LitCovid-sentences  

PMC:7594251 / 15762-17377 JSONTXT 6 Projects

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Id Subject Object Predicate Lexical cue
T111 0-6 Sentence denotes 2.1.2.
T112 7-17 Sentence denotes 1D 13C-NMR
T113 18-147 Sentence denotes Compared with 1H, 13C has a much higher chemical shift dispersion (~200 ppm), however the natural abundance of 13C is low (1.1%).
T114 148-312 Sentence denotes Additionally, the gyromagnetic ratio is ~4 times weaker than 1H and therefore 13C spectra are far more difficult to obtain especially for less concentrated samples.
T115 313-774 Sentence denotes There are some polarization transfer techniques such as Distortionless Enhancement by Polarization Transfer (DEPT) or Insensitive Nuclei Enhanced by Polarization Transfer (INEPT), which can enhance signal intensity by starting the magnetization on a higher sensitivity and abundance proton and then transferring magnetization to the less sensitive carbon nuclei for subsequent direct detection [111], but this requires additional hardware and acquisition times.
T116 775-858 Sentence denotes The use of 1D 13C in drug design studies was illustrated by Tsujimoto et al. [112].
T117 859-1006 Sentence denotes The goal of the study was to examine if a metabolomics approach based on 1H and 13C offers significant improvements when comparing potential drugs.
T118 1007-1181 Sentence denotes The authors prepared a total of 40 samples with five different citrus-type crude drugs (kijitsu, tohi, chimpi, kippi and seihi) and measured 1D 1H and 1D 13C for each sample.
T119 1182-1454 Sentence denotes While 1H-NMR spectra allowed the identification of three compounds (naringin, sucrose, and β-glucose), using 13C-NMR allowed unambiguous identification of eight additional compounds (naringin, neohesperidin, α- and β-glucose, sucrose, limonene, narirutin, and synephrine).
T120 1455-1615 Sentence denotes The added signal resolution from 13C-NMR spectra allowed researchers to obtain better structural information about the compounds than from 1H-NMR spectra alone.