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Registros recuperados: 82
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Estudo comparado do desenvolvimento de dois morfotipos larvais de Cochliomyia macellaria (Fabricius) (Diptera, Calliphoridae) Zoologia
Cunha-e-Silva,Sandra L.; Milward-de-Azevedo,Eliane M.V..
The possible dissimilitudes relating to the duration of the egg incubation period and larval stage of Cochliomyia macellaria (Fab., 1775) from offsprings of females from larvae with and without pigmentation on Malpighi tubules, morphotype 1 and 2, respectively, was questioned. The experiment was conducted in climatized chamber regulated at 30ºC, 65±10% RH and 14 hour photophase. No significant difference was observed on average duration of first and second larval instars berween the two morphotypes, taking into account not only the conventional interpretation for the reading of different development phases of the larval stages (morphotype 1:11.0 and 11.9 hours and morphotype 2:11.7 and 12.7 hours for first and second instars, respectively), but also the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Secondary screwworm; Blow fly; Ontogeny; Carrion-eating dipterous; Necrophagous flies.
Ano: 1992 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751992000200003
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Desenvolvimento inicial de larvas de Rhaphiodon vulpinus Agassiz (Characiformes, Cynodontidae) Zoologia
Sousa,Wilson Treger Zydowicz de; Severi,William.
The cynodontid fish Rhaphiodon vulpinus Agassiz, 1829, known as "peixe-cachorro", is the only species of the family oceurring in the Pantanal of Mato Grosso. The initial development of its larvae was characterized, based on material collected with a 500 µm mesh size plankton-net, in several biotopes of the Pantanal of Barão de Melgaço, State of Mato Grosso, Central Brazil. The analysis was carried out with 72 larvae with standard length (SL) between 4.7 and 13.8 mm. The morphometric measurements varied positively with standard length, and body proportions ranged 8.1-17.8% for head length (HL), 6.2-10.1% for body height, and 63.673.5%, 16.8-21.6%, and 61.8-78.2% SL, respectively for pre-dorsal, pre-pectoral and pre-anal distances. The eye diameter varied...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cynodontidae; Rhaphiodon vulpinus; Larval development; Ontogeny; Morphometrics.
Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752002000100006
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Técnicas de criação e alguns aspectos da biologia de Chrysomya albiceps (Wiedemann) (Diptera, Calliphoridae), em condiçoes de laboraterio Zoologia
Queiroz,Margareth M. de Carvalho; Milward-de-Azevedo,Eliane M.V..
The colony of C. albiceps (Wiedemann, 1819) was established from larvae and adults colected in the "Estação para Pesquisa Parasitológica W.O. Neitz" area at UFRRJ and Seropedica District, Itaguai, Rio de Janeiro. (Latitude: 22º45'S; Longitude: 43º41'W and Altitude: 33 metres). The biological aspects of this species were studied in climatized chambers regulated at 60±10% RH and 14 hours photophase. The duration and the viability of the larval and pupal stages of C. albiceps was 5,2 and 4,53 days; 95,75% and 94%, respectively. An effect of group was observed on the larvae at the first and second instar. The average weight of mature larvae was around 75 mg, varying between 12,2 to 120 mg. Only mature larvae with average weight higher than 42 mg have...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Blowfly; Ontogeny; Life cycle; Rearings methods.
Ano: 1991 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751991000100006
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Leaf glands of Banisteriopsis muricata (Malpighiaceae): distribution, secretion composition, anatomy and relationship to visitors Acta Botanica
Nery,Lays Araújo; Vieira,Milene Faria; Ventrella,Marília Contin.
ABSTRACT Leaf glands are common structures in Malpighiaceae and exhibit great morphological diversity, yet information on their anatomy, secretion and type of visitors remains scarce. The aim of this study was to describe the distribution, anatomical development and chemical and functional properties of leaf glands of Banisteriopsis muricata (Malpighiaceae). Leaves at different stages of development were collected and processed according to standard techniques for light and scanning electron microscopy. Secretion composition was determined by histochemical tests and test-strips, while gland funciton was determined by field observation of interactions with visitors. Leaf glands were located on the petiole and on the abaxial base of the leaf blade. The gland...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Anatomy; Ants; Extrafloral nectaries (EFNs); Histochemistry; Leaf glands; Nectar; Ontogeny.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062017000300459
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What are tilosomes? An update and new perspectives Acta Botanica
Kedrovski,Halisson Rafael; Sajo,Maria das Graças.
