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排序方式: 共有239条查询结果,搜索用时 31 毫秒
131.
Banerji S Cibulskis K Rangel-Escareno C Brown KK Carter SL Frederick AM Lawrence MS Sivachenko AY Sougnez C Zou L Cortes ML Fernandez-Lopez JC Peng S Ardlie KG Auclair D Bautista-Piña V Duke F Francis J Jung J Maffuz-Aziz A Onofrio RC Parkin M Pho NH Quintanar-Jurado V Ramos AH Rebollar-Vega R Rodriguez-Cuevas S Romero-Cordoba SL Schumacher SE Stransky N Thompson KM Uribe-Figueroa L Baselga J Beroukhim R Polyak K Sgroi DC Richardson AL Jimenez-Sanchez G Lander ES Gabriel SB Garraway LA Golub TR 《Nature》2012,486(7403):405-409
132.
The gene mutated in ataxia-ocular apraxia 1 encodes the new HIT/Zn-finger protein aprataxin 总被引:1,自引:0,他引:1
Moreira MC Barbot C Tachi N Kozuka N Uchida E Gibson T Mendonça P Costa M Barros J Yanagisawa T Watanabe M Ikeda Y Aoki M Nagata T Coutinho P Sequeiros J Koenig M 《Nature genetics》2001,29(2):189-193
The newly recognized ataxia-ocular apraxia 1 (AOA1; MIM 208920) is the most frequent cause of autosomal recessive ataxia in Japan and is second only to Friedreich ataxia in Portugal. It shares several neurological features with ataxia-telangiectasia, including early onset ataxia, oculomotor apraxia and cerebellar atrophy, but does not share its extraneurological features (immune deficiency, chromosomal instability and hypersensitivity to X-rays). AOA1 is also characterized by axonal motor neuropathy and the later decrease of serum albumin levels and elevation of total cholesterol. We have identified the gene causing AOA1 and the major Portuguese and Japanese mutations. This gene encodes a new, ubiquitously expressed protein that we named aprataxin. This protein is composed of three domains that share distant homology with the amino-terminal domain of polynucleotide kinase 3'- phosphatase (PNKP), with histidine-triad (HIT) proteins and with DNA-binding C2H2 zinc-finger proteins, respectively. PNKP is involved in DNA single-strand break repair (SSBR) following exposure to ionizing radiation and reactive oxygen species. Fragile-HIT proteins (FHIT) cleave diadenosine tetraphosphate, which is potentially produced during activation of the SSBR complex. The results suggest that aprataxin is a nuclear protein with a role in DNA repair reminiscent of the function of the protein defective in ataxia-telangiectasia, but that would cause a phenotype restricted to neurological signs when mutant. 相似文献
133.
Sicardy B Widemann T Lellouch E Veillet C Cuillandre JC Colas F Roques F Beisker W Kretlow M Lagrange AM Gendron E Lacombe F Lecacheux J Birnbaum C Fienga A Leyrat C Maury A Raynaud E Renner S Schultheis M Brooks K Delsanti A Hainaut OR Gilmozzi R Lidman C Spyromilio J Rapaport M Rosenzweig P Naranjo O Porras L Díaz F Calderón H Carrillo S Carvajal A Recalde E Cavero LG Montalvo C Barría D Campos R Duffard R Levato H 《Nature》2003,424(6945):168-170
Pluto's tenuous nitrogen atmosphere was first detected by the imprint left on the light curve of a star that was occulted by the planet in 1985 (ref. 1), and studied more extensively during a second occultation event in 1988 (refs 2-6). These events are, however, quite rare and Pluto's atmosphere remains poorly understood, as in particular the planet has not yet been visited by a spacecraft. Here we report data from the first occultations by Pluto since 1988. We find that, during the intervening 14 years, there seems to have been a doubling of the atmospheric pressure, a probable seasonal effect on Pluto. 相似文献
134.
In the presentpaper we will consider A-bimodule algebra for a regular multiplier Hopf algebra 《河南师范大学学报(自然科学版)》2003,31(3):120-120
In the present paper, we will consider A-bimodule algebra for a regular multiplier Hopf algebra (A,Δ). Using bimodule algebra, we construct the twisted smash product of multiplier Hopf algebras. 相似文献
135.
