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Analysis of the binding sites with NL-101 to amino acids and peptides by HPLC/MS/MS
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作者 Lingzi Dai Nian Guo +3 位作者 Yaqin Liu Shanshan Shen Qiufu Ge Yuanjiang Pan 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第1期103-106,共4页
The binding between NL-101, a novel nitrogen mustard anti-cancer drug, with amino acids and peptides has been investigated by high performance liquid chromatography electrospray tandem mass spectrometry(HPLC/ESI-MS/MS... The binding between NL-101, a novel nitrogen mustard anti-cancer drug, with amino acids and peptides has been investigated by high performance liquid chromatography electrospray tandem mass spectrometry(HPLC/ESI-MS/MS). This study offers supporting data of the interaction among drug and amino acids and peptides, which could potentially explain the cytotoxic and mutagenic effects of the drug. Collision-induced dissociation(CID) experiment demonstrated that under the same collision energy, the amino group combined with NL-101 adducts are sensitive and often produce more fragment ions;the carboxyl group combined with NL-101 adducts are hard to break and display fewer fragment ions. In addition, when other group(like sulfhydryl group) of amino acids binds to NL-101, CID spectra show different fragmentation pattern. These differences could display structural information about the drug adducts and be utilized as location of the authentic binding sites. 展开更多
关键词 HIGH-PERFORMANCE liquid chromatography/ TANDEM mass spectrometry NL-101 AMINO ACIDS PEPTIDES Binding sites
基于液相色谱-质谱联用技术探索胃癌的糖肽生物分子标志物 预览
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作者 杨楠 范国荣 《药学服务与研究》 CAS 2019年第1期19-24,共6页
目的:探索胃癌病人血清中潜在的N-糖肽生物分子标志物。方法:采用超高效液相色谱串联三重四级杆质谱法(UPLC-QqQ-MS/MS)对胃癌病人和胃炎病人血清中的N-糖肽进行定量分析,通过独立样本t检验与偏最小二乘法(partialleastsquares,PLS)对... 目的:探索胃癌病人血清中潜在的N-糖肽生物分子标志物。方法:采用超高效液相色谱串联三重四级杆质谱法(UPLC-QqQ-MS/MS)对胃癌病人和胃炎病人血清中的N-糖肽进行定量分析,通过独立样本t检验与偏最小二乘法(partialleastsquares,PLS)对数据进行分析。结果:对约60种N-糖肽进行统计分析,找到7个具有显著性差异的N-糖肽,分别为N4400-IgG1、N5400-IgG1、N4410-IgG1、N3500-IgA、N5400-IgA、N5402-IgA和N5501-J。以这7种N-糖肽对测试组进行PLS分析,结果表明胃炎病人和胃癌病人之间已出现一定的分离趋势。结论:本研究发现了胃癌潜在的N-糖肽生物分子标志物。该方法为探索胃癌生物分子标志物提供了有力的技术支持,对胃癌的早期诊断具有重要临床意义。 展开更多
关键词 胃癌 N-糖肽 生物分子标志物 色谱法 高效液相 质谱法 联用
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南五味子低极性化学成分的GC-MS分析 预览
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作者 王瀚萱 郑巍 +3 位作者 董家潇 陈海生 郭良君 金永生 《药学服务与研究》 CAS 2019年第1期25-28,51共5页
目的:研究南五味子中主要的低极性化学成分。方法:用95%乙醇热提取南五味子,提取液用石油醚(沸程60~90℃)萃取得到石油醚部位。采用GC-MS法检测其主要成分,将测定结果与标准谱库对比分析,用峰面积归一法计算各个成分的相对含量。结果:... 目的:研究南五味子中主要的低极性化学成分。方法:用95%乙醇热提取南五味子,提取液用石油醚(沸程60~90℃)萃取得到石油醚部位。采用GC-MS法检测其主要成分,将测定结果与标准谱库对比分析,用峰面积归一法计算各个成分的相对含量。结果:从南五味子石油醚提取部位鉴定出47种化学成分,主要以倍半萜类化合物为主(占82.35%),脂肪酸及其酯类化合物次之(占5.8%)。其中含量最高的两个化合物为喇叭烯氧化物(Ⅱ)(22.71%)和别香橙烯氧化物(Ⅱ)(11.98%)。13种化学成分为首次从该属植物中发现。结论:与水蒸气蒸馏法、超临界CO2提取法、索式提取法相比,采用乙醇提取后石油醚萃取的方法获得的南五味子主要成分基本相同,但含量不同,且本研究提取的成分中脂肪酸和酯类化合物含量较低。 展开更多
关键词 南五味子 低极性化学成分 倍半萜类 色谱法 气相 质谱法 联用
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Parallel transjugular intrahepatic portosystemic shunt with Viatorr? stents for primary TIPS insufficiency: Case series and review of literature
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作者 Driss Raissi Qian Yu +1 位作者 Michael Nisiewicz Steven Krohmer 《世界肝病学杂志:英文版(电子版)》 2019年第2期217-225,共9页
