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MORPHOLOGICAL, CYTOLOGICAL, AND CULTURAL ASPECTS OF CURVULARIA PALLESCENS Rev. Microbiol.
Freire,Sônia Valéria Pereira; Paiva,Laura Mesquita; Lima,Elza Aúrea de Luna-Alves; Maia,Leonor Costa.
Curvularia pallescens Boedijn (Hyphomycetes) is redescribed with the aid of a scanning electron microscope, and the optimal cultural conditions for growing this fungus are discussed. Cytological analysis and nuclear condition, observed through the HCl-Giemsa technique, showed vegetative and reproductive structures (hypha and conidia) formed by uni, bi, tri, and multinucleated segments. Cultures of C. pallescens in Complete medium and in Potato dextrose agar varied on growth, on aspects of the border of the colonies and also on medium pigmentation. The Complete medium and the temperature between 25-28°C were the most indicated for growth of C. pallescens.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Conidial development; Fungi; Electron microscopy; Hyphomycetes.
Ano: 1998 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37141998000300010
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Boron affects the growth and ultrastructure of castor bean plants Scientia Agricola
Silva,Denis Herisson da; Rossi,Monica Lanzoni; Boaretto,Antonio Enedi; Nogueira,Neusa de Lima; Muraoka,Takashi.
The cultivation of oleaginous plants like the castor bean guarantees employment for agricultural families and can contribute in energy and chemical sectors, especially in the northeastern semi-arid regions of Brazil. Boron (B) deficiency is a widespread nutritional disorder despite the fact that various anthropogenic sources with high B content may increase soil B to toxic levels for plants. The present study was designed to investigate the ultrastructural effects of boron deficiency and toxicity on castor bean plants which were grown under greenhouse condition using plastic containers with 10 L of nutrient solution. Boron treatments comprised: control (no B); 0.27 mg L-1, 5.40 mg L-1 B pots (one plant per pot), tested in a completely randomized design...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Electron microscopy; Middle lamellae; Micronutrient; Xylem; Starch.
Ano: 2008 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162008000600014
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Silicon and rice disease management Trop. Plant Pathol.
Rodrigues,Fabrício A; Datnoff,Lawrence E.
The element silicon (Si) is not considered an essential nutrient for plant function. Nevertheless, Si is absorbed from soil in large amounts that are several fold higher than those of other essential macronutrients in certain plant species. Its beneficial effects have been reported in various situations, especially under biotic and abiotic stress conditions. The most significant effect of Si on plants, besides improving their fitness in nature and increasing agricultural productivity, is the restriction of parasitism. There has been a considerable amount of research showing the positive effect of Si in controlling diseases in important crops. Rice (Oryza sativa), in particular, is affected by the presence of Si, with diseases such as blast, brown spot and...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Mechanisms of host resistance; Electron microscopy; PR-genes; Phenolic-like compounds; Phytoalexins.
Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-41582005000500001
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Cytopathological characterization of Mal de Río Cuarto virus in corn, wheat and barley Trop. Plant Pathol.
ARNEODO,JOEL D.; LORENZO,EUGENIA; LAGUNA,IRMA G.; ABDALA,GUILLERMINA; TRUOL,GRACIELA A..
The Mal de Río Cuarto disease is caused by Mal de Río Cuarto virus (MRCV) transmitted by Delphacodes kuscheli. Comparative studies were carried out on the cytopathological alterations produced by MRCV in corn (Zea mays), wheat (Triticum aestivum) and barley (Hordeum vulgare), as seen with a transmission electron microscope. Corn plants were infected with viruliferous D. kuscheli collected from the endemic disease area (i.e. Río Cuarto County, Córdoba, Argentina). For the viral transmission to small grain cereal plants, laboratory rared insects were used. In this case, the inoculum source was wheat and barley plants infected with MRCV isolate grown in a greenhouse. Leaf samples with conspicuous symptoms were collected: enations and size reduction in corn;...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Virus characterization; Electron microscopy; Fijivirus; Reoviridae; Cereals.
Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-41582002000300010
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Detection and coat protein gene characterization of an isolate of Grapevine virus B from corky bark-affected grapevines in Southern Brazil Trop. Plant Pathol.
