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91.
92.
Yumoto F Nguyen P Sablin EP Baxter JD Webb P Fletterick RJ 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(1):143-148
We report the three-dimensional structure of a β-catenin armadillo repeat in complex with the liver receptor homolog-1 (LRH-1) ligand binding domain at 2.8 Å resolution as the first structure of β-catenin in complex with any nuclear receptor. The surface of β-catenin that binds LRH-1 partly overlaps defined contact sites for peptide segments of β-catenin partners, including T-cell factor-4. The surface of LRH-1 that engages β-catenin is comprised of helices 1, 9, and 10 and is distinct from known interaction surfaces of LRH-1, including corepressor and coactivator binding sites. Targeted mutagenesis of amino acids forming both sides of the LRH-1/β-catenin interface reveals that they are essential for stable interactions between these proteins in solution. The LRH-1 binding site in β-catenin is also required for association with androgen receptor, providing evidence that the observed LRH-1/β-catenin interaction may be prototypic. 相似文献
93.
Protected areas facilitate species' range expansions 总被引:1,自引:0,他引:1
CD Thomas PK Gillingham RB Bradbury DB Roy BJ Anderson JM Baxter NA Bourn HQ Crick RA Findon R Fox JA Hodgson AR Holt MD Morecroft NJ O'Hanlon TH Oliver JW Pearce-Higgins DA Procter JA Thomas KJ Walker CA Walmsley RJ Wilson JK Hill 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(35):14063-14068
The benefits of protected areas (PAs) for biodiversity have been questioned in the context of climate change because PAs are static, whereas the distributions of species are dynamic. Current PAs may, however, continue to be important if they provide suitable locations for species to colonize at their leading-edge range boundaries, thereby enabling spread into new regions. Here, we present an empirical assessment of the role of PAs as targets for colonization during recent range expansions. Records from intensive surveys revealed that seven bird and butterfly species have colonized PAs 4.2 (median) times more frequently than expected from the availability of PAs in the landscapes colonized. Records of an additional 256 invertebrate species with less-intensive surveys supported these findings and showed that 98% of species are disproportionately associated with PAs in newly colonized parts of their ranges. Although colonizing species favor PAs in general, species vary greatly in their reliance on PAs, reflecting differences in the dependence of individual species on particular habitats and other conditions that are available only in PAs. These findings highlight the importance of current PAs for facilitating range expansions and show that a small subset of the landscape receives a high proportion of colonizations by range-expanding species. 相似文献
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Fiona?J?CharlsonEmail author Andrew?E?Moran Greg?Freedman Rosana?E?Norman Nicolas?JC?Stapelberg Amanda?J?Baxter Theo?Vos Harvey?A?Whiteford 《BMC medicine》2013,11(1):250
Background
Cardiovascular disease and mental health both hold enormous public health importance, both ranking highly in results of the recent Global Burden of Disease Study 2010 (GBD 2010). For the first time, the GBD 2010 has systematically and quantitatively assessed major depression as an independent risk factor for the development of ischemic heart disease (IHD) using comparative risk assessment methodology.Methods
A pooled relative risk (RR) was calculated from studies identified through a systematic review with strict inclusion criteria designed to provide evidence of independent risk factor status. Accepted case definitions of depression include diagnosis by a clinician or by non-clinician raters adhering to Diagnostic and Statistical Manual of Mental Disorders (DSM) or International Classification of Diseases (ICD) classifications. We therefore refer to the exposure in this paper as major depression as opposed to the DSM-IV category of major depressive disorder (MDD). The population attributable fraction (PAF) was calculated using the pooled RR estimate. Attributable burden was calculated by multiplying the PAF by the underlying burden of IHD estimated as part of GBD 2010.Results
The pooled relative risk of developing IHD in those with major depression was 1.56 (95% CI 1.30 to 1.87). Globally there were almost 4 million estimated IHD disability-adjusted life years (DALYs), which can be attributed to major depression in 2010; 3.5 million years of life lost and 250,000 years of life lived with a disability. These findings highlight a previously underestimated mortality component of the burden of major depression. As a proportion of overall IHD burden, 2.95% (95% CI 1.48 to 4.46%) of IHD DALYs were estimated to be attributable to MDD in 2010. Eastern Europe and North Africa/Middle East demonstrate the highest proportion with Asia Pacific, high income representing the lowest.Conclusions
The present work comprises the most robust systematic review of its kind to date. The key finding that major depression may be responsible for approximately 3% of global IHD DALYs warrants assessment for depression in patients at high risk of developing IHD or at risk of a repeat IHD event.96.
