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排序方式: 共有478条查询结果,搜索用时 171 毫秒
111.
Raghvendra Pratap Singh Ram Nageena Singh Manish K Srivastava Alok Kumar Srivastava Sudheer Kumar Ramesh Chandra Dubey Arun Kumar Sharma 《Bioinformation》2012,8(21):1042-1046
Methylobacteria are ubiquitous in the biosphere which are capable of growing on C1 compounds such as formate, formaldehyde,
methanol and methylamine as well as on a wide range of multi-carbon growth substrates such as C2, C3 and C4 compounds due to
the methylotrophic enzymes methanol dehydrogenase (MDH). MDH is performing these functions with the help of a key protein
mxaF. Unfortunately, detailed structural analysis and homology modeling of mxaF is remains undefined. Hence, the objective of
this research is the characterization and three dimensional modeling of mxaF protein from three different methylotrophs by using
I-TASSER server. The predicted model were further optimize and validate by Profile 3D, Errat, Verifiy3-D and PROCHECK server.
Predicted and best evaluated models have been successfully deposited to PMDB database with PMDB ID PM0077505, PM0077506
and PM0077507. Active site identification revealed 11, 13 and 14 putative functional site residues in respected models. It may play a
major role during protein-protein, and protein-cofactor interactions. This study can provide us an ab-initio and detail information to
understand the structure, mechanism of action and regulation of mxaF protein. 相似文献
112.
Rakesh Sanabam Bharat Gopalrao Somkuwar Gourshyam Thingnam Sila Moirangthem Pratap Jyoti Handique Sunitibala Huidrom 《Bioinformation》2012,8(17):838-840
The rich wealth of Citrus genetic resources makes India to enjoy a remarkable position in the “Citrus belt of the world”. We have
developed CIBMAN, a unique database on Citrus biodiversity of Manipur which comprises 33 accessions collected through
extensive survey for more than three years. CIBMAN provides integrated access to Citrus species through sophisticated web interface
which has following capabilities a) morphological details, b) socio-economic details, c) taxonomic details and d) geographical
distribution. Morphological variability among Citrus accessions is due to variance in their genome which contributes to diverse
agronomical traits and diverse bioactive compounds of high value. This diverse gene pool can be potential source for genetic
improvement of existing cultivars and rootstocks. Systematic collection, characterization and conservation of the underutilized or
lesser exploited varieties is required for incorporating in breeding program and conserve the germplasm from ever going on
genetic erosion. This database will be useful for scientific validations and updating of traditional wisdom in bioprospecting aspects
especially industrialization of Citrus found in the state. Further, the features will be suited for detailed investigation on potential
medicinal and edible Citrus that make CIBMAN a powerful tool for sustainable management.
Availability
http://ibsd.gov.in/cibman 相似文献113.
Effect of particulate pollution on rate of transpiration in Shorea robusta at Lalpahari forest 总被引:1,自引:0,他引:1
The effect of stone dust deposition on the rate of transpiration in Shorea robusta was studied in three principal seasons in a polluted forest in comparison to an almost non-polluted forest. The extent of particulate pollution was determined by measuring suspended particulate matter in the air and dust fall on leaf surface. Macroscopic and microscopic leaf injury symptoms were studied. Scanning electron microscopic examination of leaf surfaces revealed a number of foliar anomalies. Qualitative determination of rate of transpiration in field condition was done by ‘cobalt chloride method’. It was found that transpiration was diminished as a result of foliar dust deposition which not only caused blockage of stomatal aperture but also physical damage to the leaf surface. Thus, particulate air pollution can be considered as one of the external factors regulating the rate of transpiration in plants. 相似文献
114.
In vitro propagation of rose--a review 总被引:1,自引:0,他引:1
In vitro propagation of rose has played a very important role in rapid multiplication of cultivars with desirable traits and production of healthy and disease-free plants. During the last several years, different approaches have been made for in vitro propagation of rose. Micropropagation using apical buds or nodal segments and understanding the specific requirements at different stages has been comprehensively covered in literature. New challenges for refinements of protocols for high rate of shoot multiplication and development of cost effective methods has gained importance in the recent past. Importance of liquid static culture for shoot proliferation and root induction for rose is also discussed in the present review. Further, the development of protocol for in vitro plant regeneration which is considered as most important step for successful implementation of various biotechnological techniques used for plant improvement programmes has been adequately addressed in literature. In rose, there are several reports which indicate rapid regeneration and multiplication through organogenesis or somatic embryogenesis. On the whole, the present review gives a consolidated account of in vitro propagation in rose. 相似文献
115.
Both H(2)O(2) and NO can act as apoptogens, triggering apoptosis in many cells. They are also well known inhibitors of caspases, essential enzymes in apoptosis. The differences between these two agents as apoptosis inducers and how caspases mediate apoptosis with these inhibitory agents is still unclear. Consistent with the previous reports, these two agents induced apoptosis accompanied by caspase activation with limitation of all apoptotic events for NO. It was found that NO-modified caspase-3 showed a slower recovery of its activity in the presence of the reducing agents compared to that of H(2)O(2) modification. This is one possible cause of the limited apoptosis in the case of NO. 相似文献
116.
