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Registros recuperados: 240 | |
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Alvarez,María De Los Angeles; Zarelli,Valeria E. P.; Pappano,Nora B.; Debattista,Nora B.. |
In previous work the bacteriostatic action of trihydroxylated chalcones against Staphylococcus aureus ATCC 25 923 was investigated. In this work the action of 2´,4´,2-(OH)3-chalcone, 2´,4´,3-(OH)3- chalcone and 2´,4´,4-(OH)3 -chalcone against Escherichia coli ATCC 25 922 was evaluated. Growth kinetic curves of E.coli were made in nutritive broth added with increasing drug concentrations. The specific growth rates of the microorganisms were calculated by a kinetic turbidimetric method, which was previously probed and the minimal inhibitory concentrations (MIC´s) were evaluated by a mechanism of action proposed. The MICs of 2´,4´,3-(OH)3-chalcone and 2´,4´,2-(OH)3-chalcone were 46 mg/ml and 122 mg/ml, respectively. The 2´,4´,4-(OH)3-chalcone was inactive.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chalcones; Bacteriostatic Activity; Hydroxylation. |
Ano: 2004 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452004000100004 |
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Céccoli,Gabriel; Ramos,Julio C.; Ortega,Leandro I.; Acosta,Juan M.; Perreta,Mariel G.. |
Chloris gayana Kunth is a grass species valuable as forage which was introduced into Argentina to be used as pasture in saline soils of subtropical and warm-temperate zones, given its good adaptability to drought, salinity and mild freezing. However, its tolerance varies according to the cultivar. In tetraploid cultivars, important reductions in yield have been observed. Here, a study of the variations produced on the root and stem system by salinity at different NaCl concentrations (0, 150 y 250 mM) was performed in the Boma cultivar, with the aim of determining the anatomical and morphological alterations produced by the salt excess. Plants cultivated with the highest level of salinity showed, in the whole, significant differences in the measured... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Abiotic stress; Tolerance; Vascular tissue. |
Ano: 2011 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452011000100002 |
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Shi,Jianli; Mei,Wenyan; Yang,Jing. |
As the key component of many hemoproteins (heme-containing proteins), heme is involved in a broad range of biological processes. Enzymes required for heme biosynthesis and degradation pathways are evolutionarily conserved. While heme metabolism has been studied extensively, the expression of heme metabolism enzymes during development has not been described. Here, we report that all heme biosynthases and two heme oxygenases, which initiate heme degradation, are dynamically expressed during Xenopus embryonic development. All heme synthases, with the exception of aminolevulinic acid synthase 2, are maternally expressed. At neurula stage, heme synthases are expressed in the developing neural tissue and in migrating neural crest cells. At the swimming tadpole... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Heme synthases; Heme oxygenases; Development; Xenopus. |
Ano: 2008 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452008000300007 |
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Chen,Feng; Chen,Xiang-Ming; Chen,Zhi; Jiang,Han-Liang; Pan,Xiao-Ping; Hu,Zhong-Rong; Liu,Rong-Hua; Chen,Xiao-Ming. |
We want to construct a yeast expression system for thymosin a1 (Ta1) to make the orally administered Ta1 preparation possible. The whole Ta1 DNA fragment was obtained by PCR. After being digested with restriction enzymes, it was cloned into pYES2 vector. Sequencing was performed to identify the recombinant. The sequence of Ta1 in recombinant coincided with the original one reported in Genbank. When pYES2-Ta1 plasmid was transformed into yeast, galactose instead of glucose was used to induce Ta1 expression. Western blot was performed to identify the quality of the expressed Ta1. Dried yeast containing pYEST2-Ta1 was fed to Balb/c mice whose immunities were inhibited by cyclophosphamide in advance. Synthesized Ta1 peptide was used as positive control and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Thymosin a1; Yeast expression system; Biological activity; Orally administered. |
Ano: 2005 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452005000300002 |
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Pires Bione,Nilton Cesar; Suely Pagliarini,Maria; Alves de Almeida,Leones. |
A spontaneous male-sterile, female-fertile mutation affecting bivalent arrangement at the metaphase plate and cytokinesis was detected in line BR98-197 of the soybean breeding program developed by Embrapa - National Soybean Research Centre. Untill diakinesis, meiosis was normal with chromosome pairing as bivalents. From this phase, in several meiocytes, bivalents were not able to organize a single metaphase plate and remained scattered in the cytoplasm in a few or several groups. In these meiocytes, chromosomes segregated in both divisions giving rise to several micronuclei. However, the main cause of male sterility was the absence of cytokinesis after telophase II. Instead of the typical tetrads of microspores, four nucleate coenocytic microspores were... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Glycine max; Meiosis; Metaphase plate; Cytokinesis; Male sterility. |
Ano: 2005 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452005000200004 |
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Silva-Briano,Marcelo; Martínez-Hernández,Sandra Luz; Adabache-Ortíz,Araceli; Ventura-Juárez,Javier; Salinas,Eva; Quintanar,J. Luis. |
Syntaxin-1 and 25-kDa Synaptosome-associated Protein (SNAP-25) are present in the plasma membrane of several different secretory cell types and are involved in the exocytosis process. In this work, the free-living amoeba Difflugia corona was studied in relation to ultrastructure, structural membrane proteins, and proteins such as Syntaxin-1 and SNAP-25. Our results obtained by scanning electron microscopy in the amoeba without its theca, showed many membrane projections and several pore-like structures. Using immunocytochemistry, we found structural proteins Syntaxin-1 and SNAP-25. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Amoeba; Membrane proteins; Pore-like; Theca; Ultrastructure. |
Ano: 2007 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452007000200004 |
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Victoriano,Eliane; Gregório,Elisa A.. |
The Lyonet's gland is found in Lepidoptera larvae, close to the excretory duct of the silk gland. The role played by this gland is still uncertain. This work aims to describe the ultrastructure of the Lyonet's gland in Diatraea saccharalis larvae, offering suggestions regarding its possible function. The insects were reared under laboratory-controlled conditions. The glands were conventionally prepared for transmission (TEM) and scanning (SEM) electron microscopy. SEM showed that Lyonet's glands are paired small structures located in the ventral side of the head. They are composed by clustered long cells resembling leaves. Under TEM observations, each cell is surrounded by a thin basal lamina and contains large stellate nucleus. The cytoplasm presents... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Accessory gland; Insect; Sugarcane borer; Morphology. |
Ano: 2004 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452004000200006 |
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Registros recuperados: 240 | |
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