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JN Matthiessen 《Australian Journal of Entomology》1999,38(4):348-353
In field and laboratory studies, mortality of African black beetle, Heteronychus arator, in the winter-rainfall, Mediterranean-type climate region of south-western Australia was higher in the late immature stages during summer than in the early immature stages that occur during spring, a contrast to summer-rainfall climatic regions. Greatest mortality occurred around the pupal stage in contrasting soil types, despite drying differences in summer and supplementary watering in some plots. Sampling of natural populations confirmed experimental results that mortality in late immature stages is the major factor limiting H. arator populations under a Mediterranean-type climate. Inter-generation increase in H. arator abundance was uncommon, explaining the consistent abundance typically observed between years in south-western Australia. Random dispersal of newly emerged adults in autumn was inferred to restore uniformity in adult abundance between areas of varying favourability for immature survival. 相似文献
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The application of the AMB protective group in the solid-phase synthesis of methylphosphonate DNA analogues. 总被引:2,自引:1,他引:1 下载免费PDF全文
W H Kuijpers E Kuyl-Yeheskiely J H van Boom C A van Boeckel 《Nucleic acids research》1993,21(15):3493-3500
Partially methylphosphonate-modified oligodeoxynucleotides were synthesized on solid-phase by employing the easily removable 2-(acetoxymethyl)benzoyl (AMB) group as base-protecting group. Although a rapid AMB deprotection can be accomplished in methanolic potassium carbonate, the lability of the methylphosphonate linkage towards potassium carbonate/methanol excludes the use of this deprotection reagent. Thus, saturated ammonia solution in methanol was investigated as an alternative reagent for AMB removal. It is demonstrated that the combination of the AMB protective group and ammonia/methanol as deprotection reagent significantly improves the synthesis of methylphosphonate-modified DNA fragments. A mild overnight treatment at room temperature is sufficient for complete removal of the AMB group, whereas deprotection of conventionally protected oligonucleotides requires much longer exposure to basic conditions at elevated temperatures. 相似文献
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J B Rewinkel H Lucas M J Smit A B Noach T G van Dinther A M Rood A J Jenneboer C A van Boeckel 《Bioorganic & medicinal chemistry letters》1999,9(19):2837-2842
Replacement of the highly basic benzamidine moiety with moderate basic amino-bicycloaryl moieties in a series of thrombin inhibitors related to NAPAMP provided potent enzyme inhibition and significant improvements in membrane transport and oral bioavailability. 相似文献
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Mapping the Global Distribution of Livestock 总被引:2,自引:0,他引:2
Timothy P. Robinson G. R. William Wint Giulia Conchedda Thomas P. Van Boeckel Valentina Ercoli Elisa Palamara Giuseppina Cinardi Laura D'Aietti Simon I. Hay Marius Gilbert 《PloS one》2014,9(5)
Livestock contributes directly to the livelihoods and food security of almost a billion people and affects the diet and health of many more. With estimated standing populations of 1.43 billion cattle, 1.87 billion sheep and goats, 0.98 billion pigs, and 19.60 billion chickens, reliable and accessible information on the distribution and abundance of livestock is needed for a many reasons. These include analyses of the social and economic aspects of the livestock sector; the environmental impacts of livestock such as the production and management of waste, greenhouse gas emissions and livestock-related land-use change; and large-scale public health and epidemiological investigations. The Gridded Livestock of the World (GLW) database, produced in 2007, provided modelled livestock densities of the world, adjusted to match official (FAOSTAT) national estimates for the reference year 2005, at a spatial resolution of 3 minutes of arc (about 5×5 km at the equator). Recent methodological improvements have significantly enhanced these distributions: more up-to date and detailed sub-national livestock statistics have been collected; a new, higher resolution set of predictor variables is used; and the analytical procedure has been revised and extended to include a more systematic assessment of model accuracy and the representation of uncertainties associated with the predictions. This paper describes the current approach in detail and presents new global distribution maps at 1 km resolution for cattle, pigs and chickens, and a partial distribution map for ducks. These digital layers are made publically available via the Livestock Geo-Wiki (http://www.livestock.geo-wiki.org), as will be the maps of other livestock types as they are produced. 相似文献
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BRCA1 C-terminal (BRCT) domains are integral signaling modules in the DNA damage response (DDR). Aside from their established roles as phospho-peptide binding modules, BRCT domains have been implicated in phosphorylation-independent protein interactions, DNA binding and poly(ADP-ribose) (PAR) binding. These numerous functions can be attributed to the diversity in BRCT domain structure and architecture, where domains can exist as isolated single domains or assemble into higher order homo- or hetero-domain complexes. In this review, we incorporate recent structural and biochemical studies to demonstrate how structural features allow single and tandem BRCT domains to attain a high degree of functional diversity.Key words: BRCT domain, DNA repair, phosphorylation, phospho-peptide interaction, protein interaction, DNA binding, DNA damage response 相似文献
