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排序方式: 共有259条查询结果,搜索用时 609 毫秒
201.
When you see a red ball rolling across the floor, the ball's redness, roundness and motion appear to be unified and inseparably bound together as features of the ball. But neurophysiological evidence indicates that visual features such as colour, shape and motion are processed in separate regions of the brain. Here we describe an illusion that exploits this separation, causing colour and motion to be recombined incorrectly while a stable stimulus is being viewed continuously. 相似文献
202.
Wallis JW Aerts J Groenen MA Crooijmans RP Layman D Graves TA Scheer DE Kremitzki C Fedele MJ Mudd NK Cardenas M Higginbotham J Carter J McGrane R Gaige T Mead K Walker J Albracht D Davito J Yang SP Leong S Chinwalla A Sekhon M Wylie K Dodgson J Romanov MN Cheng H de Jong PJ Osoegawa K Nefedov M Zhang H McPherson JD Krzywinski M Schein J Hillier L Mardis ER Wilson RK Warren WC 《Nature》2004,432(7018):761-764
Strategies for assembling large, complex genomes have evolved to include a combination of whole-genome shotgun sequencing and hierarchal map-assisted sequencing. Whole-genome maps of all types can aid genome assemblies, generally starting with low-resolution cytogenetic maps and ending with the highest resolution of sequence. Fingerprint clone maps are based upon complete restriction enzyme digests of clones representative of the target genome, and ultimately comprise a near-contiguous path of clones across the genome. Such clone-based maps are used to validate sequence assembly order, supply long-range linking information for assembled sequences, anchor sequences to the genetic map and provide templates for closing gaps. Fingerprint maps are also a critical resource for subsequent functional genomic studies, because they provide a redundant and ordered sampling of the genome with clones. In an accompanying paper we describe the draft genome sequence of the chicken, Gallus gallus, the first species sequenced that is both a model organism and a global food source. Here we present a clone-based physical map of the chicken genome at 20-fold coverage, containing 260 contigs of overlapping clones. This map represents approximately 91% of the chicken genome and enables identification of chicken clones aligned to positions in other sequenced genomes. 相似文献
203.
Nykjaer A Lee R Teng KK Jansen P Madsen P Nielsen MS Jacobsen C Kliemannel M Schwarz E Willnow TE Hempstead BL Petersen CM 《Nature》2004,427(6977):843-848
Sortilin (approximately 95 kDa) is a member of the recently discovered family of Vps10p-domain receptors, and is expressed in a variety of tissues, notably brain, spinal cord and muscle. It acts as a receptor for neurotensin, but predominates in regions of the nervous system that neither synthesize nor respond to this neuropeptide, suggesting that sortilin has additional roles. Sortilin is expressed during embryogenesis in areas where nerve growth factor (NGF) and its precursor, proNGF, have well-characterized effects. These neurotrophins can be released by neuronal tissues, and they regulate neuronal development through cell survival and cell death signalling. NGF regulates cell survival and cell death via binding to two different receptors, TrkA and p75NTR (ref. 10). In contrast, proNGF selectively induces apoptosis through p75NTR but not TrkA. However, not all p75NTR-expressing cells respond to proNGF, suggesting that additional membrane proteins are required for the induction of cell death. Here we report that proNGF creates a signalling complex by simultaneously binding to p75NTR and sortilin. Thus sortilin acts as a co-receptor and molecular switch governing the p75NTR-mediated pro-apoptotic signal induced by proNGF. 相似文献
204.
D. Cavallini B. Mondovì C. De Marco 《Cellular and molecular life sciences : CMLS》1957,13(11):436-438
Riassunto La formilcisteina in HCl 12N dà un assorbimento nell'ultravioletto indicante la formazione di un anello tiazolinico. La reazione è più rapida per la formilcisteina che per il glutatione e dipende dalla concentrazione dell'acido. Trattando la formicilsteina con HCl 12N, è stato preparato un composto avente le proprietà dell'acido tiazolin carbossilico, che in soluzione di fosfati a pH 7,4 dà una curva spettrofotometrica sovrapponibile a quella ottenuta in un precedente lavoro da un metabolita dell'acido tiazolidin carbossilico. Questo risultato avvalora l'ipotesi che il fegato di ratto è capace di ossidare l'anello tiazolidinico a tiazolinico. 相似文献
205.
206.
Francesca Turroni Marco Ventura Ludovica F. Buttó Sabrina Duranti Paul W. O’Toole Mary O’Connell Motherway Douwe van Sinderen 《Cellular and molecular life sciences : CMLS》2014,71(2):183-203
The human gut represents a highly complex ecosystem, which is densely colonized by a myriad of microorganisms that influence the physiology, immune function and health status of the host. Among the many members of the human gut microbiota, there are microorganisms that have co-evolved with their host and that are believed to exert health-promoting or probiotic effects. Probiotic bacteria isolated from the gut and other environments are commercially exploited, and although there is a growing list of health benefits provided by the consumption of such probiotics, their precise mechanisms of action have essentially remained elusive. Genomics approaches have provided exciting new opportunities for the identification of probiotic effector molecules that elicit specific responses to influence the physiology and immune function of their human host. In this review, we describe the current understanding of the intriguing relationships that exist between the human gut and key members of the gut microbiota such as bifidobacteria and lactobacilli, discussed here as prototypical groups of probiotic microorganisms. 相似文献
207.
