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Registros recuperados: 404 | |
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Scholtz, Gerhard; Wolff, Carsten. |
Investigations of amphipod embryonic development have a long tradition. However, many aspects of amphipod embryology are still controversial. These concern, among others, the nature of the cleavage, the origin of the germ disc, and the mode of gastrulation. On the other hand, amphipods show the same characteristic type of invariant cell division pattern in the germ band as other malacostracans. Since amphipods seem to undergo a stereotyped pattern of early cleavage they are highly interesting for our understanding of the evolution of arthropod development. In this paper, we describe the cleavage pattern of the amphipod crustacean Orchestia cavimana from the zygote to gastrulation and the formation of the germ disc using direct observation, scanning... |
Tipo: Article / Letter to the editor |
Palavras-chave: Cell lineage; Cell migration; Arthropoda; Phylogeny; Evolution. |
Ano: 2002 |
URL: http://www.repository.naturalis.nl/record/534334 |
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Brisbarre, Nadège; Fardeau, Marie-laure; Cueff, Valerie; Cayol, Jean-luc; Barbier, Georges; Cilia, Valérie; Ravot, Gilles; Thomas, Pierre; Garcia, Jean-louis; Ollivier, Bernard. |
A strictly anaerobic, slightly halophilic and moderately thermophilic, sporulating rod designated strain DVird3(T) was isolated from deep-sea hydrothermal vent samples collected at a depth of approximately 800 m on the Atlantic Ocean Ridge. Strain DVird3(T) possessed a few laterally inserted flagella, had a DNA G+C content of 33.1 mol% and grew optimally at pH 6.6 and at 45 degreesC. Growth was observed at temperatures between 20 and 58 degreesC and at pH values between 5.8 and 8.2. The optimum NaCl concentration for growth was 3% sea salt (30 g l(-1)); no growth was observed in the presence of 15 or 60 g sea salt l(-1). Strain DVird3(T) is heterotrophic and utilizes some sugars and various single amino acids. Acetate was the main fatty acid detected from... |
Tipo: Text |
Palavras-chave: Phylogeny; Thermophile; Bacteria; Deep sea hydrothermal vent. |
Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/publication-588.pdf |
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Spadella,Maria A.; Oliveira,Claudio; Quagio-Grassiotto,Irani. |
In Corydoradinae, the presence of spermatids in the lumen of the testicular tubules together with spermatozoa suggests that spermatogenesis is of the semicystic type, whereas in Callichthyinae, sperm production occurs entirely within spermatocysts in the germinal epithelium, characterizing cystic spermatogenesis. Spermiogenesis in Callichthyinae is characterized by an initial lateral development of the flagellum, the presence of nuclear rotation to different degrees, an eccentric or medial formation of a nuclear fossa, formation of a cytoplasmic channel, and presence of centriolar migration, being more similar to type I spermiogenesis. In Corydoradinae, spermiogenesis is characterized by eccentric development of the flagellum, the absence of nuclear... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Catfish; Spermatid; Spermatozoa; Phylogeny; Morphology. |
Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252007000300014 |
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Quagio-Grassiotto,Irani; Spadella,Maria Angélica; Carvalho,Márcio de; Oliveira,Claudio. |
The data obtained in the present study on spermiogenesis and spermatozoal ultrastructure of Pseudopimelodidae and Heptapteridae show that they share some characteristics, but greatly differ from each other. The main differences are the occurrence of type I spermiogenesis in Pseudopimelodidae and type III in Heptapteridae, the presence of nuclear fossa in Pseudopimelodidae and its absence in Heptapteridae, the presence of long midpiece in Pseudopimelodidae and short midpiece in Heptapteridae, the presence of cytoplasmic canal in Pseudopimelodidae and its absence in Heptapteridae, the presence of many large vesicles in the midpiece of Pseudopimelodidae and the presence of very long vesicles placed in the peripheral distal region in Heptapteridae, and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Catfish; Spermatid; Sperm; Structure; Phylogeny. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252005000300008 |
