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Interaction of ergotamine with liver Cytochrome P450 3A in rats

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Agricultural Sciences 2012年第6期3卷 795-798页

作者： Ali S. Moubarak hehai wang Zelpha B. Johnson Charles F. Rosenkrans Department of Animal Science University of Arkansas Fayetteville AR 72701

This study was conducted to investigate the effect of the ergot alkaloid, ergotamine (ET), on the induction of CYP3A and the interaction in vivo and in vitro with ET. Sprague-Dawley rats were treated intraperitoneally for 4 days as follows: control (injecting with 0.5 ml of only corn oil);dexamethasone treatment (injecting with 100mg/kg of dexamethasone in corn oil);and ergotamine treatment (injecting with 100mg/kg of ergotamine in corn oil). Liver tissues were collected from each group (n = 5, total of 30 rats) and liver microsomes were prepared. Cytochrome CYP3A activity was evaluated using ET and its isomer as substrates in medium containing liver microsomes and NADPH at 37℃ for 30 min. HPLC was used to measure the disappearance of the substrate and the appearance of the metabolites. Liver microsomes from rats pretreated with dexamethasone were five times more (P 0.05) in activity of CYP3A when compared to the control group (5.2 vs. 7.0 nM ET/min/mg protein;SE = 4.83) or ET isomer (1.5 vs. 4.7 nM ET isomer/ min/mg protein;SE = 1.70). When ketoconazole was used as specific inhibitor of CYP3A, ergotamine metabolisms were inhibited in a dose dependent fashion reaching a maximum at an inhibitor to substrate ratio of greater than one and LD50 at 0.5 nM of ketoconazole/mg protein. The data presented in this study suggest that although the ergot alkaloids ergotamine and its isomer are ideal substrates for the isozyme CYP3A, these compounds have no effect on the induction of CYP3A after 4 days of treatment.

关键词： Microsomes Liver Rat

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乙醇激活诱导小鼠孤雌胚的发育与核型分析

畜牧与兽医 2000年第1期32卷 7-8页

作者：刘红林汪河海范必勤王公金南京农业大学动物科技学院南京210095 江苏省农科院农业生物技术实验室

注射ｈＣＧ１８～１９ｈ后收集的小鼠卵母细胞，８５％以上可为乙醇所激活，产生均质单倍体、嵌合单倍体、１个原核的杂合二倍体和２个原核的杂合二倍体４种激活类型，且它们的比率分别为８１－４％、１０－５％、４－６ ... 详细信息

注射ｈＣＧ１８～１９ｈ后收集的小鼠卵母细胞，８５％以上可为乙醇所激活，产生均质单倍体、嵌合单倍体、１个原核的杂合二倍体和２个原核的杂合二倍体４种激活类型，且它们的比率分别为８１－４％、１０－５％、４－６％和３－５％。单倍体胚胎体外培养后有少数可发育至囊胚期。单倍体孤雌胚在８细胞期开始出现二倍体核型，从而形成单倍体胚胎、单倍体二倍体嵌合胚和二倍体胚胎。孤雌胚的核型中还出现较高比率的非整倍体。

关键词：小鼠卵母细胞孤雌激活孤雌胚核型乙醇激活

兔精子微注射受精研究 Ⅳ精子机械损伤对受精和发育的影响

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农业生物技术学报 1998年第4期 85-88页

作者：汪河海钟声刘红林范必勤丁家桐江苏农科院牧医所扬州大学农学院动物科学系南京农业大学动物科技学院

冷冻或超声波处理兔精子会导致精子一定程度的损伤，这种损伤的性质多属机械性的，表现在精子活力的降低与结构完整性的破坏；兔精子微注射受精试验表明，上述两种类型的精子损伤并不影响微注射卵正常受精反应的发生与受精卵早期发育的... 详细信息

