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排序方式: 共有211条查询结果,搜索用时 250 毫秒
81.
Carlton JM Adams JH Silva JC Bidwell SL Lorenzi H Caler E Crabtree J Angiuoli SV Merino EF Amedeo P Cheng Q Coulson RM Crabb BS Del Portillo HA Essien K Feldblyum TV Fernandez-Becerra C Gilson PR Gueye AH Guo X Kang'a S Kooij TW Korsinczky M Meyer EV Nene V Paulsen I White O Ralph SA Ren Q Sargeant TJ Salzberg SL Stoeckert CJ Sullivan SA Yamamoto MM Hoffman SL Wortman JR Gardner MJ Galinski MR Barnwell JW Fraser-Liggett CM 《Nature》2008,455(7214):757-763
The human malaria parasite Plasmodium vivax is responsible for 25-40% of the approximately 515 million annual cases of malaria worldwide. Although seldom fatal, the parasite elicits severe and incapacitating clinical symptoms and often causes relapses months after a primary infection has cleared. Despite its importance as a major human pathogen, P. vivax is little studied because it cannot be propagated continuously in the laboratory except in non-human primates. We sequenced the genome of P. vivax to shed light on its distinctive biological features, and as a means to drive development of new drugs and vaccines. Here we describe the synteny and isochore structure of P. vivax chromosomes, and show that the parasite resembles other malaria parasites in gene content and metabolic potential, but possesses novel gene families and potential alternative invasion pathways not recognized previously. Completion of the P. vivax genome provides the scientific community with a valuable resource that can be used to advance investigation into this neglected species. 相似文献
82.
Quantum control of individual spins in condensed-matter devices is an emerging field with a wide range of applications, from nanospintronics to quantum computing. The electron, possessing spin and orbital degrees of freedom, is conventionally used as the carrier of quantum information in proposed devices. However, electrons couple strongly to the environment, and so have very short relaxation and coherence times. It is therefore extremely difficult to achieve quantum coherence and stable entanglement of electron spins. Alternative concepts propose nuclear spins as the building blocks for quantum computing, because such spins are extremely well isolated from the environment and less prone to decoherence. However, weak coupling comes at a price: it remains challenging to address and manipulate individual nuclear spins. Here we show that the nuclear spin of an individual metal atom embedded in a single-molecule magnet can be read out electronically. The observed long lifetimes (tens of seconds) and relaxation characteristics of nuclear spin at the single-atom scale open the way to a completely new world of devices in which quantum logic may be implemented. 相似文献
83.
Mario Bunge 《Foundations of Science》2017,22(3):455-469
Original research is of course what scientists are expected to do. Therefore the research project is in many ways the unit of science in the making: it is the center of the professional life of the individual scientist and his coworkers. It is also the means towards the culmination of their specific activities: the original publication they hope to contribute to the scientific literature. The scientific project should therefore be of central interest to all the students of science, particularly the philosophers and sociologists of science. We shall focus on the preliminary evaluation of research projects—the specific task of referees—and will emphasize the problem of their scientificity—the chief concern of scientific gatekeepers. In the past such an examination aimed only at protecting the taxpayer from swindlers and incompetent amateurs, such as the inventors of continuous motion artifacts. In recent times a similar issue has resurfaced with regard to some of the most prestigious and most handsomely funded projects, namely work on string theory and many-worlds cosmology. Indeed, some of their faithful have claimed that these theories are so elegant, and so full of high-grade mathematics, that they should be exempted from empirical tests. This claim provoked the spirited rebuttal of the well-known cosmologists Ellis and Silk (Nature 516:321–323, 2014), which the present paper is intended to reinforce. Indeed, we shall try to show why empirical testability is necessary though insufficient for a piece of work to qualify as scientific. Finally, the present paper may also be regarded as an indirect contribution to the current debate over the reliability of quantitative indicators of scientific worth, such as the h-index of scientific productivity (e.g., Wilsdon in Nature 523:129, 2015). But we shall touch only tangentially on the sociological, political, and economics of research teams: our focus will be the acquisition of new scientific knowledge. 相似文献
84.
Wang K Diskin SJ Zhang H Attiyeh EF Winter C Hou C Schnepp RW Diamond M Bosse K Mayes PA Glessner J Kim C Frackelton E Garris M Wang Q Glaberson W Chiavacci R Nguyen L Jagannathan J Saeki N Sasaki H Grant SF Iolascon A Mosse YP Cole KA Li H Devoto M McGrady PW London WB Capasso M Rahman N Hakonarson H Maris JM 《Nature》2011,469(7329):216-220
85.
The prolyl isomerase Pin1 reveals a mechanism to control p53 functions after genotoxic insults 总被引:5,自引:0,他引:5
Zacchi P Gostissa M Uchida T Salvagno C Avolio F Volinia S Ronai Z Blandino G Schneider C Del Sal G 《Nature》2002,419(6909):853-857
86.
87.
88.
C. Di Ilio P. Sacchetta G. Del Boccio A. Muccini G. Polidoro 《Cellular and molecular life sciences : CMLS》1985,41(1):66-67
Summary The levels of GSH-related enzyme activities during pregnancy were determined. A significant increase in Selenium-dependent GSH peroxidase and GSH S-transferase E activity was observed. A concomitant increase in -glutamylcysteine synthetase was measured, which indicated an increased ability to synthesize the tripeptide. 相似文献
89.
90.
Marini I Moschini R Del Corso A Mura U 《Cellular and molecular life sciences : CMLS》2005,62(24):3092-3099
The chaperone behaviour of bovine serum albumin was compared with that of α-crystallin. The chaperone activity was assessed
by measuring: (i) the ability to antagonize protein aggregation induced by heat; (ii) the capability to protect the activity
of thermally stressed enzymes and (iii) the effectiveness in assisting the functional recovery of chemically denatured sorbitol
dehydrogenase. Despite the lack of structural analogies, both proteins show several functional similarities in preventing
inactivation of thermally stressed enzymes and in reactivating chemically denatured sorbitol dehydrogenase. As with α-crystallin,
the chaperone action of bovine serum albumin appears to be ATP independent. Bovine serum albumin appears significantly less
effective than α-crystallin only in preventing thermally induced protein aggregation. A possible relationship between chaperone
function and structural organization is proposed. Together, our results indicate that bovine serum albumin acts as a molecular
chaperone and that, for its particular distribution, can be included in the extracellular chaperone family.
Received 29 August 2005; received after revision 23 September 2005; accepted 12 October 2005 相似文献