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991.
Hydraulic lift through transpiration suppression in shrubs from two arid ecosystems: patterns and control mechanisms 总被引:2,自引:0,他引:2
Iván Prieto Karina Martínez-Tillería Luis Martínez-Manchego Sonia Montecinos Francisco I. Pugnaire Francisco A. Squeo 《Oecologia》2010,163(4):855-865
Hydraulic lift (HL) is the passive movement of water through the roots from deep wet to dry shallow soil layers when stomata
are closed. HL has been shown in different ecosystems and species, and it depends on plant physiology and soil properties.
In this study we explored HL patterns in several arid land shrubs, and developed a simple model to simulate the temporal evolution
and magnitude of HL during a soil drying cycle under relatively stable climatic conditions. This model was then used to evaluate
the influence of soil texture on the quantity of water lifted by shrubs in different soil types. We conducted transpiration
suppression experiments during spring 2005 in Chile and spring 2008 in Spain on five shrub species that performed HL, Flourensia thurifera, Senna cumingii and Pleocarphus revolutus (Chile), Retama sphaerocarpa and Artemisia barrelieri (Spain). Shrubs were covered with a black, opaque plastic fabric for a period of 48–72 h, and soil water potential was recorded
at different depths under the shrubs. While the shrubs remained covered, water potential continuously increased in shallow
soil layers until the cover was removed. The model output indicated that the amount of water lifted by shrubs is heavily dependent
on soil texture, as shrubs growing in loamy soils redistributed up to 3.6 times more water than shrubs growing on sandy soils.
This could be an important consideration for species growing in soils with different textures, as their ability to perform
HL would be context dependent. 相似文献
992.
993.
Christa Maes Steven Goossens Sonia Bartunkova Benjamin Drogat Lieve Coenegrachts Ingrid Stockmans Karen Moermans Omar Nyabi Katharina Haigh Michael Naessens Lieven Haenebalcke Jan P Tuckermann Marc Tjwa Peter Carmeliet Vice Mandic Jean-Pierre David Axel Behrens Andras Nagy Geert Carmeliet Jody J Haigh 《The EMBO journal》2010,29(2):424-441
994.
995.
Massimo Gianotti Corrado Corti Sonia Delle Fratte Romano Di Fabio Colin P. Leslie Francesca Pavone Laura Piccoli Luigi Stasi Mark J. Wigglesworth 《Bioorganic & medicinal chemistry letters》2010,20(17):5069-5073
A novel imidazobenzazepine template (5a) with potent dual H1/5-HT2A antagonist activity was identified. Application of a zwitterionic approach to this poorly selective and poorly developable starting point successfully delivered a class of high quality leads, 3-[4-(3-R1-2-R-5H-imidazo[1,2-b][2]benzazepin-11-yl)-1-piperazinyl]-2,2-dimethylpropanoic acids (e.g., 9, 19, 20, and 21), characterized by potent and balanced H1/5-HT2A receptor antagonist activities and good developability profiles. 相似文献
996.
Elise Isabel Kevin P. Bateman Nathalie Chauret Wanda Cromlish Sylvie Desmarais Le T. Duong Jean-Pierre Falgueyret Jacques Yves Gauthier Sonia Lamontagne Cheuk K. Lau Serge Léger Tammy LeRiche Jean-François Lévesque Chun Sing Li Frédéric Massé Daniel J. McKay Christophe Mellon Deborah A. Nicoll-Griffith Renata M. Oballa M. David Percival W. Cameron Black 《Bioorganic & medicinal chemistry letters》2010,20(3):887-892
MK-0674 is a potent and selective cathepsin K inhibitor from the same structural class as odanacatib with a comparable inhibitory potency profile against Cat K. It is orally bioavailable and exhibits long half-life in pre-clinical species. In vivo studies using deuterated MK-0674 show stereoselective epimerization of the alcohol stereocenter via an oxidation/reduction cycle. From in vitro incubations, two metabolites could be identified: the hydroxyleucine and the glucuronide conjugate which were confirmed using authentic synthetic standards. 相似文献
997.
Sonia Gómez-Galera Eduard Rojas Duraialagaraja Sudhakar Changfu Zhu Ana M. Pelacho Teresa Capell Paul Christou 《Transgenic research》2010,19(2):165-180
Staple food crops, in particular cereal grains, are poor sources of key mineral nutrients. As a result, the world’s poorest
people, generally those subsisting on a monotonous cereal diet, are also those most vulnerable to mineral deficiency diseases.
Various strategies have been proposed to deal with micronutrient deficiencies including the provision of mineral supplements,
the fortification of processed food, the biofortification of crop plants at source with mineral-rich fertilizers and the implementation
of breeding programs and genetic engineering approaches to generate mineral-rich varieties of staple crops. This review provides
a critical comparison of the strategies that have been developed to address deficiencies in five key mineral nutrients—iodine,
iron, zinc, calcium and selenium—and discusses the most recent advances in genetic engineering to increase mineral levels
and bioavailability in our most important staple food crops. 相似文献
998.
Background
Taurine and zinc exert neurotrophic effects in the central nervous system. Current studies demonstrate that Na+/Cl- dependent neurotransmitter transporters, similar to that of taurine, are modulated by micromolar concentrations of zinc. This study examined the effect of zinc sulfate ex vivo on [3H]taurine transport in goldfish retina.Methods
Isolated cells were incubated in Ringer with zinc (0.1–100 µM). Taurine transport was done with 50 nM [3H]taurine or by isotopic dilution with taurine (0.001–1 mM) and 50 nM [3H]taurine.Results
Zinc reduced the capacity of taurine transport without changes in affinity, and caused a noncompetitive inhibition of high affinity taurine transport, with an EC50= 0.072 µM. The mechanism by which zinc affects taurine transport is unknown at the present.Conclusions
There may be a binding site of zinc in the transporter that affects union or translocation of taurine, or possibly the formation of taurine-zinc complexes, rather than free zinc, could affect the operation of the transporter.999.
1000.
Duong Thi Huong Giang Edilbert Van Driessche Isabel Vandenberghe Bart Devreese Sonia Beeckmans 《Fish & shellfish immunology》2010,28(5-6):743-753
From the serum of Pangasianodon hypophthalmus, two proteins were isolated by affinity chromatography on Sepharose and phosphorylcholine–Sepharose. Their binding on the affinity matrices critically depends on the presence of Ca2+ ions. N-terminal sequencing and sequencing of internal tryptic peptides identified the proteins as pentraxins and from their binding properties they are identified as SAP (serum amyloid P component) and CRP (C-reactive protein). Per ml serum, 36 μg SAP and 56 μg CRP was purified. Upon gel filtration, both the SAP and CRP elute as trimers of respectively 24 kDa and 28 kDa subunits. Both proteins are devoid of inter-chain disulfide bonds. Both SAP and CRP are glycosylated and agglutinate rabbit erythrocytes and pathogenic bacteria Edwardsiella ictaluri and Aeromonas hydrophila, but not Micrococcus lysodeikticus or Escherichia coli. Haemagglutination of SAP and CRP is inhibited by galactose (MIC = 1 mM) and by phosphorylcholine (MIC = 1–2 mM), respectively. Circular dichroism studies revealed that antiparallel β-pleated sheets are dominating the secondary structure. Upon removing the Ca2+ ions by EDTA, slight structural changes are observed by CD spectroscopy in the near-UV region. Immunodiffusion shows that P. hypophthalmus SAP and CRP do not cross-react. 相似文献