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81.
目的 制备高纯度3,5-O-二咖啡酰基奎宁酸,并评价其对人宫颈癌HeLa细胞的抗增殖活性。方法 采用柱色谱提取法和中压液相色谱法从奇蒿花中分离、纯化得到高纯度的3,5-O-二咖啡酰基奎宁酸。采用MTT法评价该化合物对人宫颈癌HeLa细胞的体外抗增殖活性。结果 柱色谱提取的提取率和中压液相色谱法的回收率分别为99.0%,61.2%,总回收率为54.0%。随着3,5-O-二咖啡酰基奎宁酸浓度升高,HeLa细胞存活率下降,细胞形态损伤增加,受试药物的IC50值为26.5µg·mL-1结论 本研究提供了一种简单、高效、节能的3,5-O-二咖啡酰基奎宁酸制备方法。3,5-O-二咖啡酰基奎宁酸对HeLa细胞具有一定的体外抗增殖活性。  相似文献   
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In 1984, interstitial cystitis (IC) was considered a rare psychosomatic disorder in post-menopausal women. In 2014, the Interstitial Cystitis Association of America (ICA) celebrated its 30th anniversary. We’ve come a long way since 1984 and great progress has been made. IC is now recognized as a condition that afflicts both men and women of all ages, including children and teenagers. It is not a psychiatric disorder. Though it was once thought to be an orphan disease (defined as affecting less than 200,000 people), we now know that there are millions of women and men who suffer from IC/BPS (bladder pain syndrome). In looking back over this period, there were seven key reasons why the ICA became so successful: an extremely dedicated ICA staff, Board of Directors and volunteers; a very strong Medical Advisory Board and participation of many other urologists from across the country and around the world; cooperation of the media; epidemiological studies; the ICA’s Pilot Research Program; our representation in Congress; and a strong working partnership with the National Institutes of Health (NIH). Our history may prove useful to other advocacy groups.  相似文献   
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Background: The current disadvantages (high cost, toxicity, resistance) of chemotherapy for gastric cancer opted people for alternative therapy from natural source. Curcumin (natural product) possess multiple biological activities but low bio-availability limits their uses as therapeutic. The Nano-formulation of curcumin increased the bioavailability and productivity of anti-cancer and anti-bacterial properties. The present study was initiated to determine the anti-cancer and anti-bacterial effect of Nano curcumin against gastric cancer and H. pylori. Methods: Curcumin loaded PLGA nanoparticles (CUR-NPs) was prepared by single emulsion solvent evaporation method. The MIC were determined using agar dilution method to find the anti-H. Pylori activity of Nano curcumin. The cytotoxicity of Nano curcumin was evaluated by MTT assay and the apoptotic effect (cell cycle arrest and morphology change) was shown by PI staining and microscopy. Results: The MIC of nanocurcumin and curcumin for all four H. pylori strains were 8 µg/ml and 16 µg/ml respectively. The inhibition rate of gastric cancer cells after treatment with curcumin was increased from 6% to 67% for 24h, from 8% to 75% for 48h, from 10% to 83% for 72h. In case of nanocurcumin, the inhibition rate increased from 7% to 69% for 24h, 11% to 87% for 48h and 16% to 97% for 72h. The IC50 of curcumin and Nano-curcumin were 24.20 µM and 18.78 µM respectively for 72 h. The population of cells in sub-G0 population increased from 4.1% in the control group to 24.5% and 57.8% when treated with curcumin and nanocurcumin respectively. After 72h of treatment with nanocurcumin, the apoptotic cells population increased as compared to native curcumin treated cells. Conclusion: The Nano curcumin might be used as a potential therapeutics against gastric cancer and H. Pylori. There is need of further in vivo study in order to validate CUR-NPs activity.  相似文献   
86.
近几十年来,阴、阳离子检测方法的发展非常迅速,检测方法有了较大的改进,同时离子种类得到很大的丰富。根据不同的药物分析目的可选择不同的检测方法,以取得最好的检测精度和灵敏度。简要地介绍了用于检测药物中常用的阴、阳离子的比浊法、比色法、滴定法、离子选择电极法、可见-紫外分光光度法、原子吸收分光光度法与色谱法等分析方法,并对今后的研究方向进行了展望。  相似文献   
87.
This report discusses a selection of the most relevant articles on cardiac arrhythmias and pacing published in 2013. The first section discusses arrhythmias, classified as regular paroxysmal supraventricular tachyarrhythmias, atrial fibrillation, and ventricular arrhythmias, together with their treatment by means of an implantable cardioverter defibrillator. The next section reviews cardiac pacing, subdivided into resynchronization therapy, remote monitoring of implantable devices, and pacemakers. The final section discusses syncope.  相似文献   
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Nelarabine is one of the newer and novel drugs approved by the USA Food and Drug Administration for treatment of relapsed and resistant acute lymphoblastic leukemia. Although there are a few accounts of the neurologic toxicity of nelarabine in the oncological literature, it has never been discussed from a radiologic stand point to our knowledge. We describe a case of nelarabine-induced myelopathy and review the existing literature in an attempt to characterize the MRI features helpful in making an early diagnosis of this elusive entity.  相似文献   
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Fetal alcohol spectrum disorders represent a wide range of symptoms associated with in utero alcohol exposure. Animal models of FASD have been useful in determining the specific neurological consequences of developmental alcohol exposure, but the mechanisms of those consequences are unclear. Long-lasting changes to the epigenome are proposed as a mechanism of alcohol-induced teratogenesis in the hippocampus. The current study utilized a three-trimester rodent model of FASD to examine changes to some of the enzymatic regulators of the epigenome in adolescence. Combined pre- and post-natal alcohol exposureresulted in a significant increase in DNA methyltransferase activity (DNMT), without affecting histone deacetylase activity (HDAC). Developmental alcohol exposure also caused a change in gene expression of regulators of the epigenome, in particular, DNMT1, DNMT3a, and methyl CpG binding protein 2 (MeCP2). The modifications of the activity and expression of epigenetic regulators in the hippocampus of rodents perinatally exposed to alcohol suggest that alcohol's impact on the epigenome and its regulators may be one of the underlying mechanisms of alcohol teratogenesis.  相似文献   
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