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101.
Enrique Isla Dieter Gerdes Sergio Rossi Ida Fiorillo Elisabet Sa?�� Josep-Maria Gili Wolf E. Arntz 《Polar Biology》2011,34(8):1125-1133
Biochemical characteristics of seafloor sediment off Austasen in the southeastern Weddell Sea were assayed in samples recovered
in the early autumn and late spring of 2000 and 2003, respectively. Sediment was separated in the grain-size fractions >200 μm
and <200 μm to distinguish biochemical characteristics in the fraction available for benthic suspension feeders (<200 μm).
In the bulk sediment, the lipid (LPD) and carbohydrate (CHO) contents were significantly different between seasons with higher
LPD content in the early autumn and higher CHO content in the late spring. In the grain-size fractions <200 μm, the LPD and
protein (PRT) contents were significantly higher in the early autumn meaning that in this season the fraction available for
benthic suspension feeders presented higher nutritive value. The relatively higher CHO concentrations observed in each fraction
in the late spring were attributed to refractory matter, whereas the higher PRT and LPD concentrations found during the early
autumn were associated with planktonic material settled after the summer phytoplankton bloom. Our results suggest that there
is seasonal variation in the composition of organic matter in the sediment, with better nutritive quality in the early autumn,
especially in the grain-size fraction available for benthic suspension feeders. These variations also suggest that the benthic
community exploits the fresh organic matter accumulated after the summer throughout the Antarctic dark months leaving the
sediment almost exhaust of LPD and with higher CHO contents, presumably of refractory nature, at the onset of the seasonal
phytoplankton bloom of the following year. 相似文献
102.
ABSTRACT: BACKGROUND: Traditional medicine (TM) occupies a special place in the management of diseases in Uganda. Not with standing the many people relying on TM, indigenous knowledge (IK) related to TM is getting steadily eroded. To slow down this loss it is necessary to document and conserve as much of the knowledge as possible. This study was conducted to document the IK relevant to traditional medicine in the districts of Mukono, Nakapiripirit, Kanungu and Pallisa, in Uganda. METHODS: An ethnobotanical survey was conducted between October 2008 and February 2009 using techniques of key informant interviews and household interviews. RESULTS: The common diseases and conditions in the four districts include malaria, cough, headache, diarrhea, abdominal pain, flu, backache and eye diseases. Respondents stated that when they fall sick they self medicate using plant medicines or consult western-trained medicine practitioners. Self medication using herbal medicines was reported mostly by respondents of Nakapiripirit and Mukono. Respondents have knowledge to treat 78 ailments using herbal medicines. 44 species, mentioned by three or more respondents have been prioritized. The most frequently used part in herbal medicines is the leaf, followed by the stem and root. People sometime use animal parts, soil, salt and water from a grass roof, in traditional medicines. Herbal medicines are stored for short periods of time in bottles. The knowledge to treat ailments is acquired from parents and grandparents. Respondents' age and tribe appears to have a significant influence on knowledge of herbal medicine, while gender does not. CONCLUSION: This survey has indicated that IK associated with TM stills exists and that TM is still important in Uganda because many people use it as a first line of health care when they fall sick. Age and tribe influence the level of IK associated with herbal medicine, but gender does not. 相似文献
103.
104.
The Biology and Economics of Coral Growth 总被引:1,自引:0,他引:1
Osinga R Schutter M Griffioen B Wijffels RH Verreth JA Shafir S Henard S Taruffi M Gili C Lavorano S 《Marine biotechnology (New York, N.Y.)》2011,13(4):658-671
To protect natural coral reefs, it is of utmost importance to understand how the growth of the main reef-building organisms—the
zooxanthellate scleractinian corals—is controlled. Understanding coral growth is also relevant for coral aquaculture, which
is a rapidly developing business. This review paper provides a comprehensive overview of factors that can influence the growth
of zooxanthellate scleractinian corals, with particular emphasis on interactions between these factors. Furthermore, the kinetic
principles underlying coral growth are discussed. The reviewed information is put into an economic perspective by making an
estimation of the costs of coral aquaculture. 相似文献
105.
