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61.
62.
Célio?Magalh?esEmail author Sérgio Luiz S.?Bueno Georgina?Bond-Buckup Wagner Cotroni?Valenti Humberto L. Melo da?Silva Fábio?Kiyohara Emerson C.?Mossolin Sérgio S.?Rocha 《Biodiversity and Conservation》2005,14(8):1929-1945
Based on recent surveys of the freshwater decapod fauna, distributional data of five exotic species of freshwater decapod crustaceans for the hydrographic basins of the state of São Paulo are presented, as part of a large initiative for a comprehensive survey of the state’s biodiversity (BIOTA-FAPESP Program). These species are the North American crayfish Procambarus clarkii (Girard) (Cambaridae), the crab Dilocarcinus pagei Stimpson (Trichodactylidae) from the Amazon and Paraguay/lower Paraná River Basins, and the palaemonid shrimps Macrobrachium rosenbergii (De Man), from the Indo-Pacific region, Macrobrachium amazonicum (Heller) and Macrobrachium jelskii (Miers), both from the Orinoco, Amazon and the Paraguay/lower Paraná River Basins. Possible modes by which their introduction might have occurred are commented upon and potential consequences are discussed. 相似文献
63.
Zayas-Pérez H Tello-Solís SR González-Márquez H Bonilla-González E Mendoza-Hernández G Betancourt-Rule M 《Protein and peptide letters》2005,12(3):299-303
We have purified and characterized pig and bovine milk lactadherins. Studies by circular dichroism spectroscopy indicate that the two proteins present a similar folding pattern. Results have been discussed in terms of their affinity for pig zona pellucida in order to use these proteins as analogs of pig sperm lactadherin in gamete studies. 相似文献
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Rojas G Lamdan H Padron S Munoz Y Ayala M Gavilondo JV 《Biochemical and biophysical research communications》2005,336(4):1207-1213
We have constructed a highly useful phage-displayed human antibody repertoire with limited cloning efforts. Our strategy was to maximize diversity during the first steps of library construction through the use of various lymphoid sources from several donors, inclusion of different immunoglobulin isotypes, and performance of multiple separate amplification reactions with all possible combinations within a complex primer set. The resulting variable region collections were cloned to form a moderate size library, composed by 4.25x10(8) single chain antibody fragments. This repertoire was successfully used to retrieve binders to seven model antigens: six proteins and one 12 aa peptide. Binding affinities reached nanomolar and even subnanomolar range. Sequence diversity and V-gene usage variability among binders were proven. Our approach was not focused on absolute library size, but on a high quality sampling of variable regions from the human antibody repertoire. 相似文献
67.
Arboleda H Arboleda G 《Birth defects research. Part A, Clinical and molecular teratology》2005,73(8):562-568
BACKGROUND: Wiedemann-Rautenstrauch syndrome (WRS) characterizes a neonatal progeroid entity. In the last 30 years, 28 cases have been reported. In most cases of WRS, survival is short and long-term studies are impossible. CASE: In the present report, we describe a patient with WRS followed for 17 years at the Instituto de Genética, Universidad Nacional de Colombia; this is an exceptional survival period for a person with WRS. The information collected through 17 years for the present patient provides new knowledge about the natural evolution of this syndrome. New clinical and laboratory characteristics are compared with those reported for Rautenstrauch's patient "G." CONCLUSIONS: Our results confirm the variability of this syndrome, especially at the neurological level. However, many etiological and pathological aspects of this syndrome remain unknown. 相似文献
68.
Mukdsi JH De Paul AL Gutiérrez S Roth FD Aoki A Torres AI 《Journal of molecular histology》2005,36(8-9):447-454
Summary Vascular endothelial growth factor (VEGF) is an important angiogenic factor in the pituitary gland. The objective of this
study was to unveil the VEGF subcellular localisation in different pituitary cell types and to evaluate changes in its expression
at different time intervals after oestrogen stimulation. A relevant feature demonstrated was the identification of this cytokine
in the nucleus and cytoplasm of lactotrophs, somatotrophs and gonadotrophs, as well as in follicle-stellate cells of male
rats. Oestrogen treatment increased the number of VEGF immunopositive cells and its expression detected differentially by
western blot in both nucleus and cytoplasm of pituitary cells when compared to the control. At ultrastructural level VEGF
appeared associated with nucleolus and euchromatin involving a possible internal autocrine loop. In lactotrophs, the predominant
cell of the tumour, VEGF was immunodetected in RER, Golgi complex, and vesicular organelles, supporting further the association
with an auto-paracrine effect exerted by VEGF. The nucleus/cytoplasm ratio of VEGF revealed a prevalent accumulation of VEGF
in the cytoplasm. The presence of VEGF in the nucleus may probably be associated with a translocation to this cell compartment.
This study demonstrated a cytoplasmic and nuclear immunolocalisation of VEGF in normal and tumoural adenohypophyseal cells.
In the course of prolactinoma development, the oestrogen stimulated VEGF expression in tumoural cells, promoting a vascular
adaptation which contributes to growth and progression of the tumour. 相似文献
69.
Predicting future plant and ecosystem responses to elevated CO(2) also requires an understanding of the role of other factors, especially soil nitrogen. This is particularly challenging for global aridlands where total N and the relative amounts of nitrate and ammonia vary both spatially and seasonally. We measured gas exchange and primary and secondary C metabolites in seedlings of two dominant aridland shrub species (Prosopis flexuosa [S America] and P. glandulosa [N America]) grown at ambient (350 ppm) or elevated (650 ppm) CO(2) and nitrogen at two levels (low [0.8 mM] and high [8.0 mM]) and at either 1 : 1 or 3 : 1 nitrate to ammonia. Whereas elevated CO(2) increased assimilation rate, water use efficiency, and primary carbon metabolites in both species, these increases were strongly contingent upon nitrogen availability. Elevated CO(2) did not increase secondary metabolites (i.e., phenolics). For these important aridland species, the effects of elevated CO(2) are strongly influenced by nitrogen availability and to a lesser extent by the relative amounts of nitrate and ammonia supplied, which underscores the importance of both the amount and chemical composition of soil nitrogen in mediating the potential responses of seedling growth and establishment of aridland plants under future CO(2)-enriched atmospheres. 相似文献
70.
Chaetognaths are among the most abundant predators in the Southern Ocean and are potentially important components in the biological
carbon pump due to the production of large, fast-sinking fecal pellets. In situ S. gazellae abundance, fecal pellet production, sinking rates, carbon content, and vertical carbon fluxes were measured at the Lazarev Sea between
December 2005 and January 2006. Sagitta gazellae produce fecal pellets that sink at speeds of 33–600 m day−1 and have carbon contents of 0.01–0.8 mg C pellet−1. Vertical carbon flux was later compared with the total carbon flux measured at 360 m depth at the study area. Rough estimates
using published seasonal abundance of S. gazellae indicate that, at 360 m depth in the Lazarev Sea, this specie may contribute 12 and 5% of the total vertical carbon flux
in winter (ice-covered) and summer (ice-free), respectively. Thus, the role of chaetognaths in the downward transport of organic
matter may be far more important than previously thought. 相似文献