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排序方式: 共有451条查询结果,搜索用时 62 毫秒
101.
Maria Paola Paronetto Valeria Messina Enrica Bianchi Marco Barchi Gillian Vogel Costanzo Moretti Fioretta Palombi Mario Stefanini Raffaele Geremia Stéphane Richard Claudio Sette 《The Journal of cell biology》2009,185(2):235-249
Sam68 is a KH-type RNA-binding protein involved in several steps of RNA metabolism with potential implications in cell differentiation and cancer. However, its physiological roles are still poorly understood. Herein, we show that Sam68−/− male mice are infertile and display several defects in spermatogenesis, demonstrating an essential role for Sam68 in male fertility. Sam68−/− mice produce few spermatozoa, which display dramatic motility defects and are unable to fertilize eggs. Expression of a subset of messenger mRNAs (mRNAs) is affected in the testis of knockout mice. Interestingly, Sam68 is associated with polyadenylated mRNAs in the cytoplasm during the meiotic divisions and in round spermatids, when it interacts with the translational machinery. We show that Sam68 is required for polysomal recruitment of specific mRNAs and for accumulation of the corresponding proteins in germ cells and in a heterologous system. These observations demonstrate a novel role for Sam68 in mRNA translation and highlight its essential requirement for the development of a functional male gamete. 相似文献
102.
103.
Rembert Koczulla Silvano Dragonieri Robert Schot Robert Bals Stefanie A Gauw Claus Vogelmeier Klaus F Rabe Peter J Sterk Pieter S Hiemstra 《Respiratory research》2009,10(1):78
Background
Analysis of exhaled breath condensate (EBC) is a non-invasive method for studying the acidity (pH) of airway secretions in patients with inflammatory lung diseases.Aim
To assess the reproducibility of EBC pH for two commercially available devices (portable RTube and non-portable ECoScreen) in healthy controls, patients with asthma or COPD, and subjects suffering from an acute cold with lower-airway symptoms. In addition, we assessed the repeatability in healthy controls.Methods
EBC was collected from 40 subjects (n = 10 in each of the above groups) using RTube and ECoScreen. EBC was collected from controls on two separate occasions within 5 days. pH in EBC was assessed after degasification with argon for 20 min.Results
In controls, pH-measurements in EBC collected by RTube or ECoScreen showed no significant difference between devices (p = 0.754) or between days (repeatability coefficient RTube: 0.47; ECoScreen: 0.42) of collection. A comparison between EBC pH collected by the two devices in asthma, COPD and cold patients also showed good reproducibility. No differences in pH values were observed between controls (mean pH 8.27; RTube) and patients with COPD (pH 7.97) or asthma (pH 8.20), but lower values were found using both devices in patients with a cold (pH 7.56; RTube, p < 0.01; ECoScreen, p < 0.05).Conclusion
We conclude that pH measurements in EBC collected by RTube and ECoScreen are repeatable and reproducible in healthy controls, and are reproducible and comparable in healthy controls, COPD and asthma patients, and subjects with a common cold. 相似文献104.
105.
Rossini M Maddali Bongi S La Montagna G Minisola G Malavolta N Bernini L Cacace E Sinigaglia L Di Munno O Adami S 《Arthritis research & therapy》2010,12(6):R216
Introduction
The aim of this study was to estimate the prevalence and determinants of vitamin D deficiency in patients with rheumatoid arthritis (RA) as compared to healthy controls and to analyze the association between 25-hydroxyvitamin D (25(OH)D) with disease activity and disability. 相似文献106.