BACKGROUND Transjugular intrahepatic portosystemic shunts (TIPS) can alleviate complications of portal hypertension such as ascites and variceal bleeding by decreasing the portosystemic gradient. In limited clinical s... BACKGROUND Transjugular intrahepatic portosystemic shunts (TIPS) can alleviate complications of portal hypertension such as ascites and variceal bleeding by decreasing the portosystemic gradient. In limited clinical situations, parallel TIPS may be only solution to alleviate either variceal bleeding or ascites secondary to portal hypertension when the primary TIPS fails to do so. Data specifically addressing the use of this partially polytetrafluoroethylene covered nitinol stent (Viatorr■) is largely lacking despite Viatorr■ being the current gold standard for modern TIPS placement. CASE SUMMARY All three patients had portal hypertension and already had a primary Viatorr■ TIPS placed previously. All patients have undergone failed endoscopy to manage acute variceal bleeding before referral for a parallel stent (PS). PS were placed in patients presenting with recurrent variceal bleeding despite existence of a widely patent primary TIPS. Primary stent patency was verified with either Doppler ultrasound or intra-procedural TIPS stent venography. Doppler ultrasound follow-up imaging demonstrated complete patency of both primary and parallel TIPS. All three patients did well on clinical follow-up of up to six months and no major complications were recorded. A review of existing literature on the role of PS in the management of portal hypertension complications is discussed. There are three case reports of use of primary and PS Viatorr? stents placement, only one of which is in a patient with gastrointestinal variceal bleeding despite a patent primary Viatorr? TIPS. CONCLUSION Viatorr?PS placement in the management of variceal hemorrhage is feasible with promising short term patency and clinical follow-up data. 展开更多
关键词 Transjugular INTRAHEPATIC portosystemic SHUNT PARALLEL stent Portal hypertension VARICES Viatorr? Tandem Double BARREL Case report
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Determination of 24 Allergens in Perfume with High Performance Liquid Chromatography Tandem Mass Spectrometry
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作者 Wang Yujian Liang Zhengang +1 位作者 Fu Lingmei Dong Cunzhu 《日用化学品科学(英文版)》 2019年第1期40-46,共7页
A method of 24 allergens determination in cosmetics were established with high performance liquid chromatography tandem mass spectrometry. The targeted compounds were extracted with acetonitrile and determined with LC... A method of 24 allergens determination in cosmetics were established with high performance liquid chromatography tandem mass spectrometry. The targeted compounds were extracted with acetonitrile and determined with LC-MS/MS (MRM mode) with external method. The linearity between concentrations and peak area ratio was obtained from 1.0~5.0 mg/L. The limits of detection were 1.0 mg/L for the instrument and 5.0 mg/kg for the method respectively. The LOQ was 15.0 mg/L. The average recoveries of 24 allergens were between 85.9% and 110.0% at spiked levels of 5, 10 and 20 mg/kg with relative standard derivation (RSDs) of 5.5%~12.0%(n=10). The method could be used as a reliable means for simultaneous quantitative determination of allergens in cosmetics. 展开更多
关键词 PERFUME allergens FLAVOR high performance liquid CHROMATOGRAPHY TANDEM mass SPECTROMETRY
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An Automatic Solid Phase Extraction and Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry for Determination of Seven Microcystins at Ultra-Trace Levels in Surface Water
