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Search Results: 1 - 10 of 70568 matches for " 秦巧红 "
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脂酰丙氨酸酯同系凝胶因子的合成与成胶因素的评价
叶连宝,凌浩,王晓明,
第三军医大学学报 , 2012,
Abstract: 目的合成十四、十六、十八酰丙氨酸甲酯,并对其胶凝能力进行考察。方法以丙氨酸甲酯,十四、十六、十八酰氯为原料,合成十四、十六、十八酰丙氨酸甲酯,采用IR、1H-NMR、MS确证其结构,对不同溶剂、不同温度及不同链长的胶凝能力进行研究。结果该类凝胶因子可以在大多数的有机溶剂中形成凝胶,十四、十六、十八酰丙氨酸甲酯在注射用大豆油和中链脂肪酸三甘酯(mediumchaintriglycerides,MCT)中的最低成胶浓度分别为11.9、7.2、8.5mg/ml和18.7、12.3、13.4mg/ml;3种凝胶因子在大豆油中的胶凝焓变分别为74.74、51.70kJ/mol和61.61kJ/mol。结论合成得到目标化合物具有较好的胶凝能力,可以作为局部给药的长效药物载体。
镉铅单一和复合污染对小白菜抗坏血酸含量的影响
天才,吴玉树,,
生态学杂志 , 1997,
Abstract: ?
AP-2α对滋养细胞凋亡、侵袭作用的影响

张玲,许雅娟,崔世,
- , 2017,
Abstract: ?目的?研究转录因子激活蛋白-2α(Transcription factor activator protein- 2α,AP-2α)对滋养细胞BeWo凋亡、侵袭等生物学功能的影响,探讨在子痫前期(preeclampsia, PE)发生发展中的作用。方法?将已构建的pIRES2-EGFP/AP-2α真核表达载体,采用瞬时转染的方法转入滋养细胞系BeWo细胞中,应用real time- PCR及Western blot方法,检测各组BeWo细胞中AP-2αmRNA及蛋白表达;采用流式细胞仪检测细胞凋亡,Transwell法检测转染后各组细胞侵袭力。结果?AP-2α转染BeWo细胞后AP-2αmRNA和蛋白表达量较对照组显著增加,其差异有统计学意义(P<0.05)。流式细胞仪检测细胞凋亡结果显示:与对照组比较,AP-2α转染组细胞凋亡数量明显增多,差异具有统计学意义(P<0.05);Transwell检测细胞侵袭能力实验结果显示:与对照组比较,AP-2α转染组细胞侵袭的数量显著减少,差异具有统计学意义(P<0.05)。结论?证明AP-2α促进滋养细胞凋亡并降低其侵袭力,造成滋养细胞层浅表植入,从而为子痫前期致病机理研究提供了理论依据。
英汉时间隐喻的空间化认知对比分析
A Cognitive Contrastive Analysis of Spatialization of Temporal Metaphors in English and Chinese
 [PDF]


Modern Linguistics (ML) , 2013, DOI: 10.12677/ML.2013.13021
Abstract:
由于其抽象性,时间概念在本质上是隐喻性构建的,并且时间的隐喻性思维具有跨文化的普遍性和相似性。基于Lakoff时间的流逝是运动这一总隐喻,参照NúnezMoore等学者提出的发展完善的自我参照和时间参照两大系统,本文对英汉时间隐喻空间化表征的异同进行了系统的探讨,涉及时间隐喻的源域维度,空间时间隐喻系统的共享及选择偏好,空间方向维度投射,希望能对时间概念化特别是时间隐喻的空间化表征维度达到全景式的认识。
The concept of time, being an abstract notion, is metaphorically structured in nature and such metaphorical conceptualization is shared by different cultures. Based on Lakoff’s “TIME PASSING IS MOTION” and under the developed metaphoric framework of “ego-based” and “time-based” models, the paper attempts to conduct a tentative systematic contrastive analysis of spatial-temporal metaphors in English and Chinese, with the investigation involving the classification of source domains, the elaboration on the co-occurrence of the spatial-temporal metaphorical systems, preference for a particular system and the adoption of spatial orientations. It is hoped that the paper will contribute to people’s comprehensive understanding of the conceptualization of time, and the spatial-metaphorical structuring of time in particular.
Developmental Toxicity of Perfluorooctanesulfonate with Perfluorohexanesulfonate and Perfluorobutanesulfonate to Xenopus Embryos
全氟辛烷磺酸盐(PFOS)、全氟己烷磺酸盐(PFHS)和全氟丁烷磺酸盐(PFBS)对非洲爪蟾胚胎的发育毒性

