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| Registros recuperados: 67 | |
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| Beiras, Ricardo; His, Edouard. |
| The effects of mercury (Hg) concentrations ranging from 0 (control) to 1024 µg 1-1 upon embryogenesis, survival, growth and metamorphosis of Crassostrea gigas (Thunberg) oyster larvae were investigated. Embryogenesis was abnormal in 50 % of the individuals at 11 µg 1-1 . The 48 h LD50 for D·shaped, umbonate and pediveliger larvae were 33, 115 and 200 µg 1-1 respectively. The increase in LD50 was partially explained by the larval weight increase, although weight-specific tolerance to Hg was higher in smaller larvae. Growth, the most sensitive physiological process studied, was significantly retarded at 4 µg 1-1. The metamorphosis rate was significantly reduced when competent pediveligers were exposed to 64 µg 1-1 for 48 h prior to the addition of the... |
| Tipo: Text |
Palavras-chave: Mercury; Oyster; Larvae; Embryo; Bioassay; Ecotoxicology; Crassostrea gigas. |
| Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/00037/14867/12191.pdf |
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| Beiras, R; His, Edouard. |
| The effects of Hg concentrations ranging from 0 (control) to 1024 mu g l(-1) upon embryogenesis, survival and growth of Mytilus galloprovincialis mussel larvae were investigated. Embryogenesis was abnormal in 50% of the individuals at 10 mu g l(-1). The 48 h LC(50) for D-shaped, early umbonate, late umbonate and eyed larvae were 51, 164, 322 and 383 pg l(-1) respectively. The LC(50) was an allometric function of ash-free dry weight with exponent b = 0.60. Larval growth was significantly reduced after 6 d exposure to 4 mu g Hg l(-1) and after 10 d exposure to 2 mu g l(-1). No significant differences in lethal or sublethal sensitivity to Hg were found between M. galloprovincialis and previously studied Crassostrea gigas embryos and larvae. The implications... |
| Tipo: Text |
Palavras-chave: Mercury; Mytilus; Mussel; Larva; Growth; Embryo; Bioassay; Ecotoxicology. |
| Ano: 1995 |
URL: http://archimer.ifremer.fr/doc/00258/36946/35665.pdf |
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| Borçato,Fábio Luiz; Bazzoli,Nilo; Sato,Yoshimi. |
| Mature males and females of Leporinus piau (Fowler, 1941) were induced to reproduce through a hypophysation process. Extrusion occurred 12 h or 312 hours-degree after the hypophysation, at a water temperature of 26°C. Fertilized eggs were maintained in incubators at 24°C. Embryonic development, was evaluated using every 10 minutes, fresh egg samples which were analyzed under stereoscopic microscope. The larvae were collected at 24-hour intervals for seven days after hatching, fixed in Bouin's fluid and were submitted to routine histological techniques. The eggs of L. piau were slightly gray, non-adhesive and round-shaped. After 1.5 h the embryo was at the 64-blastomere phase and showed a wide yolk region on the vegetative pole. Within 6.25 h, blastopore... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Embryo; Induced spawn; Teleost fish. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752004000100019 |
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| Pradillon, F; Le Bris, Nadine; Shillito, B; Young, C; Gaill, F. |
| Dispersal and colonisation processes at deep-sea vents are still not fully understood, essentially because early life stages of vent species remain unknown. The polychaete worm Alvinella pompejana forms colonies on chimney walls at East Pacific Rise vent sites where the temperature can frequently exceed 20 degrees C. In vitro studies in pressure vessels showed that the early embryos tolerate temperatures in a lower range (10-14 degrees C), suggesting that they would have to escape the colony to develop. Pressure vessels offer the advantage that each parameter can be independently controlled, but they do not simulate the more complex and dynamic conditions naturally encountered at vent sites. Accordingly, in addition to incubations in pressure vessels, we... |
| Tipo: Text |
Palavras-chave: Environmental condition; H2S; Temperature tolerance; Polychaete; Pressure vessel; Embryo; Development; Hydrothermal vent. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-600.pdf |
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| Araújo,M.C.C.; Vale Filho,V.R.; Ferreira,A.M.; Sá,W.F.; Barreto Filho,J.B.; Camargo,L.S.A.; Serapião,R.V.; Silva,M.V.G.B.. |
| The effect of cryopreservation in IFN-tau, from bovine embryos produced in vitro was evaluated. Two treated groups (G1= fresh bovine embryos, n=59 and G2= freezed embryos, n=84) were used to study the effect of cryopreservation on IFN-tau secretion. After reaching the blastocyst phase, the embryos were kept on individual culture for additional period of 7 days. On days 3 and 7 after the beginning of embryos cultivation, samples of the media culture were taken for IFN-tau secretion titration. Oocysts taken from follicles ranging from 3 to 5mm in diameter were obtained from ovaries of females at slaughterhouse. The embryos were frozen, after being dehydrated with ethylene glycol (1.8m), conditioned on 0.5ml palletes and frozen. Frozen embryos secreted lower... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bovine; Embryo; PIV; Interferon-tau. |
| Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352005000600008 |
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| Cerqueira,Vinicius Ronzani. |
| Eggs of the Southern Brazilian flounder Paralichthys orbignyanus were obtained through spawning induction and reared in laboratory. The eggs released were free-floating or pelagic. Other important characteristics were: spherical shape, smooth chorion, narrow perivitelline space, and a single oil globule. Egg and oil globule diameter were about 0.792 ± 0.008 mm and 0.114 ± 0.003 mm, respectively. The blastodisc was observed approximately 1 h after fertilization and followed by blastodisc cleavage. Blastula stage started after about 5 h and gastrula stage after 9 h. Approximately 20 h after fertilization, blastopore closure was observed. Neurula or early embryo occurred after 24 h. Cardiac beats and movements of the free embryonic tail were recorded after 40... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Flounder; Paralichthys orbignyanus; Egg; Embryo; Development. |
| Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132005000300016 |
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| Cordeiro,Maria Cristina Rocha; Pinto,Alberto Carlos Queiróz; Ramos,Víctor Hugo Vargas; Faleiro,Fábio Gelape; Fraga,Lilia Marta Santos. |
| Mango can be propagated by seeds or by grafting. For commercial purpose, grafting is the most appropriate method because it maintains the genetic characters from the propagated variety. To obtain grafted mango it is important to use polyembryonic varieties as rootstock since they produce a zygotic and many nucellar plantlets. The nucellar plantlets maintain the genetics of the mother-plant thus, are preferred for grafting since they supposedly give more uniformity to the orchard. In general, nurserymen use the most vigorous plantelet to graft, believing that they are nucellar. But, orchard disuniformities on height and yield are very common among mango trees of commercial orchards in Northeast region. The objective of this paper was to identify the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Plantlet identification; Embryo; Rootstock; Orchard uniformity. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452006000300025 |
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| Egonmwan,Rosemary I.. |
| The late stages of embryogenesis in the achatinid land snail Limicolariaflammea (Müller, 1774) were described using light and electron microscopy. Embryos at various stages of development were present in the eggs during the first hour after they were laid, from 4-cell blastulae to morulae and fairly advanced stages. The advanced embryo which was fully developed on the second day bears a long cephalic sac, first to be developed, attached to the embryo and a podocyst which is attached to the foot of the embryo. Both of these structures are reduced in size as embryogenesis progresses until they finally disappear at about the 7th day after the egg was deposited. The embryonic shell was apparent on the second day and spiral coiling was apparent at about day 5.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cephalic sac; Embryo; Embryonic shell; Foot; Podocyst. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752007000200022 |
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| Registros recuperados: 67 | |
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