原子吸收光谱法测定浓海水中的微量锂     

杨淑清  竺柏康  王路辉 《浙江水产学院学报》2012,(2):153-156

采用空气-乙炔火焰原子吸收光谱法测定浓海水中微量金属锂离子时,干扰主要来自浓海水中共存的高浓度的阳离子。探讨了共存的主要阳离子对锂离子测定的影响,并分析了消除高浓度阳离子干扰的方法。结果表明：Ca2＋和Mg2＋是主要干扰元素,可以采用标准加入法消除共存的高浓度阳离子的干扰;锂在0.13～1.92 mg/L范围内线性关系良好,平均回收率为99.62%。  相似文献   

Antiproliferative activity of Saponaria vaccaria constituents and related compounds     

Balsevich JJ  Ramirez-Erosa I  Hickie RA  Dunlop DM  Bishop GG  Deibert LK 《Fitoterapia》2012,83(1):170-181

Total methanolic extracts of Saponaria vaccaria seed derived from several varieties, as well as various purified components obtained through successive chromatographic separations of total extracts were evaluated for their growth inhibitory activity in WiDr (colon), MDA-MB-231 (breast), NCI-417 (lung) and PC-3 (prostate) human cancer cells as well as the non-tumorigenic fibroblast BJ (CRL-2522) cell line using MTT colorimetric assay. Purified bisdesmosidic saponins segetoside H and I were further examined using microscopy and apoptosis assays. Bisdesmosidic saponins exhibited dose-dependent growth inhibitory and selective apoptosis-inducing activity. Growth inhibitory effects were particularly strong in a breast (MDA-MB-231) and a prostate (PC-3) cancer cell line. Total extracts exhibited a different preference being most active against a colon cancer cell line (WiDr). In a comparison of varieties, all of the total seed extracts exhibited similar dose-dependent activities, but with some variation in potency. Monodesmosidic saponins vaccarosides A and B, phenolic vaccarin, and cyclopeptide segetalin A, co-occurring seed substituents, did not exhibit activity. The non-tumorigenic fibroblast cell line BJ (CRL 2522) was growth inhibited but did not undergo apoptosis when treated with bisdesmosidic saponins at low micromolar concentrations. Saponin-rich extracts from Kochia scoparia seed and Chenopodium quinoa were also evaluated alongside Saponaria saponins but did not exhibit activity. Closely related Quillaja saponins exhibited activity but were less potent.  相似文献   

Cytotoxic, cytoprotective and antioxidant effects of isolated phenolic compounds from fresh ginger     

Peng F  Tao Q  Wu X  Dou H  Spencer S  Mang C  Xu L  Sun L  Zhao Y  Li H  Zeng S  Liu G  Hao X 《Fitoterapia》2012,83(3):568-585

Twenty-nine phenolic compounds were isolated from the root bark of fresh (Yunnan) ginger and their structures fully characterized. Selected compounds were divided into structural categories and twelve compounds subjected to in-vitro assays including DPPH radical scavenging, xanthine-oxidase inhibition, monoamine oxidase inhibition, rat-brain homogenate lipid peroxidation, and rat pheochromocytoma PC12 cell and primary liver cell viability to determine their antioxidant and cytoprotective properties. Isolated compounds were also tested against nine human tumor cell lines to characterize anticancer potency. Several diarylheptanoids and epoxidic diarylheptanoids were effective DPPH radical scavengers and moderately effective at inhibiting xanthine oxidase. An enone–dione analog of 6-shogaol (compound 2) was isolated and identified to be most effective at protecting PC12 cells from H₂O₂-induced damage. Almost all tested compounds inhibited lipid peroxidation. Three compounds, 6-shogaol, 10-gingerol and an enone-diarylheptanoid analog of curcumin (compound 6) were identified to be cytotoxic in cell lines tested, with KB and HL60 cells most susceptible to 6-shogaol and the curcumin analog with IC₅₀ < 10 μM. QSAR analysis revealed cytotoxicity was related to compound lipophilicity and chemical reactivity. In conclusion, we observed distinct compounds in fresh ginger to have biological activities relevant in diseases associated with reactive oxygen species.  相似文献   

