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991.
某蓄电池厂二十一年铅浓度与铅中毒的动态分析 总被引:4,自引:0,他引:4
调查分析了某蓄电池厂二十一年铅浓度与铅中毒的关系,结果表明空气中铅浓度与铅中毒病人正相关,r=0.67,P〈0.05,说明空间空气中铅浓度升高,铅中毒病人有可能增加,反之减少。直线回归方程为y=6.35+1.5598x,P〈0.05,回归系数也说明同样道理。通过不同工种铅浓度与铅中毒病人的关系可以看出在车间空气中铅浓度相对不高的情况下其发病率高的主要原因是接触时间较长,从而说明接触时间也是不可忽视 相似文献
992.
993.
食用植物油中甘油三酯色谱分析方法研究进展 总被引:1,自引:0,他引:1
甘油三酯 (TAGs) 是植物油的主要成分(占95%~98%),对植物油的性质有着重要的影响。对其结构组成的分析有助于监控食用植物油质量,保障植物油食用安全。由于甘油骨架上可以结合的脂肪酸很多,导致甘油三酯的种类十分庞大,且一般天然油脂中的甘油三酯不仅物理化学性质非常接近,同时还存在大量的同分异构体和位置异构体。因此甘油三酯的分析是一项非常有挑战性的工作。该文对各类色谱分析技术在食用油中甘油三酯分析方面的应用进行了综述,评述了各方法的优缺点,并对指纹图谱技术和化学计量学方法在植物油鉴定中的应用进行了介绍。 相似文献
994.
超高效液相色谱法同时鉴定育发化妆品中17种植物提取物标识成分 总被引:1,自引:0,他引:1
建立了同时鉴定育发化妆品中芍药苷、羟基红花黄色素A、毛蕊异黄酮葡萄糖苷、阿魏酸等17种植物提取物标识成分的超高效液相分析方法。不同基质的样品经80%甲醇溶液涡旋振荡、超声提取及Na Cl法破乳后,提取液经高速离心处理。选用Waters ACUITY UPLC CSH C18反相色谱柱(50 mm×2.1 mm,1.7μm),以甲醇/0.05%H3PO4为流动相,梯度洗脱,然后采用二极阵列管检测器(PDA)进行测定。考察了方法的灵敏度、线性范围、回收率、日内和日间精密度。在本方法条件下,17种标识功效成分在0.2~25 mg/L的浓度范围内呈良好线性关系,相关系数均大于0.999;方法检出限为0.3~1.5 mg/kg,方法定量限为1.0~4.0 mg/kg。样品的回收率为93.5%~105.0%,日内精密度(n=6)为0.4%~4.5%,日间精密度(n=6)为0.8%~4.6%。本方法简单、快速、准确,已成功用于实际样品中17种标识功效成分的鉴定检测。 相似文献
995.
高效液相色谱-串联质谱法检测瓜果中的4种植物生长调节剂的残留量 总被引:1,自引:0,他引:1
建立了用于测定瓜果中多效唑、氯吡脲、异戊烯腺嘌呤和6-苄氨基嘌呤等4种植物生长调节剂残留量的高效液相色谱-串联质谱分析方法。样品用乙腈提取,经阳离子交换固相萃取柱净化后,用Agilent XDB-C18色谱柱分离,以5 mmol/L乙酸铵溶液和含0.1%(体积分数)甲酸的乙腈溶液为流动相进行梯度洗脱。质谱采用电喷雾正离子(ESI+)模式电离,多反应监测(MRM)模式检测,基质匹配标准溶液外标法定量。4种植物生长调节剂在各自的范围内线性很好,相关系数均大于0.999。选取了黄瓜和苹果作为代表性基质进行添加回收试验,定量限(信噪比大于10)在0.04~1.35 μg/kg之间,检出限(信噪比大于3)在0.01~0.41 μg/kg之间,在3个添加水平下回收率范围为81.0%~93.3%,相对标准偏差(RSDs)为3.5%~9.5%。该方法的灵敏度、准确度和精密度均符合农药残留测定的技术要求,适用于瓜果中这4种植物生长调节剂残留量的检测。 相似文献
996.