Wei Rongguo,Su Hongqiao,Qin Zhanfen,
韦荣国
,,占芬

生态毒理学报 , 2012,
Abstract: Due to wide application in various products, some of the perfluoroalkyl sulfonates (PFASs) have become ubiquitous pollutants in the environment. Considering the potential toxicity in animals and humans, perfluorooctane sulfonate (PFOS) has been banned. Short perfluorohexane sulfonate uoroalkyl chain chemicals with shorter half-life in animals and human have been introduced as substitutes, such as perfluorobutane sulfonate (PFBS). Although PFBS and perfluorohexane sulfonate (PFHS) have been widely used, their toxicity and mechanism are unclear. In this paper, a rapid, simple, and cost-effective method the frog embryo teratogenesis assay-Xenopus (FETAX), was used to evaluate the developmental toxicity and teratogenicity. The developmental toxicity of PFOS, PFHS and PFBS were evaluated based on lethal concentrations (LC50), teratogenic concentrations (EC50) and minimum concentration to inhibit growth (MCIG). LC50, EC50 and MCIG for PFOS were 51.46, 108.20 and 35 mg·L-1, respectively. LC50 of PFHS and PFBS were both higher than 100 mg·L-1, however, they did not significantly affect the morphology and growth of embryos. PFASs exposure induced the abnormal swimming behavior of embryos. The results of FETAX showed that the acute embryo toxicity of PFHS and PFBS are lower than that of PFOS.
Acute Toxicity of Perfluorooctane Sulfonate (PFOS) and Its Substitutes to Amphibian Tadpoles
全氟辛烷磺酸盐(PFOS)及替代品对两栖类蝌蚪的急性毒性

Su Hongqiao,Ren Dongkai,Cao Shan,Qin Zhanfen,
,任东凯,曹闪,占芬

生态毒理学报 , 2012,
Abstract: In this paper, the acute toxicity of perfluorooctane sulfonate (PFOS) and four substitutes on Xenopus laevis tadpoles and Rana nigromaculata tadpoles were compared. 96 h-LC50 for tri-fabric finishing agent synthetized using telomerization method (tri-fabric finishing agent) on Xenopus laevis tadpoles and Rana nigromaculata tadpoles were 8 and 21 mg·L-1, respectively, while that for PFOS on the two tadpoles were 92 and 81mg·L-1. It is indicated that acute toxicity of tri-fabric finishing agent is significantly higher than PFOS. The other three alternatives C4 and C6 tri-proof finishing agents (C4 and C6 emulsion) synthetized by electrolysis fluorination method, and 50% perfluorobutyl organic ammonium salt cationic surfactant (50% cationic surfactants) are not toxic to tadpoles at the concentration of 100 mg·L-1. Therefore, to acute toxicity, C4, C6 emulsion and 50% cationic surfactants can be used as substitutes for PFOS, however, tri-fabric finishing agent should not be a alternative of PFOS. The toxicity of PFOS and tri-fabric finishing agent on Rana nigromaculata tadpoles is different from that on Xenopus laevis tadpoles. To protect local amphibians in China, it is of practical significance that toxicity assessment will be carried out using Rana nigromaculata rather than Xenopus laevis.
Developmental Toxicity of Perfluorooctane Sulfonate (PFOS) and Its Substitutes to Amphibian Embryos
全氟辛烷磺酸盐(PFOS)及其替代品对两栖类胚胎的发育毒性

