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Comparative genomics: Insecticide resistance in mosquito vectors 总被引:8,自引:0,他引:8
Weill M Lutfalla G Mogensen K Chandre F Berthomieu A Berticat C Pasteur N Philips A Fort P Raymond M 《Nature》2003,423(6936):136-137
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S. R. Philips G. B. Baker H. R. McKim 《Cellular and molecular life sciences : CMLS》1980,36(2):241-242
Summary Concentrations of 4 trace amines in diencephalon and hippocampus of the rat were measured by integrated-ioncurrent mass spectrometry after administration of the antidepressant drug, tranylcypromine. Much larger increases were observed for 2-phenylethylamine and tryptamine than for m- and p-tyramine.Financial support has been provided by the Medical Research Council of Canada, the Psychiatric Services Branch, Province of Saskatchewan, the Alberta Mental health Research Fund, and the Special Services and Research Committee, University of Alberta Hospital.Acknowledgments. The authors wish to thank Dr B.A. Davis for synthesizing the deuterated internal standards and Dr D.A. Durden for supervising the mass spectral analyses. Expert technical assistance was provided by Mr R.C. Mag-Atas and Ms D.G. Calverley. The advice and encouragement of Professors W. G. Dewhurst and A. A. Boulton are gratefully acknowledged. 相似文献
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Thomas Khler Tobias Klinder Udo van Stevendaal Cristian Lorenz Peter Forthmann 《清华大学学报》2010,15(1):87-95
This paper investigates a reconstruction method for helical computed tomography which compensates for the motion artifacts in the thorax caused by patient breathing.The method takes into account a motion vector field determined from a four-dimensional(4-D) uncompensated image data set.Surface models of the lung and the ribs are tracked through the 4-D data set to create motion information within the entire thorax.Finally,an image is reconstructed using motion compensated back-projection.The results show tha... 相似文献
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RNA processing and human disease 总被引:9,自引:0,他引:9
Gene expression involves multiple regulated steps leading from gene to active protein. Many of these steps involve some aspect of RNA processing. Diseases caused by mutations that directly affect RNA processing are relatively rare compared with mutations that disrupt protein function. The vast majority of diseases of RNA processing result from loss of function of a single gene due to mutations in cis-acting elements required for pre-messenger RNA (mRNA) splicing. However, a few diseases are caused by alterations in the trans-acting factors required for RNA processing and in the vast majority of cases it is the pre-mRNA splicing machinery that is affected. Clearly, alterations that disrupt splicing of pre-mRNAs from large numbers of genes would be lethal at the cellular level. A common theme among these diseases is that only subsets of genes are affected. This is consistent with an emerging view that different subsets of exons require different sets of cis-acting elements and trans-acting factors. 相似文献
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低碳锰钢中周期性带状组织 总被引:6,自引:0,他引:6
用扫描电镜和电子探针研究了低碳锰钢中的周期性带状组织,结果表明,在全部研究用钢中,钢锭经热轧后均出现这种组织,其严重程度随钢的成分而异,并随坯带加工顺序而增加,带状组织与锰的显微偏析等因素有关,适当的调整碳锰以及形成模跨铁素体带的转变产物可降低带状组织的严重程度。 相似文献
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Aberrant regulation of insulin receptor alternative splicing is associated with insulin resistance in myotonic dystrophy 总被引:11,自引:0,他引:11
Agouti protein, a paracrine signaling molecule normally limited to skin, is ectopically expressed in lethal yellow (A(y)) mice, and causes obesity by mimicking agouti-related protein (Agrp), found primarily in the hypothalamus. Mouse attractin (Atrn) is a widely expressed transmembrane protein whose loss of function in mahogany (Atrn(mg-3J)/ Atrn(mg-3J)) mutant mice blocks the pleiotropic effects of A(y). Here we demonstrate in transgenic, biochemical and genetic-interaction experiments that attractin is a low-affinity receptor for agouti protein, but not Agrp, in vitro and in vivo. Additional histopathologic abnormalities in Atrn(mg-3J)/Atrn(mg-3J) mice and cross-species genomic comparisons indicate that Atrn has multiple functions distinct from both a physiologic and an evolutionary perspective. 相似文献
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B. Tabakoff Frances Moses S. R. Philips A. A. Boulton 《Cellular and molecular life sciences : CMLS》1977,33(3):380-381
