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排序方式: 共有623条查询结果,搜索用时 15 毫秒
1.
Ana Cuesta Laia Pedrola Teresa Sevilla Javier García-Planells María José Chumillas Fernando Mayordomo Eric LeGuern Ignacio Marín Juan J Vílchez Francesc Palau 《Nature genetics》2002,30(1):22-25
We identified three distinct mutations and six mutant alleles in GDAP1 in three families with axonal Charcot-Marie-Tooth (CMT) neuropathy and vocal cord paresis, which were previously linked to the CMT4A locus on chromosome 8q21.1. These results establish the molecular etiology of CMT4A (MIM 214400) and suggest that it may be associated with both axonal and demyelinating phenotypes. 相似文献
2.
TextileandUncontrolledFires Textilesarethethirdbasicrequirementforhumanlifeafterfoodandshelter.Textilesareusedforthermalprotectionagainsthostileweatherandtocovernakedness.Textilesalsoprovidecom fortinlifeintheformoffurnishings :upholstery ,carpets ,etc .… 相似文献
3.
Structure,biosynthesis and functions of glycoprotein glycans 总被引:14,自引:0,他引:14
Eric G. Berger Eckhart Buddecke Johannis P. Kamerling Akira Kobata James C. Paulson Johannes F. G. Vliegenthart 《Cellular and molecular life sciences : CMLS》1982,38(10):1129-1162
Since the pioneering work on structure and function of heteroglycans compiled in the classical books edited by A. Gottschalk in 19721, there have been several promising developments in glycoconjugate research, as reviewed in this article.In Part 1, contributed by A. Kobata, current knowledge on heteroglycan structures is presented and representative examples taken from higher organisms are given. Part 2, written by J. F. G. Vliegenthart and J. P. Kamerling, covers the most important achievements in methodology: procedures to obtain pure glycans and to analyze their structures. Part 3, contributed by J. Paulson, is devoted to biosynthesis of glycans now describable as pathways since several of the glycosyltransferases have been isolated and analyzed for specificity. In Part 4, contributed by E. Buddecke, current knowledge on functional roles of glycans is presented. It will become apparent that the prerequisite for valid work either in biosynthetic or functional context depends on solid structural information. This is particularly true whenever glycosyltransferase reaction products are being analyzed, or glycans involved in biological functions are investigated. Although in past years, a great deal of important knowledge has been gathered by use of crude glycosidase or glycosyltransferase activities (a notable example is found in reference 2), one may now postulate that glycans implicated in biological reactions should be thoroughly analyzed.This review may familiarize newcomers with the field of glycoconjugate research with special emphasis on glycoprotein glycans. Glycolipids are not included in this article as they have recently been reviewed by S. I. Hakomori3. The reader is also referred to several excellent monographs4,5 and the Proceedings of the Glycoconjugate Symposia held biannually6–8. 相似文献
4.
There is a long-standing debate in the philosophy of mind and philosophy of science regarding how best to interpret the relationship between neuroscience and psychology. It has traditionally been argued that either the two domains will evolve and change over time until they converge on a single unified account of human behaviour, or else that they will continue to work in isolation given that they identify properties and states that exist autonomously from one another (due to the multiple-realizability of psychological states). In this paper, I argue that progress in psychology and neuroscience is contingent on the fact that both of these positions are false. Contra the convergence position, I argue that the theories of psychology and the theories of neuroscience are scientifically valuable as representational tools precisely because they cannot be integrated into a single account. However, contra the autonomy position, I propose that the theories of psychology and neuroscience are deeply dependent on one another for further refinement and improvement. In this respect, there is an irreconcilable codependence between psychology and neuroscience that is necessary for both domains to improve and progress. The two domains are forever linked while simultaneously being unable to integrate. 相似文献
5.
This paper discusses a crisis of accountability that arises when scientific collaborations are massively epistemically distributed. We argue that social models of epistemic collaboration, which are social analogs to what Patrick Suppes called a “model of the experiment,” must play a role in creating accountability in these contexts. We also argue that these social models must accommodate the fact that the various agents in a collaborative project often have ineliminable, messy, and conflicting interests and values; any story about accountability in a massively distributed collaboration must therefore involve models of such interests and values and their methodological and epistemic effects. 相似文献
6.
Anne Berna François Bernier Eric Chabrière Mikael Elias Ken Scott Andrew Suh 《Cellular and molecular life sciences : CMLS》2009,66(14):2205-2218
DING proteins, identified mainly by their eponymous N-terminal sequences, are ubiquitous in living organisms. Amongst bacteria,
they are common in pseudomonads, and have been characterised with respect to genetics and structure. They form part of a wider
family of phosphate-binding proteins, with emerging roles in phosphate acquisition and pathogenicity. Many DING proteins have
been isolated in eukaryotes, in which they have been associated with very diverse biological activities, often in the context
of possible signalling roles. Disease states in which DING proteins have been implicated include rheumatoid arthritis, lithiasis,
atherosclerosis, some tumours and tumour-associated cachexia, and bacterial and viral adherence. Complete genetic and structural
characterisation of eukaryotic DING genes and proteins is still lacking, though the phosphate-binding site seems to be conserved.
