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排序方式: 共有261条查询结果,搜索用时 15 毫秒
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Carlton JM Angiuoli SV Suh BB Kooij TW Pertea M Silva JC Ermolaeva MD Allen JE Selengut JD Koo HL Peterson JD Pop M Kosack DS Shumway MF Bidwell SL Shallom SJ van Aken SE Riedmuller SB Feldblyum TV Cho JK Quackenbush J Sedegah M Shoaibi A Cummings LM Florens L Yates JR Raine JD Sinden RE Harris MA Cunningham DA Preiser PR Bergman LW Vaidya AB van Lin LH Janse CJ Waters AP Smith HO White OR Salzberg SL Venter JC Fraser CM Hoffman SL Gardner MJ Carucci DJ 《Nature》2002,419(6906):512-519
Species of malaria parasite that infect rodents have long been used as models for malaria disease research. Here we report the whole-genome shotgun sequence of one species, Plasmodium yoelii yoelii, and comparative studies with the genome of the human malaria parasite Plasmodium falciparum clone 3D7. A synteny map of 2,212 P. y. yoelii contiguous DNA sequences (contigs) aligned to 14 P. falciparum chromosomes reveals marked conservation of gene synteny within the body of each chromosome. Of about 5,300 P. falciparum genes, more than 3,300 P. y. yoelii orthologues of predominantly metabolic function were identified. Over 800 copies of a variant antigen gene located in subtelomeric regions were found. This is the first genome sequence of a model eukaryotic parasite, and it provides insight into the use of such systems in the modelling of Plasmodium biology and disease. 相似文献
84.
Microsomal cytochrome P450 and eicosanoid metabolism 总被引:1,自引:0,他引:1
The demonstration of a role for microsomal P450 in the metabolism of endogenous pools of arachidonic acid established this
enzyme system as a member of the arachidonic acid cascade and characterized a new an important metabolic function for this
enzyme system. Studies from several laboratories documenting the powerful biological activities of the P450-derived eicosanoids
have suggested important roles for the P450 arachidonic acid monooxygenase in renal and vascular physiology, and in the pathophysiology
of experimental hypertension. These studies provide significant evidence to indicate that in addition to its recognized traditional
toxicological and pharmacological roles, microsomal P450s also play important physiological roles in the control of tissue
and body homeostasis. 相似文献
85.
Quantum annealing with manufactured spins 总被引:1,自引:0,他引:1
Johnson MW Amin MH Gildert S Lanting T Hamze F Dickson N Harris R Berkley AJ Johansson J Bunyk P Chapple EM Enderud C Hilton JP Karimi K Ladizinsky E Ladizinsky N Oh T Perminov I Rich C Thom MC Tolkacheva E Truncik CJ Uchaikin S Wang J Wilson B Rose G 《Nature》2011,473(7346):194-198
Many interesting but practically intractable problems can be reduced to that of finding the ground state of a system of interacting spins; however, finding such a ground state remains computationally difficult. It is believed that the ground state of some naturally occurring spin systems can be effectively attained through a process called quantum annealing. If it could be harnessed, quantum annealing might improve on known methods for solving certain types of problem. However, physical investigation of quantum annealing has been largely confined to microscopic spins in condensed-matter systems. Here we use quantum annealing to find the ground state of an artificial Ising spin system comprising an array of eight superconducting flux quantum bits with programmable spin-spin couplings. We observe a clear signature of quantum annealing, distinguishable from classical thermal annealing through the temperature dependence of the time at which the system dynamics freezes. Our implementation can be configured in situ to realize a wide variety of different spin networks, each of which can be monitored as it moves towards a low-energy configuration. This programmable artificial spin network bridges the gap between the theoretical study of ideal isolated spin networks and the experimental investigation of bulk magnetic samples. Moreover, with an increased number of spins, such a system may provide a practical physical means to implement a quantum algorithm, possibly allowing more-effective approaches to solving certain classes of hard combinatorial optimization problems. 相似文献
86.
P. S. Bhathal S. L. Ho M. P. Hegarty Roger L. N. Harris 《Cellular and molecular life sciences : CMLS》1984,40(8):894-896
Summary Chronic active hepatitis was selectively induced in mice by the feeding of a diet containing 3-hydroxy-4-pyrone (0.5% by weight) for periods of 6 weeks and longer. This model should be of particular value in elucidating the pathogenesis of drug-induced forms of chronic active hepatitis. Maltol (3-hydroxy-2-methyl-4-pyrone) did not produce any liver lesion.Acknowledgment. This research was supported in part by a grant from the Sir A.E. Rowden White Bequest to the Department of Pathology, University of Melbourne.To whom correspondance and requests for reprints should be addressed. 相似文献
87.
S B England L V Nicholson M A Johnson S M Forrest D R Love E E Zubrzycka-Gaarn D E Bulman J B Harris K E Davies 《Nature》1990,343(6254):180-182
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K. Prabhakaran E.B. Harris W.F. Kirchheimer 《Cellular and molecular life sciences : CMLS》1980,36(12):1350-1351
Summary The antileprosy drug dapsone is unable to penetrate intactMycobacterium leprae in vitro, as determined by its effect on o-diphenoloxidase in the bacilli. When combined with the peptide polylysine, the sulfone drug passes through the bacterial cell membranes, and penetrates the enzyme protein, resulting in a 100% inhibition of its activity. 相似文献
90.