rice; Copper; Arable land; Hainan. |
Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132016000200703 |
| |
|
| |
|
|
Souza,Patrícia Mendes de; Marinho,Petrusk Homero; Lima,Marcos Antônio Barbosa de; Nascimento,Aline Elesbão do; Takaki,Galba Maria de Campos. |
The aim of this work was to evaluate the physiological aspects of polyphosphate metabolism of Cunninghamella elegans grown in presence of copper. The growth profile was obtained by means of biomass yields, orthophosphate consumption, polyphosphate accumulation and phosphatases activities. The results revealed the influence of copper on the growth, observed by biomass yields. Orthophosphate consumption was faster in cells grown in the presence of copper. The presence of copper in the culture medium induced polyphosphate accumulation. The polyphosphate level was almost constant in the beginning of control culture growth, and could be related to the exponential growth phase. On the other hand, the copper treated cultures exhibited a significant reduction in... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cunninghamella elegans; Copper; Polyphosphate; Phosphatases. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822005000400002 |
| |
|
|
Paolicchi,F.; Perea,J.; Cseh,S.; Morsella,C.. |
To study the deficiency of minerals and its relationship with Paratuberculosis, blood, serum, and fecal samples were obtained from 75 adult bovines without clinical symptoms of the disease and from two bovines with clinical symptoms of the disease, from two beef herds with a previous history of Paratuberculosis in the Province of Buenos Aires, Argentina. Serum samples were processed by ELISA and feces were cultured in Herrolds medium. Copper, zinc and iron in serum were quantified by spectrophotometry and selenium was measured by the activity of glutathione peroxidase. We also determined copper, zinc, iron and molybdenum concentrations in pastures and the concentration of sulfate in water. Mycobacterium avium subsp paratuberculosis (Map) was isolated from... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Paratuberculosis; Micronutrients; Selenium; Molybdenum; Copper. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822013000100022 |
| |
|
| |
|
|
Choudhary,Sikander P.; Bhardwaj,Renu; Gupta,Bishan D.; Dutt,Prabhu; Gupta,Rajinder K.; Kanwar,Mukesh; Dutt,Pitamber. |
The present study determined the effects of copper and chromium metals on the endogenous titers of polyamines, auxins, abscisic acid and antioxidative enzyme activities in Raphanus sativus L. cv. Pusa chetki seedlings. Among polyamines, putrescine and spermidine contents were enhanced by Cu2+ metal to 62.44 and 402.8 µg g-1 f.w. respectively over control. Spermine which was not observed in control was recorded in highest concentration (1287.9 µg g-1 f.w.) in Cu2+ metal stressed seedlings. On the other hand Cr6+ metal treated seedlings showed reduced contents of putrescine (1.43 µg g-1 f.w.), cadaverine (0.09 µg g-1 f.w.), spermidine (277.99 µg g-1 f.w.) and spermine (2.29 µg g-1 f.w.) when compared to control and Cu2+ metal treated seedlings. Significant... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Catalase; Chromium; Copper; Guaiacol peroxidase; Polyamines (PAs); Superoxide dismutase. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202010000400006 |
| |
|
|
Ducic,Tanja; Polle,Andrea. |
Heavy metals like Mn and Cu, though essential for normal plant growth and development, can be toxic when present in excess in the environment. For normal plant growth maintenance of metal homeostasis is important. Excess uptake of redox active elements causes oxidative destruction. Thus, uptake, transport and distribution within the plant must be strongly controlled. Regulation includes precisely targeted transport from the macro-level of the tissue to the micro-level of the cell and organelles. Membrane transport systems play very important roles in metal trafficking. This review provides a broad overview of the long distance and cellular transport as well as detoxification and homeostasis mechanisms of Mn and Cu, which are essential micronutrients but... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Copper; Heavy metals; Manganese; Phytoremediation; Transport. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000100009 |
| |
Registros recuperados: 61 | |
|
|
|