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Development of a Rapid and Simultaneous Detection Method for Buprenorphine, Norbuprenorphine and Naloxone in Human Plasma Using Ultra-high Performance Liquid Chromatography- tandem Mass Spectrometer with Solid-phase Extraction

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Chinese Journal of Chemistry 2011年第9期29卷 1922-1926页

作者： guo, Qiaozhen du, Zhenxia Faculty of Science Beijing University of Chemical Technology Beijing 100029 China

A simultaneous method was successfully established and validated for the separation and determination of bu- prenorphine （BP）, its primary metabolite, nor-buprenorphine （NBP） and a proposed co-formulate, naloxone （NLX） in human plasma. The method used buprenorphine-d4 （BP-D4）, nor-buprenorphine-d3 （NBP-D3）, naltrexone （NTX） as internal standards （ISs）. 100 μL of plasma sample fortified with the ISs was cleaned up by solid-phase extraction （SPE）, and was then separated on a Waters AcquityTM BEH C18 column with gradient elution using methanol and water （containing 0.2% formic） at a flow rate of 0.25 mL·min^-1. The mass spectrometer was used for detection and was operated in the positive electrospray ionization with multiple reaction monitoring （MRM） mode. The three compounds were effectively separated in 5 min. The linear ranges of the compounds were 0.1--25, 0.25--25 and 0.05--25 ng·mL^-1 for BP, NBP and NLX, respectively, with r≥0.9935. The method had high sensitivity （the lim- its of detection were 0.02, 0.1 and 0.01 ***-1 for BP, NBP and NLX, respectively） and high recoveries （≥97.6%）. The result was shown to be linear and satisfactorily met current acceptance criteria for validation of bio- analytical method： intra and inter assay precisions within the required limits of ≤25% RSD. The LOQs fulfilled the LOQ requirements： precision≤25% RSD, and was fully validated according to the State Food and Drug Administration （SFDA） regulations. The results demonstrated that ultra-high performance liquid chromatography- tandem mass spectrometer （UPLC-MS/MS） with SPE was a powerful detection tool and contributed to pharmaceutical analysis in biological matrices.

关键词： ultra-high performance liquid chromatography-tandem mass spectrometer buprenorphine naloxone,norbuprenorphine human plasma

Current patterns of plant diversity and phylogenetic structure on the Kunlun Mountains

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Plant Diversity 2022年第1期44卷 30-38页

作者： Wei-Bo du Peng Jia guo-Zhen du State Key Laboratory of Grassland and Agro-Ecosystems School of Life SciencesLanzhou UniversityLanzhouGansu Province730000P.R.China

Large-scale patterns of biodiversity and the underlying mechanisms that regulate these patterns are central topics in biogeography and *** Qinghai-Tibet Plateau serves as a natural laboratory for studying these ***,most previous studies have focused on the entire Qinghai-Tibet Plateau,leaving independent physical geographic subunits in the region less well *** studied the current plant diversity of the Kunlun Mountains,an independent physical geographic subunit located in northwestern China on the northern edge of the Qinghai-Tibet *** integrated measures of species distribution,geological history,and phylogeography,and analyzed the taxonomic richness,phylogenetic diversity,and community phylogenetic structure of the current plant diversity in the *** distribution patterns of 1911 seed plants showed that species were distributed mainly in the eastern regions of the Kunlun *** taxonomic richness,phylogenetic diversity,and genera richness showed that the eastern regions of the Kunlun Mountains should be the priority area of biodiversity conservation,particularly the southeastern *** proportion of Chinese endemic species inhabiting the Kunlun Mountains and their floristic similarity may indicate that the current patterns of species diversity were favored via species *** Hengduan Mountains,a biodiversity hotspot,is likely the largest source of species colonization of the Kunlun Mountains after the *** net relatedness index indicated that 20 of the 28 communities examined were phylo-genetically dispersed,while the remaining communities were phylogenetically *** nearest taxon index indicated that 27 of the 28 communities were phylogenetically *** results suggest that species colonization and habitat filtering may have contributed to the current plant diversity of the Kunlun Mountains via ecological and evolutionary processes,and habitat filtering may play an impor