ABSTRACT Characterization of tilosomes and study of their development revealed that they are similar to the cell wall ingrowths of transfer cells. Roots from Anathallis sclerophylla were used to examine the development, histochemistry and ultrastructure of tilosomes using light, confocal and electron microscopy (both SEM and TEM). Tilosomes initiate as cellulosic papillae in the root elongation zone, increasing the apo/symplast surface throughout the wall-membrane apparatus. Both the development and structure of tilosomes and velamen strips appear similar to the reticulated and flange cell wall ingrowths of Vicia faba transfer cells. We suggest two functional phases for tilosomes: a) in young tissues they increase the symplast connection and thus improve...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Autofluorescence; Callose; Cell wall biochemistry; Ontogeny; Oriented wall deposition; Waxes.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062019000100106
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Structure and development of fruits and seeds of weed species of Euphorbiaceae Acta Botanica
Gagliardi,Karina Bertechine; Rosado,Aline; Souza,Luiz Antonio de; Moscheta,Ismar Sebastião; Albiero,Adriana Lenita Meyer.
Euphorbiaceae s.l. presents several morphological types of fruits, of which the schizocarp is the most common. The fruits of weed species of Euphorbia graminea Jacq., Euphorbia heterophylla L., Euphorbia hirta L. (= Chamaesyce hirta (L.) Millsp.) and Euphorbia prostrata Aiton (= Chamaesyce prostrata (Aiton) Small) are objects of this study. Inflorescences and fruits in development were collected on the campus of the State University of Maringa (UEM), Brazil, fixed in FAA 50 and glutaraldehyde, dehydrated and sectioned with a rotary microtome according to standard morphology and anatomy techniques. The species present several anatomical similarities, though there are some differences related to the outer epidermis of the ovaries, which is glabrous in E....
Tipo: Info:eu-repo/semantics/article Palavras-chave: Euphorbia; Ontogeny; Pericarp; Schizocarp; Seedcoat.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062012000100005
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Corona development and floral nectaries of Asclepiadeae (Asclepiadoideae, Apocynaceae) Acta Botanica
Monteiro,Mariana Maciel; Demarco,Diego.
ABSTRACT Flowers of Asclepiadoideae are notable for possessing numerous nectaries and elaborate coronas, where nectar can accumulate but is not necessarily produced. Given the complexity and importance of these structures for reproduction, this study aimed to analyze the ontogeny of the corona, the structure and position of nectaries and the histochemistry of the nectar of species of Asclepiadeae. Two types of coronas were observed: androecial [C(is)] and corolline (Ca). The development of the C(is)-type of corona initiates opposite the stamens in all species examined with the exception of Matelea in which it begins to develop as a ring around the filament tube. Despite their morphological variation, coronas typically originate from the androecium. A...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Asclepiads; Histochemistry; Ontogeny; Nectar; Structural; Diversity.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062017000300420
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Embryology of Ageratum conyzoides L. and A. fastigiatum R.M. King & H. Rob. (Asteraceae) Acta Botanica
Franca,Rafael de Oliveira; De-Paula,Orlando Cavalari; Carmo-Oliveira,Renata; Marzinek,Juliana.
Ageratum has a complex circumscription, and recent studies have indicated its polyphyletism. The genus has been placed in the tribe Eupatorieae whose embryology is not fully known. Embryological data are conservative and important indicators of phylogenetic relationships and can improve family relationships. This study presents, for the first time in Eupatorieae, embryological data for Ageratum conyzoides and A. fastigiatum. Both species have common features of the family such as a unitegmic anatropous ovule, basal placentation, secretory tapetum, Polygonum megagametophyte, and Asterad embryogenesis. The data obtained reinforce the heterogeneity of the family embryology and show, for the first time, the anther wall development of the monocotyledonous type...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Compositae; Embryogenesis; Eupatorieae; Ontogeny; Phytomelanin.
