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排序方式: 共有1135条查询结果,搜索用时 15 毫秒
131.
Qayyum R Snively BM Ziv E Nalls MA Liu Y Tang W Yanek LR Lange L Evans MK Ganesh S Austin MA Lettre G Becker DM Zonderman AB Singleton AB Harris TB Mohler ER Logsdon BA Kooperberg C Folsom AR Wilson JG Becker LC Reiner AP 《PLoS genetics》2012,8(3):e1002491
Several genetic variants associated with platelet count and mean platelet volume (MPV) were recently reported in people of European ancestry. In this meta-analysis of 7 genome-wide association studies (GWAS) enrolling African Americans, our aim was to identify novel genetic variants associated with platelet count and MPV. For all cohorts, GWAS analysis was performed using additive models after adjusting for age, sex, and population stratification. For both platelet phenotypes, meta-analyses were conducted using inverse-variance weighted fixed-effect models. Platelet aggregation assays in whole blood were performed in the participants of the GeneSTAR cohort. Genetic variants in ten independent regions were associated with platelet count (N?=?16,388) with p<5×10(-8) of which 5 have not been associated with platelet count in previous GWAS. The novel genetic variants associated with platelet count were in the following regions (the most significant SNP, closest gene, and p-value): 6p22 (rs12526480, LRRC16A, p?=?9.1×10(-9)), 7q11 (rs13236689, CD36, p?=?2.8×10(-9)), 10q21 (rs7896518, JMJD1C, p?=?2.3×10(-12)), 11q13 (rs477895, BAD, p?=?4.9×10(-8)), and 20q13 (rs151361, SLMO2, p?=?9.4×10(-9)). Three of these loci (10q21, 11q13, and 20q13) were replicated in European Americans (N?=?14,909) and one (11q13) in Hispanic Americans (N?=?3,462). For MPV (N?=?4,531), genetic variants in 3 regions were significant at p<5×10(-8), two of which were also associated with platelet count. Previously reported regions that were also significant in this study were 6p21, 6q23, 7q22, 12q24, and 19p13 for platelet count and 7q22, 17q11, and 19p13 for MPV. The most significant SNP in 1 region was also associated with ADP-induced maximal platelet aggregation in whole blood (12q24). Thus through a meta-analysis of GWAS enrolling African Americans, we have identified 5 novel regions associated with platelet count of which 3 were replicated in other ethnic groups. In addition, we also found one region associated with platelet aggregation that may play a potential role in atherothrombosis. 相似文献
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Molecular mechanistic model of plant heavy metal tolerance 总被引:2,自引:0,他引:2
134.
Rahul R Nair Manivasagam B Nandhini Elango Monalisha Kavitha Murugan Thilaga Sethuraman Sangeetha Nagarajan Nayani Surya Prakash Rao Doss Ganesh 《Bioinformation》2012,8(22):1096-1104
Synonymous codon usage of 53 protein coding genes in chloroplast genome of Coffea arabica was analyzed for the first time to find
out the possible factors contributing codon bias. All preferred synonymous codons were found to use A/T ending codons as
chloroplast genomes are rich in AT. No difference in preference for preferred codons was observed in any of the two strands, viz.,
leading and lagging strands. Complex correlations between total base compositions (A, T, G, C, GC) and silent base contents (A3, T3,
G3, C3, GC3) revealed that compositional constraints played crucial role in shaping the codon usage pattern of C. arabica chloroplast
genome. ENC Vs GC3 plot grouped majority of the analyzed genes on or just below the left side of the expected GC3 curve
indicating the influence of base compositional constraints in regulating codon usage. But some of the genes lie distantly below the
continuous curve confirmed the influence of some other factors on the codon usage across those genes. Influence of compositional
constraints was further confirmed by correspondence analysis as axis 1 and 3 had significant correlations with silent base contents.
Correlation of ENC with axis 1, 4 and CAI with 1, 2 prognosticated the minor influence of selection in nature but exact separation
of highly and lowly expressed genes could not be seen. From the present study, we concluded that mutational pressure combined
with weak selection influenced the pattern of synonymous codon usage across the genes in the chloroplast genomes of C. arabica. 相似文献
135.
T Joseph VG Saipradeep GS Raghavan R Srinivasan A Rao S Kotte N Sivadasan 《Bioinformation》2012,8(12):578-580
TPX is a web-based PubMed search enhancement tool that enables faster article searching using analysis and exploration features. These features include identification of relevant biomedical concepts from search results with linkouts to source databases, concept based article categorization, concept assisted search and filtering, query refinement. A distinguishing feature here is the ability to add user-defined concept names and/or concept types for named entity recognition. The tool allows contextual exploration of knowledge sources by providing concept association maps derived from the MEDLINE repository. It also has a full-text search mode that can be configured on request to access local text repositories, incorporating entity co-occurrence search at sentence/paragraph levels. Local text files can also be analyzed on-the-fly. Availability: http://tpx.atc.tcs.com 相似文献
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Plastids are functionally and structurally diverse organelles responsible for numerous biosynthetic reactions within the plant cell. Plastids from embryos have a range of properties depending upon the plant source but compared to other plastid types are poorly understood and therefore, we term them embryoplasts. Isolating intact plastids from developing embryos is challenging due to large starch granules within the stroma and the prevalence of nonplastid, storage organelles (oil bodies and protein storage vacuoles) which compromise plastid integrity and purity, respectively. To characterize rapeseed embryoplasts it was necessary to develop an improved isolation procedure. A new method is presented for the isolation of intact plastids from developing embryos of Brassica napus seeds. Intactness and purity of embryoplast preparations was determined using phase-contrast and transmission electron microscopy, immunoblotting, and multidimensional protein identification technology (MudPIT) MS/MS. Eighty nonredundant proteins were identified by MudPIT analysis of embryoplast preparations. Approximately 53% of these proteins were components of photosystem, light harvesting, cytochrome b/f, and ATP synthase complexes, suggesting ATP and NADPH production are important functions for this plastid type. 相似文献
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Pseudomonas desmolyticum NCIM 2112 (Pd 2112) and Nocardia hydrocarbonoxydans NCIM 2386 (Nh 2386) demonstrated an ability to degrade diesel and kerosene. Triton X-100 had enhanced the diesel degradation
process by reducing the time required for the maximum utilization of total petroleum hydrocarbon. Fourier transform infrared
spectroscopy spectrum of degraded diesel indicates the presence of aliphatic and aromatic aldehydes, C=C aromatic nuclei,
and substituted benzenes. Surface tension reduction and stable emulsification was increased using consortium when compared
to individual strains. Triton X-100 showed increase in microbial attachment to hydrocarbon among the various chemical surfactants
tested. For generating a rapid assay to screen microorganisms capable of degrading kerosene, the acetaldehyde produced in
the degradation process could be used as an indicator of degradation. These results indicate diesel and kerosene degradation
ability of both of the strains. 相似文献