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Petra G.A. van Boeckel Hendriek C. Boshuizen Peter D. Siersema Alina Vrieling Anton E. Kunst Weimin Ye Malin Sund Dominique S. Michaud Valentina Gallo Elizabeth A. Spencer Antonia Trichopoulou Vasiliki Benetou Philippos Orfanos Lluis Cirera Eric J. Duell Sabine Rohrmann Silke Hemann Giovanni Masala Jonas Manjer Amalia Mattiello B. Bueno-de-Mesquita 《Cancer epidemiology》2010,34(6):696-701
Introduction: Until now, studies examining the relationship between socioeconomic status and pancreatic cancer incidence have been inconclusive. Aim: To prospectively investigate to what extent pancreatic cancer incidence varies according to educational level within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Methods: In the EPIC study, socioeconomic status at baseline was measured using the highest level of education attained. Hazard ratios by educational level and a summary index, the relative indices of inequality (RII), were estimated using Cox regression models stratified by age, gender, and center and adjusted for known risk factors. In addition, we conducted separate analyses by age, gender and geographical region. Results: Within the source population of 407, 944 individuals at baseline, 490 first incident primary pancreatic adenocarcinoma cases were identified in 9 European countries. The crude difference in risk of pancreatic cancer according to level of education was small and not statistically significant (RII = 1.14, 95% CI 0.80–1.62). Adjustment for known risk factors reduced the inequality estimates to only a small extent. In addition, no statistically significant associations were observed for age groups (adjusted RII≤ 60 years = 0.85, 95% CI 0.44–1.64, adjusted RII>60 years = 1.18, 95% CI 0.73–1.90), gender (adjusted RIImale = 1.20, 95% CI 0.68–2.10, adjusted RIIfemale = 0.96, 95% CI 0.56–1.62) or geographical region (adjusted RIINorthern Europe = 1.14, 95% CI 0.81–1.61, adjusted RIIMiddle Europe = 1.72, 95% CI 0.93–3.19, adjusted RIISouthern Europe = 0.75, 95% CI 0.32–1.80). Conclusion: Despite large educational inequalities in many risk factors within the EPIC study, we found no evidence for an association between educational level and the risk of developing pancreatic cancer in this European cohort. 相似文献
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R C Buijsman J E Basten C M Dreef-Tromp G A van der Marel C A van Boeckel J H van Boom 《Bioorganic & medicinal chemistry》1999,7(9):1881-1890
The synthesis of three heparin analogues (i.e. compounds VI-VIII) having perphosphorylated thrombin binding domains (TBDs) is reported. These compounds were tested in vitro for their antithrombin III (ATIII)-mediated anti-Xa and antithrombin activities. Conjugates VI and VIII show a remarkable increase in antithrombin activity compared to the structurally related conjugates with persulfated TBDs (i.e. compounds IV and V), whereas compound VII displays a diminished activity. 相似文献
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Marie-José C. van Lierop Wynand Alkema Anke J. Laskewitz Rein Dijkema Hans M. van der Maaden Martin J. Smit Ralf Plate Paolo G. M. Conti Christan G. J. M. Jans C. Marco Timmers Constant A. A. van Boeckel Scott J. Lusher Ross McGuire Rene C. van Schaik Jacob de Vlieg Ruben L. Smeets Claudia L. Hofstra Annemieke M. H. Boots Marcel van Duin Benno A. Ingelse Willem G. E. J. Schoonen Aldo Grefhorst Theo H. van Dijk Folkert Kuipers Wim H. A. Dokter 《PloS one》2012,7(11)
Glucocorticoids (GCs) such as prednisolone are potent immunosuppressive drugs but suffer from severe adverse effects, including the induction of insulin resistance. Therefore, development of so-called Selective Glucocorticoid Receptor Modulators (SGRM) is highly desirable. Here we describe a non-steroidal Glucocorticoid Receptor (GR)-selective compound (Org 214007-0) with a binding affinity to GR similar to that of prednisolone. Structural modelling of the GR-Org 214007-0 binding site shows disturbance of the loop between helix 11 and helix 12 of GR, confirmed by partial recruitment of the TIF2-3 peptide. Using various cell lines and primary human cells, we show here that Org 214007-0 acts as a partial GC agonist, since it repressed inflammatory genes and was less effective in induction of metabolic genes. More importantly, in vivo studies in mice indicated that Org 214007-0 retained full efficacy in acute inflammation models as well as in a chronic collagen-induced arthritis (CIA) model. Gene expression profiling of muscle tissue derived from arthritic mice showed a partial activity of Org 214007-0 at an equi-efficacious dosage of prednisolone, with an increased ratio in repression versus induction of genes. Finally, in mice Org 214007-0 did not induce elevated fasting glucose nor the shift in glucose/glycogen balance in the liver seen with an equi-efficacious dose of prednisolone. All together, our data demonstrate that Org 214007-0 is a novel SGRMs with an improved therapeutic index compared to prednisolone. This class of SGRMs can contribute to effective anti-inflammatory therapy with a lower risk for metabolic side effects. 相似文献
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