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1.
Sluijs A Brinkhuis H Schouten S Bohaty SM John CM Zachos JC Reichart GJ Sinninghe Damsté JS Crouch EM Dickens GR 《Nature》2007,450(7173):1218-1221
The start of the Palaeocene/Eocene thermal maximum--a period of exceptional global warming about 55 million years ago--is marked by a prominent negative carbon isotope excursion that reflects a massive input of 13C-depleted ('light') carbon to the ocean-atmosphere system. It is often assumed that this carbon injection initiated the rapid increase in global surface temperatures and environmental change that characterize the climate perturbation, but the exact sequence of events remains uncertain. Here we present chemical and biotic records of environmental change across the Palaeocene/Eocene boundary from two sediment sections in New Jersey that have high sediment accumulation rates. We show that the onsets of environmental change (as recorded by the abundant occurrence ('acme') of the dinoflagellate cyst Apectodinium) and of surface-ocean warming (as evidenced by the palaeothermometer TEX86) preceded the light carbon injection by several thousand years. The onset of the Apectodinium acme also precedes the carbon isotope excursion in sections from the southwest Pacific Ocean and the North Sea, indicating that the early onset of environmental change was not confined to the New Jersey shelf. The lag of approximately 3,000 years between the onset of warming in New Jersey shelf waters and the carbon isotope excursion is consistent with the hypothesis that bottom water warming caused the injection of 13C-depleted carbon by triggering the dissociation of submarine methane hydrates, but the cause of the early warming remains uncertain. 相似文献
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Santen GW Aten E Sun Y Almomani R Gilissen C Nielsen M Kant SG Snoeck IN Peeters EA Hilhorst-Hofstee Y Wessels MW den Hollander NS Ruivenkamp CA van Ommen GJ Breuning MH den Dunnen JT van Haeringen A Kriek M 《Nature genetics》2012,44(4):379-380
We identified de novo truncating mutations in ARID1B in three individuals with Coffin-Siris syndrome (CSS) by exome sequencing. Array-based copy-number variation (CNV) analysis in 2,000 individuals with intellectual disability revealed deletions encompassing ARID1B in 3 subjects with phenotypes partially overlapping that of CSS. Taken together with published data, these results indicate that haploinsufficiency of the ARID1B gene, which encodes an epigenetic modifier of chromatin structure, is an important cause of CSS and is potentially a common cause of intellectual disability and speech impairment. 相似文献
3.
Haislip JB Nysewander MC Reichart DE Levan A Tanvir N Cenko SB Fox DB Price PA Castro-Tirado AJ Gorosabel J Evans CR Figueredo E MacLeod CL Kirschbrown JR Jelinek M Guziy S de Ugarte Postigo A Cypriano ES LaCluyze A Graham J Priddey R Chapman R Rhoads J Fruchter AS Lamb DQ Kouveliotou C Wijers RA Bayliss MB Schmidt BP Soderberg AM Kulkarni SR Harrison FA Moon DS Gal-Yam A Kasliwal MM Hudec R Vitek S Kubanek P Crain JA Foster AC Clemens JC Bartelme JW Canterna R Hartmann DH Henden AA Klose S 《Nature》2006,440(7081):181-183
Gamma-ray bursts (GRBs) and their afterglows are the most brilliant transient events in the Universe. Both the bursts themselves and their afterglows have been predicted to be visible out to redshifts of z approximately 20, and therefore to be powerful probes of the early Universe. The burst GRB 000131, at z = 4.50, was hitherto the most distant such event identified. Here we report the discovery of the bright near-infrared afterglow of GRB 050904 (ref. 4). From our measurements of the near-infrared afterglow, and our failure to detect the optical afterglow, we determine the photometric redshift of the burst to be z = 6.39 - 0.12 + 0.11 (refs 5-7). Subsequently, it was measured spectroscopically to be z = 6.29 +/- 0.01, in agreement with our photometric estimate. These results demonstrate that GRBs can be used to trace the star formation, metallicity, and reionization histories of the early Universe. 相似文献
4.
van Overveld PG Lemmers RJ Sandkuijl LA Enthoven L Winokur ST Bakels F Padberg GW van Ommen GJ Frants RR van der Maarel SM 《Nature genetics》2003,35(4):315-317
The autosomal dominant myopathy facioscapulohumeral muscular dystrophy (FSHD1, OMIM 158900) is caused by contraction of the D4Z4 repeat array on 4qter. We show that this contraction causes marked hypomethylation of the contracted D4Z4 allele in individuals with FSHD1. Individuals with phenotypic FSHD1, who are clinically identical to FSHD1 but have an unaltered D4Z4, also have hypomethylation of D4Z4. These results strongly suggest that hypomethylation of D4Z4 is a key event in the cascade of epigenetic events causing FSHD1. 相似文献
5.
Induced ncRNAs allosterically modify RNA-binding proteins in cis to inhibit transcription 总被引:2,自引:0,他引:2
Wang X Arai S Song X Reichart D Du K Pascual G Tempst P Rosenfeld MG Glass CK Kurokawa R 《Nature》2008,454(7200):126-130
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合作对策的妥协值 总被引:1,自引:0,他引:1
张纪江 《系统工程理论与实践》1996,16(10):98-112
本文全面描述了几种熟知的合作对策理论中的妥协值及其应用。特别介绍了TU-对策的τ-值、谈判问题的Raifa-Kalai-Smorodinsky解、NTU-对策的妥协值。 相似文献
8.
Facioscapulohumeral muscular dystrophy is uniquely associated with one of the two variants of the 4q subtelomere 总被引:12,自引:0,他引:12
Lemmers RJ de Kievit P Sandkuijl L Padberg GW van Ommen GJ Frants RR van der Maarel SM 《Nature genetics》2002,32(2):235-236
Contractions in the polymorphic D4Z4 repeat array of subtelomere 4qter cause autosomal dominant facioscapulohumeral muscular dystrophy in humans. A polymorphic segment of 10 kb directly distal to D4Z4 exists in two allelic forms, 4qA and 4qB. Although both alleles are equally common in the general population, we now report that FSHD is associated solely with the 4qA allele. 相似文献
9.
van Ommen GJ 《Nature genetics》2005,37(4):333-334
10.
An expression profile for diagnosis of lymph node metastases from primary head and neck squamous cell carcinomas 总被引:15,自引:0,他引:15
Roepman P Wessels LF Kettelarij N Kemmeren P Miles AJ Lijnzaad P Tilanus MG Koole R Hordijk GJ van der Vliet PC Reinders MJ Slootweg PJ Holstege FC 《Nature genetics》2005,37(2):182-186
Metastasis is the process by which cancers spread to distinct sites in the body. It is the principal cause of death in individuals suffering from cancer. For some types of cancer, early detection of metastasis at lymph nodes close to the site of the primary tumor is pivotal for appropriate treatment. Because it can be difficult to detect lymph node metastases reliably, many individuals currently receive inappropriate treatment. We show here that DNA microarray gene-expression profiling can detect lymph node metastases for primary head and neck squamous cell carcinomas that arise in the oral cavity and oropharynx. The predictor, established with an 82-tumor training set, outperforms current clinical diagnosis when independently validated. The 102 predictor genes offer unique insights into the processes underlying metastasis. The results show that the metastatic state can be deciphered from the primary tumor gene-expression pattern and that treatment can be substantially improved. 相似文献