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排序方式: 共有692条查询结果,搜索用时 15 毫秒
1.
Jaakko Rautiainen Seppo Auriola Anita Konttinen Tuomas Virtanen Marja Rytknen-Nissinen Thomas Zeiler Rauno Mntyjrvi 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,763(1-2)
Allergens from various sources have been shown to comprise several isoforms. In the present study, a series of chromatographic steps was carried out to separate the lipocalin allergen Bos d 2 isoforms present in cow dander. Subsequent HPLC-MS–MS analyses revealed two new Bos d 2 variants. In one of the proteins, tyrosine (Y83) was substituted by aspartic acid, and in the other protein valine (V102) was replaced by alanine. We propose the three Bos d 2 variants be named as Bos d 2.0101 (previously sequenced Bos d 2), Bos d 2.0102 and Bos d 2.0103. Our results suggest that molecular polymorphism is a common property among lipocalin allergens. Since allergen isoforms may show variation in their IgE binding and/or T-cell reactivity, all of the many allergen forms should be taken into account when planning preparations for immunotherapy. 相似文献
2.
Jyri Seppla Matti Melanen Ilmo Menp Sirkka Koskela Jyrki Tenhunen Marja‐Riitta Hiltunen 《Journal of Industrial Ecology》2005,9(4):117-130
The concept of eco-efficiency is commonly referred to as a business link to sustainable development. In this article, ecoefficiency is examined at a regional level as an approach to promoting the competitiveness of economic activities in the Finnish Kymenlaakso region and mitigating their harmful impacts on the environment. The aim is to develop appropriate indicators for monitoring changes in the eco-efficiency of the region. A starting point is to produce indicators for the environmental and economic dimensions of regional development and use them for measuring regional eco-efficiency. The environmental impact indicators are based on a life-cycle assessment method, producing different types of environmental impact indicators: pressure indicators (e.g., emissions of CO2 ), impact category indicators (e.g., CO2 equivalents in the case of climate change), and a total impact indicator (aggregating different impact category indicator results into a single value). Environmental impact indicators based on direct material input, total material input, and total material requirement of the Kymenlaakso region are also assessed. The economic indicators used are the gross domestic product, the value added, and the output of the main economic sectors of Kymenlaakso. In the eco-efficiency assessment, the economic and environmental impact indicators are monitored in the same graph. In a few cases eco-efficiency ratios can also be calculated (the economic indicators are divided by the environmental indicators). Output (= value added + intermediate consumption) is used as an economic indicator related to the environmental impact indicators, which also cover the upstream processes of the region's activities. In the article, we also discuss the strengths and weaknesses of using the different environmental impact indicators. 相似文献
3.
J. S. Uotila V. H. Kitunen T. Coote T. Saastamoinen M. Salkinoja-Salonen J. H. A. Apajalahti 《Biodegradation》1995,6(2):119-126
The actinomyceteRhodococcus chlorophenolicus PCP-1 metabolises pentachlorophenol into ultimate inorganic end products via tetrachloro-p-hydroquinone. This intermediate was further dehalogenated in the cytoplasm requiring reductant in the cell free system. Tetrafluoro-p-hydroquinone and tetrabromo-p-hydroquinone were also dehalogenated. Chlorophenol analogs, thiol blocking agents and molecular oxygen inhibited the activity. The dehalogenating reactions led to 1,2,4-trihydroxybenzene, which was further metabolized into maleic acid.Abbreviations PCP
pentachlorophenol
- TeCH
tetrachloro-p-hydroquinone
- TeFH
tetrafluoro-p-hydroquinone
- TeBH
tetrabromo-p-hydroquinone
- THB
trihydroxybenzene 相似文献
4.
Aino L. K. Liukko Tuure T. Kinnunen Marja A. Rytk?nen-Nissinen Anssi H. T. Kailaanm?ki Jukka T. Randell Bernard Maillère Tuomas I. Virtanen 《PloS one》2014,9(5)
Lipocalin allergens form a notable group of proteins, as they contain most of the significant respiratory allergens from mammals. The basis for the allergenic capacity of allergens in the lipocalin family, that is, the development of T-helper type 2 immunity against them, is still unresolved. As immunogenicity has been proposed to be a decisive feature of allergens, the purpose of this work was to examine human CD4+ T cell responses to the major dog allergen Can f 1 and to compare them with those to its human homologue, tear lipocalin (TL). For this, specific T cell lines were induced in vitro from the peripheral blood mononuclear cells of Can f 1-allergic and healthy dog dust-exposed subjects with peptides containing the immunodominant T cell epitopes of Can f 1 and the corresponding TL peptides. We found that the frequency of Can f 1 and TL-specific T cells in both subject groups was low and close to each other, the difference being about two-fold. Importantly, we found that the proliferative responses of both Can f 1 and TL-specific T cell lines from allergic subjects were stronger than those from healthy subjects, but that the strength of the responses within the subject groups did not differ between these two antigens. Moreover, the phenotype of the Can f 1 and TL-specific T cell lines, determined by cytokine production and expression of cell surface markers, resembled each other. The HLA system appeared to have a minimal role in explaining the allergenicity of Can f 1, as the allergic and healthy subjects'' HLA background did not differ, and HLA binding was very similar between Can f 1 and TL peptides. Along with existing data on lipocalin allergens, we conclude that strong antigenicity is not decisive for the allergenicity of Can f 1. 相似文献
5.
