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Registros recuperados: 37 | |
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Eiras-Stofella,Daura Regina; Gremski,Waldemiro; Kuligowski,Sandra Maria. |
The structure of the spermatozoon of Mugil curema Valenciennes, 1836 was studied using scanning and transmission electron microscopy. The spermatic head is rounded and formed by the nucleus containing granular chromatin, firmly packed resulting in a mass extremely electron dense. The acrossome is absent. The midpiece is characterized by the presence of two centrioles, a plasmatic canal, very few vesicles, and several mitochondria (9-10) with aproximately 0.50µm in diameter. The head and the midpiece are aproximately 1.56µm in diameter. The flagellum conforms to the 9 + 0 flagellar pattern near the transition region in its midpiece and is 9 + 2 from there on up to the distal region of the axoneme. The electron density in the A tubules 1, 2, 5 and 6 shows... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Teleostei; Mugilidae; Mullet; Mugil curema; Ultrastructure; Spermatozoa. |
Ano: 1993 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751993000400007 |
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Rosa,lerecê L; Rosa,Ricardo S. |
Five genera of marine fishes are recognized in the family Pinguipedidae: Pinguipes, Prolatilus, Pseudopercis, Paraperci and Kochichlhys, the first three being endemic to South America. The following South American pinguipedid species are considered valid: Pinguipes brasilianus, Pinguipes chilensis, Prolatilus jugularis, Pseudopercis numida, Pseudopercis semifasciata and Parapercis dockinski. Lecto-types are designated for Pinguipes brasilianus, Pinguipes chilensis and Prolatilus jugularis. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Teleostei; Pinguipedidae; South America; Revision. |
Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751997000400009 |
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Garcia,José Antônio Dias; Chini,Helena A.S.; Maistro,Edson Luis; Quagio-Grassiotto,Irani. |
Oogenesis involves a set of transformations which are undergone by female germ cells These cells change into oogonias and then into mature oocytes. Sexually mature female fish were collected monthly, during one year, from the Sapucaí River, a tributary of the Rio Grande, which is part of the Furnas Reservoir in the state of Minas Gerais. During the several stages of maturation, we observed small round oogonias with a large nucleus, a single nucleolus, and weakly stained cytoplasm with eosinophilic granules. The primary oocytes showed a large basophilic nucleus, with a developed peripheral nucleolus and a reduced cytoplasm. The previtellogenic oocytes presented voluminous cytoplasm and nucleus with several small peripheral nucleoli. The oocytes underwent... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Teleostei; Characidae; Astyanax fasciatus; Oogenesis; Cytochemical. |
Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752001000400003 |
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Chini,Helena A.S.; Garcia,José Antônio Dias; Maistro,Edson Luis; Quagio-Grassiotto,Irani. |
Oogenesis involves a sequense of transformations which are undergone by female germ cells. These cells change into oogonias and then into mature oocytes. Sexually mature females were collected monthly, during one year, from the Rio Sapucaí, tributary of the Rio Grande, which is part of the Furnas Reservoir system in the state of Minas Gerais. The observed material showed that oogonias were small spherical cells, had a big spherical nucleus, with a single nucleolus, and weakly stained cytoplasm with eosinophilic granules (FG stained), which indicate their protein content. The primary oocytes showed a big basophilic nucleus, with a large peripheral nucleolus, and several smaller nucleoli. They show a reduced cytoplasmic content. The previtellogenic oocytes... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Teleostei; Anostomidae; Leporinus striatus; Oogenesis; Cytochemical. |
Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752001000400004 |
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Oliveira Ribeiro,Ciro Alberto de; Fanta,Edith. |
The digestive system of Trichomycterus brasiliensis (Lütken, 1874), a small sized tropical Teleostean fish widely distributed in South America, was studied. Tissue samples were prepared for light and scanning electron microscopy (SEM). Trichomycterus brasiliensis shows stratified esophagus epithelium with taste buds and goblet cells with neutral and acid mucus at the anterior region. The stomach is caecal, presenting a pyloric valve with neutral mucus cells. At the terminal portion it is surrounded by a thick muscular wall. The intestine shows two loops; the epithelium is single columnar, with acid and neutral mucus in goblet cells. Multicellular intestinal glands are absent. Granular cells are often seen in the mucosa, less in the submucosa but were not... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Teleostei; Digestive tube; Histology. |
Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752000000400007 |
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Matos,Edilson; Matos,Patricia; Corral,Laura; Azevedo,Carlos. |
Spermatozoa of amazon fish, Acestrorhynchus falcatus Bloch, 1794 were investigated by optical microscopy (DIC) and electron microscopy (TEM). Spermatozoa have no acrosome, the head is ovoid, and the midpiece region cylindrical, contains spherical mitochondria. The centriolar complex is located at the lateral side of the nucleus, formed by nine peripheral pairs of microtubules and arranged in a right angle to each other. The flagellum consists of nine pairs of peripheral and two central microtubules. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Teleostei; Characidae; Acestrorhynchus falcatus; Ultrastructure; Spermatozoon. |
Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752000000300019 |
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Chaves,Paulo de Tarso C; Vendel,Ana Lúcia. |
The species of Citharichthys Bleeker, 1862, C. arenaceus Evermann & Marsh, 1900 and C. spilopterus Günther, 1862, are the most common flatfishes found in Guaratuba Bay, south Brazil. Different size categories of these flatfish occur in the mangrove area throughout the year. The Gonadosomatic Index, the Condition Factor, and the morphological analyses of the gonads from samples obtained between 1994 and 1996 reveals a spawning activity during late Spring and early Summer. This period coincides with the increase in temperature and decrease in salinity. Spawning evidence and the presence of ali size categories throughout the year indicate that Citharichthys spp. are permanent inhabitants of the mangrove in Guaratuba Bay, where they complete their life... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Teleostei; Pleuronectiformes; Fish reproduction; Guaratuba Bay; Brazil. |
Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751997000100007 |
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JIMÉNEZ-PRADO,Pedro; VASQUEZ,Fernando. |
RESUMEN La interpretación de la diversidad biológica puede resultar muy compleja, ya que existe una dinámica basada en el origen y en la diversificación de las especies, así como en los efectos antrópicos, tales como la introducción de especies invasoras, cuya consecuencia puede conducir a la extinción local de especies nativas. El objetivo de este trabajo fue analizar la variación temporal (2012 y 2017), tanto en composición como en distribución de la ictiofauna a lo largo del río Atacames, noroccidente del Ecuador. En 2012 se registró: 1) la presencia de Astyanax ruberrimus que se extinguió localmente para el 2017; y 2) la presencia de la tilapia (Orechromis niloticus) como única especie introducida a la que se sumó el guppy (Poecilia gillii) para el... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biodiversidad; Ecología acuática; Neotrópico; Teleostei. |
Ano: 2021 |
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-548X2021000100081 |
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Registros recuperados: 37 | |
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