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1.
DNA clones specifying the murine granulocyte-macrophage colony stimulating factor have been isolated. This haematopoietic growth factor is encoded by a unique gene specifying a messenger RNA of 1,200 nucleotides and a polypeptide of 118 amino acids. It bears no structural similarity to the functionally related factor, interleukin-3, described recently.  相似文献   
2.
Résumé Les tanins de l'acide chlorogénique s'accumulent immédiatement après que les racines d'ignames ont été soumises à des chocs de 10 à 44 (0.6–2.66 kg/cm2), consistant en une pulsation de la pression comparable à une rafale d'air dans un tube. L'accumulation des tanins est inversement proportionelle à la pression. Mais, l'acide chlorogénique s'accumule progressivement avec élèvation du niveau du choc.  相似文献   
3.
Summary Results from this study indicate that a fish density stress syndrome exists for red blood cell morphology. Smaller (by 3.5%) and rounder (by 0.6%) red blood cells were consistently found in intensive fish cultures.Acknowledgments. This work was conducted as part of the Federal Interagency Energy/Environmental Research and Development Program with funds administered through the Environmental Protection Agency (EPA Contract No. EPA-IAG-D8-E721-DR, TVA Contract No. TV-41967A). Dr Ralph H. Brooks and Billy G. Isom are acknowledged for making this study possible. The data were kindly donated by Dr R.W. Williams and W.E. Barksdale, both formerly with the Department of Biology, University of North Alabama, Florence, Alabama.  相似文献   
4.
Fischer SE  Butler MD  Pan Q  Ruvkun G 《Nature》2008,455(7212):491-496
Mutations that enhance the response to double-stranded RNA (dsRNA) have revealed components of the RNA interference (RNAi) pathway or related small RNA pathways. To explore these small RNA pathways, we screened for Caenorhabditis elegans mutants displaying an enhanced response to exogenous dsRNAs. Here we describe the isolation of mutations in two adjacent, divergently transcribed open reading frames (eri-6 and eri-7) that fail to complement. eri-6 and eri-7 produce separate pre-messenger RNAs (pre-mRNAs) that are trans-spliced to form a functional mRNA, eri-6/7. Trans-splicing of eri-6/7 is mediated by a direct repeat that flanks the eri-6 gene. Adenosine to inosine editing within untranslated regions of eri-6 and eri-7 pre-mRNAs reveals a double-stranded pre-mRNA intermediate, forming in the nucleus before splicing occurs. The ERI-6/7 protein is a superfamily I helicase that both negatively regulates the exogenous RNAi pathway and functions in an endogenous RNAi pathway.  相似文献   
5.
Protein-protein interaction analyses have uncovered a ciliary and basal body protein network that, when disrupted, can result in nephronophthisis (NPHP), Leber congenital amaurosis, Senior-L?ken syndrome (SLSN) or Joubert syndrome (JBTS). However, details of the molecular mechanisms underlying these disorders remain poorly understood. RPGRIP1-like protein (RPGRIP1L) is a homolog of RPGRIP1 (RPGR-interacting protein 1), a ciliary protein defective in Leber congenital amaurosis. We show that RPGRIP1L interacts with nephrocystin-4 and that mutations in the gene encoding nephrocystin-4 (NPHP4) that are known to cause SLSN disrupt this interaction. RPGRIP1L is ubiquitously expressed, and its protein product localizes to basal bodies. Therefore, we analyzed RPGRIP1L as a candidate gene for JBTS and identified loss-of-function mutations in three families with typical JBTS, including the characteristic mid-hindbrain malformation. This work identifies RPGRIP1L as a gene responsible for JBTS and establishes a central role for cilia and basal bodies in the pathophysiology of this disorder.  相似文献   
6.
Based on a vector error correction model we produce conditional euro area inflation forecasts. We use real‐time data on M3 and HICP, and include real GPD, the 3‐month EURIBOR and the 10‐year government bond yield as control variables. Real money growth and the term spread enter the system as stationary linear combinations. Missing and outlying values are substituted by model‐based estimates using all available data information. In general, the conditional inflation forecasts are consistent with the European Central Bank's assessment of liquidity conditions for future inflation prospects. The evaluation of inflation forecasts under different monetary scenarios reveals the importance of keeping track of money growth rate in particular at the end of 2005. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
7.
We report a systematic RNA interference (RNAi) screen of 5,690 Caenorhabditis elegans genes for gene inactivations that increase lifespan. We found that genes important for mitochondrial function stand out as a principal group of genes affecting C. elegans lifespan. A classical genetic screen identified a mutation in the mitochondrial leucyl-tRNA synthetase gene (lrs-2) that impaired mitochondrial function and was associated with longer-lifespan. The long-lived worms with impaired mitochondria had lower ATP content and oxygen consumption, but differential responses to free-radical and other stresses. These data suggest that the longer lifespan of C. elegans with compromised mitochrondria cannot simply be assigned to lower free radical production and suggest a more complex coupling of metabolism and longevity.  相似文献   
8.
本文根据联合国粮农组织(FAO)和国际应用系统分析研究所(IIASA)基于中国1961年以来的统计资料共同开发的AEZ模型,运用GIS平台计算了中国41个农作制亚区6大主要作物(水稻、小麦、玉米、马铃薯、油菜、大豆)的单产潜力.指出以上作物单产最高潜力分布为:水稻在江淮江汉平原,小麦在秦巴山区,玉米在黄淮平原南阳盆地,马铃薯在秦巴山区,油菜在秦巴山区,大豆在鲁西平原鲁中丘陵.研究结果表明:我国以上主要作物的最高单产潜力是目前全国平均单产的1.2-2.9倍.这对指导我国农作物高产育种及栽培具有重要参考意义.  相似文献   
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10.
Résumé La turgescence de la cellule et la plasticité de sa paroi subissent des changements après le choc; la condition de latence et la sporogénèse sont accélérées. Les organisms blessés régénèrent. Il se peut que la forme de la cellule détermine la sensibilité à la pression du choc.  相似文献   
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