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151.
Callicott JB Rozzi R Delgado L Monticino M Acevedo M Harcombe P 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2007,362(1478):321-333
The perspective of 'biocomplexity' in the form of 'coupled natural and human systems' represents a resource for the future conservation of biodiversity hotspots in three direct ways: (i) modelling the impact on biodiversity of private land-use decisions and public land-use policies, (ii) indicating how the biocultural history of a biodiversity hotspot may be a resource for its future conservation, and (iii) identifying and deploying the nodes of both the material and psycho-spiritual connectivity between human and natural systems in service to conservation goals. Three biocomplexity case studies of areas notable for their biodiversity, selected for their variability along a latitudinal climate gradient and a human-impact gradient, are developed: the Big Thicket in southeast Texas, the Upper Botanamo River Basin in eastern Venezuela, and the Cape Horn Archipelago at the austral tip of Chile. More deeply, the biocomplexity perspective reveals alternative ways of understanding biodiversity itself, because it directs attention to the human concepts through which biodiversity is perceived and understood. The very meaning of biodiversity is contestable and varies according to the cognitive lenses through which it is perceived. 相似文献
152.
Barclay WS Jones IM Osborn HM Phillipson L Ren J Talevera GA Thompson CI 《Bioorganic & medicinal chemistry》2007,15(12):4038-4047
Influenza viruses attach to host cells by binding to terminal sialic acid (Neu5Ac) on glycoproteins or glycolipids. Both the linkage of Neu5Ac and the identity of other carbohydrates within the oligosaccharide are thought to play roles in restricting the host range of the virus. In this study, the receptor specificity of an H5 avian influenza virus haemagglutinin protein that has recently infected man (influenza strain A/Vietnam/1194/04) has been probed using carbohydrate functionalised poly(acrylic acid) polymers. A baculovirus expression system that allows facile and safe analysis of the Neu5Ac binding specificity of mutants of H5 HA engineered at sites that are predicted to effect a switch in host range has also been developed. 相似文献
153.
154.
Davit-Béal T Chisaka H Delgado S Sire JY 《Biological reviews of the Cambridge Philosophical Society》2007,82(1):49-81
Elucidation of the mechanisms controlling early development and organogenesis is currently progressing in several model species and a new field of research, evolutionary developmental biology, which integrates developmental and comparative approaches, has emerged. Although the expression pattern of many genes during tooth development in mammals is known, data on other lineages are virtually non-existent. Comparison of tooth development, and particularly of gene expression (and function) during tooth morphogenesis and differentiation, in representative species of various vertebrate lineages is a prerequisite to understand what makes one tooth different from another. Amphibians appear to be good candidates for such research for several reasons: tooth structure is similar to that in mammals, teeth are renewed continuously during life (=polyphyodonty), some species are easy to breed in the laboratory, and a large amount of morphological data are already available on diverse aspects of tooth biology in various species. The aim of this review is to evaluate current knowledge on amphibian teeth, principally concerning tooth development and replacement (including resorption), and changes in morphology and structure during ontogeny and metamorphosis. Throughout this review we highlight important questions which remain to be answered and that could be addressed using comparative morphological studies and molecular techniques. We illustrate several aspects of amphibian tooth biology using data obtained for the caudate Pleurodeles waltl. This salamander has been used extensively in experimental embryology research during the past century and appears to be one of the most favourable amphibian species to use as a model in studies of tooth development. 相似文献
155.
The identification of regulatory T (Treg) cells as important regulators of self-tolerance has opened up new therapeutic avenues for the treatment of several human diseases associated with Treg dysfunction, including autoimmune diseases and transplantation. Recent evidence indicates that vasoactive intestinal peptide (VIP), an anti-inflammatory neuropeptide with therapeutic potential in various immune disorders, participates in maintaining immune tolerance by a novel mechanism of inducing the generation of Treg cells. We propose a Treg-cell-based immunotherapy approach for resetting the balance of immune homeostasis, which takes advantage of novel functions of VIP in immunoregulation. 相似文献
156.
The aim of this work was to characterize starch polysaccharides using asymmetrical flow field flow fractionation coupled with multiangle laser light scattering. Amylopectins from eight different botanical sources and rabbit liver glycogen were studied. Amylopectins and glycogen were completely solubilized and analyzed, and high mass recoveries were achieved (81.7-100.0%). Amylopectin Mw, RG, and the hydrodynamic coefficient nuG (the slope of the log-log plot of RGi vs Mi) were within the ranges 1.05-3.18 x 10(8) g mol(-1), 163-229 nm, 0.37-0.49, respectively. The data were also considered in terms of structural parameters. The results were analyzed by comparison with the theory of hyperbranched polymers (Flory, P. J. Principles of Polymer Chemistry; Cornell University Press: Ithaca, NY, 1953; Burchard, W. Macromolecules, 1977, 10, 919-927). This theory, based upon the ABC model, has been shown to underestimate the branching degrees of amylopectins. However, quantitative agreement with the data in the literature was found for amylopectins when using the ABC model modified by the introduction of a multiplying factor, determined from previously described amylopectin structures in terms of the number of branching point calculations. 相似文献
157.
158.
Furlan Lopes Cassiane Lemos Costa Alice Dionísio Jaqueline Fernanda Delgado Cañedo Andres da Rosa Renata Del Valle Garnero Analia Inacio Ribeiro José Ricardo Gunski Ricardo José 《Genetica》2022,150(5):235-246
Genetica - Known as "electric-light bugs", belostomatids potentially act as agents of biological control. The Belostoma genus has holokinetic chromosomes, interspecific variation in... 相似文献
159.
Inés Urquiaga Sonia D’Acu?a Druso Pérez Sara Dicenta Guadalupe Echeverría Attilio Rigotti Federico Leighton 《Biological research》2015,48(1)