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排序方式: 共有459条查询结果,搜索用时 15 毫秒
181.
182.
Towards the identification of ecological management units: A multidisciplinary approach for the effective management of bottlenose dolphins in the southern Iberian Peninsula
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Joan Giménez Marie Louis Enrique Barón Francisco Ramírez Philippe Verborgh Pauline Gauffier Ruth Esteban Ethel Eljarrat Damià Barceló Manuela G. Forero Renaud de Stephanis 《水产资源保护:海洋与淡水生态系统》2018,28(1):205-215
183.
Survival and growth of geoduck clam larvae (Panopea generosa) in flow‐through culture tanks under laboratory conditions
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Gabriel Enrique Nava‐Gómez Zaúl Garcia‐Esquivel Eugenio Carpizo‐Ituarte Tatiana N Olivares‐Bañuelos 《Aquaculture Research》2018,49(1):294-300
The geoduck clam, Panopea generosa, is a species from the west coast of Baja California, Mexico, and the optimization of seed production systems is still a limiting factor for its aquaculture. In this study, a flow‐through culture system was designed and tested in P. generosa larvae. Survival and growth was compared in triplicate 45‐L fiberglass tanks using three larval densities (5, 10 and 15 larvae/ml). A head tank kept constant the water inflow, with a daily renewal rate of 1.8× tank volume. The food (Isochrysis spp.) was dosed according to the ingestion rate of larvae and the dilution rate. Survival decreased linearly during the first 10 days and reached asymptotic values of ca. 20% (15 larvae/ml) and 50% (densities of 5 and 10 larvae/ml) afterwards. Mean shell length at the end of the experiment (243 ± 1.8 to 270 ± 0.7 μm) was not statistically different among treatments, even though a trend towards higher gross growth rate was observed in the treatment with the lowest density (9.5 μm/day) relative to the rest of the treatments (8.5 μm/day). It is concluded that P. generosa larvae can be successfully grown in flow‐through systems at maximum densities of 10 larvae/ml without significantly affecting their survival and growth rates. The system design was reliable, kept a constant water flow with reduced maintenance, and may represent an important option in the laboratory for increasing the stocking density of Panopea species during the larval phase. 相似文献
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Nicolas Rispail Péter Kaló György B. Kiss T.H. Noel Ellis Karine Gallardo Richard D. Thompson Elena Prats Estibaliz Larrainzar Ruben Ladrera Esther M. González Cesar Arrese-Igor Brett J. Ferguson Peter M. Gresshoff Diego Rubiales 《Field Crops Research》2010
Faba bean is an excellent candidate crop to provide nitrogen input into temperate agricultural systems. However, its growth is hampered by several factors including environmental stresses and the presence of anti-nutritional factors. To solve these limitations, breeding programs have been initiated that were successful for monogenic traits but not so for multigenic traits. The large genome size of faba bean has slowed down breeding processes. Several other legumes have emerged as model legumes including Medicago truncatula, Lotus japonicus, Glycine max and Pisum sativum. The establishment of these models has already boosted our understanding of important processes such as the nitrogen-fixing symbiotic interaction. The high level of synteny and collinearity existing between legumes makes possible the transfer of key knowledge from model legumes to faba bean. Here we review the most recent knowledge gained from model legumes on grain quality, resistance to biotic and abiotic stresses, nitrogen-fixing symbiosis and how this knowledge can be employed for faba bean breeding. 相似文献
186.
