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381.
Recently, adulterated supplements with phosphodiesterase-5 inhibitors (PDE-5i) have frequently observed. New synthetic analogues obtained from the chemical modification of parent compounds are frequently found in illicit products despite continuous efforts to inspect for these adulterants. A rapid and accurate method based on quadrupole-Orbitrap mass spectrometry was developed for simultaneously confirming and quantifying 85 PDE-5i and derived analogues present in illicit products for erectile dysfunction (ED). Common ions of PDE-5i according to their similar structures were proposed based on MS/MS fragmentations. These common ions could be an important diagnosis of their presence targets or new emerging analogues in supplements. Several validation parameters were employed, resulting in a limit of detection and quantification of 0.09–8.55 ng/mL and 0.24–17.10 ng/mL, respectively. The linear correlation coefficient (r2) was higher than 0.995, and mean recoveries of target compounds were in the range of 82–118%. A total of 187 illicit products, obtained from on/offline markets over a period of 3 years (2015–2017), were screened by the established method. Approximately 53% of them were adulterated with PDE-5i or derived analogues at concentrations of 0.1–726.0 mg/g in the illicit products. In the interests of public health, this study describes a rapid and accurate method to determine PDE-5i and new emerging analogues in adulterated products. 相似文献
382.
Asian Journal of Criminology - Numerous studies have analyzed the relationship between disorder and fear of crime, but few have focused on the impact of policing against disorder on fear of crime.... 相似文献
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Asia Europe Journal - This paper aims to probe how leaders of Brexit (Nigel Farage) and Bremain (David Cameron) camps communicated with the UK public via Facebook fan pages. This study employed two... 相似文献
385.
The increasing suicide rate in South Korea in recent decades was found to be associated with measures of social integration/regulation (birth and divorce rates). 相似文献
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Lee JS Han EY Lee SY Kim EM Park YH Lim MA Chung HS Park JH 《Forensic science international》2006,161(2-3):209-215
Organic impurities of methamphetamine may show different patterns by synthesis. In the present study, we tried to find the impurities reflecting the conditions of synthesis by comparing impurity patterns of the methamphetamine samples synthesized by different methods. Sixteen methamphetamine samples were synthesized from ephedrine and pseudoephedrine by the three different manufacturing methods of Emde, Nagai and Moscow. The synthesized samples were extracted with ethyl acetate containing four internal standards, and the patterns of the organic impurities were investigated by GC-MS and GC-FID . Through the investigation, we found 10 peaks appearing in the latter part of GC chromatograms are characteristic to synthesis. The areas of the selected peaks were converted to the variables suitable for the statistical calculation, and the synthesized samples could be classified into four groups through the resultant cluster analysis. 相似文献
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