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作者 SHEN Fei XU Yanjuan +1 位作者 WANG Ye CHEN Jing 《武汉大学学报:自然科学英文版》 CAS CSCD 2019年第1期30-36,共7页
A method was developed for the detection of seven microcystins(microcystin-LR,RR,YR,LA,LY,LW and LF)in surface water using automatic solid-phase extraction(A-SPE)coupled with ultra-performance liquid chromatography ta... A method was developed for the detection of seven microcystins(microcystin-LR,RR,YR,LA,LY,LW and LF)in surface water using automatic solid-phase extraction(A-SPE)coupled with ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS).The automated solid-phase extraction system was used to extract microcystins(MCs)from water samples.UPLC-MS/MS was used to determine MCs concentrations in just 5 min.Method detection limits were from 0.3 to 0.9 ng/L,microcystin recoveries ranged from 83.8%to 114%,and the relative standard deviation(RSD)varied from 5.6%to 12.5%.This analytical approach was found to be simple,highly sensitive,accurate,which required little manual operation.Additionally,to validate this analytical method,A-SPE+UPLC-MS/MS was applied to characterize the concentration of MCs in Taihu Lake,Wuxi,China. 展开更多
关键词 MICROCYSTINS AUTOMATIC SOLID-PHASE extraction ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS)
矿井液压支架高强度结构钢焊接工艺试验研究
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作者 杨萍 《煤炭技术》 2018年第4期248-250,共3页
首先设计了矿井液压支架高强度结构钢焊接工艺试验,给出TANDEM双丝焊和GMAW双丝焊技术的对比试验,对接焊缝、力学效能和焊接能量对比,进而采用ANSYS模拟高强度结构钢温度场和变形预测.实验结果表明TANDEM双丝焊比GMAW双丝焊技术力... 首先设计了矿井液压支架高强度结构钢焊接工艺试验,给出TANDEM双丝焊和GMAW双丝焊技术的对比试验,对接焊缝、力学效能和焊接能量对比,进而采用ANSYS模拟高强度结构钢温度场和变形预测.实验结果表明TANDEM双丝焊比GMAW双丝焊技术力学效能好,能推进熔化速率与热敷率.结构变形量小。 展开更多
关键词 液压支架 焊接 TANDEM GMAW 温度场
用LC/MS法测定雷公藤甲素纳米乳中雷公藤甲素的含量 预览
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作者 范兆峰 归小龙 黄赛杰 《药学服务与研究》 CAS 2018年第6期444-447,共4页
目的:建立LC/MS法测定雷公藤甲素(triptolide,TPL)纳米乳中TPL的含量.方法:采用ZORBAX Extend-C18柱(100mm×2.1mm,3.5μm),流动相为0.1%(V/V)甲酸水溶液∶甲醇(40∶60),流速0.3ml/min,柱温40℃,进样量30μl.采用电喷雾离子化(ESI)... 目的:建立LC/MS法测定雷公藤甲素(triptolide,TPL)纳米乳中TPL的含量.方法:采用ZORBAX Extend-C18柱(100mm×2.1mm,3.5μm),流动相为0.1%(V/V)甲酸水溶液∶甲醇(40∶60),流速0.3ml/min,柱温40℃,进样量30μl.采用电喷雾离子化(ESI)正离子检测,多反应监测(MRM)扫描方式,考察准分子离子、碎片离子、干燥气流速、雾化压力、裂解电压以及碰撞能量对TPL测定方法的影响.确定质谱条件后考察TPL含量测定方法学.结果:质谱条件确定定量分析离子m/z=361.3/105.2,干燥气流速8L/min,干燥气温度350℃,毛细管电压4000V,雾化器压力275.79kPa(40psi),裂解器电压105eV,碰撞能量33.含量测定方法专属性良好,TPL的浓度在10~500ng/ml范围内线性关系良好(r=0.9999).供试品在处理后8h内基本稳定,日内、日间精密度RSD<5.55%,平均加样回收率为(99.90±1.32)%(n=3).TPL纳米乳中TPL的含量为(242.9±2.10)μg/g(n=3).结论:本研究建立的LC/MS检测方法准确、灵敏,重现性良好,可用于TPL纳米乳中药物含量的检测. 展开更多
关键词 雷公藤甲素 纳米乳 含量测定 色谱法 液相 质谱法 联用
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A liquid chromatography with tandem mass spectrometry method for quantitating total and unbound ceritinib in patient plasma and brain tumor 预览
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作者 Xun Bao Jianmei Wu +1 位作者 Nader Sanai Jing Li 《药物分析学报:英文版》 CAS CSCD 2018年第1期20-26,共7页
A rapid,sensitive,and robust reversed-phase liquid chromatography with tandem mass spectrometry method was developed and validated for the determination of total and unbound ceritinib,a secondgeneration ALK inhibitor,... A rapid,sensitive,and robust reversed-phase liquid chromatography with tandem mass spectrometry method was developed and validated for the determination of total and unbound ceritinib,a secondgeneration ALK inhibitor,in patient plasma and brain tumor tissue samples.Sample preparation involved simple protein precipitation