NICKEL,OSMAR; FAJARDO,THOR V. M.; ARAGÃO,FRANCISCO J. L.; CHAGAS,CÉSAR M.; KUHN,GILMAR B..
An isolate of Grapevine virus B (GVB), obtained by indexing Vitis labrusca and V. vinifera grapevines on the indicator LN33, was transmitted mechanically to several Nicotiana species. The virus was partially purified from N. cavicola and the coat protein estimated at 23 kDa by SDS-PAGE. In negatively stained leaf extracts of experimentally inoculated N. cavicola and N. occidentalis, flexuous particles with cross banding were observed, predominantly measuring 750-770 x 12 nm, with a modal length of 760 nm. Decoration indicated a clear, positive reaction against AS-GVB. In DAS-ELISA, GVB was detected in N. cavicola and grapevine extracts, and Western blots showed homologous and cross reaction of GVB and GVA antisera with GVB coat protein. Using specific...
Tipo: Info:eu-repo/semantics/article Palavras-chave: GVB; Vitis spp.; Vitivirus; Electron microscopy; ELISA; Western blot; GVA.
Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-41582002000300007
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Coat protein and RNAs of Cole latent virus are not present within chloroplasts of Chenopodium quinoa-infected cells Trop. Plant Pathol.
Belintani,Priscila; Gaspar,José O..
Cole latent virus (CoLV), genus Carlavirus, was studied by electron microscopy and biochemical approaches with respect both to the ultrastructure of the Chenopodium quinoa infected cells and to its association with chloroplasts. The CoLV was observed to be present as scattered particles interspersed with membranous vesicles and ribosomes or as dense masses of virus particles. These virus particles reacted by immunolabelling with a polyclonal antibody to CoLV. Morphologically, chloroplasts, mitochondria and nuclei appeared to be unaltered by virus infection and virus particles were not detected in these organelles. However, virus particle aggregates were frequently associated with the outer membrane of chloroplasts and occasionally with peroxisomes....
Tipo: Info:eu-repo/semantics/article Palavras-chave: Brassica; Electron microscopy; Carlavirus; Virus replication; Plant virus.
Ano: 2003 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-41582003000100012
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Nutritious tissue in petals of Annonaceae and its function in pollination by scarab beetles Acta Botanica
Gottsberger,Gerhard; Webber,Antonio Carlos.
ABSTRACT The feeding of pollinating dynastid-scarab beetles on nutritious tissue of Annonaceae flowers results in macroscopically visible gnawing marks on petals. In the present paper, we present and discuss examples of such gnawing marks on Annonaceae from the Cerrado and the Amazon Forest in Brazil. The localization of gnawing marks on the petals and the histochemistry of the nutritious tissues are emphasized. In some species, nutritious tissue is apparently distributed among all petals, while in other species it is more or less diffusely localized. There are also cases in which nutritious tissue occurs only on clearly localized regions of the inner petals. Petals of selected Amazon species were stained, and studied by light and scanning electron...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cerrado and Amazon forest Annonaceae; Electron microscopy; Histochemistry; Lipids; Mucilage cells in petals; Starch; Tannins.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062018000200279
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Interconnection between microstructure and microhardness of directionally solidified binary Al-6wt.%Cu and multicomponent Al-6wt.%Cu-8wt.%Si alloys Anais da ABC (AABC)
VASCONCELOS,ANGELA J.; KIKUCHI,RAFAEL H.; BARROS,ANDRÉ S.; COSTA,THIAGO A.; DIAS,MARCELINO; MOREIRA,ANTONIO L.; SILVA,ADRINA P.; ROCHA,OTÁVIO L..
An experimental study has been carried out to evaluate the microstructural and microhardness evolution on the directionally solidified binary Al-Cu and multicomponent Al-Cu-Si alloys and the influence of Si alloying. For this purpose specimens of Al-6wt.%Cu and Al-6wt.%Cu-8wt.%Si alloys were prepared and directionally solidified under transient conditions of heat extraction. A water-cooled horizontal directional solidification device was applied. A comprehensive characterization is performed including experimental dendrite tip growth rates (VL) and cooling rates (TR) by measuring Vickers microhardness (HV), optical microscopy and scanning electron microscopy with microanalysis performed by energy dispersive spectrometry (SEM-EDS). The results show, for...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Solidification; Metals and alloys; Electron microscopy; Hardness.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652016000301099
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Dermocystidium sp. in the gills of farmed Oreochromis niloticus in Brazil Anais da ABC (AABC)
STECKERT,LILIAN D.; CARDOSO,LUCAS; TANCREDO,KAREN R.; MARTINS,MAURÍCIO L.; JERÔNIMO,GABRIELA T..
