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61.
气相色谱法测定马应龙麝香痔疮膏中龙脑的含量 总被引:6,自引:2,他引:6
目的:建立马应龙麝香痔疮膏中龙脑的含量测定方法.方法:气相色谱法,2 m×3 mm不锈钢柱,15%丁二酸二乙二醇聚酯(DEGS)Chromsorb W-AW(80~100目),柱温105℃,进样口温度250℃,FD检测器,载气为氮气.结果:平均回收率为99.92%(n=6),RSD为0.65%.结论:本法简便高效,结果准确可靠,可用于本品的质量控制. 相似文献
62.
建立了毛细管气相色谱法测定兰索拉唑中甲醇、丙酮、乙腈、氯仿的残留量.采用RTX-50毛细管柱,程序升温.各溶剂检测限分别为18、50.4、1.46和0.4ng,平均回收率分别为102.3%、100.4%、101.8%和1013%. 相似文献
63.
八宝眼粉质量标准的研究 总被引:2,自引:1,他引:2
目的:建立八宝眼粉的质量控制方法.方法:采用化学反应和薄层色谱法(TLC)鉴别方中炉甘石、人工牛黄、冰片;采用气相色谱法(GC)测定冰片的含量.结果:鉴别效果满意;冰片在0.09808~0.78464 μg范围内呈良好的线性关系,平均加样回收率为101.5%,RSD=1.40%(n=5).结论:本方法简便、快速准确,可作为该制剂质量控制方法. 相似文献
64.
顶空气相色谱法检测百乐眠胶囊中树脂残留物 总被引:6,自引:2,他引:6
建立气相色谱法检测百乐眠胶囊中树脂残留物的方法.采用气相色谱法对百乐眠胶囊中苯、甲苯、二甲苯、正己烷、苯乙烯、1,4-二乙苯的残留量进行检测,气相色谱条件为:色谱柱HP-5,载气为高纯氮气,柱前压为10Psi,气化室温度200℃,柱温60℃(5min),以30℃*min-1的速率升至90℃(3.5min),再以30℃*min-1的速率升至140℃(4min),最后以30℃*min-1的速率升至190℃(3min),检测器为FID,温度为220℃.正己烷在1.815~29.060μg*ml-1,苯在0.0128~0.1966μg*ml-1内,甲苯在0.685~11.125μg*ml-1内,二甲苯在1.698~27.170μg*ml-1内,苯乙烯在1.695~27.125μg*ml-1内,1,4-二乙苯在1.699~27.140μg*ml-1内均有良好的线性关系,相关系数分别为0.9996、0.9991、0.9996、0.9998、0.9966、0.9980.本法简便、快速、准确度高,适于测定百乐眠胶囊中树脂残留物,可作为百乐眠胶囊的质量监控方法. 相似文献
65.
广藿香挥发油气相色谱指纹图谱再研究 总被引:10,自引:0,他引:10
目的:建立广藿香挥发油的特征指纹图谱,用于广藿香的品质控制及产地鉴别.方法:采用GC法对高要、石牌、吴川、遂溪、雷州及海南万年产广藿香挥发油进行GC图谱的比较分析.结果:以11个共有峰为评价指标,GC分析色谱条件的精密度、稳定性、重复性良好;同产地、不同采收期广藿香的主成分基本相同,但含量有差异;不同产地的广藿香其各组分的含量有较大的差异.结论:以11个共有峰作为广藿香挥发油特有的指纹图谱,以广藿香酮与广藿香醇的峰面积比值作为鉴别不同产地的广藿香的指标参数,建立了可用于广藿香道地性鉴别及品质评价的气相色谱指纹图谱标准. 相似文献
66.
Chi-Wei Lee Yu-Ying Chao Jentaie Shiea Jheng-Heng Shen Hei-Hwa Lee Bai-Hsiun Chen 《The American journal of emergency medicine》2018,36(3):530.e1-530.e5
A 25-year-old man suffered from consciousness change was sent to our emergency department by friends who reported that they were not sure what had happened to him. Physical examination revealed bilateral pupils dilatation, lethargy, slurred speech, and ataxia. Computer-aided tomographic scan of the brain revealed no definite evidence of intracranial lesions. Routine laboratory tests revealed total physiological turmoil. Despite immediate commencement of aggressive treatment, the patient's condition deteriorated long before the traditional drug screen provided an answer for the identities of the multiple drugs overdose. It ended up with the need for cardiopulmonary resuscitation, but in vain. At the end of the tragic event, under the suggestion of a colleague, a portion of the patient's urine specimen was sent to our university esoteric laboratory for rapid analysis by means of a newly-developed thermal desorption-electrospray ionization-mass spectrometry. Ketamine, 3,4-methylenedioxymethamphetamine, and 3,4-methylenedioxyamphetamine were identified in the urine sample within 30 s. Conventional toxicological testing techniques like gas chromatography–mass spectrometry or liquid chromatography-mass spectrometry are currently used for identifying abused drugs. One concern is their time-consuming sample pretreatment which leads to relatively low efficiency in terms of turnaround time for revealing the identity of the consumed drugs particularly when the patients are severely overdosed. We learned a lesson from this case that a more efficient toxicological identification technique is essential to expedite the process of emergency care when the patients are so heavily overdosed that they are under critical life-threatening conditions. 相似文献
67.