Verena Ilona Carrara Julien Zwang Elizabeth A. Ashley Ric N. Price Kasia Stepniewska Marion Barends Alan Brockman Tim Anderson Rose McGready Lucy Phaiphun Stephane Proux Michele van Vugt Robert Hutagalung Khin Maung Lwin Aung Pyae Phyo Piyanuch Preechapornkul Mallika Imwong Sasithon Pukrittayakamee Pratap Singhasivanon Nicholas J. White Fran?ois Nosten 《PloS one》2009,4(2)
Background
Artemisinin combination treatments (ACT) are recommended as first line treatment for falciparum malaria throughout the malaria affected world. We reviewed the efficacy of a 3-day regimen of mefloquine and artesunate regimen (MAS3), over a 13 year period of continuous deployment as first-line treatment in camps for displaced persons and in clinics for migrant population along the Thai-Myanmar border.Methods and Findings
3,264 patients were enrolled in prospective treatment trials between 1995 and 2007 and treated with MAS3. The proportion of patients with parasitaemia persisting on day-2 increased significantly from 4.5% before 2001 to 21.9% since 2002 (p<0.001). Delayed parasite clearance was associated with increased risk of developing gametocytaemia (AOR = 2.29; 95% CI, 2.00–2.69, p = 0.002). Gametocytaemia on admission and carriage also increased over the years (p = 0.001, test for trend, for both). MAS3 efficacy has declined slightly but significantly (Hazards ratio 1.13; 95% CI, 1.07–1.19, p<0.001), although efficacy in 2007 remained well within acceptable limits: 96.5% (95% CI, 91.0–98.7). The in vitro susceptibility of P. falciparum to artesunate increased significantly until 2002, but thereafter declined to levels close to those of 13 years ago (geometric mean in 2007: 4.2 nM/l; 95% CI, 3.2–5.5). The proportion of infections caused by parasites with increased pfmdr1 copy number rose from 30% (12/40) in 1996 to 53% (24/45) in 2006 (p = 0.012, test for trend).Conclusion
Artesunate-mefloquine remains a highly efficacious antimalarial treatment in this area despite 13 years of widespread intense deployment, but there is evidence of a modest increase in resistance. Of particular concern is the slowing of parasitological response to artesunate and the associated increase in gametocyte carriage. 相似文献117.
Sheelendra Pratap Singh Girish Kumar Jain 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2009,877(11-12):1133-1139
A simple, sensitive and rapid method for the analysis of lumefantrine in rat plasma using liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS) was developed. Detection was performed by positive ion electrospray ionization (ESI) in multiple reaction monitoring (MRM) mode. The method included a chromatographic run of 5 min using a C18 analytical column and the calibration curve was linear over the concentration range of 2–500 ng/mL with a correlation coefficient (r) of 0.996 or better. The intra- and inter-day assay precision ranged from 1.5 to 7.5% and 5.5 to 7.7%, respectively, and intra- and inter-day assay accuracy was between 91.3–109.7% and 97.0–104.7%, respectively. The method was successfully applied for the pharmacokinetic study in rats. 相似文献
118.
Rajeev Pratap Singh Amit K. Gupta M. Hakimi Ibrahim Atul Kumar Mittal 《Reviews in Environmental Science and Biotechnology》2010,9(4):345-358
Over the past few decades there has been avid interest in developing the strategies for the utilization of Fly ash (FA). Major
foci have been on its agricultural application. It is often economical to use FA as a soil amendment. The potential of FA
as a resource material in agriculture is due to its specific physical properties like’s texture, water holding capacity, bulk
density, pH etc., and contains almost all the essential plant nutrients. It can be used as in soil that cannot substitute
the chemical fertilizers or organic manure it can be used in combination with these to get additional benefits in terms of
improvement in soil physical characteristics, increased yields etc. The amount and method of FA application in soil would
vary with the type of soil, the crop, grown, the prevailing agro climatic condition and also with the FA characteristics.
Although, as an input material FA has many benefits for agriculture applications like, improvement of nutrient deficiency,
effectively control various pests infesting etc., in contrast FA also contains number of toxic heavy metals and also have
natural radioactivity materials in it. Therefore, proper attention should be given on some important areas related to FA utilization
such as long term studies of impact of FA on soil health, heavy metal uptake, plant physiology and growth, crop quality, and
continuous monitoring on the soil characteristics. While using FA in agriculture problem of heavy metal toxicity and leaching
due to excess dose should also be kept in mind. 相似文献
119.
Fernandez-Recio J Walas F Federici L Venkatesh Pratap J Bavro VN Miguel RN Mizuguchi K Luisi B 《FEBS letters》2004,578(1-2):5-9
In Gram-negative bacteria, drug resistance is due in part to the activity of transmembrane efflux-pumps, which are composed of three types of proteins. A representative pump from Escherichia coli is an assembly of the trimeric outer-membrane protein TolC, which is an allosteric channel, the trimeric inner-membrane proton-antiporter AcrB, and the periplasmic protein, AcrA. The pump displaces drugs vectorially from the bacterium using proton electrochemical force. Crystal structures are available for TolC and AcrB from E. coli, and for the AcrA homologue MexA from Pseudomonas aeruginosa. Based on homology modelling and molecular docking, we show how AcrA, AcrB and TolC might assemble to form a tripartite pump, and how allostery may occur during transport. 相似文献
120.