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131.
Abstract The chemical compositions of a number of halophytes from salt marshes on Ynys Môn (Anglesey), Wales, and of some related mesophytes and sand dune plants have been determined. Analyses of the inorganic ions broadly confirmed the existence of a characteristic chemical composition of many monoco-tyledonous salt-marsh plants in that they contain high levels of potassium and relatively low levels of sodium. In contrast to most dicotyledonous halophytes, especially members of the Chenopodiacease, the monocots restrict the entry of inorganic ions and use high levels of soluble sugars to maintain an adequate solute potential. Low calcium levels were not found to be a feature of these plants, as was previously reported. The large amounts of sugars found in the monocotyle-donous plants suggested that they must be located mainly in the vacuoles, in contrast to glycinebetaine which is thought to accumulate principally in the cytoplasm of the salt accumulating Chenopodiaceae. The monocotyledonous halophytes which accumulate proline differ from the normal monocotyledonous physiotype in the accumulation of larger quantities of sodium. Triglochin maritima is one species of this type, and Puccinellia maritima a less extreme example. Spartina spp. accumulating glycinebetaine and β-dimethyl-sulphoniopropionate also have unusually high inorganic ion contents for monocots. Several salt marsh plants contained large quantities of amino acids other than proline. As with ionic composition, the nature of the organic solutes broadly followed taxonomic lines. The usefulness of the physiotype concept is discussed.  相似文献   
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Background

Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis in infants. Following RSV bronchiolitis, 50% of children develop post-bronchiolitis wheeze (PBW). Animal studies have suggested that interleukin (IL)-10 plays a critical role in the pathogenesis of RSV bronchiolitis and subsequent airway hyperresponsiveness. Previously, we showed that ex vivo monocyte IL-10 production is a predictor of PBW. Additionally, heterozygosity of the single-nucleotide polymorphism (SNP) rs1800872 in the IL10 promoter region was associated with protection against RSV bronchiolitis.

Methods

This study aimed to determine the in vivo role of IL-10 in RSV pathogenesis and recurrent wheeze in a new cohort of 235 infants hospitalized for RSV bronchiolitis. IL-10 levels in nasopharyngeal aspirates (NPAs) were measured at the time of hospitalization and the IL10 SNP rs1800872 genotype was determined. Follow-up data were available for 185 children (79%).

Results

Local IL-10 levels during RSV infection turned out to be higher in infants that later developed physician diagnosed PBW as compared to infants without PBW in the first year after RSV infection (958 vs 692 pg/ml, p = 0.02). The IL10 promoter SNP rs1800872 was not associated with IL-10 concentration in NPAs.

Conclusion

The relationship between high local IL-10 levels during the initial RSV infection and physician diagnosed PBW provides further evidence of the importance of the IL-10 response during RSV bronchiolitis.  相似文献   
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Background  

The alignment of multiple protein sequences is a fundamental step in the analysis of biological data. It has traditionally been applied to analyzing protein families for conserved motifs, phylogeny, structural properties, and to improve sensitivity in homology searching. The availability of complete genome sequences has increased the demands on multiple sequence alignment (MSA) programs. Current MSA methods suffer from being either too inaccurate or too computationally expensive to be applied effectively in large-scale comparative genomics.  相似文献   
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This article clarifies the regulatory issues surrounding influenza pandemic vaccine for the larger policy community and describes the need for regulatory harmonization. Vaccination would save lives in an influenza pandemic, but a lack of global manufacturing capacity will leave most of the world without access to vaccine. Capacity can be expanded if governments harmonize their regulatory policies. This article details the regulatory approaches taken by the United States, the European Union, and Japan for pandemic vaccine development, three regions that produce the majority of the world's seasonal influenza vaccine. They should quickly converge on regulatory requirements, intellectual property considerations, the use of recombinant DNA techniques for vaccine production, and technical issues about the composition of pandemic vaccine.  相似文献   
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Background  

Chronic Fatigue Syndrome (CFS) is increasingly recognized as a cause of disability and inactivity in adolescents in the Netherlands. CFS is characterized by unexplained fatigue lasting more than 6 months. Cognitive Behavioural Therapy (CBT) has proven to be effective. However, CBT availability for adolescents with CFS is limited and requires special therapeutic skills not always readily available. An alternative to the face-to-face CBT is FITNET, a web-based therapeutic program designed specifically for adolescents diagnosed with CFS, and their parents. This new CBT approach appeals to the modern youth, who grow up with internet as their main source of information. A web-based program offers the opportunity to lower thresholds for the acceptance and realization of healthcare. This treatment can be activated at any chosen time. The communication between patient and therapist can elapse asynchronously. If effective, this web-based program would greatly increase the therapeutic accessibility.  相似文献   
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