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1.
Daniel A. Truchado Michaël A. J. Moens Sergio Callejas Javier Pérez-Tris Laura Benítez 《Veterinary research communications》2018,42(2):111-120
Papillomaviruses are non-enveloped, DNA viruses that infect skin and mucosa of a wide variety of vertebrates, causing neoplasias or simply persisting asymptomatically. Avian papillomaviruses, with six fully sequenced genomes, are the second most studied group after mammalian papillomaviruses. In this study, we describe the first oral avian papillomavirus, detected in the tongue of a dead Yorkshire canary (Serinus canaria) and in oral swabs of the same bird and other two live canaries from an aviary in Madrid, Spain. Its genome is 8,071 bp and presents the canonical papillomavirus architecture with six early (E6, E7, E1, E9, E2, E4) and two late open reading frames (L1 and L2) and a long control region between L1 and E6. This new avian papillomavirus L1 gene shares a 64% pairwise identity with FcPV1 L1, so it has been classified as a new species (ScPV1) within the Ethapapillomavirus genus. Although the canary died after showing breathing problems, there is no evidence that the papillomavirus caused those symptoms so it could be part of the oral microbiota of the birds. Hence, future investigations are needed to evaluate the clinical relevance of the virus. 相似文献
2.
AIM:To observe changes of serum asymmetry dimethylarginine (ADMA) and endothelin-1 (ET-1) levels,which reflect blood vessel endothelial function,after therapy of enhanced external counterpulsation(EECP) in patients who had taken percutaneous transluminal coronary angioplasty and stent.METHODS:Fifty one coronary heart disease patients (all of them had taken percutaneous tranluminal coronary angioplasty and stent) were distributed into two groups by matching them with ratio of 1∶2,17 patients in EECP group and 34 patients in control group.Both of two groups were given conventional medicine,in addition,EECP group was undertaken three courses of treatment of EECP.ADMA was detected by HPLC-fluorescence method,and ET-1 was detected by radio-immunity method.RESULTS:In EECP group ,compared with prior treatment,ADMA and ET-1 levels was obviously reduced (P<0.05).In control group,compared with prior treatment,ADMA had no significant difference (P>0.05) and ET-1 was higher (P<0.01).Compared between two groups,extent of decrease in ADMA and ET-1 levels in EECP group were more obvious than control group (P<0.01).Improvement of angina and decrease of frequency of angina was more obvious in EECP group than control group.Besides,decrease of ADMA level was positive correlation with them (r=0.85,0.70,respectively P<0.01).CONCLUSION:EECP reduces serum ADMA and ET-1 levels by increasing shear stress to vessel endothelium in coronary heart disease patients who had taken percutaneous tranluminal coronary angioplasty.It hints that EECP can improve endothelial function and provides experimental evidence for the combined treatment of coronary heart disease. 相似文献
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Raphaël Trouvé Thomas Drapela Thomas Frank Franz Hadacek Johann G. Zaller 《Biology and Fertility of Soils》2014,50(1):13-23
Invasion of non-native species is among the top threats for the biodiversity and functioning of native and agricultural ecosystems worldwide. We investigated whether the herbivory of the slug Arion vulgaris (formerly Arion lusitanicus; Gastropoda), that is listed among the 100 worst alien species in Europe, is affected by soil organisms commonly present in terrestrial ecosystems (i.e. earthworms—Annelida: Lumbricidae and arbuscular mycorrhizal fungi—AMF, Glomerales). We hypothesized that slug herbivory would be affected by soil organisms via altered plant nutrient availability and plant quality. In a greenhouse experiment, we created a simple plant community consisting of a grass, a forb, and a legume species and inoculated these systems with either two earthworm species and/or four AMF taxa. Slugs were introduced after plants were established. Earthworms significantly reduced total slug herbivory in AMF-inoculated plant communities (P?=?0.013). Across plant species, earthworms increased leaf total N and secondary metabolites, AMF decreased leaf thickness. Mycorrhizae induced a shift in slug feeding preference from non-legumes to legumes; the grass was generally avoided by slugs. AMF effects on legume herbivory can partly be explained by the AMF-induced increase in total N and decrease in C/N ratio; earthworm effects are less clear as no worm-induced alterations of legume plant chemistry were observed. The presence of earthworms increased average AMF colonization of plant roots by 140 % (P?<?0.001). Total shoot mass was significantly increased by AMF (P?<?0.001). These data suggest that the feeding behavior of this invasive slug is altered by a belowground control of plant chemical quality and community structure. 相似文献
8.
