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排序方式: 共有90条查询结果,搜索用时 31 毫秒
1.
A SUMOylation-defective MITF germline mutation predisposes to melanoma and renal carcinoma 总被引:1,自引:0,他引:1
Bertolotto C Lesueur F Giuliano S Strub T de Lichy M Bille K Dessen P d'Hayer B Mohamdi H Remenieras A Maubec E de la Fouchardière A Molinié V Vabres P Dalle S Poulalhon N Martin-Denavit T Thomas L Andry-Benzaquen P Dupin N Boitier F Rossi A Perrot JL Labeille B Robert C Escudier B Caron O Brugières L Saule S Gardie B Gad S Richard S Couturier J Teh BT Ghiorzo P Pastorino L Puig S Badenas C Olsson H Ingvar C Rouleau E Lidereau R Bahadoran P Vielh P Corda E Blanché H Zelenika D 《Nature》2011,480(7375):94-98
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Horvath A Boikos S Giatzakis C Robinson-White A Groussin L Griffin KJ Stein E Levine E Delimpasi G Hsiao HP Keil M Heyerdahl S Matyakhina L Libè R Fratticci A Kirschner LS Cramer K Gaillard RC Bertagna X Carney JA Bertherat J Bossis I Stratakis CA 《Nature genetics》2006,38(7):794-800
Phosphodiesterases (PDEs) regulate cyclic nucleotide levels. Increased cyclic AMP (cAMP) signaling has been associated with PRKAR1A or GNAS mutations and leads to adrenocortical tumors and Cushing syndrome. We investigated the genetic source of Cushing syndrome in individuals with adrenocortical hyperplasia that was not caused by known defects. We performed genome-wide SNP genotyping, including the adrenocortical tumor DNA. The region with the highest probability to harbor a susceptibility gene by loss of heterozygosity (LOH) and other analyses was 2q31-2q35. We identified mutations disrupting the expression of the PDE11A isoform-4 gene (PDE11A) in three kindreds. Tumor tissues showed 2q31-2q35 LOH, decreased protein expression and high cyclic nucleotide levels and cAMP-responsive element binding protein (CREB) phosphorylation. PDE11A codes for a dual-specificity PDE that is expressed in adrenal cortex and is partially inhibited by tadalafil and other PDE inhibitors; its germline inactivation is associated with adrenocortical hyperplasia, suggesting another means by which dysregulation of cAMP signaling causes endocrine tumors. 相似文献
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Jérôme Lamy 《Annals of science》2013,70(1):75-98
Les observatoires occidentaux se transforment en véritable usine scientifique à partir du milieu du 19e siècle. L'astrométrie symbolise ce passage à une économie industrieuse des pratiques scientifiques. Le chronographe imprimant, qui permet de réduire les équations personnelles des observateurs, s'impose, d'abord aux Etats-Unis, puis en Angleterre, en instrument-emblème de cette transformation profonde. En France, les initiatives de l'astronome Liais restent prototypiques. Ce n'est qu'au début du 20e siècle, par les voies détournées de l'observatoire d'Hendaye et de l'abbé Verschaffel, que le chronographe imprimant fait son retour et conquiert les espaces savants. La centralisation excessive de l'astronomie française, l'autoritarisme du directeur de l'Observatoire de Paris Urbain Le Verrier, et la faiblesse du marché des instruments expliquent pourquoi le chronographe imprimant n'a fait souche que très tardivement en France. 相似文献
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Imprinted microRNA genes transcribed antisense to a reciprocally imprinted retrotransposon-like gene 总被引:18,自引:0,他引:18
Seitz H Youngson N Lin SP Dalbert S Paulsen M Bachellerie JP Ferguson-Smith AC Cavaillé J 《Nature genetics》2003,34(3):261-262
MicroRNAs (miRNAs) are an abundant class of RNAs that are approximately 21-25 nucleotides (nt) long, interact with mRNAs and trigger either translation repression or RNA cleavage (RNA interference, RNAi) depending on the degree of complementarity with their targets. Here we show that the imprinted mouse distal chromosome 12 locus encodes two miRNA genes expressed from the maternally inherited chromosome and antisense to a retrotransposon-like gene (Rtl1) expressed only from the paternal allele. 相似文献
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Zusammenfassung Für das Aconitum-Alkaloid Napellin wurden auf Grund einer eingehenden Diskussion des Tatsachenmaterials die Strukturen XI bzw. X vorgeschlagen. Das Alkaloid Songorin ist das dazugehörige Ring-D-Keton. 相似文献
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Marchis F Hestroffer D Descamps P Berthier J Bouchez AH Campbell RD Chin JC van Dam MA Hartman SK Johansson EM Lafon RE Le Mignant D de Pater I Stomski PJ Summers DM Vachier F Wizinovich PL Wong MH 《Nature》2006,439(7076):565-567
The Trojan population consists of two swarms of asteroids following the same orbit as Jupiter and located at the L4 and L5 stable Lagrange points of the Jupiter-Sun system (leading and following Jupiter by 60 degrees ). The asteroid 617 Patroclus is the only known binary Trojan. The orbit of this double system was hitherto unknown. Here we report that the components, separated by 680 km, move around the system's centre of mass, describing a roughly circular orbit. Using this orbital information, combined with thermal measurements to estimate the size of the components, we derive a very low density of 0.8(- 0.1)+0.2 g cm(-3). The components of 617 Patroclus are therefore very porous or composed mostly of water ice, suggesting that they could have been formed in the outer part of the Solar System. 相似文献