Wasti SP van Teijlingen E Simkhada P Randall J Baxter S Kirkpatrick P Gc VS 《Tropical medicine & international health : TM & IH》2012,17(1):71-81
Objective To systematically review the literature of factors affecting adherence to Antiretroviral treatment (ART) in Asian developing countries. Methods Database searches in Medline/Ovid, Cochrane library, CINAHL, Scopus and PsychINFO for studies published between 1996 and December 2010. The reference lists of included papers were also checked, with citation searching on key papers. Results A total of 437 studies were identified, and 18 articles met the inclusion criteria and were extracted and critically appraised, representing in 12 quantitative, four qualitative and two mixed‐method studies. Twenty‐two individual themes, including financial difficulties, side effects, access, stigma and discrimination, simply forgetting and being too busy, impeded adherence to ART, and 11 themes, including family support, self‐efficacy and desire to live longer, facilitated adherence. Conclusion Adherence to ART varies between individuals and over time. We need to redress impeding factors while promoting factors that reinforce adherence through financial support, better accessible points for medicine refills, consulting doctors for help with side effects, social support and trusting relationships with care providers. 相似文献
97.
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99.
M. L. Melcher C. D. Blosser L. A. Baxter‐Lowe F. L. Delmonico S. E. Gentry R. Leishman G. A. Knoll M. S. Leffell A. B. Leichtman D. A. Mast P. W. Nickerson E. F. Reed M. A. Rees J. R. Rodrigue D. L. Segev D. Serur S. G. Tullius E. Y. Zavala S. Feng 《American journal of transplantation》2013,13(4):851-860
While kidney paired donation (KPD) enables the utilization of living donor kidneys from healthy and willing donors incompatible with their intended recipients, the strategy poses complex challenges that have limited its adoption in United States and Canada. A consensus conference was convened March 29–30, 2012 to address the dynamic challenges and complexities of KPD that inhibit optimal implementation. Stakeholders considered donor evaluation and care, histocompatibility testing, allocation algorithms, financing, geographic challenges and implementation strategies with the goal to safely maximize KPD at every transplant center. Best practices, knowledge gaps and research goals were identified and summarized in this document. 相似文献
100.
This study reports on the effects of x-ray CT dose in CT imaged normoxic polyacrylamide (nPAG) gel dosimeters. The investigation is partitioned into three sections. First, the CT dose absorbed in nPAG is quantified under a range of typical gel CT imaging protocols. It is found that the maximum absorbed CT dose occurs for volumetric imaging and is in the range of 4.6 +/- 0.2 cGy/image. This does scales linearly with image averaging. Second, using Raman spectroscopy, the response of nPAG to CT imaging photon energies (i.e., 120-140 kVp) is established and compared to the well known dose response of nPAG exposed to 6 MV photons. It is found that nPAG exhibits a weaker response (per unit dose) to 140-kVp incident photons as compared to 6 MV incident photons (slopes m6 mv = -0.0374 +/- 0.0006 Gy(-1) and m140 kVp = -0.016 +/- 0.001 Gy(-1)). Finally, using the above data, an induced change in CT number (deltaN(CT)) is calculated for nPAG imaged using a range of gel imaging protocols. It is found that under typical imaging protocols (120-140 kVp, 200 mAs, approximately 16-32 image averages) a deltaN(CT) < 0.2 H is induced in active nPAG dosimeters. This deltaN(CT) is below the current limit of detectability of CT nPAG polymer gel dosimetry. Under expanded imaging protocols (e.g., very high number of image averages) an induced deltaN(CT) of approximately 0.5 H is possible. In these situations the additional polymerization occurring in nPAG due to the imaging process may need to be accounted for. 相似文献