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排序方式: 共有196条查询结果,搜索用时 46 毫秒
101.
Margot ME Gosman Dirkje S Postma Judith M Vonk Bea Rutgers Monique Lodewijk Mieke Smith Marjan A Luinge Nick HT ten Hacken Wim Timens 《Respiratory research》2008,9(1):1-9
Background
Surfactant protein D (SP-D), an innate immune molecule, plays an important protective role during airway inflammation. Deficiency of this molecule induces emphysematous changes in murine lungs, but its significance in human COPD remains unclear.Methods
We collected bronchoalveolar lavage fluid from 20 subjects with varying degrees of COPD (8 former smokers and 12 current smokers) and 15 asymptomatic healthy control subjects (5 never smokers, 3 remote former smokers, and 7 current smokers). All subjects underwent a complete medical history and pulmonary function testing. SP-D was measured by Enzyme-Linked ImmunoSorbent Assay. Statistical analysis was performed using nonparametric methods and multivariable linear regression for control of confounding. The effect of corticosteroid treatment on SP-D synthesis was studied in vitro using an established model of isolated type II alveolar epithelial cell culture.Results
Among former smokers, those with COPD had significantly lower SP-D levels than healthy subjects (median 502 and 1067 ng/mL, respectively, p = 0.01). In a multivariable linear regression model controlling for age, sex, race, and pack-years of tobacco, COPD was independently associated with lower SP-D levels (model coefficient -539, p = 0.04) and inhaled corticosteroid use was independently associated with higher SP-D levels (398, p = 0.046). To support the hypothesis that corticosteroids increase SP-D production we used type II alveolar epithelial cells isolated from adult rat lungs. These cells responded to dexamethasone treatment by a significant increase of SP-D mRNA (p = 0.041) and protein (p = 0.037) production after 4 days of culture.Conclusion
Among former smokers, COPD is associated with lower levels of SP-D and inhaled corticosteroid use is associated with higher levels of SP-D in the lung. Dexamethasone induced SP-D mRNA and protein expression in isolated epithelial cells in vitro. Given the importance of this molecule as a modulator of innate immunity and inflammation in the lung, low levels may play a role in the pathogenesis and/or progression of COPD. Further, we speculate that inhaled steroids may induce SP-D expression and that this mechanism may contribute to their beneficial effects in COPD. Larger, prospective studies are warranted to further elucidate the role of surfactant protein D in modulating pulmonary inflammation and COPD pathogenesis. 相似文献102.
1998年5月-2000年10月间调查了梅州柚果贮藏期的真菌病害,它们是:①柚果绿霉病(Penicilliumdigitatum),②柚果炭疽病(Collettrichumgloeosporioides),③柚果黑腐病(Alternariacitri),④柚果焦腐病(Diplodianatalensis)和⑤柚果酸腐病(Oosporacitri-aurantii)等5种.从几种安全性高的保鲜剂中筛选出1个混用配方,该配方对柚果贮藏防腐保鲜效果明显,贮藏5个月无病斑果达100%,6个月也只有20%的柚果出现少量病斑,且柚果几项质量指标较好. 相似文献
103.
Liver-specific and seasonal expression of transgenic Atlantic salmon harboring the winter flounder antifreeze protein gene 总被引:4,自引:1,他引:3
Hew C Poon R Xiong F Gauthier S Shears M King M Davies P Fletcher G 《Transgenic research》1999,8(6):405-414
We have analyzed the inheritance and expression of a line of transgenic salmon harboring the antifreeze protein gene from the winter flounder. The genomic clone 2A-7 coding for a major liver-type antifreeze protein gene (wflAFP-6) was integrated into the salmon genome. From a transgenic founder (# 1469), an F3 generation was produced. In this study, southern blot analysis showed that only one copy of the antifreeze protein transgene was integrated into a unique site in F3 transgenic fish. The integration site was cloned and characterized. Northern analysis indicated that the antifreeze protein mRNA was only expressed in the liver and showed seasonal variation. All of the F3 offspring contained similar levels of the antifreeze protein precursor protein in the sera and the sera of these offspring showed a characteristic hexagonal ice crystal pattern indicating the presence of antifreeze activity. In addition, the antifreeze protein precursor protein level was found to vary with the season, being highest in the month of November and lowest in May. This study had demonstrated a tissue-specific and stable expression of the antifreeze protein transgene in the F3 generation of the transgenic salmon 1469 line. 相似文献
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107.
RAFAEL G. SEVILLA AMALIA DIEZ MICHAEL NORN OLIVIER MOUCHEL MARC JR
ME VRONIQUE VERREZ‐BAGNIS HILDE VAN PELT LAURENCE FAVRE‐KREY GRIGORIOS KREY THE FISHTRACE CONSORTIUM JOS M. BAUTISTA 《Molecular ecology resources》2007,7(5):730-734
This report describes a set of 21 polymerase chain reaction primers and amplification conditions developed to barcode practically any teleost fish species according to their mitochondrial cytochrome b and nuclear rhodopsin gene sequences. The method was successfully tested in more than 200 marine fish species comprising the main Actinopterygii family groups. When used in phylogenetic analyses, its combination of two genes with different evolutionary rates serves to identify fish at the species level. We provide a flow diagram indicating our validated polymerase chain reaction amplification conditions for barcoding and species identification applications as well as population structure or haplotyping analyses, adaptable to high‐throughput analyses. 相似文献
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109.
Daniele Aureli Antonio Contardi Biagio Giaccio Brian Jicha Cristina Lemorini Sergio Madonna Donatella Magri Federica Marano Salvatore Milli Valerio Modesti Maria Rita Palombo Roxane Rocca 《PloS one》2015,10(4)
The Ficoncella site in northern Latium (Italy) represents a unique opportunity to investigate the modalities of a short occupation in an alluvial setting during the Lower Palaeolithic. The small excavation area yielded a lithic assemblage, a carcass of Palaeoloxodon antiquus, and some other faunal remains. The main objectives of the study are to better characterize the depositional context where the Palaeoloxodon and the lithic assemblage occur, and to evaluate with greater precision the occupation dynamics. A 25 m-long well was drilled just above the top of the terrace of the Ficoncella site and faunal and lithic remains were analyzed with current and innovative techniques. The archaeological site contains floodplain deposits as it is located next to a small incised valley that feeds into a larger valley of the Mignone River. A tephra layer capping the site is 40Ar/39Ar dated to 441± 8 ka. Collectively, the geochronologic, tephrochronologic and geologic data, suggest the site was occupied during MIS 13. The new results should prompt further research at Ficoncella in order to improve our understanding of the dynamics of human settlement in Europe during the Early to Middle Pleistocene. 相似文献
110.