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631.
Mercury(Hg), mainly in cinnabar species, has been used in medicine for thousands of years in China, and worldwide concern has been raised on its toxicity. In this work, the amount of bioaccessible mercury in 16 Chinese patent medicines(CPMs) was measured by using an in vitro simulated digestion system, consisting of simulated gastric and intestinal fluid, to investigate the bioavailability of mercury in CPMs and evaluate its potential risk to human health. Total mercury and mercury in the gastrointestinal extracts were measured by inductively coupled plasma mass spectrometry(ICP-MS). The levels of total Hg in 16 CPMs ranged from not detected to 11.89 mg/g, with a mean value of 1.13 mg/g, while the extractable Hg ranged from not detected to 4.37 μg/g, with a mean value of 0.42 μg/g.Mercury bioaccessibility varied significantly in the investigated CPMs, depending on the ingredient. Compared to the CPMs without cinnabar(2.5%–30.9%), the percentage of mercury in the gastrointestinal supernatants for CPMs with cinnabar was quite a bit lower(0.037%). By comparing with the Food and Agricultural Organization/World Health Organization Joint Expert Committee on Food Additives(FAO/WHO) safety guideline, the average daily intake dose(ADD) of Hg in the medicines was then calculated to access the risk of mercury to human health from taking CPMs. 相似文献
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Uniparental disomy (UPD) is an uncommon chromosome condition, but UPD involving chromosome 21 is rarely reported. We reported here a case who had first trimester screening test for Down syndrome, chorionic villus sampling for fetal karyotyping, quantitative fluorescence polymerase chain reaction (QF-PCR), as well as non-invasive prenatal testing (NIPT) by maternal plasma sequencing. There were discordant results between fetal karyotyping and NIPT due to UPD 21combined with confined placental mosaicism of trisomy 21. This demonstrated that it is possible to detect placental mosaicism by NIPT, but further studies are required to confirm its sensitivity. Therefore, all positive NIPT results must be confirmed by conventional invasive test and karyotyping. QF-PCR has the additional benefit in diagnosing UPD. © 2013 John Wiley & Sons, Ltd. 相似文献
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本文描述了六安地震台TJ-Ⅱ体应变仪钻孔的地质构造特点与钻孔岩芯物理特性,介绍了TJ-Ⅱ体应变仪在六安台运行情况。通过六安台TJ-Ⅱ一年观测资料的同震效应与区域前兆异常分析,初步探讨了地下形变对大别山区未来中强震预测研究的实际意义。 相似文献
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研究了Fenton氧化技术在改善污泥脱水性能方面的效果,以污泥比阻和毛细吸水时间来表征污泥的脱水性能,探讨了体系的pH和反应时间对污泥脱水性能的影响以及Fenton氧化对污泥溶解性物质(SCOD+多聚糖+蛋白质)含量的影响研究表明,Fenton氧化能够明显改善污泥的脱水性能。在体系的pH=3时,反应1h后,Fenton氧化处理后污泥的CST从处理前的130.9s减少到19.7s,降幅85%;污泥SRF从处理前的3.58×108 s2/g降低到1.05×107 s2/g,降幅97%。同体系处理污泥SCOD、上清液中多聚糖和蛋白质的含量分别增加了3.7倍、2.6倍和1.5倍。 相似文献
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ZrO2-Al2O3 composite oxides and supported Ni catalysts were prepared, and characterized by N2 adsorption/desorption, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques. The catalytic performance and carbon deposition was also investigated. This mesoporous composite oxide is shown to be a promising catalyst support. An increase in the catalytic activity and stability of methane and carbon dioxide reforming reaction was resulted from the zirconia addition, especially at 5wt% ZrO2 content. The Ni catalyst supported ZrO2-Al2O3 has a strong resistance to sintering and the carbon deposition in a relatively long-term reaction. 相似文献