一、网络防火墙技术网络防火墙技术作为内部网络与外部网络之间的第一道安全屏障,是最先受到人们重视的网络安全技术,就其产品的主流趋势而言,大多数代理服务器(也称应用网关)集成了包滤技术。我们应该在哪些地方部署防火墙呢?首先,安装防火墙的位置应该是公司内部网络与外部In 相似文献
136.
Mutant P450 oxidoreductase causes disordered steroidogenesis with and without Antley-Bixler syndrome
Flück CE Tajima T Pandey AV Arlt W Okuhara K Verge CF Jabs EW Mendonça BB Fujieda K Miller WL 《Nature genetics》2004,36(3):228-230
Deficient activities of multiple steroidogenic enzymes have been reported without and with Antley-Bixler syndrome (ABS), but mutations of corresponding cytochrome P450 enzymes have not been found. We identified mutations in POR, encoding P450 oxidoreductase, the obligate electron donor for these enzymes, in a woman with amenorrhea and three children with ABS, even though knock-out of POR is embryonically lethal in mice. Mutations of POR also affect drug-metabolizing P450 enzymes, explaining the association of ABS with maternal fluconazole ingestion. 相似文献
137.
Simpson AJ Reinach FC Arruda P Abreu FA Acencio M Alvarenga R Alves LM Araya JE Baia GS Baptista CS Barros MH Bonaccorsi ED Bordin S Bové JM Briones MR Bueno MR Camargo AA Camargo LE Carraro DM Carrer H Colauto NB Colombo C Costa FF Costa MC Costa-Neto CM Coutinho LL Cristofani M Dias-Neto E Docena C El-Dorry H Facincani AP Ferreira AJ Ferreira VC Ferro JA Fraga JS França SC Franco MC Frohme M Furlan LR Garnier M Goldman GH Goldman MH Gomes SL Gruber A Ho PL Hoheisel JD Junqueira ML Kemper EL 《Nature》2000,406(6792):151-159
Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically important plant diseases. Here we report the complete genome sequence of X. fastidiosa clone 9a5c, which causes citrus variegated chlorosis--a serious disease of orange trees. The genome comprises a 52.7% GC-rich 2,679,305-base-pair (bp) circular chromosome and two plasmids of 51,158 bp and 1,285 bp. We can assign putative functions to 47% of the 2,904 predicted coding regions. Efficient metabolic functions are predicted, with sugars as the principal energy and carbon source, supporting existence in the nutrient-poor xylem sap. The mechanisms associated with pathogenicity and virulence involve toxins, antibiotics and ion sequestration systems, as well as bacterium-bacterium and bacterium-host interactions mediated by a range of proteins. Orthologues of some of these proteins have only been identified in animal and human pathogens; their presence in X. fastidiosa indicates that the molecular basis for bacterial pathogenicity is both conserved and independent of host. At least 83 genes are bacteriophage-derived and include virulence-associated genes from other bacteria, providing direct evidence of phage-mediated horizontal gene transfer. 相似文献
138.
Liliana Argueta-Figuero Raúl A. Morales-Luckie Rogelio J. Scougall-Vilchis Oscar F. Olea-Mejía 《自然科学进展(英文版)》2014,24(4):321-328
The antibacterial effect is a desirable property in dental materials.Development of simple methods for the preparation of nanosized metal particles has attracted significant attention because of their future applications due to unusual size-dependent antibacterial properties.Copper(Cu),Nickel(Ni) and bimetallic Cu–Ni nanoparticles were prepared by a simple chemical method and their antibacterial activity was tested against the widely used standard human pathogens Staphylococcus aureus(gram-negative) and Escherichia coli(gram-positive).Additionally,these nanoparticles were tested against the dental pathogen Streptococcus mutans.Our results are promising for potential use in dental materials science. 相似文献
139.
辽河西部凹陷886个水样分析化验测试数据表明,地层水型主要为低矿化度的NaHCO3水型,94.3%的地层水化学组分为HCO3-、Cl-、Na+,NaHCO3和NaCl是其主要的表现形式 相似文献
140.
地层抬升剥蚀过程对于油气成藏的影响不仅表现为破坏性,还有建设性作用。研究认为地层抬升剥蚀过程中温度降低、砂体回弹及不均衡剥蚀造成的区域性水流等因素形成的异常低压,为油 相似文献