冷冻或超声波处理兔精子会导致精子一定程度的损伤，这种损伤的性质多属机械性的，表现在精子活力的降低与结构完整性的破坏；兔精子微注射受精试验表明，上述两种类型的精子损伤并不影响微注射卵正常受精反应的发生与受精卵早期发育的正常卵裂行为，说明微注射受精中精子的活力及其结构的完整性不是卵子受精和发育所必需；但超声波处理对微注射卵的受精率和发育率却有明显的不良影响，提示超声波处理后脱落的胞质成分中可能含有某种与受精有关的活性因子。

关键词：兔精子微注射受精反应机械损伤活力与结构完整性

显微注射Ca^(2+)激活小鼠MⅡ期卵母细胞

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畜牧兽医学报 1997年第3期28卷 206-210页

作者：刘红林汪河海范必勤陈宜峰江苏省农业科学院

胞质内显微注入Ｃａ２＋可以激活小鼠ＭⅡ期卵母细胞，且随着卵龄的增加，激活率明显升高。卵龄小于１６ｈ（ｈＣＧ注射后）注射Ｃａ２＋引起的激活率很低，卵龄超过１８ｈ，激活率达到５０％以上。卵龄小于１６ｈ的卵母细胞，卵内注入... 详细信息

胞质内显微注入Ｃａ２＋可以激活小鼠ＭⅡ期卵母细胞，且随着卵龄的增加，激活率明显升高。卵龄小于１６ｈ（ｈＣＧ注射后）注射Ｃａ２＋引起的激活率很低，卵龄超过１８ｈ，激活率达到５０％以上。卵龄小于１６ｈ的卵母细胞，卵内注入超纯水未能激活卵母细胞，而在１８～１９ｈ卵龄组，注射水的对照组激活率为３５％，但显著或极显著地低于注射Ｃａ２＋的试验组。激活前注射ＥＤＴＡ卵母细胞的激活率约为３０％，激活后注射ＥＤＴＡ卵母细胞的激活率高达５０％以上，二种处理激活率出现显著差异。胞质内注入肝素，无论有无外源Ｃａ２＋。

关键词：小鼠卵母细胞乙醇激活显微注射繁殖

Principle, Method of Object-Relation Hypermedia Data Model and Its Application in the Multimedia Spatial Data Management

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Journal of Systems Engineering and Electronics 2000年第1期11卷 53-60页

作者： wang, Jianhua Guo, Jingjun Zhu, Guorui Wu, hehai Tsinghua Univ Beijing China

In this paper, a new multimedia data model, namely object-relation hypermedia data model (O-RHDM) which is an advanced and effective multimedia data model is proposed and designed based on the extension and integration of non first normal form (NF2) multimedia data model. Its principle, mathematical description, algebra operation, organization method and store model are also discussed. And its specific application example, in the multimedia spatial data management is given combining with the Hainan multimedia touring information system.

关键词： Data structures Information management Mathematical models

Mathematical Foundation of Visual Query Languageon Spatial Information

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Journal of Systems Engineering and Electronics 2000年第4期11卷 66-72页

作者： wang Jianhua Guo Jingjun Yan Huiwu Zhu Guorui Wu hehai Department of Civil Engineering Tsinghua UniversityBeijing 100084 P. R. China Department of Civil Engineering Tsinghua UniversityBeijing 100084 P. R. China

Visual Query Language on Spatial Information (SIVQL) is one kind of visual query language based on the extension of Query by Example (QBE). It is a visual operation based on graphics or media object, such as point, line and area elements. In this paper, the relation calculation and query function of SIVQL have been studied and discussed by using set theory and relation algebra. The theory foundation of SIVQL has been investigated by the mathematical method. Finally, its application examples are also given with the specific information system.