Whether as bacterial proteins related to bacterial pathogenicity, or as eukaryotic components of biochemical signalling systems,
DING proteins require further study.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
7.
Stark A Lin MF Kheradpour P Pedersen JS Parts L Carlson JW Crosby MA Rasmussen MD Roy S Deoras AN Ruby JG Brennecke J;Harvard FlyBase curators;Berkeley Drosophila Genome Project Hodges E Hinrichs AS Caspi A Paten B Park SW Han MV Maeder ML Polansky BJ Robson BE Aerts S van Helden J Hassan B Gilbert DG Eastman DA Rice M Weir M Hahn MW Park Y Dewey CN Pachter L Kent WJ Haussler D Lai EC Bartel DP Hannon GJ Kaufman TC Eisen MB Clark AG Smith D Celniker SE Gelbart WM Kellis M 《Nature》2007,450(7167):219-232
8.
9.
Metagenomic and functional analysis of hindgut microbiota of a wood-feeding higher termite 总被引:6,自引:0,他引:6
Warnecke F Luginbühl P Ivanova N Ghassemian M Richardson TH Stege JT Cayouette M McHardy AC Djordjevic G Aboushadi N Sorek R Tringe SG Podar M Martin HG Kunin V Dalevi D Madejska J Kirton E Platt D Szeto E Salamov A Barry K Mikhailova N Kyrpides NC Matson EG Ottesen EA Zhang X Hernández M Murillo C Acosta LG Rigoutsos I Tamayo G Green BD Chang C Rubin EM Mathur EJ Robertson DE Hugenholtz P Leadbetter JR 《Nature》2007,450(7169):560-565
From the standpoints of both basic research and biotechnology, there is considerable interest in reaching a clearer understanding of the diversity of biological mechanisms employed during lignocellulose degradation. Globally, termites are an extremely successful group of wood-degrading organisms and are therefore important both for their roles in carbon turnover in the environment and as potential sources of biochemical catalysts for efforts aimed at converting wood into biofuels. Only recently have data supported any direct role for the symbiotic bacteria in the gut of the termite in cellulose and xylan hydrolysis. Here we use a metagenomic analysis of the bacterial community resident in the hindgut paunch of a wood-feeding 'higher' Nasutitermes species (which do not contain cellulose-fermenting protozoa) to show the presence of a large, diverse set of bacterial genes for cellulose and xylan hydrolysis. Many of these genes were expressed in vivo or had cellulase activity in vitro, and further analyses implicate spirochete and fibrobacter species in gut lignocellulose degradation. New insights into other important symbiotic functions including H2 metabolism, CO2-reductive acetogenesis and N2 fixation are also provided by this first system-wide gene analysis of a microbial community specialized towards plant lignocellulose degradation. Our results underscore how complex even a 1-microl environment can be. 相似文献
10.
Genome-wide detection and characterization of positive selection in human populations 总被引:3,自引:0,他引:3
Sabeti PC Varilly P Fry B Lohmueller J Hostetter E Cotsapas C Xie X Byrne EH McCarroll SA Gaudet R Schaffner SF Lander ES;International HapMap Consortium Frazer KA Ballinger DG Cox DR Hinds DA Stuve LL Gibbs RA Belmont JW Boudreau A Hardenbol P Leal SM Pasternak S Wheeler DA Willis TD Yu F Yang H Zeng C Gao Y Hu H Hu W Li C Lin W Liu S Pan H Tang X Wang J Wang W Yu J Zhang B Zhang Q Zhao H Zhao H Zhou J Gabriel SB Barry R Blumenstiel B Camargo A Defelice M Faggart M Goyette M Gupta S Moore J 《Nature》2007,449(7164):913-918
With the advent of dense maps of human genetic variation, it is now possible to detect positive natural selection across the human genome. Here we report an analysis of over 3 million polymorphisms from the International HapMap Project Phase 2 (HapMap2). We used 'long-range haplotype' methods, which were developed to identify alleles segregating in a population that have undergone recent selection, and we also developed new methods that are based on cross-population comparisons to discover alleles that have swept to near-fixation within a population. The analysis reveals more than 300 strong candidate regions. Focusing on the strongest 22 regions, we develop a heuristic for scrutinizing these regions to identify candidate targets of selection. In a complementary analysis, we identify 26 non-synonymous, coding, single nucleotide polymorphisms showing regional evidence of positive selection. Examination of these candidates highlights three cases in which two genes in a common biological process have apparently undergone positive selection in the same population:LARGE and DMD, both related to infection by the Lassa virus, in West Africa;SLC24A5 and SLC45A2, both involved in skin pigmentation, in Europe; and EDAR and EDA2R, both involved in development of hair follicles, in Asia. 相似文献