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61.
The integration of alien plants in mutualistic plant–hummingbird networks across the Americas: the importance of species traits and insularity 下载免费PDF全文
Pietro K. Maruyama Jeferson Vizentin‐Bugoni Jesper Sonne Ana M. Martín González Matthias Schleuning Andréa C. Araujo Andrea C. Baquero Juliana Cardona Paola Cardona Peter A. Cotton Glauco Kohler Carlos Lara Tiago Malucelli Oscar Humberto Marín‐Gómez Jeff Ollerton Ana M. Rui Allan Timmermann Isabela G. Varassin Thais B. Zanata Carsten Rahbek Marlies Sazima Bo Dalsgaard 《Diversity & distributions》2016,22(6):672-681
62.
Tetyana Chumak Lukas Rüttiger Sze Chim Lee Dario Campanelli Annalisa Zuccotti Wibke Singer Jiří Popelář Katja Gutsche Hyun-Soon Geisler Sebastian Philipp Schraven Mirko Jaumann Rama Panford-Walsh Jing Hu Thomas Schimmang Ulrike Zimmermann Josef Syka Marlies Knipper 《Molecular neurobiology》2016,53(8):5607-5627
63.
Mauricio Fernández Otárola Marlies Sazima Vera N. Solferini 《Trees - Structure and Function》2016,30(6):2041-2049
Key message
Congeneric species showed similar stem and crown allometry, but differed in crown dimensions indicating that crown size is adaptive and variable despite mechanical restrictions.Abstract
Morphological adaptations favor differential use of the space in tropical trees, but the variability in stem and crown allometry can be constrained by phylogenetic and mechanical factors. In addition, dioecious species show marked differences in their energy requirements related to reproduction, but little information is available about the role of shape and allometry on differential acquisition of energy between the sexes. We studied the stem and crown dimensions of congeneric dioecious trees to determine if there are: (i) differences in the allometry between the sexes, (ii) different average sizes among sympatric species, and (iii) differences in stem and crown allometry between sympatric and allopatric species. Two pairs of sympatric Virola (Myristicaceae) in Brazil and Costa Rica were studied. SMA regression models were used to investigate allometric relationships between diameter at breast height (DBH) and tree height, and between DBH and crown volume (CV). No sexual dimorphism in stem and crown morphology was observed in this study, indicating that differences in resource allocation for reproduction between the sexes do not impact the stem and crown structure in these species. Overall, low variability among the species was observed. Only one species differed in stem allometry and none differed in crown allometry. CV differed between sympatric species. Stem and crown allometry are related to structural stability and our results support similar mechanical restriction for these species. The ecological significance of differences in CV among canopy species remains to be explored.64.
Marlies Fischer Mandeep Kang Nicholas Pj Brindle 《Protein science : a publication of the Protein Society》2016,25(2):352-359
Directed evolution is a powerful tool for engineering protein function. The process of directed evolution involves iterative rounds of sequence diversification followed by assaying activity of variants and selection. The range of sequence variants and linked activities generated in the course of an evolution are a rich information source for investigating relationships between sequence and function. Key residue positions determining protein function, combinatorial contributors to activity and even potential functional mechanisms have been revealed in directed evolutions. The recent application of high throughput sequencing substantially increases the information that can be retrieved from directed evolution experiments. Combined with computational analysis this additional sequence information has allowed high‐resolution analysis of individual residue contributions to activity. These developments promise to significantly enhance the depth of insight that experimental evolution provides into mechanisms of protein function. 相似文献
65.
66.
Reduced expression of chemerin in visceral adipose tissue associates with hepatic steatosis in patients with obesity 下载免费PDF全文
67.
Ronald E. Bontrop Marcel G. J. Tilanus Marlies M. A. Mikulski Dienne G. Elferink Annemarie Termijtelen Rene R. P. de Vries Jon J. van Rood Marius J. Giphart 《Immunogenetics》1988,27(1):40-45
HLA-DR molecules were isolated from HLA-DR3, –5, and –w6 positive homozygous B-cell lines by immunoprecipitation with monoclonal antibodies and analyzed by gel electrophoretic techniques. DNA isolated from the same cell lines was digested with the restriction enzyme Taq I and hybridized with a DR beta full-length cDNA probe. We demonstrated that certain DR
I alleles are found in combination with different DR
III alleles as defined by Southern blotting, protein chemistry, a functional assay using purified protein derivative-specific T-cell lines, and, in one case, also alloreactive T-cell reagents. Our results indicate that within the family of HLA-DRw52-associated haplotypes DR beta chain genes may have been transferred from one haplotype to another. The implications of these findings are discussed. 相似文献
68.
Summary The opisthonephric kidney of the rainbow trout was investigated by light- and electron microscopy and a fluorescent-histochemical technique for biogenic amines was used. Preglomerular sphincters at the origin of afferent arterioles are present in this euryhaline teleost. The branching point of the afferent arteriole is characterized by (i) the formation of a right angle with the parent vessel, (ii) circularly arranged smooth muscle cells of the tunica media, (iii) additional circularly arranged smooth muscle cells intercalated between endothelium and tunica media, and (iv) a collar-like arrangement of several large endothelial cells with elaborate marginal folds and abundant myoendothelial junctions. A dense adrenergic innervation displaying specific fluorescence was found along the terminal arterioles and afferent arterioles, and conspicuously at the preglomerular sphincters. These results are suggestive of a neural participation in kidney function. They are discussed on the basis of recent evidence from pharmacological and physiological experiments for neural involvement in glomerular intermittency. 相似文献
69.
Pollination Biology of Piperaceae Species in Southeastern Brazil 总被引:3,自引:2,他引:1
Phenology, floral biology and breeding system are describedfor 14 Piperaceae species at two sites covered by semi-deciduousforest in southeastern Brazil. Flowering occurred continuouslythroughout the year, with a peak during the windy months. Allspecies had minute odorous and nectarless flowers visited byinsects; five of them showed a substantial degree of self-compatibility,and one was andromonoecious. Seven species were wind pollinated,and three were exclusively pollinated by insects. Flower visitorswere mainly hoverflies and bees. Copyright 2000 Annals of BotanyCompany Piper spp., Ottonia spp., Pothomorphe umbellata, pepper family, phenology, floral biology, breeding system, ambophily, semi-deciduous forest 相似文献
70.