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排序方式: 共有6091条查询结果,搜索用时 93 毫秒
81.
Sengottuvel Senthilnathan M.E. Parasakthi Chandrasekaran M.Tech. Mariyappa Narayanan M.Sc. Rajesh Patel B.Tech. Gireesan Katholil Ph.D. Madhukar P. Janawadkar M.Sc. Radhakrishnan S. Thimmakudy Ph.D. Muralidharan R. Thoddi M.D. D.M. 《Annals of noninvasive electrocardiology》2012,17(3):186-194
Background: Extraction of the weak electrical activity of the “His Bundle” (HB) by noninvasive methods has not been very successful in the past. The study reassesses the use of signal averaged magnetocardiography (SAMCG), overcoming some of the limitations in earlier studies including in the signal averaging methodology. Methods: SAMCG on healthy subjects (14 male and 1 female) were performed using R‐peak as the fiducial point in all cases and also using QRS‐onset as the fiducial point in select cases. Results: A conspicuous feature (H) with a magnitude up to 200 femto Tesla (fT) attributed to the HB activity was observed in the PR segment at several spatial positions on the thorax, with onset at 35–50 ms before the QRS‐onset (V) in 15 out of 18 trials constituting 83% of cases studied. The QRS‐onset as the fiducial point resolved the feature better compared to the conventionally used R‐peak, especially in trials exhibiting spread in heart rate (HR). This is attributed to the fluctuations in QonRD (the time interval between QRS‐onset and R‐peak) compared to the temporal stability of the H‐V duration. Conclusions: SAMCG reveals a well‐resolved H feature. The double hump morphology of the feature extended at least up to a frequency of 150 Hz. The importance of the choice of QRS‐onset as the fiducial point is unequivocally demonstrated, illustrated by measurements on subjects exhibiting considerable heart rate variability. The latter has a general validity and should be applicable to SAECG as well. 相似文献
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Vandana Singh Rajesh Kumar Biswas Bhupendra N. Singh 《Antimicrobial agents and chemotherapy》2014,58(3):1389-1396
Conventional antimycobacterial screening involves CFU analysis, which poses a great challenge due to slow growth of mycobacteria. Recombinant strains carrying reporter genes under the influence of constitutive promoters allow rapid and wide screening of compounds but without revealing their modes of action. Reporter strains using pathway-specific promoters provide a better alternative but allow a limited screening of compounds interfering with only a particular metabolic pathway. This reduces these strains to merely a second-line screening system, as they fail to identify even the more potent compounds if they are not inhibiting the pathway of interest. In this study, we have generated a double recombinant Mycobacterium bovis BCG strain carrying firefly and Renilla luciferase genes as two reporters under the control of a constitutive and an inducible mycobacterial promoter. The presence of dual reporters allows simultaneous expression and analysis of two reporter enzymes within a single system. The expression profile of the firefly luciferase gene, rendered by a constitutive mycobacterial promoter, coincides with the decline in bacterial growth in response to a wide range of antimycobacterial drugs, while the enhanced expression of Renilla luciferase mirrors the selective induction of the reporter gene expression as a result of pathway-specific inhibition. Thus, the double recombinant strain allows the screening of both primary and rationally synthesized antimycobacterial compounds in a single assay. The inhibiting response of drugs was monitored with a dual-luciferase reporter assay which can be easily adapted in high-throughput mode. 相似文献
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Alan Pan Rajesh Kumar Paul M. Macey Gregg C. Fonarow Ronald M. Harper Mary A. Woo 《Journal of cardiac failure》2013,19(2):94-100
BackgroundHeart failure (HF) patients exhibit depression and executive function impairments that contribute to HF mortality. Using specialized magnetic resonance imaging (MRI) analysis procedures, brain changes appear in areas regulating these functions (mammillary bodies, hippocampi, and frontal cortex). However, specialized MRI procedures are not part of standard clinical assessment for HF (which is usually a visual evaluation), and it is unclear whether visual MRI examination can detect changes in these structures.Methods and ResultsUsing brain MRI, we visually examined the mammillary bodies and frontal cortex for global and hippocampi for global and regional tissue changes in 17 HF and 50 control subjects. Significantly global changes emerged in the right mammillary body (HF 1.18 ± 1.13 vs control 0.52 ± 0.74; P = .024), right hippocampus (HF 1.53 ± 0.94 vs control 0.80 ± 0.86; P = .005), and left frontal cortex (HF 1.76 ± 1.03 vs control 1.24 ± 0.77; P = .034). Comparison of the visual method with specialized MRI techniques corroborates right hippocampal and left frontal cortical, but not mammillary body, tissue changes.ConclusionsVisual examination of brain MRI can detect damage in HF in areas regulating depression and executive function, including the right hippocampus and left frontal cortex. Visual MRI assessment in HF may facilitate evaluation of injury to these structures and the assessment of the impact of potential treatments for this damage. 相似文献
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Emmanouil S. Brilakis MD PhD Michael Lee MD Julinda Mehilli MD Konstantinos Marmagkiolis MD Josep Rodes-Cabau MD Rajesh Sachdeva MD Anna Kotsia MD George Christopoulos MD Bavana V. Rangan BDS MPH Atif Mohammed MD Subhash Banerjee MD 《Current treatment options in cardiovascular medicine》2014,16(5):1-12
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Rinkesh K. Bansal Narendra S. Choudhary Saurabh K. Patle Amit Agarwal Gagandeep Kaur Haimanti Sarin Rajesh Puri 《Indian journal of gastroenterology》2018,37(2):108-112