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排序方式: 共有149条查询结果,搜索用时 15 毫秒
121.
Hu TT Pattyn P Bakker EG Cao J Cheng JF Clark RM Fahlgren N Fawcett JA Grimwood J Gundlach H Haberer G Hollister JD Ossowski S Ottilar RP Salamov AA Schneeberger K Spannagl M Wang X Yang L Nasrallah ME Bergelson J Carrington JC Gaut BS Schmutz J Mayer KF Van de Peer Y Grigoriev IV Nordborg M Weigel D Guo YL 《Nature genetics》2011,43(5):476-481
We report the 207-Mb genome sequence of the North American Arabidopsis lyrata strain MN47 based on 8.3× dideoxy sequence coverage. We predict 32,670 genes in this outcrossing species compared to the 27,025 genes in the selfing species Arabidopsis thaliana. The much smaller 125-Mb genome of A. thaliana, which diverged from A. lyrata 10 million years ago, likely constitutes the derived state for the family. We found evidence for DNA loss from large-scale rearrangements, but most of the difference in genome size can be attributed to hundreds of thousands of small deletions, mostly in noncoding DNA and transposons. Analysis of deletions and insertions still segregating in A. thaliana indicates that the process of DNA loss is ongoing, suggesting pervasive selection for a smaller genome. The high-quality reference genome sequence for A. lyrata will be an important resource for functional, evolutionary and ecological studies in the genus Arabidopsis. 相似文献
122.
Sánchez-García Jacqueline Y. Núñez-Ríos Juan E. Soto-Pérez Manuel Cardoso-Castro Pedro Pablo Rodríguez-Magaña Alejandro 《Systemic Practice and Action Research》2020,33(1):1-25
Systemic Practice and Action Research - This article proposes a model based on the integration of systemic mechanisms such as the soft systems methodology, partial least squares path modelling and... 相似文献
123.
Gonzalez-Meljem Jose Mario Martinez-Barbera Juan Pedro 《Cellular and molecular life sciences : CMLS》2021,78(10):4521-4544
Cellular and Molecular Life Sciences - Cellular senescence is a process that can prevent tumour development in a cell autonomous manner by imposing a stable cell cycle arrest after oncogene... 相似文献
124.
MB Gerstein A Kundaje M Hariharan SG Landt KK Yan C Cheng XJ Mu E Khurana J Rozowsky R Alexander R Min P Alves A Abyzov N Addleman N Bhardwaj AP Boyle P Cayting A Charos DZ Chen Y Cheng D Clarke C Eastman G Euskirchen S Frietze Y Fu J Gertz F Grubert A Harmanci P Jain M Kasowski P Lacroute J Leng J Lian H Monahan H O'Geen Z Ouyang EC Partridge D Patacsil F Pauli D Raha L Ramirez TE Reddy B Reed M Shi T Slifer J Wang L Wu X Yang KY Yip G Zilberman-Schapira S Batzoglou A Sidow PJ Farnham RM Myers 《Nature》2012,489(7414):91-100
125.
Nuclear distribution gene C homolog (NudC) is a highly conserved gene. It has been identified in different species from fungi to mammals. The high degree of conservation,
in special in the nudC domain, suggests that they are genes with essential functions. Most of the identified genes in the family have been implicated
in cell division through the regulation of cytoplasmic dynein. As for mammalian genes, human NUDC has been implicated in the migration and proliferation of tumor cells and has therefore been considered a possible therapeutic
target. There is evidence suggesting that mammalian NudC is also implicated in the regulation of the inflammatory response and in thrombopoiesis. The presence of these other functions
not related to the interaction with molecular motors agrees with that these genes and their products are larger in size than
their microbial orthologous, indicating that they have evolved to convey additional features. 相似文献
126.
127.