关键词： Biodiversity Plant community Kunlun mountains Phylogenetic structure Seed plants

基于压电传感器的纤维陶粒混凝土冻融损伤检测

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科学技术与工程 2024年第2期24卷 576-583页

作者：江子航翟荃张继承杜国锋长江大学城市建设学院荆州434023 中建三局第一建设工程有限责任公司武汉430040

针对纤维陶粒混凝土低温下受到冻融损伤导致影响结构安全性问题,基于压电陶瓷传感器进行损伤检测。利用压电传感技术对冻融后的纤维陶粒混凝土试件进行检测,获得不同冻融次数下的应力波信号。当冻融次数增加,试件相对动弹模量和抗弯强... 详细信息

针对纤维陶粒混凝土低温下受到冻融损伤导致影响结构安全性问题,基于压电陶瓷传感器进行损伤检测。利用压电传感技术对冻融后的纤维陶粒混凝土试件进行检测,获得不同冻融次数下的应力波信号。当冻融次数增加,试件相对动弹模量和抗弯强度下降,压电陶瓷检测到的应力波信号幅值相应减小,基于应力波的衰减,采用小波包能量分析法将其转化为损伤指数,与冻融试验评价指标损伤程度和抗弯强度损失率进行拟合,吻合度较高。结果表明,纤维陶粒混凝土损伤指数与冻融损伤程度和抗弯强度损失率相关性较强,该纤维陶粒混凝土冻融损伤无损检测方法具有良好可行性。

关键词：纤维陶粒混凝土抗弯强度冻融损伤损伤检测压电陶瓷小波包能量分析

海啸作用下滨水挡土墙抗震滑动稳定性上限分析

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中国科技论文 2024年第3期19卷 305-312页

作者：刘杰郭督马志宏河北工程大学土木工程学院河北邯郸056000

针对沿海地区滨水挡土墙在海啸和地震联合作用下易发生被动破坏的问题,结合极限分析上限法和拟静力法确定地震荷载,研究了海啸作用下滨水挡土墙的抗震滑动稳定性。通过建立墙体滑动与破坏区土楔体整体滑动的墙-土系统及速度容许场,推导... 详细信息

针对沿海地区滨水挡土墙在海啸和地震联合作用下易发生被动破坏的问题,结合极限分析上限法和拟静力法确定地震荷载,研究了海啸作用下滨水挡土墙的抗震滑动稳定性。通过建立墙体滑动与破坏区土楔体整体滑动的墙-土系统及速度容许场,推导出水平地震加速度系数(kh)的表达式。分析了海啸、海平面与地下水高度及墙-地和墙-土摩擦角对地震屈服加速度系数的影响。结果表明,控制地下水位在适当高度并增大墙-土摩擦角可以有效提高滨水挡土墙的抗震滑动稳定性。与经典极限平衡理论相比,该方法考虑了土体的塑性流动及挡土墙的位移模式,且无需计算地震被动土压力的值。

关键词：滨水挡土墙极限分析上限法滑动稳定性水平地震加速度系数海啸

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大孔树脂吸附法纯化酸枣仁总黄酮的工艺研究

中国调味品 2024年第1期49卷 100-106页

作者：杜国军洪婉婷李占锋刘禹萱齐齐哈尔大学食品与生物工程学院黑龙江齐齐哈尔161006

利用7种大孔树脂对酸枣仁的总黄酮进行纯化,依据其吸附能力及解吸能力,选出最佳的大孔树脂型号,研究了上样液浓度、上样速度、上样液体积对大孔树脂吸附率的影响以及洗脱剂类型、洗脱剂浓度、洗脱速度、洗脱剂体积对大孔树脂解吸率的影... 详细信息

