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31.
C. A. M. van Turnhout R. S. E. W. Leuven A. J. Hendriks G. Kurstjens A. van Strien R. P. B. Foppen H. Siepel 《河流研究与利用》2012,28(3):269-282
To improve the ecological functioning of riverine ecosystems, large‐scale floodplain rehabilitation has been carried out in the Rhine–Meuse Delta since the 1990s. This paper evaluates changes in abundance of 93 breeding bird species over a period of 10 years in response to rehabilitation, by comparing population changes in 75 rehabilitated sites with 124 non‐rehabilitated reference sites. Such quantitative, multi‐species, large‐scale and long‐term evaluations of floodplain rehabilitation on biodiversity are still scarce, particularly studies that focus on the terrestrial component. We try to understand the effects by relating population trends to ecological and life‐history traits and strategies of breeding birds. More specifically, we try to answer the question whether rehabilitation of vegetation succession or hydro‐geomorphological river processes is the key driver behind recent population changes in rehabilitated sites. Populations of 35 species have significantly performed better in rehabilitated sites compared to non‐rehabilitated floodplains, whereas only 8 have responded negatively to rehabilitation. Differences in effects between species are best explained by the trait selection of nest location. Reproductive investment and migratory behaviour were less strong predictors. Based on these three traits we defined eight life‐history strategies that successfully captured a substantial amount of variation in rehabilitation effects. We conclude that spontaneous vegetation succession and initial excavations are currently more important drivers of population changes than rehabilitation of hydrodynamics. The latter are strongly constrained by river regulation. If rehabilitation of hydro‐geomorphological processes remains incomplete in future, artificial cyclic floodplain rejuvenation will be necessary for sustainable conservation of characteristic river birds. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Quality Improvement of Granular Wastes-The Effective Way to Recycle Secondary Raw Building Materials
邢伟宏 《武汉理工大学学报(材料科学英文版)》2004,19(4)
1 IntroductionTherearefourmaintypesofgranularwastematerialslistedinTable 1.Constructionanddemolitionwaste(CDW )arefromtheconstruction ,remodelling ,repairinganddemolishingofbuildingsandotherstructures .Ashesaretheresiduesfromburningofwood ,coal ,andother… 相似文献
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DA Hullett MT Cantorna C Redaelli J Humpal-Winter CE Hayes HW Sollinger HF Deluca 《Canadian Metallurgical Quarterly》1998,66(7):824-828
BACKGROUND: 1,25-Dihydroxyvitamin D3, the hormonal form of vitamin D, is now believed to play a significant role in the immune responses, both in vitro and in vivo, preventing the development of several autoimmune diseases. These studies suggest that 1,25-dihydroxyvitamin D3 may be effective in prolonging allograph survival. METHODS: To test the hypothesis that 1,25-dihydroxyvitamin D3 would prolong allograft survival, neonatal heart grafts were transplanted to allogeneic recipients receiving either 19-nor-1,25-dihydroxyvitamin D2 (200 ng/day) or 1,25-dihydroxyvitamin D3 (50 ng/mouse/day) orally through the diet. The efficacy of 1,25-dihydroxyvitamin D3 in prolonging graft survival in a vascularized model was determined by heterotopic ACI to Lewis heart transplants. RESULTS: The provision of exogenous 1,25-dihydroxyvitamin D3 or an analog, 19-nor-1,25-dihydroxyvitamin D2, to mice markedly prolonged the survival of neonatal mouse heart allografts. Similar results were obtained with a vascularized heterotopic heart transplant model in rats. Cyclosporine at a maximum 25 mg/kg dose for mice proved less effective than 1,25-dihydroxyvitamin D3. Graft survival in mice differing at class I and class II loci (B10.A(4R) --> C57BL/10) increased from 13.0+/-1.1 days to 51.0+/-5.6 days and was significantly better than cyclosporine monotherapy (33.2+/-3.6). Rat heart survival in a high responder strain combination (ACI --> Lewis) increased from 6.2+/-0.3 to 25.2+/-2.8 days. The increased survival of the transplants brought about with 1,25-dihydroxyvitamin D3 was not accompanied by hypercalcemia in rats. CONCLUSION: These results suggest that 1,25-dihydroxyvitamin D3 can be used as an effective agent in preventing graft rejection. 相似文献
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DJ Kereiakes AM Lincoff DP Miller JE Tcheng CF Cabot KM Anderson HF Weisman RM Califf EJ Topol 《Canadian Metallurgical Quarterly》1998,97(9):857-864