Abstract: The genus Dermocystidium is very comprehensive in the host and site of infection, however this is the first report of the occurrence of Dermocystidium sp. in the gills of Nile tilapia. This study was carried out in a fish farming located in the state of Santa Catarina, Brazil. No mortalities were reported in the facility studied and the animals were clinically healthy. During the histopathological analysis of the gills, 8.33% of the fish presented spores of Dermocystidium sp. in the gill tissue. The spores reported herein had a mean length and width of 6.206 x 5.233 μm and a refractile body diameter of 1.965 μm and were studied by histopathology and Transmission Electron Microscopy. This study highlights the importance of a new branchial pathogen...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Fish farming; Dermatocystidiosis; Nile tilapia; Histology; Electron microscopy; Spores.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000500865
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Correlative microscopy of Purkinje cells Biocell
Castejón,Orlando J..
The Purkinje cell and their synaptic contacts have been described using (1) light microsocopy, (2) transmission and scanning electron microscopy, and freeze etching technique, (3) conventional and field emission scanning electron microscopy and cryofracture methods, (4) confocal laser scanning microscopy using intravital stain FM64, and (5) immunocytochemical techniques for Synapsin-I, PSD9-5, GluR1 subunit of AMPA receptors, N-cadherin, and CamKII alpha. The outer surface and inner content of plasma membrane, cell organelles, cytoskeleton, nucleus, dendritic and axonal processes have been exposed and analyzed in a three-dimensional view. The intramembrane morphology, in bi- and three-dimensional views, and immunocytochemical labeling of synaptic contacts...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cerebellar cells; Synaptic contacts; Electron microscopy; Immunohistochemistry.
Ano: 2012 URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452012000100001
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Natural infection of Viola cornuta (Violaceae) with Cucumber mosaic virus, subgroup I Biocell
Arneodo,Joel; de Breuil,Soledad; Lenardon,Sergio; Conci,Luis.
Plants of Viola cornuta displaying typical virus symptoms were observed during spring 2003 in a plant nursery in Córdoba, central Argentina. Electron microscopic examinations of symptomatic leaf samples revealed the presence of isometric virus-like particles about 30 nm in diameter. Subsequent serological analysis allowed the identification of the pathogen as a subgroup I strain of Cucumber mosaic virus (CMV). These results were confirmed by antigen capture - reverse transcription - polymerase chain reaction with specific CMV primers, and digestion with a restriction enzyme. This is the first report of CMV infecting V. cornuta in Argentina.
Tipo: Info:eu-repo/semantics/other Palavras-chave: Viola cornuta; Cucumber mosaic virus; Electron microscopy; Serology; AC-RT-PCR.
Ano: 2005 URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452005000200008
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Sperm ultrastructure of Mytella (Bivalvia) populations from distinct habitats along the northern coast of São Paulo State, Brazil Biocell
Orlandi Introíni,Gisele; Martins Maester,Fernanda; Pedini Pereira Leit,Fosca; Recco-Pimentel,Shirlei Maria.
Ultrastructural analyses of bivalve spermatozoa are relevant in studies that aim to identify taxonomic traits for the purposes of discriminating species and conducting phylogenetic studies. In the present work, spermatozoa of mussel specimens of the genus Mytella, collected from two populations living in distinct habitats, were examined by electron microscopy. The objective was to identify sperm ultrastructural taxonomic traits that could be used to differentiate Mytella species. The specimens were from populations that live in intertidal zones on the southeast coast of Brazil, either buried in muddy-sand sediment or anchored to rocky substrates. The acrosomal vesicle was conical and long, the axial rod extended from the nucleus to the acrosome, the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Mytilidae; Spermatozoa; Electron microscopy; Mussel.