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Soon-Jeong,Jeong; Joo-Cheol,Park; Heung-Joong,Kim; Chun,Sik Bae; Myung-Hee,Yoon; Do-Seon,Lim; Moon-Jin,Jeong. |
This study examined the fine structures of epididymal spermatozoa on the lesser white-toothed shrew ( Crocidura suaveolens ), the Japanese white-toothed shrew ( C. dsinezumi ) and the big white-toothed shrew ( C. lasiura ) belonging to the subfamily Crocidurinae living in Korea . In the spermatozoa of C. suaveolens , the head has a large acrosome, a smooth inner acrosomal membrane and a wavy, finger-like, electron-dense apical body. The neck has a solid proximal centriole that is filled with electron-dense material. These results showed the spermatozoa of C. suaveolens possess the characteristics of both Crocidurinae and Soricinae. In C. dsinezumi and C. lasiura , the head has a large acrosome, a serrated inner acrosomal membrane and a common apical body.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Crocidurinae; Shrew; Spermatozoa; Phylogeny; Fine structure. |
Ano: 2006 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-95452006000200003 |
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Goudenege, David; Labreuche, Yannick; Krin, Evelyne; Ansquer, Dominique; Mangenot, Sophie; Calteau, Alexandra; Medigue, Claudine; Mazel, Didier; Polz, Martin F.; Le Roux, Frederique. |
Vibrio nigripulchritudo is an emerging pathogen of farmed shrimp in New Caledonia and other regions in the Indo-Pacific. The molecular determinants of V. nigripulchritudo pathogenicity are unknown; however, molecular epidemiological studies have suggested that pathogenicity is linked to particular lineages. Here, we performed high-throughput sequencing-based comparative genome analysis of 16 V. nigripulchritudo strains to explore the genomic diversity and evolutionary history of pathogen-containing lineages and to identify pathogen-specific genetic elements. Our phylogenetic analysis revealed three pathogen-containing V. nigripulchritudo clades, including two clades previously identified from New Caledonia and one novel clade comprising putatively... |
Tipo: Text |
Palavras-chave: Horizontal gene transfer; Nigritoxin; Phylogeny; Shrimp; Virulence; Vibrio. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00160/27117/28369.pdf |
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Soares-Ramos,Juliana R.L.; Ramos,Humberto J.O.; Cruz,Leonardo M.; Chubatsu,Leda S.; Pedrosa,Fábio O.; Rigo,Liu U.; Souza,Emanuel M.. |
Herbaspirillum spp. are endophytic diazotrophic bacteria associated with important agricultural crops. In this work, we analyzed six strains of H. seropedicae (Z78, M2, ZA69, ZA95, Z152, and Z67) and one strain of H. rubrisubalbicans (M4) by restriction fragment length polymorphism (RFLP) using HindIII or DraI restriction endonucleases, random amplified polymorphic DNA (RAPD), and partial sequencing of 16S rDNA. The results of these analyses ascribed the strains studied to three distinct groups: group I, consisting of M2 and M4; group II, of ZA69; and group III, of ZA95, Z78, Z67, and Z152. RAPD fingerprinting showed a higher variability than the other methods, and each strain had a unique electrophoretic pattern with five of the six primers used.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Herbaspirillum; RAPD; RFLP; Phylogeny; 16S rDNA. |
Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000400019 |
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Simone,Luiz Ricardo L.. |
This study deals with detailed morphology and anatomy of 4 species of Scaphopoda and 5 species of protobranch Bivalvia. Both classes are traditionally grouped in the taxon Diasoma, which has been questioned by different methodologies, such as molecular and developmental. This study is developed under a phylogenetic methodology with the main concern in performing it in an intelligible and testable methodology. The analyzed Scaphopoda species came from the Brazilian coast and belong to the family Dentaliidae [(1) Coccodentalium carduus; (2) Paradentalium disparile] and Gadiliidae; [(3) Polyschides noronhensis, n. sp. from Fernando de Noronha Archipelago; (4) Gadila braziliensis]. These species represent the main branches of the class Scaphopoda. From... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Scaphopoda; Bivalvia; Diasoma; Phylogeny; Morphology. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0031-10492009003200001 |
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Rasnitsyn, Alexandr P.. |