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062015000100008
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Pericarp structure in Banisteriopsis C.B.Rob. and Diplopterys A.Juss. (Malpighiaceae): new data supporting generic segregation Acta Botanica
Souto,Letícia Silva; Oliveira,Denise Maria Trombert.
Molecular studies have indicated that some species of Banisteriopsis would be more appropriately placed in Diplopterys. Both of these genera are neotropical members of the Malpighiaceae, a family that is widely diverse in South America, especially in the Brazilian savanna (cerrado). Studies concerning the anatomy of the reproductive organs of Malpighiaceae from the cerrado are very rare. Thus, the present work describes the morphology, anatomy, and ontogeny of the pericarp of B. campestris, B. oxyclada, B. stellaris, and D. pubipetala, comparing them and identifying characteristics that could support the segregation of genera. The fruits of Banisteriopsis studied here demonstrate structures very similar among themselves, while D. pubipetala shows numerous...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Banisteriopsis campestris; Banisteriopsis oxyclada; Banisteriopsis stellaris; Diplopterys pubipetala; Ontogeny.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062012000300003
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Ontogeny, structure and moulting of Parabolina frequens argentina (Kayser) (Trilobita, Olenidae) from the Furongian of northwestern Argentina Ameghiniana
Tortello,M. Franco; Clarkson,Euan N.K..
Parabolina frequens argentina (Kayser) (Trilobita, Olenidae) is a guide fossil occurring in different assemblages and lithologies of the upper Cambrian (Furongian) of northwestern Argentina. The black and dark grey shales of the Lampazar Formation at sierra de Cajas and the Santa Rosita Formation (lower part) at Iruya and Alfarcito (Jujuy and Salta provinces) contain numerous well-preserved specimens at different stages of development. The juveniles represent anaprotaspis, metaprotaspis and degrees 0-11 meraspis. The latter exhibit a high variability related with the pattern of glabellar furrows and lobes, the sagittal length of the thoracic segments, the splay and length of the genal and thoracic spines, the relative width of the axis, and the relative...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Parabolina; Trilobita; Olenidae; Furongian; Argentina; Ontogeny; Morphology; Ecdysis.
Ano: 2008 URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0002-70142008000100002
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Comments on Triassic pterosaurs with discussion about ontogeny and description of new taxa Anais da ABC (AABC)
Kellner,Alexander W.A..
Eudimorphodon ranzii was the first Triassic pterosaur to be described and several specimens have been referred to this taxon mainly based on the presence of multicuspid teeth. Since this dental feature has been observed in several other pterosaurs, the revision of some specimens assigned to Eudimorphodon shows that they represent new taxa as follows: Arcticodactyluscromptonellus (comb. nov.), Austriadraco dallavecchiai (gen. et sp. nov.) and Bergamodactyluswildi (gen. et sp. nov.). A preliminary analysis of pterosaur ontogeny resulted in the recognition of six distinct ontogenetic stages (OS1-6). According to this classification, the holotype of Arcticodactyluscromptonellus has reached OS2, and although being ontogenetically much younger than others, the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Pterosauria; Ontogeny; Eudimorphodon; Arcticodactylus; Austriadraco; Bergamodactylus.
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000200669
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Trichomes and chemical composition of the volatile oil of Trichogonia cinerea (Gardner) R. M. King & H. Rob. (Eupatorieae, Asteraceae) Anais da ABC (AABC)
FERNANDES,YANNE S.; TRINDADE,LUMA M.P.; REZENDE,MARIA HELENA; PAULA,JOSÉ R.; GONÇALVES,LETÍCIA A..
