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61.
Robert NG Miller David J Bertioli Franc C Baurens Candice MR Santos Paulo C Alves Natalia F Martins Roberto C Togawa Manoel T Souza Júnior Georgios J Pappas Júnior 《BMC plant biology》2008,8(1):15
Background
Many commercial banana varieties lack sources of resistance to pests and diseases, as a consequence of sterility and narrow genetic background. Fertile wild relatives, by contrast, possess greater variability and represent potential sources of disease resistance genes (R-genes). The largest known family of plant R-genes encode proteins with nucleotide-binding site (NBS) and C-terminal leucine-rich repeat (LRR) domains. Conserved motifs in such genes in diverse plant species offer a means for isolation of candidate genes in banana which may be involved in plant defence. 相似文献62.
63.
Rodrigo M Mota João S Luiz Moreira Marcelo R Souza M Fátima Horta Santuza MR Teixeira Elisabeth Neumann Jacques R Nicoli Álvaro C Nunes 《BMC biotechnology》2006,6(1):2-11
Background
The use of lactic acid bacteria as vehicles to delivery antigens to immunize animals is a promising issue. When genetically modified, these bacteria can induce a specific local and systemic immune response against selected pathogens. Gastric acid and bile salts tolerance, production of antagonistic substances against pathogenic microorganisms, and adhesive ability to gut epithelium are other important characteristics that make these bacteria useful for oral immunization. 相似文献64.
We studied seasonal variation of ectoparasite load (number of parasites per individual bat) in free-ranging populations of the lesser mouse-eared bat Myotis blythii in western Iran. Data for 1 species each of batfly (Nycteribidae), tick (Ixodidae), and mite (Spinturnicidae) are reported for a 1 yr period. Patterns of parasite load during this time differed considerably among species. However, the parasite load increased markedly in pregnant females in spring and early summer. During the same time frame, parasite load decreased in solitary males when they roosted apart from maternity clusters. However, in late summer, when bats began swarming, males showed a significant (P < 0.05) increase in parasite load. Using the ratio of body mass to length of forearm as an index of body condition, no significant correlation was found. 相似文献
65.
66.
Ali akbar Mozafari Faride Havas Nasser Ghaderi 《Plant Cell, Tissue and Organ Culture》2018,132(3):511-523
The effects of iron nanoparticles and salicylic acid (SA) on strawberry (Fragaria?×?ananassa Duch.) plants in conditions of drought stress were surveyed under in vitro conditions to find the optimum combination for strawberry tissue culture. Cuttings of the Queen Elisa cultivar were surveyed in a three-way factorial experiment with three replications in 2015. The results showed that drought stress significantly affected all measured parameters of strawberry plantlets under in vitro condition in a negative way. SA compensated for the negative effects of drought stress on strawberry plantlets and improved their growth parameters under in vitro culture. Strawberry plantlets treated with iron nanoparticles were able to cope with stressful conditions better than untreated ones. This study found that iron, a micronutrient in plant growth and in vitro development, greatly influenced the plantlets’ growth parameters and other measured traits. These results indicate that the efficiency of tissue culture and in vitro culture of strawberries could be improved by increased application of iron in the form of nanoparticles. The results might also indicate that the application of iron nanoparticles along with SA can be a useful method for providing higher quantity and quantity in the in vitro culture of strawberries, and could be used for adapting strawberry plants to drought before transplanting them in the field. 相似文献
67.
BD Pascal MJ Chalmers SA Busby CC Mader MR Southern NF Tsinoremas PR Griffin 《BMC bioinformatics》2007,8(1):156
Background
The combination of mass spectrometry and solution phase amide hydrogen/deuterium exchange (H/D exchange) experiments is an effective method for characterizing protein dynamics, and protein-protein or protein-ligand interactions. Despite methodological advancements and improvements in instrumentation and automation, data analysis and display remains a tedious process. The factors that contribute to this bottleneck are the large number of data points produced in a typical experiment, each requiring manual curation and validation, and then calculation of the level of backbone amide exchange. Tools have become available that address some of these issues, but lack sufficient integration, functionality, and accessibility required to address the needs of the H/D exchange community. To date there is no software for the analysis of H/D exchange data that comprehensively addresses these issues. 相似文献68.