68.
Yueting Deng Chen Huang Jingyue Su Chen-Wei Pan Chaofu Ke 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(2):382-395
AimEssential hypertension (EH) is one of the most important public health problems worldwide. However, the pathogenesis of EH is unclear and early diagnostic methods are lacking. Metabolomics demonstrates great potential for biomarker discovery and the mechanistic exploration of metabolic diseases.Data synthesisThis review included human and animal metabolomics studies related to EH in the PubMed and Web of Science databases between February 1996 and May 2020. The study designs, EH standards, and reported metabolic biomarkers were systematically examined and compared. The pathway analysis was conducted through the online software MetaboAnalyst 4.0.Twenty-two human studies and fifteen animal studies were included in this systematic review. There were many frequently reported biomarkers with consistent trends (e.g., pyruvate, lactic acid, valine, and tryptophan) in human and animal studies, and thus had potential as biomarkers of EH. In addition, several shared metabolic pathways, including alanine, aspartate, and glutamate metabolism, aminoacyl-tRNA biosynthesis, and arginine biosynthesis, were identified in human and animal metabolomics studies. These biomarkers and pathways, closely related to insulin resistance, the inflammatory state, and impaired nitric oxide production, were demonstrated to contribute to EH development.ConclusionsThis study summarized valuable metabolic biomarkers and pathways that could offer opportunities for the early diagnosis or prediction of EH and the discovery of the metabolic mechanisms of EH. 相似文献
69.
BackgroundMultidisciplinary management of patients with locally advanced gastric cancer (LAGC) remains unstandardized worldwide. We performed a systemic review to summarize the advancements, regional differences, and current recommended multidisciplinary treatment strategies for LAGC.MethodsEligible studies were identified through a comprehensive search of PubMed, Web of Science, Cochrane Library databases and Embase. Phase 3 randomized controlled trials which investigated survival of patients with LAGC who underwent gastrectomy with pre-/perioperative, postoperative chemotherapy, or chemoradiotherapy were included.ResultsIn total, we identified 11 studies of pre-/perioperative chemotherapy, 38 of postoperative chemotherapy, and 14 of chemoradiotherapy. In Europe and the USA, the current standard of care is perioperative chemotherapy for patients with LAGC using the regimen of 5-FU, folinic acid, oxaliplatin and docetaxel (FLOT). In Eastern Asia, upfront gastrectomy and postoperative chemotherapy is commonly used. The S-1 monotherapy or a regimen of capecitabine and oxaliplatin (CapOx) are used for patients with stage II disease, and the CapOx regimen or the S-1 plus docetaxel regimen are recommended for those with stage III Gastric cancer (GC). The addition of postoperative radiotherapy to peri- or postoperative chemotherapy is currently not recommended. Additionally, clinical trials testing targeted therapy and immunotherapy are increasingly performed worldwide.ConclusionsRecent clinical trials showed a survival benefit of peri-over postoperative chemotherapy and chemoradiotherapy. As such, this strategy may have a potential as a global standard for patients with LAGC. Outcome of the ongoing clinical trials is expected to establish the global standard of multidisciplinary treatment strategy in patients with LAGC. 相似文献
70.
Acetone cyanohydrin (ACH) is a readily available source of cyanide and is widely used in basic and applied sciences. In toxicology, ACH is classified as extremely hazardous as it readily decomposes on contact with water, with the potential rapid release of highly toxic hydrogen cyanide (HCN). We report the case of a young woman found dead from the intentional ingestion of ACH and citalopram, an antidepressant of the selective serotonin reuptake inhibitor class. The autopsy findings included bright reddish-purple hypostasis and mild pulmonary edema. As ACH can decompose to acetone and HCN, we quantified the concentration of each compound and thiocyanate separately in various body fluids and organs and determined their whole-body distributions by using gas chromatography–mass spectrometry (GC–MS). We observed high concentrations of both acetone and cyanide in the blood (0.63 mg/mL and 17.99 mM, respectively) and gastric contents (9.76 mg/mL and 472.44 mM). The whole-body distributions of acetone and cyanide were similar (i.e., the concentration of each compound was the highest in the lung, followed by the heart, and then the liver). Our results suggest that not only the route of administration but also the dose taken could greatly affect the body distributions of cyanide in humans. In addition, as toxicological screening detected citalopram, which was not prescribed to the deceased, we performed a chiral analysis by using liquid chromatography–tandem mass spectrometry (LC–MS/MS). We determined that only (S)-citalopram was ingested antemortem; its concentration was 0.36 μg/mL, which is in the toxic range. 相似文献