Trichogonia cinerea is endemic to Brazil and occurs in areas of cerrado and campo rupestre. In this study, we characterized the glandular and non-glandular trichomes on the aerial parts of this species, determined the principal events in the development of the former, and identified the main constituents of the volatile oil produced in its aerial organs. Fully expanded leaves, internodes, florets, involucral bracts, and stem apices were used for the characterization of trichomes. Leaves, internodes, florets, and involucral bracts were examined by light microscopy and scanning electron microscopy, whereas stem apices were examined only by light microscopy. Branches in the reproductive phase were used for the extraction and determination of the composition...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Volatile oil; Histochemistry; Ontogeny; Secretory structure.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652016000100309
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Ontogenic development of kidney, thymus and spleen and phenotypic expression of CD3 and CD4 receptors on the lymphocytes of cobia (Rachycentroncanadum ) Anais da ABC (AABC)
KLOSTERHOFF,MARTA C.; PEREIRA JÚNIOR,JOABER; RODRIGUES,RICARDO V.; GUSMÃO,EMELINE P.; SAMPAIO,LUÍS A.; TESSER,MARCELO B.; ROMANO,LUIS A..
ABSTRACT In the present study was evaluated the ontogenic of immunocompetent organs of cobia up to 53 days after hatching (dah) through histology and immunohistochemistry techniques. The kidney was the first lymphohematopoietic organ to appear, at 1 dah, followed by the spleen at 5 dah and the thymus at 7 dah. The first CD3 receptors on the lymphocytes were observed in 27% of the thymic tissue at 7 dah and in 99% at 53 dah. The phenotypic expression of CD3 receptors was registered in 10% of the kidney at 8 dah and in 32% at 53 dah. CD4 receptors were observed in 5% and 63% of the thymic area at 7 and 53 dah, respectively. In the kidney, T4 lymphocytes were first observed at 13 dah in 9% of the organ and in 28% at 53 dah, defining the functional development...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cobia; Immune system; Ontogeny; Immunohistochemistry; Lymphoid organs.
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000502111
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New Material of Sinopterus (Pterosauria, Tapejaridae) from the Early Cretaceous Jehol Biota of China Anais da ABC (AABC)
ZHANG,XINJUN; JIANG,SHUNXING; CHENG,XIN; WANG,XIAOLIN.
Abstract: Tapejaridae is a clade of toothless pterosaurs typically characterized by a large nasoantorbital fenestra and a premaxillary crest that extends from the anterior to the posterior part of the skull. Sinopterus dongi was the first reported Chinese tapejarid. Another genus “Huaxiapterus” was described, but it was later on determined that “Huaxiapterus” is in fact an invalid name. Here, we report on a new juvenile specimen of Sinopterus atavismus from the Jiufotang Formation of western Liaoning, China, and revise the diagnosis of this species. Sinopterus atavismus does not present a square-like crest. Moreover the feature that groove in the ventral part of the second or third phalanx of manual digit IV is not diagnostic of the species. In the new...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Sinopterus atavismus; Ontogeny; Jiufotang Formation; Liaoning; China.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000400513
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Are the dinosauromorph femora from the Upper Triassic of Hayden Quarry (New Mexico) three stages in a growth series of a single taxon? Anais da ABC (AABC)
MÜLLER,RODRIGO T..
ABSTRACT The lagerpetid Dromomeron romeri and the theropod Tawa hallae are two dinosauromorphs from the Norian (Upper Triassic) of the Chinle Formation, situated in New Mexico, USA. However, a recent study suggests the inclusion of the holotype of D. romeri (GR 218) and paratype (GR 155) and referred (GR 235) specimens of T. hallae in an ontogenetic series of a single species. The specimens GR 218 and GR 155 include just an isolated femur, while GR235 includes femora, pelvis and tail. The inclusion of the specimens in an unique ontogenetic series relies on the putative immature condition and plastic deformation of the specimen GR 218. However, as observed here, the disparity between the femora of D. romeri and T. hallae is considerably higher than those...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Chinle Formation; Dinosauria; Dinosauriformes; Lagerpetidae; Norian; Ontogeny.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000300835
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Ubisch bodies and pollen ontogeny in Oxalis articulata Savigny Biocell
Rosenfeldt,Sonia; Galati,Beatriz G..
The correlation between the ontogeny of Ubisch bodies and pollen development in Oxalis articulata was studied with Transmission Electron Microscopy (TEM). The ultrastructural changes observed during the different stages of development in the tapetal cells are related to Ubisch bodies, sporopollenin and pollen-kitt formation. The pro-orbicules have the appearance of lipid globuli and their formation is related to the endoplasmic reticulum of rough type (ERr). The lipid globules or pro-orbicules disappear in the mature Ubisch bodies, and the places that they occupied remain free of contents or with pollen-kitt.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Pollen; Ubisch bodies; Ontogeny; Utrastructure; Oxalis.