Ano: 2010 URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452010000300002
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Extracellular breakdown of collagen by mice decidual cells. A cytochemical and ultrastructural study Biocell
Godosevicius Katz,Sima.
The interaction of antimesometrial decidual cells and collagen fibrils was studied by light microscopy and ultrastructural cytochemistry in fed and acutely fasted mice on days 9-11 of pregnancy. Fibrillar elements in the extracellular space consisted of collagen fibrils and filamentous aggregates (disintegrating collagen fibrils). Intracellular vacuoles exhibited typical collagen immersed in electron-translucent material (clear vacuoles) and faint cross-banded collagen immersed in electron-opaque material (dark vacuoles). Fibrillar elements showed extracellular acid phosphatase activity which was stronger in the region of mature decidua than in predecidual cells region in all animals; it was conspicuous in mature decidua of fasted animals. Intracellular...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Decidua; Acid phosphatase; Fasting; Electron microscopy; Mice.
Ano: 2005 URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452005000300003
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Ultrastructural changes of the olfactory bulb in manganese-treated mice Biocell
Villalobos,Virginia; Bonilla,Ernesto; Castellano,Alan; Novo,Ernesto; Caspersen,Ralph; Giraldoth,Debora; Medina-Leendertz,Shirley.
The effect of manganese toxicity on the ultrastructure of the olfactory bulb was evaluated. Male albino mice were injected intraperitoneally with MnCl2 (5 mg/Kg/day) five days per week during nine weeks. The control group received NaCl (0.9%). The olfactory bulbs of five mice from each group were processed for transmission electron microscopy after 2, 4, 6 and 9 weeks of manganese treatment. On week 2, some disorganization of the myelin sheaths was observed. After 4 weeks, degenerated neurons with dilated cisternae of rough endoplasmic reticulum and swollen mitochondria appeared. A certain degree of gliosis with a predominance of astrocytes with swollen mitochondria, disorganization of the endomembrane system, dilation of the perinuclear cisternae and...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Metal toxicity; Toxicity; Neurodegeneration; Electron microscopy.
Ano: 2009 URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452009000300007
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Quantitative analysis of nucleolar chromatin distribution in the complex convoluted nucleoli of Didinium nasutum (Ciliophora) Biol. Res.
Leonova,Olga G; Karajan,Bella P; Ivlev,Yuri F; Ivanova,Julia L; Skarlato,Sergei O; Popenko,Vladimir I.
We have earlier shown that the typical Didinium nasutum nucleolus is a complex convoluted branched domain, comprising a dense fibrillar component located at the periphery of the nucleolus and a granular component located in the central part. Here our main interest was to study quantitatively the spatial distribution of nucleolar chromatin structures in these convoluted nucleoli. There are no "classical" fibrillar centers in D.nasutum nucleoli. The spatial distribution of nucleolar chromatin bodies, which play the role of nucleolar organizers in the macronucleus of D.nasutum, was studied using 3D reconstructions based on serial ultrathin sections. The relative number of nucleolar chromatin bodies was determined in macronuclei of recently fed, starved...
Tipo: Journal article Palavras-chave: 3D reconstruction; Ciliates; Electron microscopy; Macronucleus; Nucleoli.
Ano: 2013 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602013000100010
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Modeling pulmonary fibrosis by abnormal expression of telomerase/apoptosis/collagen V in experimental usual interstitial pneumonia BJMBR
Parra,E.R.; Pincelli,M.S.; Teodoro,W.R.; Velosa,A.P.P.; Martins,V.; Rangel,M.P.; Barbas-Filho,J.V.; Capelozzi,V.L..
Limitations on tissue proliferation capacity determined by telomerase/apoptosis balance have been implicated in pathogenesis of idiopathic pulmonary fibrosis. In addition, collagen V shows promise as an inductor of apoptosis. We evaluated the quantitative relationship between the telomerase/apoptosis index, collagen V synthesis, and epithelial/fibroblast replication in mice exposed to butylated hydroxytoluene (BHT) at high oxygen concentration. Two groups of mice were analyzed: 20 mice received BHT, and 10 control mice received corn oil. Telomerase expression, apoptosis, collagen I, III, and V fibers, and hydroxyproline were evaluated by immunohistochemistry, in situ detection of apoptosis, electron microscopy, immunofluorescence, and histomorphometry....