This paper extends the existing literature on empirical research in the field of sovereign debt. To the authors' knowledge, only one study in the area of sovereign debt has used a variety of statistical methodologies to test the reliability of their predictions and to compare their performance against one another. However, those comparisons across models have been made in terms of different probability cut‐off points and mean squared errors. Moreover, the issue of interpretability has not been addressed in terms of interactions among explanatory variables with their correspondent debt rescheduling threshold level. The areas under the Receiver Operating Characteristic (ROC) curves are used to compare the discrimination power of statistical models. This paper tests logit, MARS, tree‐based and neural network models. Analyses of the relative importance of variables and deviance were done. All of the models rank the previous payment history as the most important explanatory variable. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
128.
In this study, we verify the existence of predictability in the Brazilian equity market. Unlike other studies in the same sense, which evaluate original series for each stock, we evaluate synthetic series created on the basis of linear models of stocks. Following the approach of Burgess (Computational Finance, 1999; 99, 297–312), we use the ‘stepwise regression’ model for the formation of models of each stock. We then use the variance ratio profile together with a Monte Carlo simulation for the selection of models with potential predictability using data from 1 April 1999 to 30 December 2003. Unlike the approach of Burgess, we carry out White's Reality Check (Econometrica, 2000; 68, 1097–1126) in order to verify the existence of positive returns for the period outside the sample from 2 January 2004 to 28 August 2007. We use the strategies proposed by Sullivan, Timmermann and White (Journal of Finance, 1999; 54, 1647–1691) and Hsu and Kuan (Journal of Financial Econometrics, 2005; 3, 606–628) amounting to 26,410 simulated strategies. Finally, using the bootstrap methodology, with 1000 simulations, we find strong evidence of predictability in the models, including transaction costs. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
129.
Chambers JC Zhang W Sehmi J Li X Wass MN Van der Harst P Holm H Sanna S Kavousi M Baumeister SE Coin LJ Deng G Gieger C Heard-Costa NL Hottenga JJ Kühnel B Kumar V Lagou V Liang L Luan J Vidal PM Mateo Leach I O'Reilly PF Peden JF Rahmioglu N Soininen P Speliotes EK Yuan X Thorleifsson G Alizadeh BZ Atwood LD Borecki IB Brown MJ Charoen P Cucca F Das D de Geus EJ Dixon AL Döring A Ehret G Eyjolfsson GI Farrall M Forouhi NG Friedrich N Goessling W Gudbjartsson DF Harris TB Hartikainen AL Heath S 《Nature genetics》2011,43(11):1131-1138
Concentrations of liver enzymes in plasma are widely used as indicators of liver disease. We carried out a genome-wide association study in 61,089 individuals, identifying 42 loci associated with concentrations of liver enzymes in plasma, of which 32 are new associations (P = 10(-8) to P = 10(-190)). We used functional genomic approaches including metabonomic profiling and gene expression analyses to identify probable candidate genes at these regions. We identified 69 candidate genes, including genes involved in biliary transport (ATP8B1 and ABCB11), glucose, carbohydrate and lipid metabolism (FADS1, FADS2, GCKR, JMJD1C, HNF1A, MLXIPL, PNPLA3, PPP1R3B, SLC2A2 and TRIB1), glycoprotein biosynthesis and cell surface glycobiology (ABO, ASGR1, FUT2, GPLD1 and ST3GAL4), inflammation and immunity (CD276, CDH6, GCKR, HNF1A, HPR, ITGA1, RORA and STAT4) and glutathione metabolism (GSTT1, GSTT2 and GGT), as well as several genes of uncertain or unknown function (including ABHD12, EFHD1, EFNA1, EPHA2, MICAL3 and ZNF827). Our results provide new insight into genetic mechanisms and pathways influencing markers of liver function. 相似文献
130.
J. D. Dunn A. J. Castro J. A. McNulty 《Cellular and molecular life sciences : CMLS》1978,34(12):1588-1589
Summary The data presented in the present study suggest that neither the ascending noradrenergic fibres confined to the MFB nor the serotonergic fibres originating in or passing through the mesencephalic raphe are essential for periodicity in body temperature. Both control and experimental groups, i.e., rats subjected to medial forebrain bundle or raphe ablation presented circadian periodicity in body temperature and neither the phase, amplitude or overall mean of experimentals differed significantly from controls. 相似文献