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A new ent-labdane diterpenoid from Andrographis paniculata

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Chinese Chemical Letters 2010年第9期21卷 1091-1093页

作者： Qiong Yu Zou Na Li Chun Dan Wen Long Deng shu lin Peng Li Sheng Ding Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041 China College of Materials and Chemistry & Chemical Engineering Chengdu University of Technology Chengdu 610059 China Sichuan Key Laboratory of Quality and Innovation Research of Chinese Materia Medica Sichuan Academy of Chinese Medicine Scieiwes Chengdu 610041 China

A new ent-labdane diterpenoid,19-O-β-D-glucopyranosyl-ent-labda-8（17）,13-dien-15,16,19-triol,together with six known ent-labdane diterpenoids,was isolated from the aerial parts of Andrographis *** structure of the ... 详细信息

关键词： Andrvgraphis paniculata Acanthaceae ent-Labdane diterpenoid

Production of Transgenic Mice by Type-A Spermatogonia-Mediated Gene Transfer

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Agricultural Sciences in China 2011年第3期10卷 431-437页

作者： JU Hui-ming BAI Li-jing REN Hong-yan MU Yu-lian YANG shu-lin LI Kui Key Laboratory for Farm Animal Genetic Resources and Utilization Ministry of Agriculture~Institute of Animal Science Chinese Academyof Agricultural Sciences Beijing 100193 P.R. China College of Veterinary Medicine Yangzhou University Yangzhou 225009 P.R. China

Type-A spermatogonia first appear at between 3-7 d postnatally in mice and are the only immortalized diploid cells that reproduce in adulthood in these animals. In our current study, we explored the feasibility of producing stable transgenic mice using these cells. Enhanced pEGFP-N1 plasmids were suspended in ExGen500 transfection reagent and injected at different angles into the testes of 7-d-old male ICR mice. The resulting type-A spermatogonia-mediated gene transfer （TASMGT） mice were then mated with normal females at different stages of sexual maturity （6, 12, and 24 wk）. The integration and expression of the introduced EGFP gene was evaluated in the F1 transgenic offspring by PCR and Southern blotting analysis. The foreign gene integration rates for a low-dose group （15 μL gene suspension injected into each testis） and a high-dose group （30 μL suspensions injected） at the three stages of female sexual maturity tested were 11.76% （2/17）, 14.29% （3/21）, and 11.11% （2/18）, and 5% （1/20）, 5.56% （1/18）, and 0 （0/17）, respectively. The average integration rates for these two dose groups were 12.5% （7/56） and 3.64% （2/55）, respectively, which was a significant difference （P0.05）. Semi-quantitative RT-PCR analysis further showed that the introduced GFP gene was expressed in 3/9 integration mice. In addition, GFP expression was observed in the sperm cells from the TASMGT mice, and also in the embryos and F2 pups from the F1 generation transgenic mice. Hence, although the foreign gene integration rate for TASMGT is not high and the transgenic offspring show as yet unexplained defects, our results indicate that this method is a potentially feasible and reproducible new approach to creating transgenic mice.

关键词： type-A spermatogonia transgenic mice enhanced green fluorescent protein type-A spermatogonia-mediated gene transfer

Gossypol detoxification in the rumen and Helicoverpa armigera larvae:A review

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Animal Nutrition 2021年第4期7卷 967-972页

作者： Wei-Kang Wang Hong-Jian Yang Yan-Lu Wang Kai-Lun Yang lin-shu Jiang Sheng-Li Li State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing100193China Beijing Engineering Technology Research Center of Raw Milk Quality and Safety Control College of Animal Science and TechnologyChina Agricultural UniversityBeijing100193China College of Animal Sciences Xinjiang Agricultural UniversityUrumuqi830052China College of Animal Science and Technology Beijing University of AgricultureBeijing102206China

Gossypol,a phenolic compound found in the cotton plant,is widely distributed in cottonseed *** ruminant animals are believed to be more tolerant of gossypol toxicity than monogastric animals due to rumen microbial fermentation,the actual mechanisms of detoxification remain *** contrast,the metabolic detoxification of gossypol by Helicoverpa armigera(Lepidoptera:Noctuidae)larvae has achieved great *** present review discusses the clinical signs of go ssypol in ruminant animals,as well as summarizing advances in the study of gossypol detoxification in the *** also examines the regulatory roles of several key enzymes in gossypol detoxification and transformation known in *** the rapid development of modern molecular biotechnology and-omics technology strategies,evidence increasingly indicates that research into the biological degradation of gossypol in *** larvae and some microbes,in terms of these key enzymes,could provide scientific insights that would underpin future work on microbial gossypol detoxification in the rumen,with the ultimate aim of further alleviating gossypol toxicity in ruminant animals.