Tipo: Info:eu-repo/semantics/article Palavras-chave: BHT experimental model; Usual interstitial pneumonia; Alveolar epithelial cell apoptosis; Telomerase activity; Collagen V; Electron microscopy.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2014000700567
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Ultrastructural study of the neovagina following the utilization of human amniotic membrane for treatment of congenital absence of the vagina BJMBR
We present an ultrastructural study of the utilization of human amniotic membrane in the treatment of congenital absence of the vagina in 10 patients. All patients were surgically treated with application of an amniotic membrane graft using the modified McIndoe and Bannister technique. Sixty days after surgery, samples of the vaginal neo-epithelium were collected for transmission electron microscopy analysis. The ultrastructural findings consisted of a lining of mature squamous epithelium indicating the occurrence of metaplasia of the amniotic epithelium into the vaginal epithelium. The cells were arranged in layers as in the normal vaginal epithelium, i.e., superficial, intermediate and deep layers. There were desmosomes and cytoplasmic intermediate...
Tipo: Info:eu-repo/semantics/other Palavras-chave: Amniotic membrane; Amnion; Electron microscopy; Congenital absence of vagina; Neovagina.
Ano: 1997 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000700007
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Diversity among satellite glial cells in dorsal root ganglia of the rat BJMBR
Nascimento,R.S.; Santiago,M.F.; Marques,S.A.; Allodi,S.; Martinez,A.M.B..
Peripheral glial cells consist of satellite, enteric glial, and Schwann cells. In dorsal root ganglia, besides pseudo-unipolar neurons, myelinated and nonmyelinated fibers, macrophages, and fibroblasts, satellite cells also constitute the resident components. Information on satellite cells is not abundant; however, they appear to provide mechanical and metabolic support for neurons by forming an envelope surrounding their cell bodies. Although there is a heterogeneous population of neurons in the dorsal root ganglia, satellite cells have been described to be a homogeneous group of perineuronal cells. Our objective was to characterize the ultrastructure, immunohistochemistry, and histochemistry of the satellite cells of the dorsal root ganglia of 17 adult...
Tipo: Info:eu-repo/semantics/other Palavras-chave: Satellite glial cells; Peripheral nervous system; Vimentin; S-100; Electron microscopy.
Ano: 2008 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2008001100011
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Radioautographology: the proposal of a new concept BJMBR
Nagata,T..
A new concept termed "radioautographology" is advocated. This term was synthesized from "radioautography" and "ology", expressing a new science derived from radioautography. The concept of radioautographology (RAGology) is that of a science whose objective is to localize radioactive substances in the biological structure of objects and to analyze and study the significance of these substances in the biological structure. On the other hand, the old term radioautography (RAG) is the technique used to demonstrate the pattern of localization of various radiolabeled compounds in specimens. The specimens used in biology and medicine are cells and tissues. They are fixed, sectioned and placed in contact with the radioautographic emulsions, which are exposed and...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Light microscopy; Electron microscopy; Radioautography; Technique; Application.
Ano: 1998 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1998000800001
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Effect of melatonin and time of administration on irradiation-induced damage to rat testes BJMBR
Take,G.; Erdogan,D.; Helvacioglu,F.; Göktas,G.; Ozbey,G.; Uluoglu,C.; Yücel,B.; Guney,Y.; Hicsonmez,A.; Ozkan,S..
The effect of ionizing irradiation on testes and the protective effects of melatonin were investigated by immunohistochemical and electron microscopic methods. Eighty-two adult male Wistar rats were divided into 10 groups. The rats in the irradiated groups were exposed to a sublethal irradiation dose of 8 Gy, either to the total body or abdominopelvic region using a 60Co source at a focus of 80 cm away from the skin in the morning or evening together with vehicle (20% ethanol) or melatonin administered 24 h before (10 mg/kg), immediately before (20 mg/kg) and 24 h after irradiation (10 mg/kg), all ip. Caspace-3 immunoreactivity was increased in the irradiated group compared to control (P < 0.05). Melatonin-treated groups showed less apoptosis as...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Testes; Gamma-irradiation; Melatonin; Immunohistochemistry; Electron microscopy.
Ano: 2009 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009000700006
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