Royuela E Sánchez-Fauquier A 《Comparative immunology, microbiology and infectious diseases》2010,33(1):1-14
The open reading frame 2 (ORF2) of human astrovirus (HAstV) encodes the structural VP26 protein that seems to be the main antigenic viral protein. However, its functional role remains unclear. Bioinformatic predictions revealed that VP29 and VP26 proteins could be involved in virus-cell interaction. In this study, we describe for the first time the cloning and expression in Escherichia coli (E. coli) of a recombinant VP26 (rVP26) protein and a VP26 C-terminal truncated form (VP26 Delta C), followed by purification by NTA-Ni(2+) agarose affinity chromatography. Protein expression and purification were evaluated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot (WB). Then, the purified proteins were evaluated for antigenic properties in enzyme linked immunosorbent assay (ELISA) using a polyclonal antibody (PAb) and a neutralizing monoclonal antibody (nMAb) named PL2, both of them directed to HAstV. The results presented herein indicate that the C-terminal end of the VP26 protein is essential to maintain the neutralizing epitope recognized by nMAb PL2 and that the N-terminus of VP26 protein may contain antigenic lineal-epitopes recognized by PAb. Thus, these recombinant proteins can be ideal tools for further antigenic, biochemical, structural and functional VP26 protein characterization, in order to evaluate its potential role in immunodiagnosis and vaccine studies. 相似文献
187.
Enrique Andivia Manuel Fernández Javier Vázquez-Piqué Aranzazu González-Pérez Raúl Tapias 《European Journal of Forest Research》2010,129(1):5-12
The knowledge of the cycle of nutrients is fundamental for the correct comprehension of the tree–soil relationship and for
an adequate forest management. In order to analyse the nutrients return from leaves and litterfall in a Mediterranean cork
oak forest in southwestern Spain, 12 trees were randomly selected and litterfall collected for 2 years. Samples were taken
monthly and separated in different fractions (leaves, twigs, catkins, acorns and miscellaneous), then leaves nutrients were
analyzed. Simultaneously, we analyzed the nutrient content of living leaves from the same trees in each season during 1 year.
The analyzed nutrients were C, N, P, K, Ca, Mg, Fe, Mn, S, Cu, Zn and Mo. Annual patterns of each nutrient in fallen leaves
were characterized and compared with seasonal values of these nutrients in living leaves. Leaves fall has two annual maximum,
first and most important in spring around April coinciding with renewal of foliar cover and second around October. Main concentration
patterns of N, P and K are related with phenological patterns, in consequence minimum concentration in leaves fall were obtained
in periods of growing and maximum litterfall. Concentrations of Ca, Fe and Mn increase with the age of the leaves and maximum
concentrations were obtained before periods of maximum litterfall while concentrations of Cu, Mo and Mg stay stable. Seasonal
analysis of nutrients in living leaves collected from the same trees in four different periods of the year allowed to corroborate
the patterns of leaves fall and the probable osmotic function of K. 相似文献
188.
A. Zidi J.M. Serradilla J. Jordana J. Carrizosa B. Urrutia O. Polvillo P. González-Redondo D. Gallardo M. Amills V.M. Fernández-Cabanás 《Domestic animal endocrinology》2010
In the lactating mammary gland, prolactin (PRL) stimulates the synthesis of lactose as well as fatty acid uptake, lipogenesis, and triacylglycerol synthesis. Associations between bovine PRL receptor (PRLR) genotype and fat yield have been reported, which illustrates the role of PRL in conveying lipids toward the udder as well as in stimulating their local synthesis during lactation. Conversely, and to the best of our knowledge, the effects of PRLR genotype on milk fatty acid content have not been studied so far in any mammalian species. In this study, we sequenced most of the coding region of the caprine PRLR gene in several individuals from the Malagueña and Murciano-Granadina breeds. This approach allowed us to identify 2 long and short mRNA isoforms, produced by alternative splicing, and 4 single-nucleotide polymorphisms (SNPs), namely, c.177T>C, c.1131G>A, c.1201G>A and c.1355C>T. Two of these SNPs are nonsynonymous and involve G401R (c.1201G>A) and T452I (c.1355C>T) amino acid substitutions in the cytoplasmic domain of PRLR, which plays a fundamental role in signal transduction. Performance of an association analysis with milk composition traits in a Murciano-Granadina goat population revealed highly suggestive effects on palmitoleic acid content, whereas suggestive effects were detected for other fatty acids, such as palmitic and linoleic. These results are consistent with the pleiotropic effects of PRL on mammary gland lipid metabolism and milk composition. 相似文献
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190.