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排序方式: 共有490条查询结果,搜索用时 15 毫秒
71.
Reddy MV Billa VK Pallela VR Mallireddigari MR Boominathan R Gabriel JL Reddy EP 《Bioorganic & medicinal chemistry》2008,16(7):3907-3916
A series of 20 novel 1-(4-sulfamylphenyl)-3-trifluoromethyl-5-indolyl pyrazolines were designed, synthesized, and screened in vitro for anti-inflammatory activity. These compounds were designed for evaluation as dual inhibitors of cyclooxygenases (COX-1 and COX-2) and lipoxygenases (LOX-5, LOX-12, and LOX-15) that are responsible for inflammation and pain. All pyrazoline molecules prepared are optically active and compounds that are more potent in COX-2 inhibitory activity (5a and 5f) were resolved by chiral column and each enantiomer was tested for cyclooxygenase inhibitory activity. Molecular modeling and comparison of molecular models of 5a enantiomers with that of celecoxib model shows that 5a (enantiomer-1) and 5a (enantiomer-2) have more hydrogen bonding interactions in the catalytic domain of COX-2 enzyme than celecoxib. Compounds 5a, 5e, and 5f showed moderate to good LOX-5 and LOX-15 inhibitory activity and this is comparable to that of celecoxib and more potent than rofecoxib. 相似文献
72.
73.
Venkata Ramana Doddi 《Carbohydrate research》2009,344(5):606-8464
Synthesis of polyhydroxylated oxabicyclo[4,4,0]decanes, which constitute a new family of annulated carbasugars, has been accomplished in a stereoselective manner by employing readily available 1,2-anhydro-3,4,6-tri-O-benzyl-α-d-glycopyranoses. 相似文献
74.
M. V. Ramana Rao K. S. Behera N. Baisakh S. K. Datta G. J. N. Rao 《Plant Cell, Tissue and Organ Culture》2009,99(3):277-285
Transgenic rice was developed from ‘Swarna’, the most popular indica rice cultivar (Oryza sativa L.) in South East Asia, with a potato chymotrypsin inhibitor gene (pin2) through Agrobacterium-mediated transformation. Four out of nine primary transgenic plants had a single-copy T-DNA insertion while other five plants
had two copies. Mendelian pattern of inheritance of the transgene (pin2) was observed in the T1 generation progeny plants. Whole plant bioassays conducted at both vegetative and reproductive stages and cut stem assays
showed enhanced levels of resistance of transgenic rice against yellow stem borer. The transgenic rice lines with plant derived
proteinase inhibitor genes would develop into resistant cultivars to fit into resistance breeding strategies as an important
component of integrated pest management in rice. 相似文献
75.
Many natural and biological systems including collagen and DNA polymers are formed by a process of molecular self-assembly. In this paper, we developed two novel structural models and built heterogeneous DNA/collagen complexes through a preferable arrangement of multiple hydrogen bonds (H-bonds) between DNA and collagen molecules. The simulation results based on three sets of criteria indicate that one of the models with five collagen molecules, which are positioned around each strand of DNA molecules emerged to form a suitable polymer complex with the maximum number of H-bonds. Our predictions quantitatively validated and agreed with the molecular structure reported by Mrevlishvili and Svintradze [2005. Int. J. Biol. Macromol. 36, 324-326]. 相似文献
76.
K. Samuel D. Debashish B. Madhumita G. Padmaja Siva Ram Prasad V. Bhaskara Ramana Murthy P. S. Rao 《In vitro cellular & developmental biology. Plant》2009,45(4):466-473
The propagation of Givotia rottleriformis Griff. is difficult as a result of long seed dormancy associated with poor seed germination. The present study was undertaken
to develop a protocol to overcome seed dormancy by culture of zygotic embryo axes and then develop an efficient method for
micropropagation of Givotia. Best germination frequency (78.3%) was achieved from mature zygotic embryo axes isolated from acid-scarified fresh seeds
when cultured on Murashige and Skoog (MS) medium (half-strength major salts) with 28.9 μM gibberellic acid (GA3). Efficient plant conversion was achieved by transfer of 10-d-old germinated embryos to MS medium (half-strength major salts)
supplemented with 1.2 μM kinetin (KN) and 0.5 μM indole-3-butyric acid (IBA). However, acid scarification of 1-yr-old seeds
decreased the germination frequency of zygotic embryo axes in comparison to those obtained from non-acid-scarified seeds which
germinated (96.2%) and converted into plants (80.3%) on MS basal (half-strength major salts) medium. Multiple shoot bud induction
was achieved by culture of shoot tips derived from in vitro germinated seedlings on MS medium with 0.5 μM thidiazuron for 4 wk, and the shoots elongated after transfer to a secondary
medium with 1.2 μM KN. A maximum number of 7.8 shoots per explant with an average shoot length of 3.2 cm was achieved after
two subcultures on this medium. The in vitro regenerated shoots rooted (41.5%) on half-strength MS medium with 0.5 μM IBA. The in vitro generated seedlings and micropropagated plants were established in soil with a survival frequency of 70% and 60%, respectively. 相似文献
77.
78.
