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101.
Apoptosis and airway inflammation in asthma   总被引:2,自引:0,他引:2  
Asthma is a disease characterized by a chronic inflammation of the airways and by structural alterations of bron-chial tissues, often referred to as airway remodelling. The development of chronic airway inflammation in asthma depends upon the continuous recruitment of inflammatory cells from the bloodstream towards the bronchial mucosa and by their subsequent activation. It is however increasingly accepted that mechanisms involved in the regulation of the survival and apoptosis of inflammatory cells may play a central role in the persistent inflammatory process characterizing this disease. Increased cellular recruitment and activation, enhanced cell survival and cell:cell interactions are therefore the key steps in the development of chronic airway inflammation in asthma, and represent the major causes for tissue damge, repair and remodelling.  相似文献   
102.
Four individual linkage maps were constructed from two crosses for the species complex Picea mariana (Mill.) B.S.P. × Picea rubens Sarg in order to integrate their information into a composite map and to compare with other Pinaceae. For all individual linkage maps, 12 major linkage groups were recovered with 306 markers per map on average. Before building the composite linkage map, the common male parent between the two crosses made it possible to construct a reference linkage map to validate the relative position of homologous markers. The final composite map had a length of 2,319 cM (Haldane) and contained a total of 1,124 positioned markers, including 1,014 AFLPs, 3 RAPDs, 53 SSRs, and 54 ESTPs, assembled into 12 major linkage groups. Marker density of the composite map was statistically homogenous and was much higher (one marker every 2.1 cM) than that of the individual linkage maps (one marker every 5.7 to 7.1 cM). Synteny was well conserved between individual, reference, and composite linkage maps and 94% of homologous markers were colinear between the reference and composite maps. The combined information from the two crosses increased by about 24% the number of anchor markers compared to the information from any single cross. With a total number of 107 anchor markers (SSRs and ESTPs), the composite linkage map is a useful starting point for large-scale genome comparisons at the intergeneric level in the Pinaceae. Comparisons of this map with those in Pinus and Pseudotsuga allowed the identification of one breakdown in synteny where one linkage group homoeologous to both Picea and Pinus corresponded to two linkage groups in Pseudotsuga. Implications for the evolution of the Pinaceae genome are discussed. Electronic Supplementary Material Supplementary material is available for this article at  相似文献   
103.
In aquaculture, microsatellite DNA markers are used to genotype parental broodstock, to assess fertilization success, and to maintain pedigree information for selective breeding. In this study we genotyped individual Haliotis asinina larvae by analyzing a suit of polymorphic microsatellite loci. At least 10 loci can be analyzed from a single abalone veliger larva. We assayed 5 polymorphic loci to identify the parents of individual larvae produced in 3 separate crosses. In all cases, the parents of an individual veliger could be determined from as few as 3 loci. The microsatellite analysis revealed that, in each of our crosses, a single male fathered most of the veligers, despite efforts to normalize the amount of sperm contributed by competing males. These observations suggest that highly controlled breeding practices may be required to ensure that the genetic diversity of an abalone population produced for aquaculture is maintained at the level of diversity of the original broodstock. Received December 4, 2000; accepted May 22, 2001.  相似文献   
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Genetic means for height growth differed between intra- and inter-provenance crosses, which we hypothesized was due partly to unidentified relatedness among intra-provenance base parents resulting in mild inbreeding and inbreeding depression among their offspring. A dense array of 5,844 single nucleotide polymorphisms was used to directly construct a genomic relationship matrix (G) that had four elements ranging from 0.17 to 0.24, between five intra-provenance base parents. Adjusting the numerator relationship matrix for this relatedness among base parents produced inbreeding coefficients of F i ≈ 0.1 in their offspring, which displayed depressed height growth. Accounting for inbreeding level as a covariate in a mixed model decreased grossly overestimated (up to 2 ×) dominance variance in models without the covariate adjustment. Height growth decreased 39 cm (~ 6 %) for every 0.1 increase in F i .  相似文献   
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We report the synthesis and biological evaluation of 5-substituted 1,4-dihydroindeno[1,2-c]pyrazoles as multitargeted kinase inhibitors. Initial efforts focused on the development of selective KDR inhibitors, while later strategies involved the improvement of potency toward multiple kinase targets. Thus, several compounds were identified as potent KDR, Flt1, Flt3, and c-Kit inhibitors.  相似文献   
109.
The ongoing development of the Global Carbon Project (GCP) global methane (CH4) budget shows a continuation of increasing CH4 emissions and CH4 accumulation in the atmosphere during 2000–2017. Here, we decompose the global budget into 19 regions (18 land and 1 oceanic) and five key source sectors to spatially attribute the observed global trends. A comparison of top-down (TD) (atmospheric and transport model-based) and bottom-up (BU) (inventory- and process model-based) CH4 emission estimates demonstrates robust temporal trends with CH4 emissions increasing in 16 of the 19 regions. Five regions—China, Southeast Asia, USA, South Asia, and Brazil—account for >40% of the global total emissions (their anthropogenic and natural sources together totaling >270 Tg CH4 yr?1 in 2008–2017). Two of these regions, China and South Asia, emit predominantly anthropogenic emissions (>75%) and together emit more than 25% of global anthropogenic emissions. China and the Middle East show the largest increases in total emission rates over the 2000 to 2017 period with regional emissions increasing by >20%. In contrast, Europe and Korea and Japan show a steady decline in CH4 emission rates, with total emissions decreasing by ~10% between 2000 and 2017. Coal mining, waste (predominantly solid waste disposal) and livestock (especially enteric fermentation) are dominant drivers of observed emissions increases while declines appear driven by a combination of waste and fossil emission reductions. As such, together these sectors present the greatest risks of further increasing the atmospheric CH4 burden and the greatest opportunities for greenhouse gas abatement.  相似文献   
110.
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