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51.
J. P. Yardley H. Fletcher III P. B. Russell 《Cellular and molecular life sciences : CMLS》1978,34(9):1124-1125
Summary Synthesis and preliminary biological activity of (–)cis-2(-dimethylamino-m-hydroxybenzyl)cyclohexanol, a novel analgesic agent is described. 相似文献
52.
White RS Smith LK Roberts AW Christie PA Kusznir NJ;iSIMM Team Roberts AM Healy D Spitzer R Chappell A Eccles JD Fletcher R Hurst N Lunnon Z Parkin CJ Tymms VJ 《Nature》2008,452(7186):460-464
When continents break apart, the rifting is sometimes accompanied by the production of large volumes of molten rock. The total melt volume, however, is uncertain, because only part of it has erupted at the surface. Furthermore, the cause of the magmatism is still disputed-specifically, whether or not it is due to increased mantle temperatures. We recorded deep-penetration normal-incidence and wide-angle seismic profiles across the Faroe and Hatton Bank volcanic margins in the northeast Atlantic. Here we show that near the Faroe Islands, for every 1 km along strike, 360-400 km(3) of basalt is extruded, while 540-600 km(3) is intruded into the continent-ocean transition. We find that lower-crustal intrusions are focused mainly into a narrow zone approximately 50 km wide on the transition, although extruded basalts flow more than 100 km from the rift. Seismic profiles show that the melt is intruded into the lower crust as sills, which cross-cut the continental fabric, rather than as an 'underplate' of 100 per cent melt, as has often been assumed. Evidence from the measured seismic velocities and from igneous thicknesses are consistent with the dominant control on melt production being increased mantle temperatures, with no requirement for either significant active small-scale mantle convection under the rift or the presence of fertile mantle at the time of continental break-up, as has previously been suggested for the North Atlantic Ocean. 相似文献
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Konstantin Knoblich Hong-Xing Wang Chandan Sharma Anne L. Fletcher Shannon J. Turley Martin E. Hemler 《Cellular and molecular life sciences : CMLS》2014,71(7):1305-1314
Ablation of tetraspanin protein TSPAN12 from human MDA-MB-231 cells significantly decreased primary tumor xenograft growth, while increasing tumor apoptosis. Furthermore, TSPAN12 removal markedly enhanced tumor-endothelial interactions and increased metastasis to mouse lungs. TSPAN12 removal from human MDA-MB-231 cells also caused diminished association between FZD4 (a key canonical Wnt pathway receptor) and its co-receptor LRP5. The result likely explains substantially enhanced proteosomal degradation of β-catenin, a key effecter of canonical Wnt signaling. Consistent with disrupted canonical Wnt signaling, TSPAN12 ablation altered expression of LRP5, Naked 1 and 2, DVL2, DVL3, Axin 1, and GSKβ3 proteins. TSPAN12 ablation also altered expression of several genes regulated by β-catenin (e.g. CCNA1, CCNE2, WISP1, ID4, SFN, ME1) that may help to explain altered tumor growth and metastasis. In conclusion, these results provide the first evidence for TSPAN12 playing a role in supporting primary tumor growth and suppressing metastasis. TSPAN12 appears to function by stabilizing FZD4–LRP5 association, in support of canonical Wnt-pathway signaling, leading to enhanced β-catenin expression and function. 相似文献
55.
I Perrault S Hanein X Zanlonghi V Serre M Nicouleau S Defoort-Delhemmes N Delphin L Fares-Taie S Gerber O Xerri C Edelson A Goldenberg A Duncombe G Le Meur C Hamel E Silva P Nitschke P Calvas A Munnich O Roche H Dollfus J Kaplan JM Rozet 《Nature genetics》2012,44(9):975-977
In addition to its activity in nicotinamide adenine dinucleotide (NAD(+)) synthesis, the nuclear nicotinamide mononucleotide adenyltransferase NMNAT1 acts as a chaperone that protects against neuronal activity-induced degeneration. Here we report that compound heterozygous and homozygous NMNAT1 mutations cause severe neonatal neurodegeneration of the central retina and early-onset optic atrophy in 22 unrelated individuals. Their clinical presentation is consistent with Leber congenital amaurosis and suggests that the mutations affect neuroprotection of photoreceptor cells. 相似文献
56.
