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Registros recuperados: 2.860 | |
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Pereira,Alexandre Igor Azevedo; Ramalho,Francisco de Sousa; Bandeira,Catarina de Medeiros; Malaquias,José Bruno; Zanuncio,José Cola. |
Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) was exposed to gammacyhalothrin to study the stimulatory effect of low concentrations of this pyrethroid. The doses studied were 23.4375, 11.7188, 5.8594, 2.9297, 1.4648, 0.7324 mg.litre-1 and water, as control. The third, fourth, and fifth instars of P. nigrispinus were shorter with all the doses of this insecticide. The survival and longevity of this predator was highest with the lowest doses. The oviposition period of P. nigrispinus decreased as the doses increased. The lowest pre-and postoviposition periods were found with 11.7188 mg.litre-1 of gammacyhalothrin. The dose 0.7324 mg.litre-1 increased the clutch interval. The egg viability was similar between the treatments. The number of eggs per... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Predator; Pyrethroid; Stink bug; Hormesis; Biology. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132009000500013 |
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Bezerra,Stephane Flaviane de Oliveira; Costa,Ludimila de Araújo; Freitas,Priscylla Alves Nascimento de; Oliveira,Naila Francis Paulo de. |
The purpose of this study was to investigate the effect of aging on the DNA methylation status of two genes involved in tumorigenesis (telomerase gene hTERT and DNA repair gene- MLH1) and one in metabolism (methylenetetrahydrofolate reductase gene- MTHFR) in oral epithelial cells. DNA methylation analysis was performed by Methylation Sensitive Restriction Enzymes (MSRE) of healthy oral epithelial cells of child (6-10 years, n=21), young (20-25 years, n=19) and elderly (over 60 years, n=25). The results for the hTERT gene showed significant variation in the methylation frequency at CpG dinucleotides among the groups (p=0.0001), with the methylated condition more frequently in children and young people. In relation to MLH1 and MTHFR, no differences were... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Epigenetic; DNA methylation; Aging; DNA repair; Telomerase; MTHFR. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132015000100082 |
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Mattos,José Carlos Pelielo de; Motta,Ellen Serri da; Oliveira,Márcia Betania Nunes de; Dantas,Flávio José da Silva; Araujo,Adriano Caldeira de. |
Reactive oxygen species (ROS) can induce lesions in different cellular targets, including DNA. Stannous chloride (SnCl2) is a ROS generator, leading to lethality in Escherichia coli (E. coli), with the base excision repair (BER) mechanism playing a role in this process. Many techniques have been developed to detect genotoxicity, as comet assay, in eukaryotic cells, and plasmid DNA agarose gel electrophoresis. In this study, an adaptation of the alkaline gel electrophoresis method was carried out to ascertain the induction of strand breaks by SnCl2 in bacterial DNA, from E. coli BER mutants, and its repair pathway. Results obtained show that SnCl2 was able to induce DNA strand breaks in all strains tested. Moreover, endonuclease IV and exonuclease III play... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Alkaline gel electrophoresis; Escherichia coli; Base excision repair; Stannous chloride; DNA strand breaks; Reactive oxygen species. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000700020 |
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Fernandes,Mileni da Silva; Iano,Flávia Godoy; Rocia,Vivian; Yanai,Marcela Mitsuko; Leite,Aline de Lima; Furlani,Tatiana Almeida; Buzalaf,Marília Afonso Rabelo; Oliveira,Rodrigo Cardoso de. |
The aim of this study was to compare the effect of fluoride (F) on alkaline phosphatase activity in the liver and plasma of the rats. Four groups of male Wistar rats (n=6), which received drinking water containing 5, 15 or 50 ppm F or deionized water (control) throughout the experiment were included in the study. The animals were euthanized and had their tissues and blood plasma collected for the analysis of fluoride and alkaline phosphatase. There was an increase in F concentration in most tissues in the animals treated with higher F concentrations, except for the heart. The alkaline phosphatase assay showed an increase in the activity in the liver and blood plasma of the animals treated with fluoride concentrations of 15 and 50 ppm (p<0.05). This... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Alkaline phosphatase; Fluoride; Liver; Kidney. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132011000600014 |
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Cortez,Lucia Elaine Ranieri; Ferreira,Izabel Cristina Piloto; Lonardoni,Valdrinez Campana; Ferreira,Antonio Gilberto; Vieira,Paulo Cesar; Silva,Maria Fátima das Graças Fernandes da; Fernandes,João Batista; Cortez,Diógenes Aparicio Garcia. |
The dichloromethane extract of Almeidea coerulea stems yielded the (11-hydroxyrutaecarpine alkaloid reported for the first time from this species) and the triterpene (28-hydroxy-28, 29-dihydrolupeol). The dictamine, skimianine, sitosterol and stigmasterol were also isolated from methanol extract. Extracellular forms of Leishmania amazonensis (promastigotes) was tested with dichloromethane extract and 28-hydroxy-28, 29-dihydrolupeol with showed anti-leishmanial activity above 0.1 mg/mL and 75µg/mL (inhibited 50% promastigote growth), respectively. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Almeidea coerulea; Rutaceae; Indolopyridoquinazoline alkaloid; Anti-leishmanial activity. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132011000100008 |
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Barbosa,Elizabeth Gorgone; Pivello,Vânia Regina; Meirelles,Sérgio Tadeu. |