Phylogenetic hypotheses are designed and tested (usually in implicit form) on the basis of a set of presumptions, that is, of statements describing a certain order of things in nature. These statements are to be accepted as such, no matter whatever evidence for them exists, but only in the absence of reasonably sound evidence pleading against them. A set of the most current phylogenetic presumptions is discussed, and a factual example of a practical realization of the approach is presented. A comparison is made of the three main taxonomic approaches hitherto developed, viz., phenetics, cladistics, and phylistics (= evolutionary systematics). The latter term denotes an approach that tries explicitly to represent the basic features of traditional taxonomy... |
Tipo: Article / Letter to the editor |
Palavras-chave: Phylogeny; Taxonomy; Phenetics; Cladistics; Phylistics; Principles of nomenclature; Type concept; Paleoentomology; Xyelidae (Vespida). |
Ano: 1996 |
URL: http://www.repository.naturalis.nl/record/504631 |
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Maas, P.J.M.; Westra, L.Y.T.; Guerrero, S. Arias; Lobão, A.Q.; Scharf, U.; Zamora, N.A.; Erkens, R.H.J.. |
A taxonomic revision of the genus Guatteria, including the former genera Guatteriella, Guatteriopsis and Heteropetalum is given. Within the genus Guatteria 177 species are recognized, 25 of which are new. Included are chapters on the history of the taxonomy of the genus, morphology, wood anatomy, karyology, palynology, chemistry, flower biology and pollination, dispersal, distribution and ecology, phylogeny and molecular studies, conservation, and uses. A synoptical key to all species is included, as well as two dichotomous keys, one for the species of Central America and Mexico, and one for the species of NE, E and SE Brazil. The species treatments include descriptions, full synonymy, geographical and ecological notes, vernacular names and taxonomic... |
Tipo: Article / Letter to the editor |
Palavras-chave: Annonaceae; Chemistry; Descriptions; Flower biology and pollination; Guatteria; Guatteriella; Guatteriopsis; Heteropetalum; History; Molecular studies; Morphology; Neotropics; Palynology; Phylogeny; Taxonomy; Vernacular names. |
Ano: 2015 |
URL: http://www.repository.naturalis.nl/record/588490 |
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Diogo,Rui. |
As noted Gould in his recent and last book «The structure of evolutionary theory», discourses on the high importance and frequency of evolutionary trends have consumed a great part of the research on the history of clades. Although aware that natural selection theoretically yields adaptation to immediate environments, many authors defend such trends as generalised improvements somehow conferring advantages across most or all experienced environments. The high importance given to evolutionary trends is questioned by Gould, who considers that such a high importance given to such evolutionary trends bears no necessary relationship to the relative frequency or casual weight of these events in evolution, but mainly to a major bias: trends tell histories, and... |
Tipo: Journal article |
Palavras-chave: Evolution; Morphology; Phylogeny; Siluriformes; Teleostei. |
Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022006000500016 |
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Ericson, P.G.P.. |
The paper summarizes the current understanding of the evolution and diversification of birds. New insights into this field have mainly come from two fundamentally different, but complementary sources of information: the many newly discovered Mesozoic bird fossils and the wealth of genetic analyses of living birds at various taxonomic levels. The birds have evolved from theropod dinosaurs from which they can be defined by but a few morphological characters. The early evolutionary history of the group is characterized by the extinctions of many major clades by the end of the Cretaceous, and by several periods of rapid radiations and speciation. Recent years have seen a growing consensus about the higher- level relationships among living birds, at least as... |
Tipo: Article / Letter to the editor |
Palavras-chave: Aves; Phylogeny; Systematics; Fossils; DNA; Genetics; Biogeography; 42.83. |
Ano: 2008 |
URL: http://www.repository.naturalis.nl/record/280479 |
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Richert, Laurent; Golubic, Stjepko; Le Guedes, Roland; Herve, Annie; Payr, Claude. |