Ghoussaini M Fletcher O Michailidou K Turnbull C Schmidt MK Dicks E Dennis J Wang Q Humphreys MK Luccarini C Baynes C Conroy D Maranian M Ahmed S Driver K Johnson N Orr N dos Santos Silva I Waisfisz Q Meijers-Heijboer H Uitterlinden AG Rivadeneira F;Netherlands Collaborative Group on Hereditary Breast Ovarian Cancer 《Nature genetics》2012,44(3):312-318
Breast cancer is the most common cancer among women. To date, 22 common breast cancer susceptibility loci have been identified accounting for ~8% of the heritability of the disease. We attempted to replicate 72 promising associations from two independent genome-wide association studies (GWAS) in ~70,000 cases and ~68,000 controls from 41 case-control studies and 9 breast cancer GWAS. We identified three new breast cancer risk loci at 12p11 (rs10771399; P = 2.7 × 10(-35)), 12q24 (rs1292011; P = 4.3 × 10(-19)) and 21q21 (rs2823093; P = 1.1 × 10(-12)). rs10771399 was associated with similar relative risks for both estrogen receptor (ER)-negative and ER-positive breast cancer, whereas the other two loci were associated only with ER-positive disease. Two of the loci lie in regions that contain strong plausible candidate genes: PTHLH (12p11) has a crucial role in mammary gland development and the establishment of bone metastasis in breast cancer, and NRIP1 (21q21) encodes an ER cofactor and has a role in the regulation of breast cancer cell growth. 相似文献
57.
The CLE family of plant polypeptide signaling molecules 总被引:4,自引:0,他引:4
Polypeptide ligands have long been recognized as primary signaling molecules in diverse physiological processes in animal systems. Recent studies in plants have provided major breakthroughs with the discovery that small polypeptides are also involved in many plant biological processes, indicating that the use of polypeptides as signaling molecules in cell-to-cell communication is evolutionarily conserved. The CLAVATA3 (CLV3)/ENDOSPERM SURROUNDING REGION (ESR)-related (CLE) proteins are currently the best understood family of small polypeptides in plants. The recent isolation of MCLV3 from Arabidopsis and TDIF from a Zinnia cell culture system indicates that biologically active CLE polypeptides are produced by post-translational proteolysis and modification, similar to peptide hormone production in animals and yeast. Here, we review exciting discoveries involving the identification of the CLE proteins and their functions in various aspects of plant development, including restriction of stem cell accumulation by CLV3 and inhibition of xylem differentiation by TDIF. 相似文献
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Easton DF Pooley KA Dunning AM Pharoah PD Thompson D Ballinger DG Struewing JP Morrison J Field H Luben R Wareham N Ahmed S Healey CS Bowman R;SEARCH collaborators Meyer KB Haiman CA Kolonel LK Henderson BE Le Marchand L Brennan P Sangrajrang S Gaborieau V Odefrey F Shen CY Wu PE Wang HC Eccles D Evans DG Peto J Fletcher O Johnson N Seal S Stratton MR Rahman N Chenevix-Trench G Bojesen SE Nordestgaard BG Axelsson CK Garcia-Closas M Brinton L Chanock S Lissowska J Peplonska B Nevanlinna H 《Nature》2007,447(7148):1087-1093
Breast cancer exhibits familial aggregation, consistent with variation in genetic susceptibility to the disease. Known susceptibility genes account for less than 25% of the familial risk of breast cancer, and the residual genetic variance is likely to be due to variants conferring more moderate risks. To identify further susceptibility alleles, we conducted a two-stage genome-wide association study in 4,398 breast cancer cases and 4,316 controls, followed by a third stage in which 30 single nucleotide polymorphisms (SNPs) were tested for confirmation in 21,860 cases and 22,578 controls from 22 studies. We used 227,876 SNPs that were estimated to correlate with 77% of known common SNPs in Europeans at r2 > 0.5. SNPs in five novel independent loci exhibited strong and consistent evidence of association with breast cancer (P < 10(-7)). Four of these contain plausible causative genes (FGFR2, TNRC9, MAP3K1 and LSP1). At the second stage, 1,792 SNPs were significant at the P < 0.05 level compared with an estimated 1,343 that would be expected by chance, indicating that many additional common susceptibility alleles may be identifiable by this approach. 相似文献
60.