关键词： Detoxification Gossypol Helicoverpa armigera Rumen

Stability analysis of open-pit gold mine slopes and optimization of mining scheme in Inner Mongolia,China

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Journal of Mountain Science 2020年第12期17卷 2997-3011页

作者： REN shu-lin TAO Zhi-gang HE Man-chao PANG Shi-hui LI Meng-nan XU Hao-tian State Key Laboratory for Geomechanics&Deep Underground Engineering Beijing 100083China School of Mechanics and Civil Engineering China University of Mining&TechnologyBeijing 100083China

The geological structure of the Changshanhao open-pit mine in Urad Middle Banner,Inner Mongolia,China is extremely complicated,and slope instability has frequently occurred in various forms,such as wedge sliding,bedding sliding,and toppling *** order to study the failure mechanisms of these slopes,the geological structure and mechanical rock properties were investigated based on field investigations and laboratory *** models for the present mining area and final mining area of the original scheme were established to analyze slope *** results showed that the unique geomorphological characteristics of the mining area were generated by geological tectonism,and the north side of the stope is an anti-dip layered rock slope and the south side is a dip layered rock *** failure is the consequence of endogenic and exogenic integration,including physical and mechanical properties of the rock mass,geological structures such as faults and joints,and human-caused factors such as blasting and excavation *** the original excavation scheme was redesigned mainly by optimizing the slope angle and decreasing the final mining depth to maintain slope ***,the Monte Carlo method was used to analyze the reliability of the slope angle optimization *** open-pit mine excavation plan that meets the stability requirements was obtained eventually.

关键词： Open pit mine Slope stability Numerical simulation Excavation scheme

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斜向激振模式下振动轮滞回耦合特性分析

振动与冲击 2015年第22期34卷 47-53页

作者：郑书河林述温福建农林大学机电工程学院福州350002 福州大学机械工程及自动化学院福州350108

据斜向激振模式下振动压实土壤的水平、垂直两方向滞回恢复力与位移间所呈不同滞回形态,考虑土壤密实度较高时振动轮在土壤面层水平方向发生的脱耦打滑、垂直方向发生脱耦跳振现象,采用仅据土壤特性参数的水平对称、垂直不对称滞回模型... 详细信息

据斜向激振模式下振动压实土壤的水平、垂直两方向滞回恢复力与位移间所呈不同滞回形态,考虑土壤密实度较高时振动轮在土壤面层水平方向发生的脱耦打滑、垂直方向发生脱耦跳振现象,采用仅据土壤特性参数的水平对称、垂直不对称滞回模型,分阶段按工况建立系统动力学方程;在一次近似前提下,利用谐波线性法将非线性作用力线性化为等效刚度及等效阻尼。通过数值计算,研究斜向激振下振动轮水平、垂直方向非线性滞回响应及相互耦合特性,分析压实进程中振动轮发生连耦、滑转及跳振工况下响应特性及工况相互转换规律。结果表明,压实进程中合理调整激振参量,一定程度可避免振动轮发生跳振、打滑现象,从而保证压实质量、效率及驾驶舒适性。

关键词：智能振动压路机斜向激振模式滞回模型滑转跳振耦合特性

考虑打滑现象的振动压路机振动轮的滞回响应特性研究

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振动与冲击 2014年第18期33卷 72-76,83页

作者：郑书河林述温福建农林大学机电工程学院福州350002 福州大学机械工程及自动化学院福州350108

水平振动压实下土壤的滞回恢复力与位移呈现对称滞回特性,考虑土壤的密实度较高时振动轮在土壤面层发生脱耦打滑现象,采用双线性对称滞回模型建立分段的二自由度振动压路机动力学方程,在一次近似前提下,利用谐波线性法将非线性作用力线... 详细信息

水平振动压实下土壤的滞回恢复力与位移呈现对称滞回特性,考虑土壤的密实度较高时振动轮在土壤面层发生脱耦打滑现象,采用双线性对称滞回模型建立分段的二自由度振动压路机动力学方程,在一次近似前提下,利用谐波线性法将非线性作用力线性化为等效刚度和等效阻尼。通过数值仿真研究振动轮在水平激振下非线性滞回响应特性。结果表明:在对称滞回力的作用下,振动轮发生超谐波共振,频谱呈现以基波为主,仅含明显的高奇次倍谐波特性。随土壤密实度的增大,振动轮频谱呈现明显的偶次倍和分数倍谐波成分,标志打滑的发生,一定条件下振动轮进入复杂的拟周期运动。合理调整激振参量,可在一定程度下抑制打滑,使得振动轮维持稳定的倍周期运动。

关键词：水平激振土壤参数对称滞回模型打滑拟周期运动

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爆振加固法中的水力劈裂及作用范围研究

岩土工程学报 2018年第S2期40卷 53-57页

作者：林澍闫澍旺贾沼霖天津大学水利工程仿真与安全国家重点实验室天津大学建筑工程学院华电重工股份有限公司博士后科研工作站

爆振加固法是一种高效、经济的地基加固方式,其炸药量的选择和药包布置间距的确定对爆振加固的作用效果起决定作用。由于现有的爆振加固计算方法较为繁琐,根据经典爆炸理论、Mohr-Coulomb准则和土体强度参数,从水力劈裂角度提出更便于... 详细信息