Kogan Y Halevi-Tobias KE Hochman G Baczmanska AK Leyns L Agur Z 《The Biochemical journal》2012,444(1):115-125
The Wnt signalling pathway controls cell proliferation and differentiation, and its deregulation is implicated in different diseases including cancer. Learning how to manipulate this pathway could substantially contribute to the development of therapies. We developed a mathematical model describing the initial sequence of events in the Wnt pathway, from ligand binding to β-catenin accumulation, and the effects of inhibitors, such as sFRPs (secreted Frizzled-related proteins) and Dkk (Dickkopf). Model parameters were retrieved from experimental data reported previously. The model was retrospectively validated by accurately predicting the effects of Wnt3a and sFRP1 on β-catenin levels in two independent published experiments (R(2) between 0.63 and 0.91). Prospective validation was obtained by testing the model's accuracy in predicting the effect of Dkk1 on Wnt-induced β-catenin accumulation (R(2)≈0.94). Model simulations under different combinations of sFRP1 and Dkk1 predicted a clear synergistic effect of these two inhibitors on β-catenin accumulation, which may point towards a new treatment avenue. Our model allows precise calculation of the effect of inhibitors applied alone or in combination, and provides a flexible framework for identifying potential targets for intervention in the Wnt signalling pathway. 相似文献
106.
Maria-J. Uriz Josep-Maria Gili Covadonga Orejas Alicia-R. Perez-Porro 《Polar Biology》2011,34(2):243-255
Sponges are the dominant invertebrates in many Antarctic communities, where they play a decisive structural function thanks
to their abundance and large sizes. However, current knowledge on Antarctic sponges remains poor even with respect to basic
aspects such as taxonomy. Here, we report on an Antarctic species of the genus Stylocordyla, which has been recorded for a long time under the name of the boreal S. borealis due to spicule and growth habit similarities. A thorough study of dense populations of the only Stylocordyla species known up to now from the eastern zone of the Weddell Sea as well as the re-examination of several specimens (including
the type material) of S. borealis has allowed us to assess the variability of the boreal species and to confirm that the austral species is not S. borealis (Lovén, 1868) but a new species of Stylocordyla, different from the other congeners recorded from southern latitudes. The new species S. chupachups commonly dwells on horizontal or slighted sloped hard bottoms of the continental shelf of Weddell Sea, from 100 m to below
400 m depth, although the densest populations usually occur between 150 and 300 m. It is a pioneer species in areas that have
been scoured by icebergs, and thus its presence may be considered an indicator of recent colonisation. 相似文献
107.
108.
Hadas Prag Naveh Uma N. M. Rao Lisa H. Butterfield 《Pigment cell & melanoma research》2013,26(6):796-804
Melanoma is an ‘immunogenic tumor’, often highly infiltrated with lymphocytes, which are capable of inducing regression of the primary tumor. The commonly observed phenomenon of regression suggests substantial cross‐talk between immune cells and transformed melanocytes. An immune response to melanocyte differentiation antigens common to transformed and normal melanocytes manifests clinically at distant sites as melanoma‐associated vitiligo or halo nevi. Despite similar antigenic targets, the pathogenesis and prognosis differ between the different melanoma‐associated leukodermas. Understanding immunologic cross‐talk between melanocytes and the immune system will aid the development of approaches to combat melanoma. 相似文献
109.
110.
Pedro Gili Alfredo MederosEduardo Medina de la Rosa Alfonso Muñoz 《Inorganica chimica acta》2002,331(1):16-24
A computational study of chromium(VI) and (V) peroxides, which exhibit important genotoxic and mutagenic activity, is reported. Energies and equilibrium geometries for [CrVI(O)(O2)2(OH)]−, [CrVI(O)(O2)2(OH2)], [CrVI(O)(O2)2(py)], [CrVI(OH)(O2)2(OH2)]+, [CrV(O)(O2)2(OH2)]− and species were calculated using molecular mechanics calculations (MMFF94 and MM+), quantum calculations with semi-empirical methods (RHF and UHF/PM3) and density functional theory (pBP86/DN* or pBP/DN* and B3LYP/6-31G(d). Equilibrium geometries for the compounds [CrV(O2)3(OH)]2− and [CrV(O2)4]3− were determined by molecular mechanics. Vibrational frequencies, standard thermodynamic quantities and electronic spectra were calculated using B3LYP/6-31G(d). The structural relationship between all these species and an explanation of the formation of peroxo species in the acid-basic pH range are given. An experimental study of peroxo species in basic medium was also performed (synthesis, X-ray powder diffraction patterns and infrared spectra of the peroxo complexes isolated) but did not confirm the existence of a tri-peroxo complex in the solid phase. 相似文献