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141.
Anand K Ziebuhr J Wadhwani P Mesters JR Hilgenfeld R 《Science (New York, N.Y.)》2003,300(5626):1763-1767
A novel coronavirus has been identified as the causative agent of severe acute respiratory syndrome (SARS). The viral main proteinase (Mpro, also called 3CLpro), which controls the activities of the coronavirus replication complex, is an attractive target for therapy. We determined crystal structures for human coronavirus (strain 229E) Mpro and for an inhibitor complex of porcine coronavirus [transmissible gastroenteritis virus (TGEV)] Mpro, and we constructed a homology model for SARS coronavirus (SARS-CoV) Mpro. The structures reveal a remarkable degree of conservation of the substrate-binding sites, which is further supported by recombinant SARS-CoV Mpro-mediated cleavage of a TGEV Mpro substrate. Molecular modeling suggests that available rhinovirus 3Cpro inhibitors may be modified to make them useful for treating SARS. 相似文献
142.
Bonifati V Rizzu P van Baren MJ Schaap O Breedveld GJ Krieger E Dekker MC Squitieri F Ibanez P Joosse M van Dongen JW Vanacore N van Swieten JC Brice A Meco G van Duijn CM Oostra BA Heutink P 《Science (New York, N.Y.)》2003,299(5604):256-259
The DJ-1 gene encodes a ubiquitous, highly conserved protein. Here, we show that DJ-1 mutations are associated with PARK7, a monogenic form of human parkinsonism. The function of the DJ-1 protein remains unknown, but evidence suggests its involvement in the oxidative stress response. Our findings indicate that loss of DJ-1 function leads to neurodegeneration. Elucidating the physiological role of DJ-1 protein may promote understanding of the mechanisms of brain neuronal maintenance and pathogenesis of Parkinson's disease. 相似文献
143.
Karoline D’Haene Annemie Van den Bossche Jeroen Vandenbruwane Stefaan De Neve Donald Gabriels Georges Hofman 《Biology and Fertility of Soils》2008,45(2):213-217
The effect of reduced tillage (RT) on nitrous oxide (N2O) emissions of soils from fields with root crops under a temperate climate was studied. Three silt loam fields under RT agriculture
were compared with their respective conventional tillage (CT) field with comparable crop rotation and manure application.
Undisturbed soil samples taken in September 2005 and February 2006 were incubated under laboratory conditions for 10 days.
The N2O emission of soils taken in September 2005 varied from 50 to 1,095 μg N kg−1 dry soil. The N2O emissions of soils from the RT fields taken in September 2005 were statistically (P < 0.05) higher or comparable than the N2O emissions from their respective CT soil. The N2O emission of soils taken in February 2006 varied from 0 to 233 μg N kg−1 dry soil. The N2O emissions of soils from the RT fields taken in February 2006 tended to be higher than the N2O emissions from their respective CT soil. A positive and significant Pearson correlation of the N2O–N emissions with nitrate nitrogen (NO3
−–N) content in the soil was found (P < 0.01). Leaving the straw on the field, a typical feature of RT, decreased NO3
−–N content of the soil and reduced N2O emissions from RT soils. 相似文献
144.
Since the Green Revolution cropping systems have been progressively homogenized and intensified with increasing rates of inputs such as fertilizers,pesticides and water. This has resulted in higher crop productivity but also a high environmental burden due to increased pollution and water depletion. To identify opportunities for increasing the productivity and reducing the environmental impact of cropping systems, it is crucial to assess the associated trade-offs. The paper presents a model-base... 相似文献