Zhike Liang Qingling Zhang Catherine MR Thomas Kirandeep K Chana David Gibeon Peter J Barnes Kian Fan Chung Pankaj K Bhavsar Louise E Donnelly 《Respiratory research》2014,15(1):72
Background
Bacteria are frequently cultured from sputum samples of severe asthma patients suggesting a defect in bacterial clearance from the airway. We measured the capacity of macrophages from patients with asthma to phagocytose bacteria.Methods
Phagocytosis of fluorescently-labelled polystyrene beads, Haemophilus influenzae or Staphylococcus aureus by broncholaveolar lavage alveolar macrophages (AM) and by monocyte-derived macrophages (MDM) from non-asthmatics, mild-moderate and severe asthmatic patients was assessed using fluorimetry.Results
There were no differences in phagocytosis of polystyrene beads by AMs or MDMs from any of the subject groups. There was reduced phagocytosis of Haemophilus influenzae and Staphylococcus aureus in MDMs from patients with severe asthma compared to non-severe asthma (p < 0.05 and p < 0.01, respectively) and healthy subjects (p < 0.01and p < 0.001, respectively). Phagocytosis of Haemophilus influenzae and Staphylococcus aureus by AM was also reduced in severe asthma compared to normal subjects (p < 0.05). Dexamethasone and formoterol did not suppress phagocytosis of bacteria by MDMs from any of the groups.Conclusions
Persistence of bacteria in the lower airways may result partly from a reduced phagocytic capacity of macrophages for bacteria. This may contribute to increased exacerbations, airway colonization and persistence of inflammation. 相似文献69.
DAVID J. FREY CHRISTOPH R. HAAG GREGOR KOZLOWSKI JEAN‐MARC TISON PATRIK MRÁZ 《Botanical journal of the Linnean Society. Linnean Society of London》2012,169(2):365-377
Endemic plants inhabiting coastal sand dunes show augmented extinction risks due to the dynamic nature of dunes and strong human pressure on coastal areas. To investigate the survival strategies and threats to long‐term survival of such species, we combined genetic, morphological and biogeographical approaches, using the example of Hieracium eriophorum (Asteraceae) and its putative cryptic sister species H. prostratum, which are endemic to the longest coastal sand dune in Europe. An analysis of amplified fragment length polymorphism revealed high within‐population genetic variability, and slight isolation by distance was the only indication of genetic population structure. Thus, no signs of genetic threats to survival were found. Furthermore, genetic and morphometric data provided no evidence for the existence of two species. Therefore, we propose to synonymize H. prostratum with H. eriophorum and provide a nomenclatural overview with typification. Finally, an analysis of historical distribution records showed that, during the last 100 years, the species was lost from its range margins, where its habitat became fragmented. Taken together, our results suggest that one successful survival strategy of narrow endemics may be the achievement of large local population sizes on a small geographical scale, thus avoiding the genetic problems inherent to small and fragmented populations. Dune management policies should thus take care that the current tendencies to allow more erosion will not result in too severe fragmentation of the remaining continuous stretches of dune habitat. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169 , 365–377. 相似文献
70.
Nanees F El-Malkey Amira E Alsemeh Wesam MR Ashour Nancy H Hassan Husam M Edrees 《Experimental biology and medicine (Maywood, N.J.)》2021,246(11):1307
Intestinal tissue is highly susceptible to ischemia/reperfusion injury in many hazardous health conditions. The anti-inflammatory and antioxidant glycoprotein fetuin-A showed efficacy in cerebral ischemic injury; however, its protective role against intestinal ischemia/reperfusion remains elusive. Therefore, this study investigated the protective role of fetuin-A supplementation against intestinal structural changes and dysfunction in a rat model of intestinal ischemia/reperfusion. We equally divided 72 male rats into control, sham, ischemia/reperfusion, and fetuin-A-pretreated ischemia/reperfusion (100 mg/kg/day fetuin-A intraperitoneally for three days prior to surgery and a third dose 1 h prior to the experiment) groups. After 2 h of reperfusion, the jejunum was dissected and examined for spontaneous contractility. A jejunal homogenate was used to assess inflammatory and oxidative stress enzymes. Staining of histological sections was carried out with hematoxylin, eosin and Masson’s trichrome stain for evaluation. Immunohistochemistry was performed to detect autophagy proteins beclin-1, LC3, and p62. This study found that fetuin-A significantly improved ischemia/reperfusion-induced mucosal injury by reducing the percentage of areas of collagen deposition, increasing the amplitude of spontaneous contraction, decreasing inflammation and oxidative stress, and upregulating p62 expression, which was accompanied by beclin-1 and LC3 downregulation. Our findings suggest that fetuin-A treatment can prevent ischemia/reperfusion-induced jejunal structural and functional changes by increasing antioxidant activity and regulating autophagy disturbances observed in the ischemia/reperfusion rat model. Furthermore, fetuin-A may provide a protective influence against intestinal ischemia/reperfusion complications. 相似文献