Factor‐Augmented Bridge Models (FABM) and Soft Indicators to Forecast Italian Industrial Production
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This paper presents a new forecasting approach straddling the conventional methods applied to the Italian industrial production index. Specifically, the proposed method treats factor models and bridge models as complementary ingredients feeding a unique model specification. We document that the proposed approach improves upon traditional bridge models by making efficient use of the information conveyed by a large amount of survey data on manufacturing activity. Different factor algorithms are compared and, under the provision that a large estimation window is used, partial least squares outperform principal component‐based alternatives. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
208.
Meta-analysis identifies nine new loci associated with rheumatoid arthritis in the Japanese population 总被引:1,自引:0,他引:1
Okada Y Terao C Ikari K Kochi Y Ohmura K Suzuki A Kawaguchi T Stahl EA Kurreeman FA Nishida N Ohmiya H Myouzen K Takahashi M Sawada T Nishioka Y Yukioka M Matsubara T Wakitani S Teshima R Tohma S Takasugi K Shimada K Murasawa A Honjo S Matsuo K Tanaka H Tajima K Suzuki T Iwamoto T Kawamura Y Tanii H Okazaki Y Sasaki T Gregersen PK Padyukov L Worthington J Siminovitch KA Lathrop M Taniguchi A Takahashi A Tokunaga K Kubo M Nakamura Y Kamatani N Mimori T Plenge RM Yamanaka H Momohara S Yamada R 《Nature genetics》2012,44(5):511-516
Rheumatoid arthritis is a common autoimmune disease characterized by chronic inflammation. We report a meta-analysis of genome-wide association studies (GWAS) in a Japanese population including 4,074 individuals with rheumatoid arthritis (cases) and 16,891 controls, followed by a replication in 5,277 rheumatoid arthritis cases and 21,684 controls. Our study identified nine loci newly associated with rheumatoid arthritis at a threshold of P < 5.0 × 10(-8), including B3GNT2, ANXA3, CSF2, CD83, NFKBIE, ARID5B, PDE2A-ARAP1, PLD4 and PTPN2. ANXA3 was also associated with susceptibility to systemic lupus erythematosus (P = 0.0040), and B3GNT2 and ARID5B were associated with Graves' disease (P = 3.5 × 10(-4) and 2.9 × 10(-4), respectively). We conducted a multi-ancestry comparative analysis with a previous meta-analysis in individuals of European descent (5,539 rheumatoid arthritis cases and 20,169 controls). This provided evidence of shared genetic risks of rheumatoid arthritis between the populations. 相似文献
209.
Albagha OM Wani SE Visconti MR Alonso N Goodman K Brandi ML Cundy T Chung PY Dargie R Devogelaer JP Falchetti A Fraser WD Gennari L Gianfrancesco F Hooper MJ Van Hul W Isaia G Nicholson GC Nuti R Papapoulos S Montes Jdel P Ratajczak T Rea SL Rendina D Gonzalez-Sarmiento R Di Stefano M Ward LC Walsh JP Ralston SH;Genetic Determinants of Paget's Disease 《Nature genetics》2011,43(7):685-689
Paget's disease of bone (PDB) is a common disorder characterized by focal abnormalities of bone remodeling. We previously identified variants at the CSF1, OPTN and TNFRSF11A loci as risk factors for PDB by genome-wide association study. Here we extended this study, identified three new loci and confirmed their association with PDB in 2,215 affected individuals (cases) and 4,370 controls from seven independent populations. The new associations were with rs5742915 within PML on 15q24 (odds ratio (OR) = 1.34, P = 1.6 × 10(-14)), rs10498635 within RIN3 on 14q32 (OR = 1.44, P = 2.55 × 10(-11)) and rs4294134 within NUP205 on 7q33 (OR = 1.45, P = 8.45 × 10(-10)). Our data also confirmed the association of TM7SF4 (rs2458413, OR = 1.40, P = 7.38 × 10(-17)) with PDB. These seven loci explained ~13% of the familial risk of PDB. These studies provide new insights into the genetic architecture and pathophysiology of PDB. 相似文献
210.
Di Cesare A Del Piccolo P Zacchetti D Grohovaz F 《Cellular and molecular life sciences : CMLS》2006,63(21):2546-2553
Astrocytes are a heterogeneous population of cells that are endowed with a great variety of receptors for neurotransmitters
and neuromodulators. Recently prostaglandin E2 has attracted great interest since it is not only released by astrocytes but also activates receptors coupled to either phospholipase
C or adenylyl cyclase. We report that EP2 receptor stimulation triggers cAMP production but also causes release of Ca2+ from intracellular stores. This effect is shared by other receptors similarly coupled to adenylyl cyclase and elicited by
direct stimulation of the enzyme or application of cAMP analogues. However, the stimulation of the Ca2+ response by cAMP is not mediated by protein kinase A, since a specific antagonist of this kinase had no effect. Such a cross-talk
between cAMP and Ca2+ was not observed in all astrocytes. It might therefore reflect a specific resource of either a subpopulation or astrocytes
in a specific functional state.
Received 6 June 2006; received after revision 25 July 2006; accepted 31 August 2006 相似文献