Ftima A. R. Mota Sarah A. P. Pereira Andr R. T. S. Araújo Beatriz Gulln Marieta L. C. Passos Maria Lúcia M. F. S. Saraiva 《Molecules (Basel, Switzerland)》2022,27(6)
The aim of this study is the development of an automated method for myeloperoxidase activity evaluation and its application in testing the inhibitory action of different plant extracts on the activity of the enzyme. This enzyme has its concentration increased in inflammatory and infectious processes, so it is a possible target to limit these processes. Therefore, an automatic sequential in-jection analysis (SIA) system was optimized and demonstrated that it is possible to obtain results with satisfactory accuracy and precision. With the developed method, plant extracts were studied, as promising candidates for MPO inhibition. In the group of selected plant extracts, IC50 values from 0.029 ± 0.002 mg/mL to 35.4 ± 3.5 mg/mL were obtained. Arbutus unedo L. proved to be the most inhibitory extract for MPO based on its phenolic compound content. The coupling of an automatic SIA method to MPO inhibition assays is a good alternative to other conventional methods, due to its simplicity and speed. This work also supports the pharmacological use of these species that inhibit MPO, and exhibit activity that may be related to the treatment of infection and inflammation. 相似文献
997.
Monoterpenes make up the largest group of plant secondary metabolites. They can be found in numerous plants, among others, the Lamiaceae family. The compounds demonstrate antioxidative, antibacterial, sedative and anti-inflammatory activity, hence, they are often employed in medicine and pharmaceuticals. Additionally, their fragrant character is often made use of, notably in the food and cosmetic industries. Nevertheless, long-lasting studies have revealed their toxic properties. This fact has led to a detailed analysis of the compounds towards their side effects on the human organism. Although most are safe for human food and medical applications, there are monoterpene compounds that, in certain amounts or under particular circumstances (e.g., pregnancy), can cause serious disorders. The presented review characterises in vitro and in vivo, the toxic character of selected monoterpenes (α-terpinene, camphor, citral, limonene, pulegone, thujone), as well as that of their original plant sources and their essential oils. The selected monoterpenes reveal various toxic properties among which are embryotoxic, neurotoxic, allergenic and genotoxic. It is also known that the essential oils of popular plants can also reveal toxic characteristics that many people are unaware of. 相似文献
998.
Boron chemistry has been intensively studied in the recent past. Although the study of the interactions between transition‐metal ions and the phenyl methylene ester derivatives of hydrazine carbodithioic acids has been carried out on a long period, particularly via the formation of adducts, their interaction of Main Group metal ions and the formation of their coordination complexes are subjects of current interest. We have synthesized and isolated a variety of complexes of phenyl dihydroxyborane with substituted dithiocarbazates. The benzene‐soluble, high‐molecular‐weight complexes have been characterized using a wide range of analytical and spectroscopic techniques. The pathogenicity of microbial infections associated with the complexes have been subjected to a variety of biointeraction studies and the results are discussed. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
999.
Yichen Wang Mubasher Hussain Zhenbin Jiang Zhaohong Wang Jing Gao Fengxian Ye Runqian Mao He Li 《Molecules (Basel, Switzerland)》2021,26(24)
Agarwood is a highly valuable fragrant wood of Aquilaria spp. (Thymelaeaceae) which has been widely utilized in traditional medicine, religious rites, and cultural activities. This study summarizes a review on the identification of Aquilaria cultivars, volatile and non-volatile phytochemicals, pharmacological uses, and agarwood grading system to determine its quality, and different agarwood induction methods. Due to the highly demanding and depleted natural resources, the research on agarwood is still insufficient, and it has broad research and development prospects in many industries. However, due to the significant scientific nature of agarwood application, developing high-quality products and drugs from agarwood have become highly important, while no one has discussed in detail the phytochemicals uses and provided a summary until now. The main phytochemicals of agarwood include terpenoids, dominated by sesquiterpenes. For centuries, terpenoids have been used in traditional Chinese medicine and have been shown to possess various pharmacological properties, including bacteriostatic, antibacterial, sedation, analgesia, anti-inflammation, anti-asthmatic, hypoglycemic, antidepressant, and many others. Alongside biological activity screening, phytochemical advances and pharmacological research have also made certain progress. Therefore, this review discusses the research progress of agarwood in recent years and provides a reference basis for further study of Aquilaria plants and agarwood. 相似文献
1000.
Kateryna Prysiazhniuk Oleksandr P. Datsenko Oleksandr Polishchuk Stanislav Shulha Oleh Shablykin Yelyzaveta Nikandrova Kateryna Horbatok Iryna Bodenchuk Petro Borysko Dmytro Shepilov Iryna Pishel Vladimir Kubyshkin Pavel K. Mykhailiuk 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(9):e202316557
The spiro[3.3]heptane core, with the non-coplanar exit vectors, was shown to be a saturated benzene bioisostere. This scaffold was incorporated into the anticancer drug sonidegib (instead of the meta-benzene), the anticancer drug vorinostat (instead of the phenyl ring), and the anesthetic drug benzocaine (instead of the para-benzene). The patent-free saturated analogs obtained showed a high potency in the corresponding biological assays. 相似文献