Martínez-Sánchez JM Fernández E Fu M Gallus S Martínez C Sureda X La Vecchia C Clancy L 《PloS one》2010,5(11):e13881
Background
The six most important cost-effective policies on tobacco control can be measured by the Tobacco Control Scale (TCS). The objective of our study was to describe the correlation between the TCS and smoking prevalence, self-reported exposure to secondhand smoke (SHS) and attitudes towards smoking restrictions in the 27 countries of the European Union (EU27).Methods/Principal Findings
Ecologic study in the EU27. We used data from the TCS in 2007 and from the Eurobarometer on Tobacco Survey in 2008. We analysed the relations between the TCS and prevalence of smoking, self-reported exposure to SHS (home and work), and attitudes towards smoking bans by means of scatter plots and Spearman rank-correlation coefficients (rsp). Among the EU27, smoking prevalence varied from 22.6% in Slovenia to 42.1% in Greece. Austria was the country with the lowest TCS score (35) and the UK had the highest one (93). The correlation between smoking prevalence and TCS score was negative (rsp = −0.42, p = 0.03) and the correlation between TCS score and support to smoking bans in all workplaces was positive (rsp = 0.47, p = 0.01 in restaurants; rsp = 0.5, p = 0.008 in bars, pubs, and clubs; and rsp = 0.31, p = 0.12 in other indoor workplaces). The correlation between TCS score and self-reported exposure to SHS was negative, but statistically non-significant.Conclusions/Significance
Countries with a higher score in the TCS have higher support towards smoking bans in all workplaces (including restaurants, bars, pubs and clubs, and other indoor workplaces). TCS scores were strongly, but not statistically, associated with a lower prevalence of smokers and a lower self-reported exposure to SHS. 相似文献107.
108.
Spugnini EP Bosari S Citro G Lorenzon I Cognetti F Baldi A 《The international journal of biochemistry & cell biology》2006,38(12):2000-2004
The continuing identification and elucidation of the molecular defects involved in mesothelioma pathogenesis and progression should lead to better disease control and greater therapeutic options in the near future. Goal of this review article is to summarize the most recent advances in molecular pathogenesis of mesothelioma and discuss possible therapeutic implications of these findings. 相似文献
109.
Bettler E Samain E Chazalet V Bosso C Heyraud A Joziasse DH Wakarchuk WW Imberty A Geremia AR 《Glycoconjugate journal》1999,16(3):205-212
Scientific and commercial interest in oligosaccharides is increasing, but their availability is limited as production relies on chemical or chemo-enzymatic synthesis. In search for a more economical, alternative procedure, we have investigated the possibility of producing specific oligosaccharides in E. coli that express the appropriate glycosyltransferases. The Azorhizobium chitin pentaose synthase NodC (a (1,4)GlcNAc-transferase), and the Neisseria (1,4)galactosyltransferase LgtB, were co-expressed in E. coli. The major oligosaccharide isolated from the recombinant strain, was subjected to LC-MS, FAB-MS and NMR analysis, and identified as Gal(1,4)[GlcNAc(1,4)]4GlcNAc. High cell density culture yielded more than 1.0 gr of the hexasaccharide per liter of culture. The compound was found to be an acceptor in vitro for Gal(1,4)GlcNAc (1,3)galactosyltransferase, which suggests that the expression of additional glycosyltransferases in E. coli will allow the production of more complex oligosaccharides. 相似文献
110.
TT virus in the nasal secretions of children with acute respiratory diseases: relations to viremia and disease severity 总被引:4,自引:0,他引:4
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Maggi F Pifferi M Fornai C Andreoli E Tempestini E Vatteroni M Presciuttini S Marchi S Pietrobelli A Boner A Pistello M Bendinelli M 《Journal of virology》2003,77(4):2418-2425
The natural history and pathogenic potential of the recently identified TT virus (TTV) are currently a matter of intensive investigation. In an attempt to shed some light on these issues, nasal and blood specimens of 1- to 24-month-old children hospitalized with a clinical diagnosis of acute respiratory disease (ARD) were examined for the presence, load, and genetic characteristics of TTV. The results have indicated that at least in young children, the respiratory tract not only represents a route by which abundant TTV can be shed into the environment but also may be a site of primary infection and continual replication. Although we found no compelling evidence that TTV was the direct cause of ARD in some of the children studied, the average loads of TTV were considerably higher in patients with bronchopneumonia (BP) than in those with milder ARD, raising interesting questions about the pathophysiological significance of TTV at this site. Furthermore, group 4 TTV was detected almost exclusively in children with BP. 相似文献