Ren Dongkai,Su Hongqiao,Liu Pengyan,Wei Rongguo,Qin Zhanfen,
任东凯
,,刘芃岩,韦荣国,占芬

生态毒理学报 , 2012,
Abstract: In this study, the developmental toxicity of perfluorooctane sulfonate (PFOS) and its four substitutes on Xenopus laevis embryos and Rana nigromaculata embryos studied comparatively. It was found that tri-fabric finishing agent synthetized using telomerization method (tri-fabric finishing agent) and 50% perfluorobutyl organic ammonium salt cationic surfactant (50% cationic surfactants) as well as PFOS had obvious toxicity to X. laevis embryos. Moreover, the toxicity of tri-fabric finishing agent and 50% cationic surfactant was significantly higher than that of PFOS. C4 and C6 tri-proof finishing agent (C4 and C6) synthetized by electrolysis fluorination method were not toxic to X. laevis embryos. To R. nigromaculata embryos, PFOS and four substitutes had no obvious toxicity. In term of biological safety, these results show that C4 and C6 might be used as the substitutes for PFOS, while tri-fabric finishing agent and 50% cationic surfactant should be considered carefully.
普适计算环境中的数字资源感知服务框架探讨

图书情报工作 , 2014,
Abstract: ?指出“以人为本,技术不可见、关注任务本身”的普适计算理念为数字图书馆资源发现服务带来全新的研究视角。以“注意力”为服务研究的认知起点,剖析普适计算环境下的数字资源服务特征,构建“感知驱动发现”的智慧型数字资源感知计算框架,为深度拓展数字图书馆知识服务提供参考思路。
2004-2013年许昌市流行性腮腺炎流行病学特征分析
Analysis of the epidemiological characteristics of mumps in Xuchang from 2004 to 2013


- , 2015,
Abstract: 摘要:目的 了解2004-2013年许昌市流行性腮腺炎流行病学特征,为制定科学防控措施提供科学依据。方法 采用描述流行病学分析方法,对疫情数据进行分析。结果 2004-2013年许昌市累计报告流行性腮腺炎4 749例,年均发病率为11.13/10万。发病以14岁及以下儿童为主,占总病例数的92.82%,其中,4~8岁儿童发病率最高;低年级学生和幼托儿童为主要发病人群,分别占总病例数的55.67%和25.25%;男性多于女性,男女性别比为2.19∶1。有明显的季节性,4-7月为发病高峰期,11月-次年1月出现次高峰。结论 采取以预防接种为主的综合性预防控制措施可减少发病。
粘弹性力学在高温铸造合金单向拉伸试验中的应用
Application of Viscoelasticity Mechanics into Uniaxial Tensile Test of High Temperature Cast Alloy
 [PDF]

, 朱大林,
International Journal of Mechanics Research (IJM) , 2013, DOI: 10.12677/IJM.2013.21002
Abstract:

给出了Kelvin链的应力–应变微分型本构关系。全面考虑初始条件,推导了Burgers四参量流体、Kelvin- Maxwell六参量模型在阶跃函数单向应力作用下的总应变通解。Burgers四参量流体、Kelvin-Maxwell六参量模型都可以近似地描述金属材料蠕变曲线的前两个阶段,但都不能反映第三个阶段。铸造Mar-M200合金蠕变曲线的计算表明,两种理论预测与实验测量的结果的一致性较好,特别是Kelvin-Maxwell六参量模型的最大相对误差仅为5.4765779%。

The stress-strain differential constitutive relation was given for Kelvin chain. On basis of all the initial conditions taken into account, the general solutions of total strain were derived for Burgers fluid with 4 parameters and Kelvin-Maxwell model with 6 ones under the step function uniaxial stress. Both Burgers fluid with 4 parameters and Kelvin-Maxwell model with 6 ones could approximately describe the former two stages of creep curve but not reflect the third stage. Numerical calculation for cast Mar-M200 alloy creep curve shows that two theories predictions are in good agreement with test measurement results, especially the maximum relative error of Kelvin-Maxwell model with 6 parameters is only 5.4765779%.

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