Ano: 2005 URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452005000300004
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Ontogenetic changes in the fractal geometry of the bronchial tree in Rattus norvegicus Biol. Res.
CANALS,MAURICIO; OLIVARES,RICARDO; LABRA,FABIAN; NOVOA,FRANCISCO F.
Respiration and metabolism change dramatically over the course of the development of vertebrates. In mammals these changes may be ascribed to organogenesis and differentiation of structures involved in gas exchange and transport and the increase in size. Since young as well as mature individuals must be well-designed if the species is to survive, the physiological changes during the development should be matched with geometrical or structural adjustments of the respiratory system. The aim of this study was to evaluate changes in the fractal geometry of the bronchial tree during the postnatal development of the rat. The average fractal dimension of the bronchial tree of the rats was 1.587, but that of juveniles was larger than that of the adults. We found...
Tipo: Journal article Palavras-chave: Bronchial tree; Fractals; Ontogeny.
Ano: 2000 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602000000100010
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Symmorphosis in the proximal pathway for oxygen in the leaf-eared mouse Phyllotis darwini Biol. Res.
CANALS,MAURICIO; FIGUEROA,DANIELA; SABAT,PABLO.
In this report, we explore the matching of structures to functional needs by comparing previously reported data of maximal oxygen consumption and the development of the lung in the leaf-eared mouse Phyllotis darwini in warm and cold environments. We discuss whether the state of structural design is commensurate with functional needs from regulated morphogenesis as predicted by the hypothesis of symmorphosis. We found a close match between respiratory structures and functional needs during postnatal development, expressed as safety factors close to unity. However, in the adult stage the safety factors were greater than two, which suggests that adult animals acquired a structure greater than that required considering their maximum capacities. A high safety...
Tipo: Journal article Palavras-chave: Metabolism; Ontogeny; Phyllotis darwini; Symmorphosis.
Ano: 2010 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602010000100009
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Somatic embryogenesis from immature cotyledons of soybean (Glycine max (L.) Merr.): ontogeny of somatic embryos BABT
Santos,Karla Galvão Bezerra dos; Mariath,Jorge Ernesto de Araújo; Moço,Maria Cecília C.; Bodanese-Zanettini,Maria Helena.
Soybean somatic embryos obtained from immature zygotic embryos were histologically analyzed in order to determine possible ontogenetic routes followed by these embryos. The proembryo stage and globular, heart-shaped, torpedo and cotyledonary embryo stages were found, closely resembling the ontogeny of zygotic embryos. However, the absence of a characteristic suspensor as well as the delay in the establishment of inner organization were the main differences between these two embryogenic processes.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Glycine max; Ontogeny; Somatic embryo.
Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000100006
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Ontogenetic patterns and genetic variation in Anopheles (Anopheles) intermedius Chagas, 1908 and Anopheles (Anopheles) mattogrossensis Lutz & Neiva, 1911 (Diptera: Culicidae) in the Brazilian Amazon BJB
RODRIGUEZ,G. A. D.; SANTOS,J. M. M. dos; MAIA,J. de F..
Changes in the expression of genes were observed during development in populations of Anopheles (Anopheles) intermedius and Anopheles (Anopheles) mattogrossensis. Esterase showed seven zones of activity: EST1 was present in all developmental stages of both species; EST2 was observed only in larvae of A. intermedius and larvae and pupae of A. mattogrossensis, with greater activity in pupae; EST3 and EST5 were present in all developmental stages, with greater intensity in larvae; EST4 and EST6 showed weak activity in larvae of A. mattogrossensis and was not found in A. intermedius. Leucine aminopeptidase showed four zones of activity, of which LAP1 and LAP2 were found in all stages of A. intermedius, with highest activity in larvae, and in larvae only of A....
Tipo: Info:eu-repo/semantics/article Palavras-chave: Anopheles intermedius; Anopheles mattogrossensis; Ontogeny; Isozymes; Malaria.
Ano: 2000 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0034-71082000000200020
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