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21.
Leigh EG 《Science (New York, N.Y.)》1989,246(4931):828-829
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Kaufmann KJ Dutton PL Netzel TL Leigh JS Rentzepis PM 《Science (New York, N.Y.)》1975,188(4195):1301-1304
A transient absorption spectrum has been measured in Rhodopseudomonas spheroides R26 reaction centers. Its salient features indicate that both the bacteriopheophytin and bacteriochlorophyll chromophores play a role in the excited state. Decay of this state yields a rise time for oxidation of the reaction center complex of about 150 picoseconds. 相似文献
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Wenger OS Leigh BS Villahermosa RM Gray HB Winkler JR 《Science (New York, N.Y.)》2005,307(5706):99-102
Reaction rates extracted from measurements of donor luminescence quenching by randomly dispersed electron acceptors reveal an exponential decay constant of 1.23 per angstrom for electron tunneling through a frozen toluene glass (with a barrier to tunneling of 1.4 electron volts). The decay constant is 1.62 per angstrom (the barrier, 2.6 electron volts) in a frozen 2-methyl-tetrahydrofuran glass. Comparison to decay constants for tunneling across covalently linked xylyl (0.76 per angstrom) and alkyl (1.0 per angstrom) bridges leads to the conclusion that tunneling between solvent molecules separated by approximately 2 angstroms (van der Waals contact) is 20 to 50 times slower than tunneling through a comparable length of a covalently bonded bridge. Our results provide experimental confirmation that covalently bonded pathways can facilitate electron flow through folded polypeptide structures. 相似文献
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Vermetten E Bremner JD Skelton L Spiegel D 《Science (New York, N.Y.)》2007,315(5809):184-7; author reply 184-7
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Sanfey AG Rilling JK Aronson JA Nystrom LE Cohen JD 《Science (New York, N.Y.)》2003,300(5626):1755-1758
The nascent field of neuroeconomics seeks to ground economic decision making in the biological substrate of the brain. We used functional magnetic resonance imaging of Ultimatum Game players to investigate neural substrates of cognitive and emotional processes involved in economic decision-making. In this game, two players split a sum of money;one player proposes a division and the other can accept or reject this. We scanned players as they responded to fair and unfair proposals. Unfair offers elicited activity in brain areas related to both emotion (anterior insula) and cognition (dorsolateral prefrontal cortex). Further, significantly heightened activity in anterior insula for rejected unfair offers suggests an important role for emotions in decision-making. 相似文献
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Sreedharan J Blair IP Tripathi VB Hu X Vance C Rogelj B Ackerley S Durnall JC Williams KL Buratti E Baralle F de Belleroche J Mitchell JD Leigh PN Al-Chalabi A Miller CC Nicholson G Shaw CE 《Science (New York, N.Y.)》2008,319(5870):1668-1672
Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disorder characterized pathologically by ubiquitinated TAR DNA binding protein (TDP-43) inclusions. The function of TDP-43 in the nervous system is uncertain, and a mechanistic role in neurodegeneration remains speculative. We identified neighboring mutations in a highly conserved region of TARDBP in sporadic and familial ALS cases. TARDBPM337V segregated with disease within one kindred and a genome-wide scan confirmed that linkage was restricted to chromosome 1p36, which contains the TARDBP locus. Mutant forms of TDP-43 fragmented in vitro more readily than wild type and, in vivo, caused neural apoptosis and developmental delay in the chick embryo. Our evidence suggests a pathophysiological link between TDP-43 and ALS. 相似文献