with acetonitrile.Chromatographic separation was achieved on a Waters ACQUITY UPLC BEH C18column using a4-min gradient elution consisting of mobile phase A(0.1%formic acid inwater)andmobile phase B(0.1%formic acid in acetonitrile),at a flow rate of0.4mL/min.Ceritinib and the internal standard([13C6]ceritinib)were monitored using multiple reaction monitoring mode under positive electrospray ionization.The lower limit of quantitation(LLOQ)was1nM of ceritinib in plasma.The calibration curve was linear over ceritinib concentration range of1-2000nM in plasma.The intra-and interday precision and accuracy were within the generally accepted criteria for bioanalytical method(<15%).The method was successfully applied to assess ceritinib brain tumor penetration,as assessed by the unbound drug brain concentration to unbound drug plasma concentration ratio,in patients with brain tumors. 展开更多
关键词 Ceritinib REVERSED-PHASE liquid chromatography with tandem mass spectrometry (LC–MS/MS) FRACTION unbound in PLASMA FRACTION unbound in BRAIN tissue BRAIN tumor penetration Unbound brain-to-plasma PARTITION coefficient
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串列竖轴水轮机尾流场影响CFD模拟分析
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作者 孙科 李岩 +1 位作者 王凯 张亮 《哈尔滨工业大学学报》 CSCD 北大核心 2018年第5期185-191,共7页
为研究串列水轮机组水动力性能并提出合理的水轮机布置方案,提高潮流能电站的发电效率,针对三叶片竖轴水轮机进行瞬态数值模拟,分析了串列布置水轮机组上游水轮机的水动力性能及尾流场对下游水轮机水动力性能的影响.考虑到竖轴水轮机叶... 为研究串列水轮机组水动力性能并提出合理的水轮机布置方案,提高潮流能电站的发电效率,针对三叶片竖轴水轮机进行瞬态数值模拟,分析了串列布置水轮机组上游水轮机的水动力性能及尾流场对下游水轮机水动力性能的影响.考虑到竖轴水轮机叶片展向剖面相同的特点,将模型简化为二维模型并利用开源流体力学软件Open FOAM对水轮机进行了数值分析.首先通过模拟单个水轮机的运行,得出了能量利用率随叶尖速比的变化规律,并通过与文献中实验数据的对比验证了Open FOAM数值模型在合理的设置下,采用k-ωSST湍流模型和PIMPLE算法,可以准确计算二维竖轴水轮机的水动力性能.之后模拟了两个串列放置的水轮机,水轮机之间的距离范围取5~50倍水轮机直径,分析得出了竖轴水轮机后方各剖面的尾流特性,以及水轮机间距对下游水轮机水动力性能的影响特性.分析结果表明,两个串列水轮机的间距大于40倍水轮机直径时,上游水轮机尾流场对下游水轮机性能的影响可以忽略. 展开更多
关键词 竖轴水轮机 串列 尾流 数值模拟 水动力性能
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BanSatDB,a whole-genome-based database of putative and experimentally validated microsatellite markers of three Musa species
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作者 Vasu Arora Neera Kapoor +4 位作者 Samar Fatma Sarika Jaiswal Mir Asif Iquebal Anil Rai Dinesh Kumar 《作物学报:英文版》 CAS CSCD 2018年第6期642-650,共9页
The genus Musa is one of three genera in the family Musaceae,which includes bananas and plantains,which are monocotyledonous plants.Bananas have valuable nutritional content of vitamin C,B6,minerals,and dietary fiber ... The genus Musa is one of three genera in the family Musaceae,which includes bananas and plantains,which are monocotyledonous plants.Bananas have valuable nutritional content of vitamin C,B6,minerals,and dietary fiber and are a rich food energy source,given that carbohydrates account for 22%–32%of fruit weight.Molecular markers are valuable for crop improvement and population genetics studies.The availability of whole-genome sequence and in silico approaches has revolutionized bulk marker discovery.We describe an online web genomic resource,BanSatDB(http://webtom.cabgrid.res.in/bansatdb/)having the highest number(>341,000)of putative STR markers from Musa genera so far,represented by three species:M.acuminata(110,000),M.balbisiana(107,000),and M.itinerans(124,000)from 11 chromosomes of each species.BanSatDB has also been populated with 580 validated STR markers from the published literature.It is based on a three-tier architecture using MySQL,PHP and Apache.The markers can be retrieved by use of multiple search parameters