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| Registros recuperados: 94 | |
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| Baeza,Carlos; Ruiz,Eduardo; Negritto,María. |
| Alstroemeria L. (Alstroemeriaceae) is an American genus of monocots with two principal distribution centers in Chile and Brazil. In Chile, it is represented by about 32 species, most of them in central Chile, an area known for its high level of endemism. The "complex" Alstroemeria hookeri is endemic to Chile, where it is distributed from the Coquimbo to the Bío-Bío Region. We analyzed the karyotypes of 36 populations of this complex along its natural distribution. Ten metaphases per population were used for chromosome measurements. All analyzed subspecies presented a well defined asymmetric karyotype. The populations of A. hookeri subsp. hookeri collected in the coastal range of the Bío-Bío Region and the populations from the Central Valley of this Region... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Alstroemeria hookeri; Complex; Karyotype; Polymorphisms; Chile. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000100020 |
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| Silva,Guilherme Messias da; Bione,Edgar Guimarães; Cabral-de-Mello,Diogo Cavalcanti; Moura,Rita de Cássia de; Simões,Zilá Luz Paulino; Souza,Maria José de. |
| Meiotic and mitotic chromosomes of Dichotomius nisus, D. semisquamosus and D. sericeus were analyzed after conventional staining, C-banding and silver nitrate staining. In addition, Dichotomius nisus and D. semisquamosus chromosomes were also analyzed after fluorescent in situ hybridization (FISH) with an rDNA probe. The species analyzed had an asymmetrical karyotype with 2n = 18 and meta-submetacentric chromosomes. The sex determination mechanism was of the Xy p type in D. nisus and D. semisquamosus and of the Xyr type in D. sericeus. C-banding revealed the presence of pericentromeric blocks of constitutive heterochromatin (CH) in all the chromosomes of the three species. After silver staining, the nucleolar organizer regions (NORs) were located in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome rearrangements; Heterochromatin; Karyotype; NORs; FISH. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000200012 |
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| Dantas,Liliane G.; Guerra,Marcelo. |
| A comparative analysis of mitotic chromosomes of Theobroma cacao (cacao) and T. grandiflorum (cupuaçu) was performed aiming to identify cytological differences between the two most important species of this genus. Both species have symmetric karyotypes, with 2n = 20 metacentric chromosomes ranging in size from 2.00 to 1.19 µm (cacao) and from 2.21 to 1.15 mm (cupuaçu). The interphase nuclei of both species were of the arreticulate type, displaying up to 20 chromocentres, which were more regularly shaped in cacao than in cupuaçu. Prophase chromosomes of both species were more condensed in the proximal region, sometimes including the whole short arm. Both species exhibited only one pair of terminal heterochromatic bands, positively stained with chromomycin... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cacao; Cupuaçu; Heterochromatin; Karyotype; RDNA sites; Theobroma. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000100017 |
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| Nogueira,Denise M.; Ferreira,Ana Maria R.; Goldschmidt,Beatriz; Pissinatti,Alcides; Carelli,Juliane B.; Verona,Carlos E.. |
| In the Atlantic forest of Rio de Janeiro, Callithrix aurita (É. Geoffroy in Humboldt, 1812) is a native species vulnerable to extinction and C. jacchus (Linnaeus, 1758) and C. penicillata (É. Geoffroy, 1812) are invasive species. The major threats to the native species are habitat degradation and hybridization, although there are currently no genetic data about natural hybrids available. Previous studies have revealed that species of the Callithrix genus are extremely homogeneous in their karyotypes with the exceptions of the morphology and size of the Y chromosome and its nucleolar organizer region (NOR) banding pattern. Three male marmosets captured in the wild in Guapimirim municipality, Rio de Janeiro, Brazil, considered as possible hybrids between C.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Marmosets; Y-chromosome; Karyotype; Hybridization. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212011000200002 |
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| Lima,J. Fernando de S.; Kasahara,Sanae. |
| The genus Calomys Waterhouse, 1837 is widely distributed within South America, being found in Venezuela, Colombia, Peru, Bolivia, Brazil, Paraguay, Uruguay and Argentina. Specimens of Calomys were collected in Formoso do Araguaia, Tocantins, Brazil. For chromosome characterization standard staining techniques and as G-banding and nucleolar organizer region were used. The karyotype was 2n=46 and AN=66. The X chromosome is a medium metacentric and the Y chromosome a small acrocentric chromosome. Chromosome homologies with other species were observed. Probably, karyotype differences were basically due to Robertsonian rearrangements. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Calomys; Karyotype; Chromosome; Tocantins; Brazil. |
| Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212001000200019 |