利用7种大孔树脂对酸枣仁的总黄酮进行纯化,依据其吸附能力及解吸能力,选出最佳的大孔树脂型号,研究了上样液浓度、上样速度、上样液体积对大孔树脂吸附率的影响以及洗脱剂类型、洗脱剂浓度、洗脱速度、洗脱剂体积对大孔树脂解吸率的影响,采用正交试验对酸枣仁总黄酮的纯化工艺进行了优化。试验结果表明,DM301大孔树脂纯化酸枣仁总黄酮效果最佳,在上样液浓度为0.1 mg/mL、上样速度为1 BV/h、上样液体积为30 mL、洗脱剂为丙酮、洗脱剂浓度为100%、洗脱速度为2 BV/h、洗脱剂体积为55 mL的条件下,获得的酸枣仁总黄酮纯度最高,相较于纯化前提高了约1.1倍。

关键词：酸枣仁总黄酮大孔树脂正交试验纯化

Potential Mechanisms Involved in Ceramide-induced Apoptosis in Human Colon Cancer HT29 Cells

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Biomedical and Environmental Sciences 2009年第1期22卷 76-85页

作者： JING WANG XIAO-WEN LV AND Yu-guo du State Key Laboratory of Envtronmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Feed Research Institute Chinese Academy of Agricultural Sciences Beijing 100081 China

Objective To investigate the potential mechanisms of cell death after the treatment with ceramide. Methods MTT assay, DNA ladder, reporter assay, FACS and Western blot assay were employed to investigate the potential mechanisms of cell death after the treatment with C2-ceramide. Results A short-time treatment with C2-ceramide induced cell death, which was associated with p38 MAP kinase activation, but had no links with typical caspase activation or PARP degradation. Rather than caspase inhibitor, Inhibitor of p38 MAP kinase blocked cell death induced by a short-time treatment with ceramide （〈12 h）. However, inhibition of p38 MAP kinase could not block cell death induced by a prolonged treatment with ceramide （〉12 h）. Moreover, incubation of cells with ceramide for a long time （〉12 h） increased subG1, but reduced S phase accompanied by caspase-dependent and caspase-independent changes including NFr, B activation. Conclusion Ceramide-induced cell apoptosis involves both caspase-dependent and -independent signaling pathway. Caspase-independent cell death occurring in a relatively early stage, which is mediated via p38 MAP kinase, can progress into a stage involving both caspase-dependent and -independent mechanisms accompanied by cell signaling of MAPKs and NFκB.

关键词： Ceramide HT29 cells Apoptosis Cell signaling p38 MAPK NFκB

基于最优权重和形状文法的关中民间艺术在家具设计上的应用

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林产工业 2024年第8期61卷 70-75页

作者：詹秦川杜国龙赵洋王显周清华陕西科技大学设计与艺术学院陕西西安710000 江西理工大学江西赣州341000

为了对陕西关中地区民间艺术进行归纳和梳理,本文构建了陕西关中地区民间艺术文化基因图谱,并运用现代设计方法进行转译,赋予了关中地区民间艺术活态化、多样化、年轻化的呈现。首先,通过对陕西关中地区的实地考察和相关文献资料的整理... 详细信息

为了对陕西关中地区民间艺术进行归纳和梳理,本文构建了陕西关中地区民间艺术文化基因图谱,并运用现代设计方法进行转译,赋予了关中地区民间艺术活态化、多样化、年轻化的呈现。首先,通过对陕西关中地区的实地考察和相关文献资料的整理分析,深入解读和探究关中地区的民间艺术。然后,引入“文化基因”理论,从形态、色彩、材质、语义、环境、纹样六个方面剖析陕西关中民间艺术的文化因子,并结合文化创意表现,拓宽陕西关中民间艺术的表现形式和传播手段。最后,通过对文化因子的时尚化转化,并结合多元设计形式,实现了对传统关中地区民间艺术内涵的继承和创新,为陕西民间艺术装饰内涵和形态创新的传承和发展提供了新理念、新思路、新方法。

关键词：最优权重关中文化民间艺术家具设计文化因子形状文法

Effect of preoperative transcatheter arterial chemoembolization on angiogenesis of hepatocellular carcinoma cells

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World Journal of Gastroenterology 2009年第36期15卷 4582-4586页

作者： En-Hua Xiao Dong guo du-lun Bian Department of Radiology the Second Xiangya Hospital Central SouthUniversity Changsha 410011 Htman Province China