Echinacoside promotes bone regeneration by increasing OPG/RANKL ratio in MC3T3-E1 cells     

Fei Li  Yanan Yang  Panpan Zhu  Weina Chen  Dongli Qi  Xiupu Shi  Chunfeng Zhang  Zhonglin Yang  Ping Li 《Fitoterapia》2012

Echinacoside (ECH), isolated from Cistanche tubulosa (Schrenk) R. Wight stems, was subjected to in vitro experiments to investigate its bioactivities on proliferation, differentiation and mineralization of the osteoblastic cell line MC3T3-E1. MTT assay, the alkaline phosphatase (ALP) activity and calcium deposition were determined, and the secretion of collagen I (COL I), osteocalcin (OCN), osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) were also assayed by enzyme-linked immunosorbent assay (ELISA). The results showed that ECH caused a significant increase in cell proliferation, ALP activity, COL I contents, OCN levels and an enhancement of mineralization in osteoblasts at the concentration range from 0.01 to 10 nmol·L^− 1 (p < 0.05), suggesting that ECH has a stimulatory effect on osteoblastic bone formation or has potential activity against osteoporosis. In addition, the ratio of OPG/RANKL also could be enhanced by ECH. These findings provide the potent evidence that ECH can promote bone regeneration in cultured osteoblastic MC3T3-E1 cells, which might be done by elevating the OPG/RANKL ratio, and potential evidence for echinacoside to be a promising drug or a lead compound in the development of disease-modifying drug to prevent osteoporosis.  相似文献   

中草药与苯扎溴铵联用治疗车轮虫病的案例分析     

韩阳  彭开松 《现代农业科技》2019,(17)

车轮虫病是鱼类重要的常见纤毛虫病。近年来,对传统化学药物耐药的车轮虫和小车轮虫越来越多。本文介绍了复方中草药联合苯扎溴铵治疗河鲀、黄颡鱼和草鱼车轮虫病的典型案例,以期为类似病例治疗提供参考。  相似文献   

The persistence of methyl bromide residues in rice,dried fruit,seeds and nuts following laboratory fumigation     

Kevin N T Norman 《Pest management science》2000,56(2):154-158

The persistence of methyl bromide (MB) in white rice, brown rice, sultanas, raisins, pumpkin seeds, brazil nuts, groundnuts and walnuts was monitored following laboratory fumigations at different concentration time products and temperatures. A sensitive automated headspace gas chromatographic method with a limit of quantitation of 0.005 mg kg⁻¹ was used to determine MB residues. Nuts and seeds sorbed the highest amounts of MB followed by rice and dried fruit. Measurable MB residues were shown to persist in nuts and seeds for 10 weeks and in dried fruit for four weeks following a fumigation with recommended concentration time products. The data presented suggest MB residues may persist in unprocessed nuts, seeds or dried fruit at the point of consumption using recommended fumigation practices, or particularly following overdosing or multiple fumigations. Crown copyright © 2000 Reproduced with the permission of Her Majesty's Stationery Office  相似文献   

Synthetic tetramer of a Phytophthora sojae-inducible fragment from soybean GmaSKTI36 promoter improves its pathogen induction activities     

《Physiological and Molecular Plant Pathology》2016

Using pathogen-induced promoters to control expression of the functional genes in transgenic plants may greatly increase the chances of boosting disease resistance. However, the number of the inducible promoters is limited. Here, we found that soybean GmaSKTI36 gene is strongly induced upon Phytophthora sojae infection. Functional analysis showed that its promoter could mediate rapid and strong induction of GUS expression upon pathogen infection in both Nicotiana benthamiana leaves and soybean hairy roots. Then, a 122 bp fragment that was critical to the activity was successfully identified by a progressive 5′ deletion analysis. Importantly, we found that a synthetic promoter by tetramerizing this fragment could confer strong P. sojae induction activities. Overall, the results suggested that the GmaSKTI36 promoter, the 122 bp fragment, and the synthetic promoter are potentially useful pathogen-inducible promoters.  相似文献   