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| Leitao, Alexandra; Boudry, Pierre; Labat, Jean-philippe; Thiriot-quievreux, Catherine. |
| Chromosomes of six cupped oyster species were studied using karyometric analysis alter conventional Giemsa staining, and silver staining, Karyotypes of Crassotrea angulata (nine metacentric and one submetacentric chromosome pairs), C. sikamea (nine metacentric and one submetacentric chromosome pairs), C. virginica (eight metacentric and two submetacentric chromosome pairs), C, ariakensis (eight metacentric and two submetacentric chromosome pairs), C, gasar (six metacentric and four submetacentric chromosome pairs), and Saccostrea commercialis (eight metacentric and two submetacentric chromosome pairs) are distinguishable by the number and position of the submetacentric chromosome pair and by the location of nucleolus organizer regions, Comparative... |
| Tipo: Text |
Palavras-chave: Bivalvia; Cytotaxonomy; Karyotype; Chromosome; Cupped oyster. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/1999/publication-2737.pdf |
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| Leitao, Alexandra; Boudry, Pierre; Thiriot Quievreux, Catherine. |
| The G-banding technique was performed on aneuploid karyotypes from gill tissue of the Pacific oyster, Crassostrea gigas, to assess whether chromosome losses could be explained by differential chromosomal susceptibility and to clarify the negative correlation between aneuploidy and growth rate previously reported in different populations of this oyster. The study of 95 G-banded aneuploid karyotypes showed that only 4 of the 10 chromosome pairs (viz. 1, 5, 9, and 10) of C. gigas were affected by the loss of one homologous chromosome. Pairs 1, 9, and 10, which were lost in 56, 33, and 44% of cases, respectively, may be considered to be differentially affected. Hypotheses on this differential chromosomal susceptibility are discussed. |
| Tipo: Text |
Palavras-chave: Oyster; Karyotype; G banding; Growth; Aneuploidy; Huître; Caryotype; Bandes G; Croissance; Aneuploïdie. |
| Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/publication-742.pdf |
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| Lapegue, Sylvie; Boutet, Isabelle; Leitao, Alexandra; Heurtebise, Serge; Garcia, P; Thiriot Quievreux, C; Boudry, Pierre. |
| Three species of man.-rove oysters, Crassostrea rhizophorae, C. brasiliana, and C. gasar, have been described along the Atlantic shores of South America and Africa. Because the distribution of these molluscs is of great biological and commercial interest, their taxonomy and distribution deserve further clarification. Therefore, 15 populations were sampled from both continents. Their 16S mitochondrial polymorphism was studied by sequencing and PCR-RFLP analysis. Two haplotypes were identified. Haplotype a was the only one observed in Africa, but it was also observed in South America together with haplotype b. Because C. gasar is the only mangrove oyster identified on the west coast of Africa, haplotype a was attributed to this species, which has thus been... |
| Tipo: Text |
Palavras-chave: Mangrove oyster; Crassostrea gasar; Karyotype; Phylogeography; 16S mitochondrial DNA. |
| Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/2002/publication-2790.pdf |
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| Matias, A. M.; Diaz, S.; Teixeira De Sousa, Joana; Villalba, A.; Carballal, M. J.; Leitao, A.. |
| Disseminated neoplasia (DN) is characterized by an abnormal cell proliferation, usually resulting in death of the affected mollusks. In the present study we performed, for the first time, karyotypes of two different stages of DN in the cockle Cerastoderma edule. Analysis of moderate (N2) and high (N3) severity neoplasic metaphases displayed a chromosome number ranging from 57 to 317, instead of the normal diploid number of 38. Cockles with N2 showed a lower percentage of microchromosomes and a higher ploidy than those with N3. The comparison of both cytogenetic profiles contributes to better understand the evolution of DN in cockles. |
| Tipo: Text |
Palavras-chave: Karyotype; Disseminated neoplasia; Cerastoderma edule; Microchromosomes. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00184/29550/27876.pdf |
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| Jara-Seguel,Pedro; Urrutia-Estrada,Jonathan. |
| Chilean Plants Cytogenetic Database (CPCD) is a resource available on line in electronic format, which provides a cytogenetics catalogue for continental and insular Chilean vascular plants. In this report, we made reference to the CPCD, discussing aspects on its coverage, features and usages. Currently, the database stores cytogenetic information for 247 species, 107 genera, and 55 families belonging to Pteridophyta, Pinophyta, and Magnoliophyta. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome number; Karyotype; Chilean Plants. |
| Ano: 2018 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1852-62332018000100006 |
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| Ferreira,Amilton; Mesa,Alejo. |