including chromosome number(s),microsatellite types(simple or compound),repeat nucleotides(1–6),copy number,microsatellite length,pattern of repeat motif,and chromosome location.These markers can be used for Distinctness,Uniformity and Stability(DUS)tests of variety identification and for marker assisted selection(MAS)in variety improvement and management.These STRs have also proved to be helpful in classification of Musa germplasm to distinguish individual accessions and in the development of a standardized procedure for genotyping.These markers can also be used in gene discovery and QTL mapping.The database represents a source of markers for developing and implementing new approaches for molecular breeding,which are required to enhance banana productivity. 展开更多
关键词 MUSACEAE MUSA BANANA MICROSATELLITE Short tandem repeat(STR) PRIMERS
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分隔板、控制杆及减振器对串联立管涡激振动抑制的试验分析 预览
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作者 娄敏 路顺 王琮 《船海工程》 北大核心 2018年第4期138-142,共5页
针对分隔板、控制杆和减振器3种抑振装置对串联立管涡激振动的抑制效果问题,在波流水槽中进行不同间距下串联立管的裸管试验以及抑振管涡激振动试验。试验结果表明,在同一流速条件下,附加抑振装置后立管的振动振幅与裸管相比明显降低,... 针对分隔板、控制杆和减振器3种抑振装置对串联立管涡激振动的抑制效果问题,在波流水槽中进行不同间距下串联立管的裸管试验以及抑振管涡激振动试验。试验结果表明,在同一流速条件下,附加抑振装置后立管的振动振幅与裸管相比明显降低,所采用的3种抑振装置可不同程度抑制海洋立管的涡激振动。对于横向振动最优抑制效果来说,控制杆的最优抑制效果最好;对于顺流向振动最优抑制效果来说,分隔板在上游立管中的最优抑制效果最好,控制杆在下游立管中的最优抑制效果最佳。综合比较各间距与振动方向的最优抑制效果,控制杆能够对串联立管横向与顺流向的振动起到不错的抑制效果。 展开更多
关键词 涡激振动 分隔板 控制杆 减振器 串联
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人血浆中阿戈美拉汀的浓度测定及其药动学研究 预览
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作者 程捷 贺娟 +3 位作者 茅晓寅 周沁逸 张梦琪 张慧 《药学服务与研究》 CAS 2018年第3期199-202,共4页
目的:建立LC-MS/MS法测定阿戈美拉汀在人血浆中的浓度,并测定其在健康志愿者体内的药动学参数。方法:以ACQUITY UPLC BEH C18柱(50mm×2.1mm,1.7μm)为分析柱,50mmol/L甲酸铵-甲酸-水(0.75∶1.25∶98)溶液(A)-乙腈(B)为... 目的:建立LC-MS/MS法测定阿戈美拉汀在人血浆中的浓度,并测定其在健康志愿者体内的药动学参数。方法:以ACQUITY UPLC BEH C18柱(50mm×2.1mm,1.7μm)为分析柱,50mmol/L甲酸铵-甲酸-水(0.75∶1.25∶98)溶液(A)-乙腈(B)为流动相,梯度洗脱(0~0.65min,43%B相;0.65~0.66min,43%~90%B相;0.66~1.00min,90%B相;1.00~1.10min,90%~43%B相,1.10~2.50min,43%B相)。采用电喷雾离子源,多离子反应监测(MRM)正离子扫描分析。阿戈美拉汀和内标阿戈美拉汀-氘6离子对分别为m/z244.1→185.1和m/z250.1→188.1。测定48名健康志愿者单剂量口服阿戈美拉汀25mg后的血药浓度和药动学参数。结果:在0.05~10.00ng/ml浓度范围内,阿戈美拉汀具有良好的线性关系。日内、日间精密度RSD均〈6%,平均提取回收率在77.28%~83.67%(n=6)。单次口服给药后,阿戈美拉汀的cmax为(16.16±31.52)ng/ml,AUC0~∞为(17.05±21.17)ng·h·ml~(-1),AUC0~12h为(16.95±21.11)ng·h·ml~(-1),tmax为(1.20±0.88)h,t1/2为(0.96±0.33)h。结论:本方法简便、灵敏、精确,重现性好,可用于人血浆中阿戈美拉汀浓度的测定及药动学研究。 展开更多
关键词 阿戈美拉汀 血药浓度 药代动力学 色谱法 高效液相 质谱法 联用
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A Resource for Inactivation of MicroRNAs Using Short Tandem Target Mimic Technology in Model and Crop Plants
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作者 Ting Peng Mengmeng Qiao +26 位作者 Haiping Liu Sachin Teotia Zhanhui Zhang Yafan Zhao Bobo Wang Dongjie Zhao Lina Shi Cui Zhang Brandon Le Kestrel Rogers Chathura Gunasekara Haitang Duan Yiyou Gu Lei Tian Jinfu Nie Jian Qi Fanrong Meng Lan Huang Qinghui Chen Zhenlin Wang Jinshan Tang Xiaoqing Tang Ting Lan Xuemei Chen Hairong Wei Quanzhi Zhao Guiliang Tang 《分子植物:英文版》 SCIE CAS CSCD 2018年第11期1400-1417,共18页
