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Memories become stabilized through a time-dependent process that requires gene expression and is commonly known as consolidation. During this time, memories are labile and can be disrupted by a number of interfering events, including electroconvulsive shock, trauma and other learning or the transient effect of drugs such as protein synthesis inhibitors. Once consolidated, memories are insensitive to these disruptions. However, they can again become fragile if recalled or reactivated. Reactivation creates another time-dependent process, known as reconsolidation, during which the memory is restabilized. Here we discuss some of the questions currently debated in the field of memory consolidation and reconsolidation, the molecular and anatomical requirements for both processes and, finally, their functional relationship. 相似文献
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Recent experience with several high-profile drugs demonstrates the great challenges in developing effective and safe therapeutics. A complementary approach to the popular paradigm of disease genetics is based on inherited factors that reduce the incidence and severity of disease among individuals who are genetically predisposed to disease. We propose testing specifically for modifier genes and protective alleles among at-risk individuals and studying the efficacy of therapeutics based on the genetics of health. 相似文献
427.
Common variation in three genes, including a noncoding variant in CFH, strongly influences risk of age-related macular degeneration 总被引:12,自引:0,他引:12
Maller J George S Purcell S Fagerness J Altshuler D Daly MJ Seddon JM 《Nature genetics》2006,38(9):1055-1059
Age-related macular degeneration (AMD) is a common, late-onset disease with seemingly typical complexity: recurrence ratios for siblings of an affected individual are three- to sixfold higher than in the general population, and family-based analysis has resulted in only modestly significant evidence for linkage. In a case-control study drawn from a US-based population of European descent, we have identified a previously unrecognized common, noncoding variant in CFH, the gene encoding complement factor H, that substantially increases the influence of this locus on AMD, and we have strongly replicated the associations of four other previously reported common alleles in three genes (P values ranging from 10(-6) to 10(-70)). Despite excellent power to detect epistasis, we observed purely additive accumulation of risk from alleles at these genes. We found no differences in association of these loci with major phenotypic categories of advanced AMD. Genotypes at these five common SNPs define a broad spectrum of interindividual disease risk and explain about half of the classical sibling risk of AMD in our study population. 相似文献
428.
The mammalian olfactory system is not uniformly organized but consists of several subsystems each of which probably serves
distinct functions. Not only are the two major nasal chemosensory systems, the vomeronasal organ and the main olfactory epithelium,
structurally and functionally separate entities, but the latter is further subcompartimentalized into overlapping expression
zones and projection-related subzones. Moreover, the populations of ‘OR37’ neurons not only express a unique type of olfactory
receptors but also are segregated in a cluster-like manner and generally project to only one receptor-specific glomerulus.
The septal organ is an island of sensory epithelium on the nasal septum positioned at the nasoplatine duct; it is considered
as a ‘mini-nose’ with dual function. A specific chemosensory function of the most recently discovered subsystem, the so-called
Grueneberg ganglion, is based on the expression of olfactory marker protein and the axonal projections to defined glomeruli
within the olfactory bulb. This complexity of distinct olfactory subsystems may be one of the features determining the enormous
chemosensory capacity of the sense of smell. 相似文献
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Relation between total and exchangeable sodium in the body 总被引:1,自引:0,他引:1