Elevated high sensitive C-reactive protein (hsCRP) is a marker for systemic inflammation and a risk marker for atherosclerotic cardiovascular disease (ACVD), and has also been associated with periodontitis. Inter-individual variation for hsCRP in periodontitis has been shown. ANRIL is the strongest genetic susceptibility locus for both periodontitis and ACVD, and it is speculated that genetic variation in ANRIL may modulate inflammatory processes. Therefore, we explored the possible association between hsCRP plasma levels and a leading ANRIL single nucleotide polymorphism (SNP) in periodontitis patients and controls. 171 healthy subjects with North European descent (115 periodontitis and 56 controls) were included in this case-control study. hsCRP levels were determined and subjects were genotyped for the leading ANRIL SNP rs1333048. In a multivariate analysis, periodontitis, female gender, increasing BMI and homozygosity for the major allele (AA-genotype) of rs1333048 were significantly associated with elevated hsCRP plasma levels (p = 0.012, p = 0.004, p = 0.007 and p = 0.003, respectively). Periodontitis patients with rs1333048 AA-genotype showed higher levels of hsCRP than those carrying the minor C allele (median: 4.5 mg/L vs. 1.6 mg/L, padjusted = 0.007). This study is the first to show that, in addition to gender and BMI, also a leading SNP in ANRIL is explanatory for inter-individual variation in hsCRP levels in periodontitis patients of North European descent. 相似文献
6.
Felicity L. Newell James Sheehan Petra Bohall Wood Amanda D. Rodewald David A. Buehler Patrick D. Keyser Jeffrey L. Larkin Tiffany A. Beachy Marja H. Bakermans Than J. Boves Andrea Evans Gregory A. George Molly E. McDermott Kelly A. Perkins Matthew B. White T. Bently Wigley 《Journal of Field Ornithology》2013,84(3):270-286
Point counts are commonly used to assess changes in bird abundance, including analytical approaches such as distance sampling that estimate density. Point‐count methods have come under increasing scrutiny because effects of detection probability and field error are difficult to quantify. For seven forest songbirds, we compared fixed‐radii counts (50 m and 100 m) and density estimates obtained from distance sampling to known numbers of birds determined by territory mapping. We applied point‐count analytic approaches to a typical forest management question and compared results to those obtained by territory mapping. We used a before–after control impact (BACI) analysis with a data set collected across seven study areas in the central Appalachians from 2006 to 2010. Using a 50‐m fixed radius, variance in error was at least 1.5 times that of the other methods, whereas a 100‐m fixed radius underestimated actual density by >3 territories per 10 ha for the most abundant species. Distance sampling improved accuracy and precision compared to fixed‐radius counts, although estimates were affected by birds counted outside 10‐ha units. In the BACI analysis, territory mapping detected an overall treatment effect for five of the seven species, and effects were generally consistent each year. In contrast, all point‐count methods failed to detect two treatment effects due to variance and error in annual estimates. Overall, our results highlight the need for adequate sample sizes to reduce variance, and skilled observers to reduce the level of error in point‐count data. Ultimately, the advantages and disadvantages of different survey methods should be considered in the context of overall study design and objectives, allowing for trade‐offs among effort, accuracy, and power to detect treatment effects. 相似文献
7.
8.
9.
Background
Research on aging has consistently demonstrated an increased chance of survival for older adults who are integrated into rich networks of social relationships. Theoretical explanations state that personal networks offer indirect psychosocial and direct physiological pathways. We investigate whether effects on and pathways to mortality risk differ between functional and structural characteristics of the personal network. The objective is to inquire which personal network characteristics are the best predictors of mortality risk after adjustment for mental, cognitive and physical health.Methods and Findings
Empirical tests were carried out by combining official register information on mortality with data from the Longitudinal Aging Study Amsterdam (LASA). The sample included 2,911 Dutch respondents aged 54 to 85 at baseline in 1992 and six follow-ups covering a time span of twenty years. Four functional characteristics (emotional and social loneliness, emotional and instrumental support) and four structural characteristics (living arrangement, contact frequency, number of contacts, number of social roles) of the personal network as well as mental, cognitive and physical health were assessed at all LASA follow-ups. Statistical analyses comprised of Cox proportional hazard regression models. Findings suggest differential effects of personal network characteristics on survival, with only small gender differences. Mortality risk was initially reduced by functional characteristics, but disappeared after full adjustment for the various health variables. Mortality risk was lowest for older adults embedded in large (HR = 0.986, 95% CI 0.979—0.994) and diverse networks (HR = 0.948, 95% CI 0.917—0.981), and this effect continued to show in the fully adjusted models.Conclusions
Functional characteristics (i.e. emotional and social loneliness) are indirectly associated with a reduction in mortality risk, while structural characteristics (i.e. number of contacts and number of social roles) have direct protective effects. More research is needed to understand the causal mechanisms underlying these relations. 相似文献10.
Antti T. Muuronen Mikko Taina Marja Hedman Jarkko Marttila Johanna Kuusisto Juha Onatsu Ritva Vanninen Pekka J?k?l? Petri Sipola Pirjo Mustonen 《PloS one》2015,10(3)