金合欢基溴合成角鲨烯反应及异构体形成机理的研究   总被引：1，自引：0，他引：1  

孙震  赵振东  李冬梅  刘先章 《林产化学与工业》2005,25(2):1-5

通过自制高效偶联试剂三三苯基膦氯化亚钴和自制金合欢基溴的还原偶联反应,成功地合成了角鲨烯。初步探索了主要反应条件如反应时间等对偶联反应中产物角鲨烯得率的影响。结果表明,在常温、偶联试剂过量10％、反应4h及充分搅拌的条件下,角鲨烯得率45．6％。用GC和GC-MS分析了合成产物角鲨烯,探讨了角鲨烯6个异构体的形成机理和可能的化学结构以及在GC图谱中的出峰顺序。另外,还探讨了合成三三苯基膦氯化亚钴中硼氢化钠滴加速度和搅拌速率对反应的影响。  相似文献   

基于模糊数学法评价甲基溴及其替代技术     

刘申  张亦涛  曹坳程  张继宗  张富林  翟丽梅  王洪媛  刘宏斌 《湖北农业科学》2016,(14):3626-3630

为履行《关于消耗臭氧层物质的蒙特利尔议定书》规定,运用模糊数学综合评判法,探讨了甲基溴及其替代技术在土壤熏蒸过程中的各项因素,构建了作物产量、作物品质、病虫害防治效果、技术安全、操作过程、环境影响、应用时长和投入成本8个指标集,并划分了模糊评判集,综合评估了生姜、草莓作物甲基溴及其替代技术。生姜作物综合评估结果为甲基溴(83.61)氯化苦(79.06)棉隆(78.03)威百亩(69.07),草莓作物综合评估结果为甲基溴(69.13)氯化苦(64.60)棉隆(56.80)。各单项指标评价结果表明,甲基溴在作物产量、作物品质、防治效果以及应用时长等4个指标上均高于各项替代技术,但由于自身毒性、对臭氧层物质消耗以及受生产管控等因素的影响,在其余指标上低于替代技术;氯化苦在作物产量、作物品质和病虫害防治效果等6项指标上均高于其他替代技术,但由于为剧毒农药,而在技术安全和操作过程2项指标上低于其余替代技术。以上结果表明,生姜作物和草莓作物主流替代技术的消毒效果并不具备甲基溴的广谱性,当前最佳替代技术为氯化苦。  相似文献   

What is your diagnosis? Marked hyperchloremia in a dog     

Ida Piperisova  Jennifer A. Neel  Mark G. Papich 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(3):411-414

Abstract: A 5‐year‐old neutered male Cavalier King Charles Spaniel was evaluated for a 3‐week history of progressive paresis. The dog had been receiving potassium citrate capsules to acidify urine for the past 2 years because of an earlier history of urolithiasis. Results of neurologic examination, spinal cord radiography, and magnetic resonance imaging of the skull and spinal cord revealed no lesions that could have accounted for the neurologic signs. The main abnormalities on a clinical chemistry profile were marked hyperchloremia (179 mmol/L, reference interval 108–122 mmol/L) and an anion gap of ?50.4 mmol/L (reference interval 16.3–28.6 mmol/L). Because of the severe hyperchloremia, serum bromide concentration was measured (400 mg/dL; toxic concentration >150 mg/dL; some dogs may tolerate up to 300 mg/dL). Analysis of the potassium citrate capsules, which had been compounded at a local pharmacy, yielded a mean bromide concentration of 239 mg/capsule. Administration of the capsules was discontinued and there was rapid resolution of the dog's neurologic signs. This case of extreme bromide toxicity, which apparently resulted from inadvertent use of bromide instead of citrate at the pharmacy, illustrates the importance of knowing common interferents with analyte methodologies and of pursing logical additional diagnostic tests based on clinical and laboratory evidence, even when a patient's history appears to rule out a potential etiology.  相似文献