Dongying Wu Jason Raymond Martin Wu Sourav Chatterji Qinghu Ren Joel E. Graham Donald A. Bryant Frank Robb Albert Colman Luke J. Tallon Jonathan H. Badger Ramana Madupu Naomi L. Ward Jonathan A. Eisen 《PloS one》2009,4(1)
In order to enrich the phylogenetic diversity represented in the available sequenced bacterial genomes and as part of an “Assembling the Tree of Life” project, we determined the genome sequence of Thermomicrobium roseum DSM 5159. T. roseum DSM 5159 is a red-pigmented, rod-shaped, Gram-negative extreme thermophile isolated from a hot spring that possesses both an atypical cell wall composition and an unusual cell membrane that is composed entirely of long-chain 1,2-diols. Its genome is composed of two circular DNA elements, one of 2,006,217 bp (referred to as the chromosome) and one of 919,596 bp (referred to as the megaplasmid). Strikingly, though few standard housekeeping genes are found on the megaplasmid, it does encode a complete system for chemotaxis including both chemosensory components and an entire flagellar apparatus. This is the first known example of a complete flagellar system being encoded on a plasmid and suggests a straightforward means for lateral transfer of flagellum-based motility. Phylogenomic analyses support the recent rRNA-based analyses that led to T. roseum being removed from the phylum Thermomicrobia and assigned to the phylum Chloroflexi. Because T. roseum is a deep-branching member of this phylum, analysis of its genome provides insights into the evolution of the Chloroflexi. In addition, even though this species is not photosynthetic, analysis of the genome provides some insight into the origins of photosynthesis in the Chloroflexi. Metabolic pathway reconstructions and experimental studies revealed new aspects of the biology of this species. For example, we present evidence that T. roseum oxidizes CO aerobically, making it the first thermophile known to do so. In addition, we propose that glycosylation of its carotenoids plays a crucial role in the adaptation of the cell membrane to this bacterium''s thermophilic lifestyle. Analyses of published metagenomic sequences from two hot springs similar to the one from which this strain was isolated, show that close relatives of T. roseum DSM 5159 are present but have some key differences from the strain sequenced. 相似文献
79.
P. Ramu S. P. Deshpande S. Senthilvel B. Jayashree C. Billot M. Deu L. Ananda Reddy C. T. Hash 《Molecular breeding : new strategies in plant improvement》2010,26(3):409-418
Crop genome sequencing projects generate massive amounts of genomic sequence information, and the utilization of this information
in applied crop improvement programs has been augmented by the availability of sophisticated bioinformatics tools. Here, we
present the possible direct utilization of sequence data from a sorghum genome sequencing project in applied crop breeding
programs. Based on sequence homology, we aligned all publicly available simple sequence repeat markers on a sequence-based
physical map for sorghum. Linking this physical map with already existing linkage map(s) provides better options for applied
molecular breeding programs. When a new set of markers is made available, the new markers can be first aligned on a sequence-based
physical map, and those located near the quantitative trait locus (QTL) can be identified from this map, thereby reducing
the number of markers to be tested in order to identify polymorphic flanking markers for the QTL for any given donor × recurrent
parent combination. Polymorphic markers that are expected (on the basis of their position on the sequence-based physical map)
to be closely linked to the target can be used for foreground selection in marker-assisted breeding. This map facilitates
the identification of a set of markers representing the entire genome, which would provide better resolution in diversity
analyses and further linkage disequilibrium mapping. Filling the gaps in existing linkage maps and fine mapping can be achieved
more efficiently by targeting the specific genomic regions of interest. It also opens up new exciting opportunities for comparative
mapping and for the development of new genomic resources in related crops, both of which are lagging behind in the current
genomic revolution. This paper also presents a number of examples of potential applications of sequence-based physical map
for sorghum. 相似文献
80.
Venkata Ramana Naidu Rucha S. Deshpande Moinuddin R. Syed Piyush Deoghare Dharamvir Singh Pravin S. Wakte 《AAPS PharmSciTech》2017,18(6):2045-2054
Current endeavor was aimed towards monitoring percent weight build-up during functional coating process on drug-layered pellets. Near-infrared (NIR) spectroscopy is an emerging process analytical technology (PAT) tool which was employed here within quality by design (QbD) framework. Samples were withdrawn after spraying every 15-Kg cellulosic coating material during Wurster coating process of drug-loaded pellets. NIR spectra of these samples were acquired using cup spinner assembly of Thermoscientific Antaris II, followed by multivariate analysis using partial least squares (PLS) calibration model. PLS model was built by selecting various absorption regions of NIR spectra for Ethyl cellulose, drug and correlating the absorption values with actual percent weight build up determined by HPLC. The spectral regions of 8971.04 to 8250.77 cm?1, 7515.24 to 7108.33 cm?1, and 5257.00 to 5098.87 cm?1 were found to be specific to cellulose, where as the spectral region of 6004.45 to 5844.14 cm?1was found to be specific to drug. The final model gave superb correlation co-efficient value of 0.9994 for calibration and 0.9984 for validation with low root mean square of error (RMSE) values of 0.147 for calibration and 0.371 for validation using 6 factors. The developed correlation between the NIR spectra and cellulose content is useful in precise at-line prediction of functional coat value and can be used for monitoring the Wurster coating process. 相似文献