Cyanobacterial populations, the primary producers and builders of 'kopara' microbial mats were studied in four selected ponds along the rim of the Rangiroa Atoll, French Polynesia using a polyphasic approach. Seven isolates were maintained in uni-cyanobacterial cultures, characterized morphotypically and phylogenetically by evaluating sequences of the 16S rRNA gene of about 620 base pairs in length. Cyanobacteria in natural populations were analyzed microscopically, characterized morphotypically, and compared with cultured strains. Three of the isolates were identified in the field samples: Lyngbya aestuarii, Johannesbaptistia pellucida and Chroococcus submarinus were present in the mats only as minor components, whereas the species of Schizothrix that... |
Tipo: Text |
Palavras-chave: 16S rRNA; Polyphasic approach; Phylogeny; Microbial mats; Microbial ecology; Kopara; Diversity; Cyanobacteria; Culture. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2050.PDF |
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Knapp, D.G.; Kovács, G.M.; Zajta, E.; Groenwald, J.Z.; Crous, P.W.. |
Dark septate endophytes (DSE) are distributed worldwide as root-colonising fungi, and frequent in environments with strong abiotic stress. DSE is not a taxon, but constitutes numerous fungal taxa belonging to several orders of Ascomycota. In this study we investigate three unidentified DSE lineages belonging to Pleosporales that were found previously in semiarid sandy grasslands. For molecular phylogenetic studies seven loci (ITS, partial 18S nrRNA, 28S nrRNA, actin, calmodulin, transcription-elongation factor 1-α and ß-tubulin genes) were amplified and sequenced. Based on morphology and the resulting molecular phylogeny these isolates were found to represent three novel genera within the Pleosporales, namely Aquilomyces, Flavomyces and Darksidea, with eight... |
Tipo: Article / Letter to the editor |
Palavras-chave: Dothideomycetes; Endophytes; Massarineae; Mating; Phylogeny; Sexual state; Taxonomy. |
Ano: 2015 |
URL: http://www.repository.naturalis.nl/record/588702 |
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Fahl,Willian Oliveira; Carnieli Jr,Pedro; Castilho,Juliana Galera; Carrieri,Maria Luiza; Kotait,Ivanete; Iamamoto,Keila; Oliveira,Rafael Novaes; Brandão,Paulo Eduardo. |
In Brazil, bats have been assigned an increasing importance in public health as they are important rabies reservoirs. Phylogenetic studies have shown that rabies virus (RABV) strains from frugivorous bats Artibeus spp. are closely associated to those from the vampire bat Desmodus rotundus, but little is known about the molecular diversity of RABV in Artibeus spp. The N and G genes of RABV isolated from Artibeus spp. and cattle infected by D. rotundus were sequenced, and phylogenetic trees were constructed. The N gene nucleotides tree showed three clusters: one for D. rotundus and two for Artibeus spp. Regarding putative N amino acid-trees, two clusters were formed, one for D. rotundus and another for Artibeus spp. RABV G gene phylogeny supported the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Rabies Bat Artibeus spp.; Desmodus rotundus; Phylogeny; Molecular epidemiology. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702012000600008 |
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L' Haridon, S; Reysenbach, A.l.; Tindall, B. J.; Schonheit, P; Banta, A; Johnsen, U; Schumann, P; Gambacorta, A; Stackebrandt, E; Jeanthon, C. |
Three thermophilic, anaerobic, strictly chemolithoautotrophic, sulphur- and/or thiosulphate-reducing bacteria, designated SL17(T), SL19(T) and SL22(T), were isolated from deep-sea hydrothermal samples collected at 13 degrees N (East Pacific Rise), Guaymas Basin (Gulf of California) and 23 degrees N (Mid-Atlantic Ridge), respectively. These strains differed in their morphology, temperature range and optimum for growth, energy substrates and 16S rRNA gene sequences. The G + C content of the genomic DNA was 41 mol% (SL22(T)), 42 mol% (SL17(T)) and 46 mol% (SL19(T)). Comparative analysis of phenotypic and phylogenetic traits indicated that strains SL17(T) and SL22(T) represented two novel species of the genus Desulfurobacterium and that strain SL19(T) should... |
Tipo: Text |
Palavras-chave: Hydrothermal environment; Phylogeny; Thermophiles; Bacteria. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2174.pdf |
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Registros recuperados: 404 | |
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