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排序方式: 共有218条查询结果,搜索用时 15 毫秒
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Evaluation of maize microsatellite markers for genetic diversity analysis and fingerprinting in sugarcane. 总被引:4,自引:0,他引:4
The use of maize microsatellite markers as a potential cost-effective method for molecular analysis of sugarcane was evaluated. Of the 34 primer pairs obtained from maize genomic libraries, 14 showed repeatable amplifications in Saccharum species clones, commercial hybrids, and the related genera Erianthus, accounting for 41.17% cross transferability. Complex banding patterns were encountered in sugarcane with the number of amplified fragments ranging from 7 to 14 with an average of 10 per primer, indicating the high polyploidy and heterozygosity existing in sugarcane. Phenetic analysis of the SSR polymorphisms produced by nine primers could clearly differentiate the different species of Saccharum and Erianthus and revealed the relationships that existed between them. Genetic similarity co-efficient indicated low diversity existing among the S. officinarum clones (82%) and a relatively higher level of diversity in the S. spontaneum clones (69.7%). Higher level of divergence of Erianthus from Saccharum was also clearly estabilished. Five primers produced genus- and species-specific fragments for Erianthus, S. spontaneum, S. officinarum, and S. barberi. The polymorphic primers, when tested on a panel of 30 commercial sugarcane cultivars, revealed a broad range (32.4-83.3%) of pair-wise similarity values, indicating their ability to detect high levels of polymorphism. A combination of two primers could differentiate all the varieties, further emphasizing their potential in fingerprinting and varietal identification. 相似文献
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Deepa Selvi Rani Perundurai S. Dhandapany Pratibha Nallari Calambur Narasimhan Kumarasamy Thangaraj 《PloS one》2014,9(7)
Cardiomyopathy is a major cause of heart failure and sudden cardiac death; several mutations in sarcomeric protein genes have been associated with this disease. Our aim in the present study is to investigate the genetic variations in Troponin T (cTnT) gene and its association with dilated cardiomyopathy (DCM) in south-Indian patients. Analyses of all the exons and exon-intron boundaries of cTnT in 147 DCM and in 207 healthy controls had revealed a total of 15 SNPs and a 5 bp INDEL; of which, polymorphic SNPs were compared with the HapMap population data. Interestingly, a novel R144W mutation, that substitutes polar-neutral tryptophan for a highly conserved basic arginine in cTnT, altering the charge drastically, was identified in a DCM, with a family history of sudden-cardiac death (SCD). This mutation was found within the tropomyosin (TPM1) binding domain, and was evolutionarily conserved across species, therefore it is expected to have a significant impact on the structure and function of the protein. Family studies had revealed that the R144W is co-segregating with disease in the family as an autosomal dominant trait, but it was completely absent in 207 healthy controls and in 162 previously studied HCM patients. Further screening of the proband and three of his family members (positive for R144W mutant) with eight other genes β-MYH7, MYBPC3, TPM1, TNNI3, TTN, ACTC, MYL2 and MYL3, did not reveal any disease causing mutation, proposing the absence of compound heterozygosity. Therefore, we strongly suggest that the novel R144W unique/private mutant identified in this study is associated with FDCM. This is furthermore signifying the unique genetic architecture of Indian population. 相似文献
45.
Pretreatment of coconut mill effluent using celite‐immobilized hydrolytic enzyme preparation from Staphylococcus pasteuri and its impact on anaerobic digestion 下载免费PDF全文
Palanisamy Kanmani Kuppamuthu Kumaresan Jeyaseelan Aravind 《Biotechnology progress》2015,31(5):1249-1258
Biological treatment of oil and grease (O&G)‐containing industrial effluents has long been a challenging issue. Practically feasible avenues to bring down their O&G load and enhance treatability are desired. In one such endeavour, the partially purified lipase from Staphylococcus pasteuri COM‐4A was immobilized on celite carrier and applied for the enzymatic hydrolysis of unsterilized coconut oil mill effluent. In batch hydrolysis experiments, optimum conditions of 1% (w/v) immobilized lipase beads, one in four effluent dilution, and a contact time of 30 h resulted in 46% and 24% increase in volatile fatty acids and long‐chain fatty acids and a concomitant 52% and 32% decrease in O&G and chemical oxygen demand (COD) levels, respectively. Batch anaerobic biodegradation trials with this prehydrolyzed effluent showed 89%, 91%, and 90% decrease in COD, proteins, and reducing sugars, respectively. These results were validated in a hybrid stirred tank—upflow anaerobic sludge blanket reactor. Average COD and O&G reductions effected by the hybrid reactor were found to be 89% and 88%, whereas that by the control reactor without enzymatic hydrolysis were only 60% and 47%, respectively. A maximum of 0.86 L methane gas was generated by the hybrid reactor per gram of VS added. Hence, this celite‐immobilized crude lipase, sourced from a native laboratory isolate, seems to be a workable alternative to commercial enzyme preparations for the management of lipid‐rich industrial effluents. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1249–1258, 2015 相似文献
46.