AIM： To evaluate the effects of four types of preoperative transcatheter arterial chemoembolization （TACE） on angiogenesis of hepatocellular carcinoma （HCC） ceils. METHODS： A total of 136 patients with HCC underwent liver resection. One to five courses of TACE prior to liver resection were performed in 79 patients （TACE group）, in which one to four courses of chemotherapy alone were performed in 11 patients （group A）; one to five courses of chemotherapy combined with iodized oil were performed in 33 patients （group B）; one to three courses of chemotherapy combined with iodized oil and gelatin sponge were performed in 23 patients （group C）, one to three courses of chemotherapy combined with iodized oil, ethanol and gelatin sponge were performed in 12 patients （group D）. The other 57 patients only received liver resection （non-TACE group）. The microvessels were marked by CD31. The expression of CD31 and vascular endothelial growth factor （VEGF） protein were detected by immunohistochemical methods. RESULTS： The mean microvessel density （MVD） in HCC cells was significantly higher in groups A, B, C and D than in the nonACE group （P 〈 0.05）. The expression of VEGF protein in HCC cells were significantly higher in groups A, B, C and D than in the non-TACE group （P 〈 0.05）. MVD and the expression of VEGF protein were positively correlated. Mean MVD and the expression of VEGF protein were closely related to the number of courses of TACE and the interval of TACE. CONCLUSION： Four different types of preoperative TACE regimens enhanced angiogenesis in HCC cells by up-regulating the expression of VEGF protein. It is necessary to repress angiogenesis of liver cancer after TACE.

关键词： Angiogenesis Hepatocellular carcinoma Immunohistochemistry Transcatheter arterial chemoembolization Vascular endothelial growth factor

Effects of Chinese herbs combined with in vitro fertilization and embryo transplantation on infertility:a clinical randomized controlled trial

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Journal of Traditional Chinese Medicine 2014年第3期34卷 267-273页

作者： Jia guo Dong Li Cheng Liu Xiao lanJi Rong Li Xiao guo du Department of Traditional Chinese Medicine the Third Hospital Affiliated to Beijing University Reproductive Center the Third Hospital Affiliated to Beijing University

OBJECTIVE： To assess the effects of using Chinese herbs in assisted reproductive technology. METHODS： Four hundred and thirty-three subjects aged less than 42 years with infertility due to Fallo- pian tube or male-related factors who were willing to undertake in vitro fertilization and embryo trans- plantation were randomly allocated to a Chinese herb intervention group （n=216） or a conventional treatment control group （n=217）. All subjects re- ceived one of four routine ultra-ovulation-promot- ing therapies at the Reproductive Center in the Third Hospital Affiliated to Beijing University ac- cording to their physician＇s assessments. The sub- jects in the intervention group received various Chi- nese herbs depending on their conventional treat- ment. Endometrial thickness, number of acquired eggs, and rates of normal fertility, high-quality em- bryos, biochemical and clinical pregnancy of sub- jects were assessed in both ***： The high-quality embryo rate of 51.9%, biochemical pregnancy rate of 51.0%, clinical preg- nancy rate of 44.2% and endometrial thickness of （10.84± 1.75） mm in the intervention group were all significantly higher than those in the control group [48.7%, 38.9%, 34.8%, and （10.52±1.50） mm, respec- tively; P〈O.05]. The normal fertility rate of 58.5% in the Chinese herb group was also significantly supe- rior to the 54.7% achieved in the control group （P〈 0.01）. There were no statistically significant differ- ences （P〉0.05） in the average number of acquired eggs within a single cycle, incidence of excessive stimulation of ovary, rates of embryo transplanta- tion or early abortion and birth of living babies be- tween the two groups. CONCLUSION： Our findings indicate that Chinese herbs increase endometrial thickness, improve the quality of fertility and embryo, and promote embry- onic nidation, thus enhancing the success rate of in vitro fertilization/intracytoplasmic sperm injec- tion-embryo transplantation cycle. Using Chinese herbs impro

关键词： Embryo transfer Fertilization in vitro In-fertility, female Pregnancy rate Drugs, Chineseherbal Randomized controlled trial