爆振加固法是一种高效、经济的地基加固方式,其炸药量的选择和药包布置间距的确定对爆振加固的作用效果起决定作用。由于现有的爆振加固计算方法较为繁琐,根据经典爆炸理论、Mohr-Coulomb准则和土体强度参数,从水力劈裂角度提出更便于工程应用的爆振作用范围确定方法,研究了炸药量和土体参数对爆振作用范围的影响,并与试验结果进行了对比,两者对应较好。研究结果表明,在炸药量一定的情况下,药包埋置深度h越大,则土体围压作用越大,爆振作用范围越小;土体强度参数c、φ越大,则土体强度越高,爆振作用范围越小。最后,对爆振加固方法在使用过程中的药量选择及药包布置间距的确定给出了一定的工程建议。

关键词：地基加固爆振水力劈裂作用范围

A magic eggshell:Cu^(2+) reacts with S^(2-) to produce metal Cu,rather than CuS

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Chinese Science Bulletin 2010年第18期55卷 1851-1853页

作者： ZHANG WenLi WANG Zhao SHAO Bing NI Liang QIU lin QIU shu School of Chemistry and Chemical Engineering Jiangsu University Zhenjiang 212013 China

In common sense,the chemical reaction between Cu2+ and S2-ions produces black precipitation of ***,if they are separated by an eggshell,they produce copper with trace amount of CuS on the surface of the eggshell at the side of copper chloride solution within one *** an unexpected phenomenon strongly indicated that Cu2+ is able to be reduced into metal copper when S2-diffuses throughout the porous *** produced copper was verified by reacting with nitric acid to generate red-brown nitrogen dioxide at ambient temperature,as well as by the powder X-ray diffraction(XRD) and energy dispersive analysis of X-rays(EDS).

关键词：化学反应金属铜 CuS 蛋壳生产粉末X射线衍射二氧化氮色散分析

Rutaecarpine Inhibits Intimal Hyperplasia in A Balloon-Injured Rat Artery Model

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Chinese Journal of Integrative Medicine 2018年第6期24卷 429-435页

作者： XU Yang CHEN Xiu-ping ZHANG Feng HOU Hua-hua ZHANG Jing-yi lin shu-xian SUN An-sheng Key Laboratory of Basic Pharmacology of Guizhou and Department of Pharmacology Zunyi Medical College Molecular Oncology Laboratory Eastern Hepatobiliary Surgery HospitalSecond Military Medical University Institute of Chinese Medical Sciences University of Macao

Objective： To investigate the effect and potential mechanisms of rutaecarpine （Rut） in a rat artery balloon-injury model. Methods： The intimal hyperplasia model was established by rubbing the endothelia with a balloon catheter in the common carotid artery （CCA） of rats. Fifty rats were randomly divided into five groups, ie. sham, model, Rut （25, 50 and 75 mg/kg） with 10 rats of each group. The rats were treated with or without Rut （25, 50, 75 mg/kg） by intragastric administration for 14 consecutive days following injury. The morphological changes of the intima were evaluated by hematoxylin-eosin staining. The expressions of proliferating cell nuclear antigen （PCNA） and smooth muscle （SM） oL-actin in the ateries were assayed by immunohistochemical staining. The mRNA expressions of c-myc, extracellular signal-regulated kinase 2 （ERK2）, MAPK phosphatase-1 （MKP-1） and endothelial nitric oxide synthase （eNOS） were determined by real-time reverse chain reaction. The protein expressions of MKP-1 and phosphorylated ERK2 （p-ERK2） were examined by Western blotting. The plasma contents of nitric oxide （NO） and cyclic guanosine 3＇,5＇-monophosphate （cGMP） were also determined. Results： Compared with the model group, Rut treatment significantly decreased intimal thickening and ameliorated endothelial injury （P〈0.05 or P〈0.01）. The positive expression rate of PCNA was decreased, while the expression rate of SM α -actin obviously increased in the vascular wall after Rut （50 and 75 mg/kg） administration （P〈0.05 or P〈0.01）. Furthermore, the mRNA expressions of c-myc, ERK2 and PCNA were downregulated while the expressions of eNOS and MKP-1 were upregulated （P〈0.05 or P〈0.01）. The protein expressions of MKP-1 and the phosphorylation of ERK2 were upregulated and downragulated after Rut （50 and 75 mg/kg） administration （P〈0.05 or P〈0.01）, respectively. In addition, Rut dramatically reversed balloon injury-induced decrease of NO and cGMP in the plasma （P〈0.05 or P〈0.01）. Conclusion： Rut c

关键词： rutaecarpine balloon-injury intimal hyperplasia extracellular signal-regulated kinase 2 nitric oxide