microRNAs (miRNAs)are endogenous small non-coding RNAs that bind to mRNAs and target them for cleavage and/or translational repression,leading to gene silencing.We previously developed short tandem target mimic (STTM)... microRNAs (miRNAs)are endogenous small non-coding RNAs that bind to mRNAs and target them for cleavage and/or translational repression,leading to gene silencing.We previously developed short tandem target mimic (STTM)technology to deactivate endogenous miRNAs in Arabidopsis.Here,we created hundreds of STTMs that target both conserved and species-specific miRNAs in Arabidopsis,tomato,rice,and maize,providing a resource for the functional interrogation of miRNAs.We not only revealed the functions of several miRNAs in plant development,but also demonstrated that tissue-specific inactivation of a few miRNAs in rice leads to an increase in grain size without adversely affecting overall plant growth and development.RNA-seq and small RNAseq analyses of STTM156/157 and STTM165/166 transgenic plants revealed the roles of these miRNAs in plant hormone biosynthesis and activation,secondary metabolism,and ion-channel activity-associated electrophysiology,demonstrating that STTM technology is an effective approach for studying miRNA functions.To facilitate the study and application of STTM transgenic plants and to provide a useful platform for storing and sharing of information about miRNA-regulated gene networks,we have established an online Genome Browser (https://blossom.ffr.mtu.edu/designindex2.php) to display the transcriptomic and miRNAomic changes in STTMinduced miRNA knockdown plants. 展开更多
关键词 SHORT TANDEM TARGET MIMIC (STTM) miRNA RNA-seq Arabidopsis CROP
Resistance to FLT3 inhibitors in acute myeloid leukemia:Molecular mechanisms and resensitizing strategies
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作者 Jianbiao Zhou Wee-Joo Chng 《世界临床肿瘤学杂志》 2018年第5期90-97,共8页
FMS-like tyrosine kinase 3(FLT3)is classified as a typeⅢreceptor tyrosine kinase,which exerts a key role in regulation of normal hematopoiesis.FLT3 mutation is the most common genetic mutation in acute myeloid leukem... FMS-like tyrosine kinase 3(FLT3)is classified as a typeⅢreceptor tyrosine kinase,which exerts a key role in regulation of normal hematopoiesis.FLT3 mutation is the most common genetic mutation in acute myeloid leukemia(AML)and represents an attractive therapeutic target.Targeted therapy with FLT3 inhibitors in AML shows modest promising results in current ongoing clinical trials suggesting the complexity of FLT3 targeting in therapeutics.Importantly,resistance to FLT3 inhibitors may explain the lack of overwhelming response and could obstruct the successful treatment for AML.Here,we summarize the molecular mechanisms of primary resistance and acquired resistance to FLT3 inhibitors and discuss the strategies to circumvent the emergency of drug resistance and to develop novel treatment intervention. 展开更多
关键词 FMS-like TYROSINE KINASE 3 TYROSINE KINASE domain Internal tandem DUPLICATION FLT3 inhibitor Drug RESISTANCE Acute MYELOID leukemia Combination therapy
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Novel caped Pd nanoparticles-liquid chromatography-tandem mass spectrometry for the identification of oxygenates in Saudi Arabian crude oil 预览
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作者 Nagy E.MOUSTAFA Kout El-Kloub Fars MAHMOUD 《色谱》 CSCD 北大核心 2018年第4期362-369,共8页
