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951.
Canada generates approximately 1.45 x 10(8)t of residual biomass per year, containing an estimated energy value of 2.28 x 10(9)GJ, which is equivalent to about 22% of Canada's current annual energy use. Anaerobic digestion of these biomass residues using conventional technologies could generate 1.14 x 10(10)m(3)/year of CH(4) with a heating value of 4.56 x 10(8)GJ. Conversion of these residues using emerging technologies that favor the synthesis of H(2) and represses the synthesis of CH(4) could generate 1.47 x 10(10)m(3)/year renewable H(2), with a heating value of 1.89 x 10(8)GJ. While CH(4)-production results in a larger amount of energy recovery, generating H(2) from waste biomass is a renewable alternative that could fuel the hydrogen economy. Additional research to further both the technical and commercial development of microbial bio-energy from biomass is warranted. 相似文献
952.
Van Camp JA Hu LY Kostlan C Lefker B Li J Mitchell L Wang Z Yue WS Carroll M Dettling D Du D Pocalyko D Wade K 《Bioorganic & medicinal chemistry letters》2007,17(20):5529-5532
A series of substituted 4-aryl-2-trifluoromethylbenzonitrile analogs were evaluated in the human androgen receptor binding and cellular functional assays. Analogs with sufficient in vitro binding and cellular potency (IC(50)<200 nM) were tested in the progesterone receptor binding assay for selectivity and in the Golden Syrian hamster ear model for in vivo efficacy. Within the series, compound 4 e was identified to be the most active analog in vivo (wax ester inhibition=86%). 相似文献
953.
Sulsky R Magnin DR Huang Y Simpkins L Taunk P Patel M Zhu Y Stouch TR Bassolino-Klimas D Parker R Harrity T Stoffel R Taylor DS Lavoie TB Kish K Jacobson BL Sheriff S Adam LP Ewing WR Robl JA 《Bioorganic & medicinal chemistry letters》2007,17(12):3511-3515
Herein we report the first disclosure of biphenyl azoles that are nanomolar binders of adipocyte fatty acid binding protein (aFABP or aP2) with up to thousand-fold selectivity against muscle fatty acid binding protein and epidermal fatty acid binding protein. In addition a new radio-ligand to determine binding against the three fatty acid binding proteins was also synthesized. 相似文献
954.
Ubiquitin-independent degradation of cell-cycle inhibitors by the REGgamma proteasome 总被引:5,自引:0,他引:5
The cell-cycle regulator p21(Cip1) is degraded by proteasomes independently of ubiquitination. We now show that degradation of p21 in vivo does not require the 19S proteasome lid, which contains the ubiquitin-binding subunit. Instead, the major proteasomal pathway for p21 degradation involves an alternative proteasome lid, the REGgamma complex. REGgamma binds to p21 in vivo, and deletion of p21's REGgamma-binding site greatly extends its half-life. Knockdown of REGgamma by RNA interference stabilizes p21, p21 has a significantly extended half-life in REGgamma(-/-) murine embryonic fibroblasts, and the p21 abundance is elevated in REGgamma(-/-) mice. The role of REGgamma in cell-cycle regulation may extend beyond p21 regulation, because p16(INK4A) and p19(Arf) also bind to REGgamma and are stabilized in REGgamma-deficient cells. 相似文献
955.
Classification and prediction of clinical Alzheimer's diagnosis based on plasma signaling proteins 总被引:10,自引:0,他引:10
Ray S Britschgi M Herbert C Takeda-Uchimura Y Boxer A Blennow K Friedman LF Galasko DR Jutel M Karydas A Kaye JA Leszek J Miller BL Minthon L Quinn JF Rabinovici GD Robinson WH Sabbagh MN So YT Sparks DL Tabaton M Tinklenberg J Yesavage JA Tibshirani R Wyss-Coray T 《Nature medicine》2007,13(11):1359-1362
A molecular test for Alzheimer's disease could lead to better treatment and therapies. We found 18 signaling proteins in blood plasma that can be used to classify blinded samples from Alzheimer's and control subjects with close to 90% accuracy and to identify patients who had mild cognitive impairment that progressed to Alzheimer's disease 2-6 years later. Biological analysis of the 18 proteins points to systemic dysregulation of hematopoiesis, immune responses, apoptosis and neuronal support in presymptomatic Alzheimer's disease. 相似文献
956.
Antibodies are used extensively in diagnostics and as therapeutic agents. Achieving high-affinity binding is important for expanding detection limits, extending dissociation half-times, decreasing drug dosages and increasing drug efficacy. However, antibody-affinity maturation in vivo often fails to produce antibody drugs of the targeted potency, making further affinity maturation in vitro by directed evolution or computational design necessary. Here we present an iterative computational design procedure that focuses on electrostatic binding contributions and single mutants. By combining multiple designed mutations, a tenfold affinity improvement to 52 pM was engineered into the anti-epidermal growth factor receptor drug cetuximab (Erbitux), and a 140-fold improvement in affinity to 30 pM was obtained for the anti-lysozyme model antibody D44.1. The generality of the methods was further demonstrated through identification of known affinity-enhancing mutations in the therapeutic antibody bevacizumab (Avastin) and the model anti-fluorescein antibody 4-4-20. These results demonstrate computational capabilities for enhancing and accelerating the development of protein reagents and therapeutics. 相似文献
957.
We compared patterns of mitochondrial restriction fragment length polymorphism (RFLP) diversity with patterns of nuclear RFLP diversity to investigate the effects of selection, gene flow, and sexual reproduction on the population genetic structure and evolutionary history of the wheat pathogen Phaeosphaeria nodorum. A total of 315 fungal isolates from Texas, Oregon, and Switzerland were analyzed using seven nuclear RFLP probes that hybridized to discrete loci and purified mitochondrial DNA that hybridized to the entire mtDNA genome. Forty-two different mitochondrial haplotypes and 298 different nuclear haplotypes were detected. The two most frequent mtDNA haplotypes were present in every population and represented 32% of all isolates. High levels of gene flow, low levels of population subdivision, no evidence for either host specificity or cyto-nuclear disequilibrium were inferred from the analysis of both genomes. The concordance in estimates of these population genetic parameters from both genomes suggests that the two genomes experienced similar degrees of migration, genetic drift and selection. 相似文献
958.
959.
Bruce Kapferer 《The Australian journal of anthropology》2007,18(1):72-94
The knowledge practices of social and cultural anthropology can be conceived as undergoing constant methodological reconsideration or reformulation as a consequence of internal critique and of institutional change effected in the larger educational and political environment. Neo‐liberal shifts affecting the institutional context may have influenced a deepening of the crisis in anthropology where the nature of its project has become less certain or has threatened a reconfiguration of such proportion that anthropology may be losing sight of its direction. This essay explores some of the Enlightenment roots of social and cultural anthropology. It is presented as very much an idea that embodies and reflects what Adorno and Horkheimer discussed as the dialectic of Enlightenment. The argument presented is less pessimistic claiming that the distinction of anthropology is in its pursuit of Enlightenment ideals that it has maintained and rehoned as a consequence of its own routine internal critique. The vital implication of the discussion is that anthropology is in a situation of serious threat in largely a post‐Enlightenment world. In such a context, the methodological ideals that emerged as integral to the spirit of anthropology are well worth maintaining rather than abandoning. The ideals that are addressed are conceived to be integral to the importance of anthropology as critique and as a knowledge practice capable of sustaining a profound contribution to the understanding of the potential that is human being. 相似文献
960.