A new species of Anchusa, A. samothracica. is described from the island of Samothraki, in the north-eastern Aegean sea. The species belongs to subg. Anchusa but shows a phenotypic differentiation from the Mediterranean and Anatolian congeneric taxa for a particular combination of vegetative and floral characters. Ecological traits are also peculiar, the species being restricted to the unique sandy beach of the island. SEM analyses provide additional information on the micromorphology of the indumentum, pollen grains, shape and receptive surface of the stigma, and mericarp coat surface. Some aspects concerning the systematic relationships and possible origin of the species are discussed. Due to its ecological specialization and localization in a site subjected to heavy goat grazing and touristic impact, A. samothracica is in need of total protection in its natural habitat and should be added to the Red Lists of plants of the European Community. A lectotype for Anchusa sartorii Gusul., a Greek endemic, is also designated. 相似文献
47.
Narayanasamy Angayarkanni Radhakrishnan Selvi Rishi Pukhraj Jyotirmoy Biswas Shah J. Bhavesh Joyce Tombran-Tink 《Journal of ocular biology, diseases, and informatics》2009,2(1):20-28
Eales disease (ED) is an idiopathic inflammatory venous occlusion of the peripheral retina. As neovascularization is prominent in ED, this study attempts to look at the ratio of VEGF, the angiogenic factor, and PEDF, an anti-angiogenic factor in the vitreous of ED patients in comparison with the macular hole (MH) and Proliferative Diabetic Retinopathy (PDR). Vitreous levels of VEGF and PEDF were determined in the undiluted vitreous specimen obtained from 26 ED cases, 17 PDR, and seven patients with MH. The vitreous levels of VEGF and PEDF were estimated by ELISA. The immunohistochemistry (IHC) for VEGF and PEDF were done in the epiretinal membrane of ED and PDR case. The VEGF/PEDF ratio was found to be significantly increased in ED (p = 0.014) and PDR (p = 0.000) compared to MH. However the ratio was 3.5-fold higher in PDR than ED (p = 0.009). The IHC data on the ERM specimen from ED showed the presence of VEGF and PEDF similar to PDR. The high angiogenic potential seen as the ratio of VEGF/PEDF correlates with the peak clinical onset of the disease in the age group 21–30 years and the diseases usually self-resolves above the age of 40, which is reflected by the low ratio of VEGF/PEDF. The study shows that the VEGF/PEDF ratio is significantly increased in ED though the angiogenic potential is higher in PDR than in ED. Clinically Eales Disease is known as a self-limiting disease, while PDR is a progressive disease. 相似文献
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Pieter Sanczuk Sanne Govaert Camille Meeussen Karen De Pauw Thomas Vanneste Leen Depauw Xoaquín Moreira Jonas Schoelynck Marthe De Boevre Sarah De Saeger Kurt Bollmann Jrg Brunet Sara A. O. Cousins Jan Plue Martin Diekmann Bente J. Graae Per‐Ola Hedwall Giovanni Iacopetti Jonathan Lenoir Anna Orczewska Quentin Ponette Federico Selvi Fabien Spicher Pieter Vermeir Kim Calders Hans Verbeeck Kris Verheyen Pieter Vangansbeke Pieter De Frenne 《Global Ecology and Biogeography》2021,30(1):205-219
50.
Pedarzani P D'hoedt D Doorty KB Wadsworth JD Joseph JS Jeyaseelan K Kini RM Gadre SV Sapatnekar SM Stocker M Strong PN 《The Journal of biological chemistry》2002,277(48):46101-46109
The biophysical properties of small conductance Ca(2+)-activated K(+) (SK) channels are well suited to underlie afterhyperpolarizations (AHPs) shaping the firing patterns of a conspicuous number of central and peripheral neurons. We have identified a new scorpion toxin (tamapin) that binds to SK channels with high affinity and inhibits SK channel-mediated currents in pyramidal neurons of the hippocampus as well as in cell lines expressing distinct SK channel subunits. This toxin distinguished between the SK channels underlying the apamin-sensitive I(AHP) and the Ca(2+)-activated K(+) channels mediating the slow I(AHP) (sI(AHP)) in hippocampal neurons. Compared with related scorpion toxins, tamapin displayed a unique, remarkable selectivity for SK2 versus SK1 ( approximately 1750-fold) and SK3 ( approximately 70-fold) channels and is the most potent SK2 channel blocker characterized so far (IC(50) for SK2 channels = 24 pm). Tamapin will facilitate the characterization of the subunit composition of native SK channels and help determine their involvement in electrical and biochemical signaling. 相似文献