Saudi Arabian crude oil is a super complex mixture and,up to now,there has been little research into its heteroatom-containing compounds.First,oxygenated compounds(OCs)were isolated from Saudi Arabian oil using a Pd n... Saudi Arabian crude oil is a super complex mixture and,up to now,there has been little research into its heteroatom-containing compounds.First,oxygenated compounds(OCs)were isolated from Saudi Arabian oil using a Pd nanoparticle exchange complex,which formed between the nano-Pds and the oxygenated ligands.Normally,polycyclic aromatic sulphur heterocycles(S-PAHs)are separated from petroleum oil via the same method.The obtained results reveal that all the OC formulations with S-PAHs can be separated from the pre-isolated aromatic fraction of crude oil via this approach.S-PAHs are mixtures of benzothiophene and dibenzothiophene congeners.The isolated OCs are composed mainly of hydroxyl compounds.The liquid chromatography(LC)/electrospray ionization(ESI)in positive ion mode ESI(+)/tandem mass spectrometry(MS/MS)technique was used to assign the molecular weight distribution and identify the isolated OCs.The LC/ESI(+)-MS/MS technique differentiates S-PAHs and OCs using protonated ions.Thus,LC/ESI(+)-MS/MS can be used to assign molecular weight distributions for both the groups as a single mixture.MS/MS in precursor ion mode was used for the immediate identification of the target S or O analytes. 展开更多
关键词 liquid chromatography(LC) TANDEM mass spectrometry(MS/MS) Pd nanoparticles CRUDE oil OXYGENATES
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The pattern of plasma BCAA concentration and liver Bckdha gene expression in GK rats during T2D progression
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作者 Wenlu Zhang Yu'e Wu +3 位作者 Wei Fan Hongmei Chen Hongli Du Junhua Rao 《动物模型与实验医学(英文)》 2018年第4期305-313,共9页
Background:This study was conducted to measure the concentration of branched chain amino acid(BCAA)in different species and detect the expression pattern of the liver Bckdha gene in Goto‐Kakizaki(GK)rats during type ... Background:This study was conducted to measure the concentration of branched chain amino acid(BCAA)in different species and detect the expression pattern of the liver Bckdha gene in Goto‐Kakizaki(GK)rats during type 2 diabetes(T2D)progression.Methods:We measured the concentration of BCAA in GK rats,induced T2D cynomolgus monkeys and T2D humans by liquid chromatography tandem mass spectrometry,and used real‐time quantitative PCR to analyze the gene expression of Bckdha and Bckdk,which encode the rate‐limiting enzymes in catabolism of,respectively,branched chain amino acids and branched chainα‐keto acid dehydrogenase kinase.Results:In this study,we showed that GK rat BCAA concentrations were significantly reduced at 4 and 8 weeks(P<0.05 and P<0.01,respectively),while the expression of Bckdha in GK rat liver was increased at 4 and 8 weeks(1.62‐fold and 1.93‐fold,respectively).The BCAA concentrations were significantly reduced in dietinduced T2D cynomolgus monkeys(P<0.01),but significantly increased in T2D humans(P<0.001).Conclusions:Our results showed that BCAA concentrations changed at different times and by different amounts in different species and during different periods of T2D progress,and the significant changes of BCAA concentration in the three species indicated that BCAA might participate in the progress of T2D.The results suggested that the increased expression of Bckdha in GK rat liver might partially explain the reduced plasma BCAA concentration at 4 and 8 weeks.Further studies are required to investigate the exact mechanism of BCAA changes in non‐obese T2D. 展开更多
关键词 GK rat liquid chromatography TANDEM mass spectrometry LIVER NON-OBESE
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Synthesis of Benzofuran-fused 1,4-Dihydropyridines via Bifunctional Squaramide-catalyzed Formal [4+2] Cycloaddition of Azadienes with Malononitrile