| The thirteen species of Phaneropterinae here studied can be arranged in four different groups according to their basic karyological traits. All of them share the same kind of chromosomal sex determining mechanism with X0(male) and XX(female). The X chromosome differs among species and always appears heteropycnotic during prophase I, it is the largest in the set and segregates precociously during anaphase I. Among the species, the karyotypes varies in fundamental number between 31 to 21. The meaning of these significant changes in the karyotypes in relation to the phylogeny within some large taxonomic group of species is discussed. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotype; Chromosome; Evolution. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2007000400003 |
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| Nirchio,Mauro; Rondón,Rodolfo; Oliveira,Claudio; Ferreira,Irani A.; Martins,Cesar; Pérez,Julio; Sola,Luciana; Rossi,Anna Rita. |
| In the present study, three species of Lutjaninae, Lutjanus analis, L. griseus and L. synagris, were analyzed by conventional Giemsa staining, C-banding and silver staining, to reveal active Nucleolus Organizer Regions (NORs). Fluorescent in situ hybridization (FISH) was also applied to establish the number and location of the ribosomal gene clusters (18S and 5S rRNA genes). Counts of diploid metaphasic cells revealed a diploid modal chromosome complement composed of 48 acrocentric chromosomes in both L. analis and L. griseus. Two cytotypes were observed in L. synagris: cytotype I, with 2n=48 acrocentric chromosomes, found in 19 specimens, and cytotype II, with 46 acrocentric chromosomes and one large metacentric, found in two specimens. The large... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotype; Ribosomal genes; NOR polymorphism; C-banding; Robertsonian rearrangement. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000100012 |
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| Artoni,Roberto Ferreira; Shibatta,Oscar Akio; Gross,Maria Claudia; Schneider,Carlos Henrique; Almeida,Mara Cristina de; Vicari,Marcelo Ricardo; Bertollo,Luiz Antonio Carlos. |
| Four populations of Astyanax aff. fasciatus of the upper rio Tibagi (municipal district of Ponta Grossa, Paraná State, Brazil), had their karyotypes and morphometry analyzed. The cytogenetic data show the occurrence of distinct karyotypes (cytotypes), here named cytotype A, with 2n=48 chromosomes (6m+18sm+14st+10a), cytotype B, with 2n=50 chromosomes (8m+18sm+14st+10a) and cytotype C, with 2n=50 chromosomes (8m+18sm+14st+10a). The distribution pattern of the constitutive heterochromatin was very similar between cytotypes A and B, but diverged in relation to cytotype C. Distinct cytotypes may occur in sympatry in the upper rio Tibagi region, with the exception of the Furna 2 sample, which presents cytotype A exclusively. In addition, a specimen with 2n=49... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Tetra; Morphometrics; Karyotype; Sympatry; Cryptic species. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000200005 |
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| Teixeira,Thais K. S. S.; Venere,Paulo C.; Ferreira,Daniela C.; Mariotto,Sandra; Castro,Jonathan P.; Artoni,Roberto F.; Centofante,Liano. |
| ABSTRACT Astyanax is one of the most abundant and diverse taxa of fishes in the Neotropical region. In order to increase the amount of cytogenetic information for Astyanax as well as to exhibit data to subsidize future taxonomic studies, this work analyzed three species of Astyanax: two species are cryptic, and are here reported to live in syntopy (A. abramis and A. lacustris); the first karyotype description for A. pirapuan is also presented. Cytogenetic analyzes reveal a diploid number of 2n=50 chromosomes for three species, yet with differences in their karyotype morphology. The physical mapping of 18S rDNA showed up to thirteen sites in A. pirapuan and two in A. abramis and A. lacustris. The physical mapping of 5S rDNA has proven to be an effective... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cryptic species; Fish; Karyotype; Species complex. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252018000100214 |
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| Swarça,Ana Claudia; Orsi,Mário Luis; Takagui,Fábio Hiroshi; Dias,Ana Lucia; Dergam,Jorge Abdala; Fenocchio,Alberto Sérgio. |
| ABSTRACT The present report represents the first cytogenetic description of Steindachneridion doceanum, great catfish which is currently at high extinction risk and it is listed as threatened on the red list of the Brazilian Ministry of the Environment, also are suggested karyotype relationships with other species of the same genus endemic from other river basins. The results revealed a diploid number of 2n = 56 and the karyotype composed of 18 metacentric, 20 submetacentric, 10 subtelocentric and 8 acrocentric chromosomes (NF = 104). The AgNORs and CMA3 signals were coincident in location occupying the short arm of an acrocentric chromosome pair (25th), in a secondary constriction. The 5S rDNA genes were localized on the short arms of one subtelocentric... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: AgNORS; C band; Karyotype; South American Catfish; Threatened species. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252018000400203 |
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| Registros recuperados: 94 | |
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