BACKGROUND: Recent studies indicate that eradication of Helicobacter pylori might prevent peptic ulcer formation in patients treated with non-steroidal anti-inflammatory drugs (NSAIDs). On the other hand, gastric adaptation after repeated exposures to aspirin (ASA) is well documented but the influence of H. pylori on this process remains to be elucidated. AIM: To compare gastric damage and adaptation following repeated exposures to ASA in a group of patients with H. pylori infection, before and after eradication of the bacterium, and in H. pylori-negative controls. METHODS: Eight healthy volunteers without H. pylori infection and eight patients with duodenal ulcer (DU) history and H. pylori infection before and after H. pylori eradication were given ASA 2 g/day for a period of 14 days. Mucosal damage was evaluated by endoscopy and histology of biopsy samples. Gastric microbleeding, DNA synthesis in the gastric mucosa and mucosal expression, as well as luminal content of transforming growth factor-alpha (TGFalpha) were determined on days 0, 3, 7 and 14 of the ASA course. RESULTS: In all patients aspirin-induced gastric damage reached a maximum on day 3. In H. pylori-positive patients, this damage was maintained at a similar level up to day 14, whereas in H. pylori-negative controls and H. pylori-eradicated patients this damage significantly lessened on day 14 and was accompanied by elevated DNA synthesis as well as increased mucosal expression and luminal release of TGFalpha. 相似文献
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Although myelin basic protein (MBP)-recognizing T cells are not readily obtained after immunization of BALB/c mice with MBP (reflecting the BALB/c resistance to actively induced experimental autoimmune encephalomyelitis (EAE)), they can be expanded and cloned after several rounds of in vitro culture. The majority of BALB/c-derived clones recognize an epitope defined by MBP peptide 59-76. When transferred to naive BALB/c recipients, these clones cause classical EAE, with characteristic inflammation and demyelination of the central nervous system (CNS). We previously showed that two related clones recognizing a minor epitope, defined by MBP peptide 151-168, cause inflammation and demyelination preferentially of the peripheral nervous system (PNS). Because MBP has alternatively spliced isoforms, residues 151-168 are not present contiguously in all MBP isoforms. In order to determine whether induction of PNS disease is idiosyncratic to these sister clones, or related to their properties of epitope recognition, an independent T-cell line with similar recognition properties was studied. Clone 116F, derived from a BALB/c shiverer mouse, expresses a different T-cell receptor (TCR), with distinct TCR contact residues, but like the previously described T cells, this clone requires residues from both exons 6 and 7 for optimal stimulation. When adoptively transferred to BALB/c recipients, this clone preferentially induces disease of the PNS. A control BALB/c shiverer-derived MBP 59-76-recognizing clone, in contrast, induces CNS disease. These data strongly suggest that the site of disease initiation may correlate with epitope recognition, particularly when alternative isoforms are involved. 相似文献
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SM Haslam GC Coles EA Munn TS Smith HF Smith HR Morris A Dell 《Canadian Metallurgical Quarterly》1996,271(48):30561-30570
Structural studies on the N-linked oligosaccharides of Haemonchus contortus, an economically important nematode that parasitizes domestic ruminants, have revealed core fucosylation of a type not previously observed in any eukaryotic glycoprotein. Mass spectrometric analyses were performed on detergent extracts of homogenized adult H. contortus and on purified H11, a glycoprotein isolated from intestinal brush borders which has been previously shown to be an effective vaccine antigen. The major N-linked glycans identified in the present study have up to three fucose residues attached to their chitobiose cores. The fucoses are found at the 3- and/or 6-positions of the proximal GlcNAc and at the 3-position of the distal GlcNAc. The latter substitution is unique in N-glycans. Most anti-H11 monoclonal antibodies are known to recognize carbohydrate epitopes, and it is possible that the newly discovered multifucosylated core structures are highly immunogenic in this glycoprotein. 相似文献
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