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81.
Suppression of virus load by highly active antiretroviral therapy in rhesus macaques infected with a recombinant simian immunodeficiency virus containing reverse transcriptase from human immunodeficiency virus type 1
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North TW Van Rompay KK Higgins J Matthews TB Wadford DA Pedersen NC Schinazi RF 《Journal of virology》2005,79(12):7349-7354
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Commercial forests in many parts of the world are deficient in nitrogen and phosphorus. These nutrient-deficient forests often exist in close proximity to large animal feeding operations, meat processing and other food, textile, or other biomass-processing plants, and municipal waste treatment facilities. Many of these facilities produce large surpluses of nitrogen, phosphorus, and organic matter as gaseous ammonia, urea, uric acid, phosphorus compounds, bacterial sludges, and partially treated municipal wastewaters. These co-existing and substantial nutrient deficiencies and surpluses offer ready-made opportunities for discovery, demonstration, and commercial development of science-based, technology-facilitated, environmentally sound, economically viable, and socially acceptable "win-win alliances" among these major industries based on the principles of industrial ecology and sustainable development. The major challenge is to discover practical means to capture the surplus nutrients and put them to work in forest stands from which value-added products can be produced and sold at a profit. 相似文献
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Models in which two susceptibility loci jointly influence the risk of developing disease can be explored using logistic regression analysis. Comparison of likelihoods of models incorporating different sets of disease model parameters allows inferences to be drawn regarding the nature of the joint effect of the loci. We have simulated case-control samples generated assuming different two-locus models and then analysed them using logistic regression. We show that this method is practicable and that, for the models we have used, it can be expected to allow useful inferences to be drawn from sample sizes consisting of hundreds of subjects. Interactions between loci can be explored, but interactive effects do not exactly correspond with classical definitions of epistasis. We have particularly examined the issue of the extent to which it is helpful to utilise information from a previously identified locus when investigating a second, unknown locus. We show that for some models conditional analysis can have substantially greater power while for others unconditional analysis can be more powerful. Hence we conclude that in general both conditional and unconditional analyses should be performed when searching for additional loci. 相似文献
86.
Primosome assembly protein PriA functions in the assembly of the replisome at forked DNA structures. Whereas its N-terminal DNA binding domain (DBD) binds independently to DNA, the affinity of DBD protein for forked structures is relatively weak. Although the PriA helicase domain (HD) is required for high affinity fork binding, HD protein had very low affinity for DNA. It had only low levels of ATPase activity, and it hydrolyzed ATP when DNA was absent whereas PriA did not. HD catalyzed unwinding of a minimal substrate composed of a duplex with a 3' single-stranded tail. Single-strand binding protein (SSB) bound to the tail of this substrate inhibited this reaction by full-length PriA but enhanced the reaction by HD. SSB stabilized binding of PriA but not of DBD or HD to duplexes with a 5' or 3' single-stranded tail. On forked substrates SSB enhanced helicase action on the lagging-strand arm by PriA but not by HD. The results indicate that synergy of the DBD and HD allows stable binding at the interface between duplex and single-stranded DNA bound by SSB. This mode of binding may be analogous to fork binding, which orients the helicase to act on the lagging-strand side of the fork. 相似文献
87.
Lespinasse J Réthoré MO North MO Bovier-Lapierre M Lundsteen C Fert-Ferrer S Bugge M Kirchoff M 《Annales de génétique》2004,47(3):315-324
Balanced complex chromosomal rearrangements (BCCR) encompass a heterogeneous group of rare chromosomal aberrations. In this paper, we report three cases of BCCRs. In two the probands were referred for either genetic counseling or prenatal management. One case was ascertained after chromosome analysis performed because of psychiatric manifestations; this was an isolated finding. We also outline the molecular cytogenetic techniques, which were essential in confirming and precisely delineating the BCCRs identified in these patients. In addition the various aspects of genetic counseling for this type of chromosomal rearrangement, highlighting the details particular to each individual case are discussed. We discuss the classification for this type of chromosomal mutation. 相似文献
88.
Identification of a trafficking motif involved in the stabilization and polarization of P2X receptors 总被引:7,自引:0,他引:7
Chaumont S Jiang LH Penna A North RA Rassendren F 《The Journal of biological chemistry》2004,279(28):29628-29638
Extracellular ATP-gated channels (P2X receptors) define the third major family of ionotropic receptors, and they are expressed widely in nerve cells, muscles, and endocrine and exocrine glands. P2X subunits have two membrane-spanning domains, and a receptor is thought to be formed by oligomerization of three subunits. We have identified a conserved motif in the cytoplasmic C termini of P2X subunits that is necessary for their surface expression; mutations in this motif result in a marked reduction of the receptors at the plasma membrane because of a rapid internalization. Transfer of the motif to a reporter protein (CD(4)) enhances the surface expression of the chimera, indicating that this motif is likely involved in the stabilization of P2X receptor at the cell surface. In neurons, mutated P2X(2) subunits showed reduced membrane expression and an altered axodendritic distribution. This motif is also present in intracellular regions of other membrane proteins, such as in the third intracellular loop of some G protein-coupled receptors, suggesting that it might be involve in their cellular stabilization and polarization. 相似文献
89.
Yvonne J.K. Edwards Klaudia Walter Gayle McEwen Tanya Vavouri Krystyna A. Kelly Irina Abnizova Adam Woolfe Debbie K. Goode Martin Goodson Phil North Phil Snell Heather Callaway Sarah F. Smith Walter R. Gilks Julie E. Cooke Greg Elgar 《Comparative biochemistry and physiology. Part D, Genomics & proteomics》2006,1(1):46
90.
North AJ 《The Journal of cell biology》2006,172(1):9-18
Imaging can be thought of as the most direct of experiments. You see something; you report what you see. If only things were truly this simple. Modern imaging technology has brought about a revolution in the kinds of questions we can approach, but this comes at the price of increasingly complex equipment. Moreover, in an attempt to market competing systems, the microscopes have often been inappropriately described as easy to use and suitable for near-beginners. Insufficient understanding of the experimental manipulations and equipment set-up leads to the introduction of errors during image acquisition. In this feature, I review some of the most common practical pitfalls faced by researchers during image acquisition, and how they can affect the interpretation of the experimental data.This article is targeted neither to the microscopy gurus who push forward the frontiers of imaging technology nor to my imaging specialist colleagues who may wince at the overly simplistic comments and lack of detail. Instead, this is for beginners who gulp with alarm when they hear the word "confocal pinhole" or sigh as they watch their cells fade and die in front of their very eyes time and time again at the microscope. Take heart, beginners, if microscopes were actually so simple then many people (including myself) would suddenly be out of a job! 相似文献