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991.
Design of high-power,broadband 180° pulses and mixing sequences for fast MAS solid state chemical shift correlation NMR spectroscopy 总被引:2,自引:2,他引:0
Christian Herbst Jirada Herbst Anika Kirschstein Jörg Leppert Oliver Ohlenschläger Matthias Görlach Ramadurai Ramachandran 《Journal of biomolecular NMR》2009,43(1):51-61
An approach for the design of high-power, broadband 180° pulses and mixing sequences for generating dipolar and scalar coupling
mediated 13C–13C chemical shift correlation spectra of isotopically labelled biological systems at fast magic-angle spinning frequencies
without 1H decoupling during mixing is presented. Considering RF field strengths in the range of 100–120 kHz, as typically available
in MAS probes employed at high spinning speeds, and limited B
1 field inhomogeneities, the Fourier coefficients defining the phase modulation profile of the RF pulses were optimised numerically
to obtain broadband inversion and refocussing pulses and mixing sequences. Experimental measurements were carried out to assess
the performance characteristics of the mixing sequences reported here. 相似文献
992.
993.
994.
M Ramachandran C N Nair E C Abraham 《Biochemical and biophysical research communications》1987,147(1):56-64
A four-fold increase in the binding of 3H-PDBu by red cell membrane ghosts isolated from sickle red cells compared to that from normal controls is presented. Phosphorylation studies with gamma-32P-ATP indicate a similar (two to three-fold) increase in the radiolabelling of the acid-precipitable membrane proteins in sickle red cells. When red cells were loaded with Ca2+ using Ionophore A23187, both normal and sickle red cells enhanced their phosphorylation and sickle red cells to a greater extent than normal red cells. Polyacrylamide slab gel electrophoretic separation of the phosphoproteins and autoradiography also reveal phosphorylation, predominantly of protein bands 3, 4.1 and 4.9 which are known in the red cells as specific substrates for the PDBu receptor, protein kinase C. These results indicate that membrane association of protein kinase C in sickle red cells is increased, possibly as a consequence of the pathological change in their ability to accumulate intracellular calcium. 相似文献
995.
996.
Jhansi Nathan Rabiathul Shameera Arunkumar Ramachandran 《Journal of biochemical and molecular toxicology》2023,37(5):e23320
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) originated in Wuhan, China, in early December 2019 is a censorious global emergency after World War II. Research on the coronavirus uncovered essential information that aided in the development of the vaccine, and specific coronavirus disease 2019 (COVID-19) vaccines were later developed and were approved for usage in humans. But then, mutations in the coronavirus gave rise to new variants and questioned the vaccine's efficacy against them. On the other hand, the investigation of traditional medicine was also on its path to find a novel outcome against COVID-19. On a comparative analysis between India and the United States, India had low death rate and high recovery rate than the latter. The dietary regulation of immunity may be the factor that makes the above difference. The immunity gained from the regular diet of Indian culture nourishes Indian people with essential phytochemicals that support immunity and metabolism. Dietary phytochemicals or nutraceuticals possess antioxidant, anti-inflammatory, and anticancer properties, out of which our concern will be on immune-boosting phytochemicals from our daily nutritional supplements. In several case studies, dietary substance like lemon, ginger, and spinach was reported in the recovery of COVID-19 patients. Thus in this review, we discuss coronavirus and its available variants, vaccines, and the effect of nutraceuticals against the coronavirus. Further, we denote that the immunity of the Indian population may be high because of their diet, which adds natural phytochemicals to boost their immunity and metabolism. 相似文献
997.
Eroshenko Nikolai Ramachandran Rukmani Yadavalli Vamsi K Rao Raj R 《Journal of biological engineering》2013,7(1):1-16
There is growing demand for robust DNA assembly strategies to quickly and accurately fabricate genetic circuits for synthetic biology. One application of this technology is reconstitution of multi-gene assemblies. Here, we integrate a new software tool chain with 2ab assembly and show that it is robust enough to generate 528 distinct composite parts with an error-free success rate of 96%. Finally, we discuss our findings in the context of its implications for biosafety and biosecurity. 相似文献
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999.
A method is described for the synthesis of cyclic thionocarbonates of 1-O-alkyl glycerols in quantitative yield. These derivatives of glycerol ethers can be quantitated by UV absorbance, analyzed by gas-liquid chromatography, or quantitatively converted to allyl alkyl ethers for gas-chromatographic analysis. 相似文献
1000.