Summary Tranylcypromine produces behavioral excitation while pargyline produces depression. Tranylcypromine increased brain tryptophan which led to an accumulation of tryptamine. The levels of tryptamine after tranylcypromine were found to be 3 times those found after pargyline.This work was supported in part by U. S. Public Health Service Grants NS-12759 and AA-2696, State of Illinois Department of Mental Health, the Psychiatric Services Branch, Province of Saskatchewan, and the Medical Research Council of Canada, who have provided continuing financial support.Acknowledgments. We thank Dr B. A. Davis for synthesizing the deuterated internal standards, Dr D. A. Durden for supervising the mass spectrometric analyses, and Mr H. Miyashita, Mr N. F. Binder and Miss E. E. Johnson for skilled technical assistance. 相似文献
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为了研究东南印度洋海域冬季水文特征及其水团结构,利用澳大利亚海洋与南极研究所2012-2013年南半球冬季在东南印度洋观测得到的温度、盐度和溶解氧的资料进行分析。结果表明:表层温度呈现明显的北高南低态势,次表层均存在较强的温度、盐度、密度跃层,且均呈现出高/低盐带与高/低溶解氧带,高盐带在经向断面上最为明显;在105°E断面上存在显著的中尺度现象,且呈现上下层暖、冷涡叠置的分布特征,根据温度、盐度及溶解氧的特性,除南印度洋中央水和南极中层水外,分别将研究海域其他水团命名为副热带东南印度洋表层水、副热带东南印度洋次表层水、副热带东南印度洋模态水、副热带东南印度洋中层水、副热带东南印度洋深层水和副热带东南印度洋底层水,并给出各自的特性指标。 相似文献
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Bivona TG Pérez De Castro I Ahearn IM Grana TM Chiu VK Lockyer PJ Cullen PJ Pellicer A Cox AD Philips MR 《Nature》2003,424(6949):694-698
Ras proteins regulate cellular growth and differentiation, and are mutated in 30% of cancers. We have shown recently that Ras is activated on and transmits signals from the Golgi apparatus as well as the plasma membrane but the mechanism of compartmentalized signalling was not determined. Here we show that, in response to Src-dependent activation of phospholipase Cgamma1, the Ras guanine nucleotide exchange factor RasGRP1 translocated to the Golgi where it activated Ras. Whereas Ca(2+) positively regulated Ras on the Golgi apparatus through RasGRP1, the same second messenger negatively regulated Ras on the plasma membrane by means of the Ras GTPase-activating protein CAPRI. Ras activation after T-cell receptor stimulation in Jurkat cells, rich in RasGRP1, was limited to the Golgi apparatus through the action of CAPRI, demonstrating unambiguously a physiological role for Ras on Golgi. Activation of Ras on Golgi also induced differentiation of PC12 cells, transformed fibroblasts and mediated radioresistance. Thus, activation of Ras on Golgi has important biological consequences and proceeds through a pathway distinct from the one that activates Ras on the plasma membrane. 相似文献
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Kevin M. O Neill William P. Kemp Catherine Seibert Marni G. Rolston James A. Bess T. Keith Philips 《西北部美国博物学家》2011,61(2)
We conducted a 2-year survey, using sweep sampling and family-level taxon identification, of the predatory and parasitoid insects on grassland sites in the Gallatin Valley of southwestern Montana. The 25 sites were divided into 4 habitat classes: 2 native habitat types ( Stipa comata/Bouteloua gracilis and Festuca idahoensis/Agropyron spicatum ) and 2 that had been reseeded with either crested wheatgrass ( Agropyron cristatum ) or smooth brome ( Bromus inermis ). Our major goal was to make quantitative comparisons of the abundance of insects among native and reseeded habitats. Of 51 families in 5 insect orders identified, 7 Hymenoptera (Encyrtidae, Braconidae, Ichneumonidae, Pteromalidae, Eulophidae, Scelionidae, and Torymidae), 3 Hemiptera (Lygaeidae, Nabidae, and Reduviidae), 1 Coleoptera (Coccinellidae), and 1 Diptera (Asilidae) comprised 90% of the natural enemies sampled. Ordination analyses provided no strong evidence that the 4 habitat classes contained distinct overall natural enemy communities. However, contiguous native and reseeded sites usually had relatively different overall natural enemy assemblages, suggesting that vegetation was often a more important correlate of community composition than was close spatial proximity of sites. Furthermore, several common families exhibited differential abundances across habitat classes in one or both years. For example, in 1989, Eulophidae, Pteromalidae, and Torymidae were more abundant on native Festuca/Agropyron sites, whereas Encyrtidae and Nabidae were more abundant on Festuca/Agropyron sites reseeded with Bromus inermis . Although analyses of insect assemblages classified to the family level provide somewhat limited information on functional ecological differences among habitats, they allow one to survey a broad array of taxa to identify focal groups for future conservation and land management studies. 相似文献
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