关键词： Visual query language Relation algebra Mathematical foundation

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聚氨酯离聚体微畴体积的研究

物理学报 1988年第9期 1522-1526页

作者：尹传元蒋澄华王化勤南京大学物理系河海大学南京大学现代分析中心

本文用聚氨酯离聚体材料作X射线小角度散射实验,同时还作了正电子湮没及比重法测量材料密度的辅助实验,以研究聚氨酯离聚体微畴体积随金属离子价改变。实验结果表明,随着金属离子价数的增加,反离子半径增大,微畴的体积增大,致使材料的... 详细信息

本文用聚氨酯离聚体材料作X射线小角度散射实验,同时还作了正电子湮没及比重法测量材料密度的辅助实验,以研究聚氨酯离聚体微畴体积随金属离子价改变。实验结果表明,随着金属离子价数的增加,反离子半径增大,微畴的体积增大,致使材料的密度增大,自由体积相应减小。

关键词：聚氨酯离聚体小角度散射正电子湮没

Melatonin alleviates intervertebral disc degeneration by disrupting the IL-1β/NF-κB-NLRP3 inflammasome positive feedback loop

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Bone Research 2020年第2期8卷 169-181页

作者： Fan Chen Guowei Jiang Hui Liu Zemin Li Yuxin Pei Hua wang hehai Pan Haowen Cui Jun Long Jianru wang Zhaomin Zheng Department of Spine Surgery The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510080China Department of Pediatric Intensive Care Unit The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510080China Pain Research Center Sun Yat-Sen UniversityGuangzhou 510080China

The inflammatory response is induced by the overexpression of inflammatory cytokines, mainly interleukin(IL)-1β, and is one of the main causes of intervertebral disc degeneration(IVDD). NLR pyrin domain containing 3(NLRP3) inflammasome activation is an important source of IL-1β. As an anti-inflammatory neuroendocrine hormone, melatonin plays various roles in different pathophysiological conditions. However, its roles in IVDD are still not well understood and require more examination. First, we demonstrated that melatonin delayed the progression of IVDD and relieved IVDD-related low back pain in a rat needle puncture IVDD model;moreover, NLRP3 inflammasome activation(NLRP3, p20, and IL-1β levels) was significantly upregulated in severely degenerated human discs and a rat IVDD model. Subsequently, an IL-1β/NF-κB-NLRP3 inflammasome activation positive feedback loop was found in nucleus pulposus(NP) cells that were treated with IL-1β. In these cells, expression of NLRP3 and p20 was significantly increased, NF-κB signaling was involved in this regulation, and mitochondrial reactive oxygen species(mt ROS)production increased. Furthermore, we found that melatonin disrupted the IL-1β/NF-κB-NLRP3 inflammasome activation positive feedback loop in vitro and in vivo. Melatonin treatment decreased NLRP3, p20, and IL-1β levels by inhibiting NF-κB signaling and downregulating mt ROS production. Finally, we showed that melatonin mediated the disruption of the positive feedback loop of IL-1β in vivo. In this study, we showed for the first time that IL-1β promotes its own expression by upregulating NLRP3 inflammasome activation. Furthermore, melatonin disrupts the IL-1β positive feedback loop and may be a potential therapeutic agent for IVDD.

关键词： NLRP3 degeneration inflam

PROGRESSIVE GRAPHIC SIMPLIFICATION OF CONTOURS BASED ON SPATIAL REASONING

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Geo-spatial Information Science 2000年第4期3卷 67-72页

作者： GUO Qingsheng wang Tao MAO Jianhua WU hehai [FK(W12。32ZQ] School of Land Science Wuhan China

This paper discusses the rules representing relief with contour lines and methods for automatically constructing relation of contour ***,the improvement of existent methods for extracting the topographic characteristic points and lines is *** the basis of this analysis,we propose a series of practicable progressive graphic simplification ideas of contour lines and concrete algorithms for the exception’s *** this way,graphic generalizations of contour lines at different scales are integrated into one model that is convenient to implement,and in which contour lines’ intersection in generalization can be controlled.

关键词： contour line graphic simplification topographic terrain feature progressive cartographic generalization