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作者 Zheng GU BO Wu +1 位作者 Guo-Fang Jiang Yong-Gui Zhou 《中国化学:英文版》 SCIE CAS CSCD 2018年第12期1130-1134,共5页
An efficient bifunctional squaramide-catalyzed Michael addition/cyclization of azadienes with malononitrile has been successfully developed,providing a facile access to chiral benzofuran-fused 1,4-dihydropyridines wit... An efficient bifunctional squaramide-catalyzed Michael addition/cyclization of azadienes with malononitrile has been successfully developed,providing a facile access to chiral benzofuran-fused 1,4-dihydropyridines with excellent yields,wide substrate scope and up to 99% ee.Additionally, this formal [4+2]cycloaddition can be performed in gram scale without noticeable loss of yield and enantioselectivity. 展开更多
关键词 1 4-dihydropyridines CYCLOADDITION AZADIENES tandem reactions ORGANOCATALYSIS asymmetric synthesis
thanatin串联抗菌肽原核表达研究 预览
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作者 刘伟 李清海 刘仁虎 《浙江农业学报》 CSCD 北大核心 2018年第5期804-809,共6页
抗菌肽thanatin是一类广谱性的阳离子抗菌活性肽,对病原性真菌有很好的杀灭效果。为了提高thanatin抗菌肽表达丰度,将3个thanatin单体拷贝基因进行串联,与MBP蛋白进行融合表达,表达的产物经过酶切纯化后,通过Western blot和质谱鉴定,结... 抗菌肽thanatin是一类广谱性的阳离子抗菌活性肽,对病原性真菌有很好的杀灭效果。为了提高thanatin抗菌肽表达丰度,将3个thanatin单体拷贝基因进行串联,与MBP蛋白进行融合表达,表达的产物经过酶切纯化后,通过Western blot和质谱鉴定,结果表明3×thanatin在大肠埃希菌中成功表达,对核盘菌的抑菌活性测定结果表明,原核表达的3×thanatin最低抑菌浓度为6.6μmol·L-1,而化学合成的thanatin抗菌肽对核盘菌的抑菌浓度约为64μmol·L-1,3×thanatin抗菌肽对核盘菌的抑菌活性提升了约1个数量级。 展开更多
关键词 抗菌肽 THANATIN 串联 表达
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Photovoltaic Cells and Modules towards Terawatt Era
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作者 Vitezslav Benda 《电子科技学刊:英文版》 CAS CSCD 2017年第4期351-357,共7页
Progresses in photovoltaic technologies over the past years are evident from the lower costs, the rising efficiency, to the great improvements in system reliability and yield. Cumulative installed power yearly growths... Progresses in photovoltaic technologies over the past years are evident from the lower costs, the rising efficiency, to the great improvements in system reliability and yield. Cumulative installed power yearly growths were on an average more than 40% in the period from 2007 to 2016 and in 2016, the global cumulative photovoltaic power installed has reached 320 GWp. The level 0.5 TWp could be reached before 2020. The production processes in the solar industry still have great potential for optimization both wafer based and thin film technologies. Trends following from the present technology levels are discussed, also taking into account other parts of photovoltaic systems that influence the cost of electrical energy produced. Present developments in the three generations of photovoltaic modules are discussed along with the criteria for the selection of appropriate photovoltaic module manufacturing technologies. The wafer based crystalline silicon (csilicon)technologies have the role of workhorse of present photovoltaic power generation, representing more than 90% of total module production. Further technology improvements have to be implemented without significantly increasing costs per unit, despite the necessarily more complex manufacturing processes involved. The tandem of c-silicon and thin film cells is very promising. Durability may be a limiting factor of this technology due to the dependence of the produced electricity cost on the module service time. 展开更多
关键词 Crystalline SILICON (c-silicon) CELLS PHOTOVOLTAIC CELLS PHOTOVOLTAIC (PV) tandem CELLS thin film MODULES
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