M. Sajjad Mirza Samina Mehnaz Philippe Normand Claire Prigent-Combaret Yvan Moënne-Loccoz René Bally Kauser A. Malik 《Biology and Fertility of Soils》2006,43(2):163-170
Nitrogen-fixing plant growth-promoting rhizobacteria (PGPR) from the genus Pseudomonas have received little attention so far. In the present study, a nitrogen-fixing phytohormone-producing bacterial isolate from kallar grass (strain K1) was identified as Pseudomonas sp. by rrs (16S ribosomal RNA gene) sequence analysis. rrs identity level was high with an uncharacterized marine bacterium (99%), Pseudomonas sp. PCP2 (98%), uncultured bacteria (98%), and Pseudomonas alcaligenes (97%). Partial nifH gene amplified from strain K1 showed 93% and 91% sequence similarities to those of Azotobacter chroococcum and Pseudomonas stutzeri, respectively. The effect of Pseudomonas strain K1 on rice varieties Super Basmati and Basmati 385 was compared with those of three non-Pseudomonas nitrogen-fixing PGPR (Azospirillum brasilense strain Wb3, Azospirillum lipoferum strain N4 and Zoogloea strain Ky1) used as single-strain inoculants. Pseudomonas sp. K1 was detected in the rhizosphere of inoculated plants by enrichment culture in nitrogen-free growth medium, which was followed by observation under the microscope as well as by PCR using a rrs-specific primer. For both rice varieties, an increase in shoot biomass and/or grain yield over that of noninoculated control plants was recorded in each inoculated treatment. The effect of Pseudomonas strain K1 on grain yield was comparable to those of A. brasilense Wb3 and Zoogloea sp. Ky1 for both rice varieties. These results show that nitrogen-fixing pseudomonads deserve attention as potential PGPR inoculants for rice. 相似文献
9.
Mehinagic E Royer G Symoneaux R Jourjon F Prost C 《Journal of agricultural and food chemistry》2006,54(7):2678-2687
The aroma and texture of three different apple cultivars, harvested at three maturity stages, were analyzed by sensory and instrumental analysis. The emphasis was on the identification of the most potent odorant volatiles, and the challenge was to separate the few most important flavor compounds, which may be trace chemicals, from the vast number of nonodorant compounds present in apple aroma extracts. Thirty-six odorant compounds were detected, 24 of which were common to all extracts. A significant correlation coefficient was found between the aroma intensity scores and overall quantity of the odorant volatiles, which shows that the development of sensory aroma is similar to that of odorant volatiles. This study also showed that the parameters measured by penetrometry and compression were highly correlated with sensory textural attributes. The determination of the optimal maturity stage for different apple cultivars by the usual parameters, such as color, diameter, total soluble solids, and titrable acidity, may not be sufficient to determine the optimal sensory quality for consumers. Moreover, the sensory quality of fruits changes during maturation in a different way from one cultivar to another, and this should be taken into account. 相似文献
10.
台湾桤木采穗圃建立及扦插繁殖技术研究 总被引:1,自引:0,他引:1
经过2a多对台湾桤木采穗圃的建立和管理及扦插试验研究,结果表明:(1)0.5a生优树建立的采穗圃第2a的株采穗量达71条;(2)400mg·L^-1GGR6号生根粉水溶液浸泡的插穗生根率最高,达96.5%,清水处理的穗条效果最差,生根率为67.6%;(3)一年中插穗在6月、9月扦插效果最好,成活率分别可达96.67%、97.35%;(4)插穗摘除1/3叶片扦插效果最好,生根率迭96.3%;(5)母树上部穗条扦插效果最佳,成活率可达97%;(6)台湾桤木插穗以皮部生根为主,属于皮部和愈伤组织混合生根型,夏季扦插60d后成活穗条皮部生根的占83.33%。 相似文献