The aim of this study was to look for evidence of allelochemicals in B. decumbens, in parts of the plant from where they could easily be released to the environment. The germination inhibition of Phalaris canariensis, Lactuca sativa (standard species) and Melinis minutiflora, another invasive African grass, was tested using B. decumbens germinating seeds and aqueous leachates of the roots, green and senescent leaves, at 5, 10 and 20% w/v. Both the germinating seeds and the aqueous leachates of B. decumbens reduced the germination of the species tested; the effectiveness of the aqueous leachates increased according to concentration. Apparently, the competitive advantage of B. decumbens in the cerrados could be amplified via allelopathy. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allelopathy; Cerrado; Biological invasion; Brachiaria decumbens; Melinis minutiflora. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000400021 |
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Peres,Marize Terezinha Lopes Pereira; Mapeli,Ana Maria; Faccenda,Odival; Gomes,Alcir Teixeira; Honda,Neli Kika. |
Environmental degradation caused by the excessive use of pesticides has motivated studies aimed at the discovery of new formulations for pest control. The bioassays carried out under laboratory conditions for the present study involved the germination and seedling growth of Lactuca sativa cv. Grand Rapids and Allium cepa cv. Baia Periforme treated with lecanoric acid or one of seven esters obtained from the alcoholysis of the acid. Each substance was tested at concentrations of 10-3, 10-5, 10-7 M, and 10-9 M. The results revealed that, except for lecanoric acid and methyl orsellinate, all other compounds exhibited significant differences in their action when compared with the controls. Also, A. cepa was more sensitive to the compounds assayed, at the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allelopathy; Germination; Growth; Lactuca sativa; Allium cepa; Orsellinates. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132009000400027 |
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Meda,Anderson R.; Cassiolato,Marcelo E.; Pavan,Marcos A.; Miyazawa,Mário. |
A laboratory experiment was conducted to evaluate the effects of water soluble plant extracts on soil acidity. The plant materials were: black oat, oil seed radish, white and blue lupin, gray and dwarf mucuna, Crotalaria spectabilis and C. breviflora, millet, pigeon pea, star grass, mato grosso grass, coffee leaves, sugar cane leaves, rice straw, and wheat straw. Plant extracts were added on soil surface in a PVC soil column at a rate of 1.0 ml min-1. Both soil and drainage water were analyzed for pH, Ca, Al, and K. Plant extracts applied on the soil surface increased soil pH, exchangeable Ca ex and Kex and decreased Al ex. Oil seed radish, black oat, and blue lupin were the best and millet the worst materials to alleviate soil acidity. Oil seed radish... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Plant residue; Organic material; Leaching. |
Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132001000200012 |
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Afonso,Ana Adelina de O.; Henry,Raoul; Rodella,Rita C.S.Maimoni. |
In two streches of the Itaúna stream, one in a gallery forest and the other in an herbaceous vegetation zone, litter matter input (sorted by leaves, ligneous and reproductive components) were measured during a year. In the gallery forest stretch, the direct input and lateral transport attained 713 g.m-2.year-1 and 421 g.m-1. year-1, respectively. In contrast, the herbaceous vegetation stretch showed a direct litter input and lateral transport of only 86 g.m-2.year-1 and 124 g.m-1. year-1, respectively. The empoverishment of riparian vegetation had a significant effect on the decrease of allochthonous input to stream mainly by direct input. Peaks of direct input into Itaúna stream occurred during late dry season and in the early wet season. They were... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allochthonous input; Stream; Riparian vegetation. |
Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132000000300014 |
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Ramachandran,Sumitra; Patel,Anil K.; Nampoothiri,Kesavan Madhavan; Chandran,Sandhya; Szakacs,George; Soccol,Carlos Ricardo; Pandey,Ashok. |
Solid-state fermentation was carried out for the production of alpha-amylase using Aspergillus oryzae. Different oil cakes such as coconut oil cake (COC) sesame oil cake (SOC), groundnut oil cake (GOC), palm kernel cake (PKC) and olive oil cake (OOC) were screened to be used as substrate for the enzyme production and also compared with wheat bran (WB). GOC was found to be the best producer of the enzyme among these. Combination of WB and GOC (1:1) resulted higher enzyme titres than the individual substrates. Maximum amount of enzyme (9196 U/gds) was obtained when SSF was carried out using WB + GOC, having initial moisture of 64% and supplemented with lactose and ammonium nitrate (1% each) at 30ºC for 72h using 2 mL spore suspension (6x10(7)spores/ml).... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Alpha amylase; Oil cakes; Solid-state fermentation; Partial purification; Aspergillus oryzae. |
Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132004000200019 |
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Fracácio,Renata; Verani,Nelsy Fenerich; Espíndola,Evaldo Luiz Gaeta; Rocha,Odete; Rigolin-Sá,Odila; Andrade,Cássio Arilson. |
The objective of this work was to assess the toxicity of sediment samples from six cascade reservoirs in Tietê river system, in São Paulo State, Brazil, through chronic-partial toxicity bioassays with Danio rerio larvae as test-organisms. Histology of gills and biometric measurements were used to determine the existence of toxicity problems. The alterations on gill morphology here detected were considered of first stage (hyperplasia, lamellar junction and excess of mucous cells) in the first reservoirs and very slight in the last ones. The biometric analysis pointed to inadequate conditions for the growth of the test-organisms when exposed to the sediment of the rivers and upstream reservoirs and also indicated an improvement of environmental conditions... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Gill morphology; Sediment toxicity; Danio rerio; Tietê reservoirs; Pollution. |
Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132003000400023 |
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Registros recuperados: 2.860 | |
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