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应用知识生产与基础知识生产的特征性差异——基于中国省际的面板数据分析 被引量:3
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作者 许娇 叶阿忠 《软科学》 CSSCI 北大核心 2010年第10期1-5,共5页
运用Eviews6.0软件,基于2003~2007年中国29个省市的面板数据,对应用知识生产与基础知识生产进行实证分析,结果表明两者存在特征性差异。应用知识生产具有较高的产出弹性,基础知识生产的产出弹性则较低;各省市应用知识的生产能力与经济... 运用Eviews6.0软件,基于2003~2007年中国29个省市的面板数据,对应用知识生产与基础知识生产进行实证分析,结果表明两者存在特征性差异。应用知识生产具有较高的产出弹性,基础知识生产的产出弹性则较低;各省市应用知识的生产能力与经济发展水平没有必然的联系,而基础知识的生产能力与经济发展水平具有一定的相关性。政府要针对应用知识生产与基础知识生产的特征,分别采取适当的措施,建设和形成基础知识生产与应用知识生产相互促进的强大的自主创新体系,推动中国经济的可持续发展。 展开更多
关键词 基础知识生产 应用知识生产 特征性差异
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内源性细胞因子对鼻咽癌细胞体外移动效果及其特征性差异蛋白质组的改变
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作者 赵宋礼 潘斌才 +1 位作者 付汐 卢国英 《海峡药学》 2016年第5期215-217,共3页
目的分析转化生长因子α(Transforing growth factorα,TGF-α)对人体鼻咽癌细胞株CNE2特征性差异蛋白质组的影响,研究并探讨表皮生长因子受体(EGFR)在人鼻咽癌中的作用信号途径。方法将人鼻咽癌CNE2细胞分为两组,以TGF-α作为配体从而... 目的分析转化生长因子α(Transforing growth factorα,TGF-α)对人体鼻咽癌细胞株CNE2特征性差异蛋白质组的影响,研究并探讨表皮生长因子受体(EGFR)在人鼻咽癌中的作用信号途径。方法将人鼻咽癌CNE2细胞分为两组,以TGF-α作为配体从而激活EGFR信号通路,有TGF-α作用的为观察组,无TGF-α作用的为对照组,通过无血清细胞培养法对其进行培养24h,利用比较蛋白质组学的方法对两组细胞蛋白质表达谱的差异进行分析,鉴定两组特征性差异蛋白质。结果通过双向凝胶电泳以及基质辅助激光解吸飞行时间质谱(MALDI-TOF-MS)技术验证得到包括Triosephosphate isomerase、EF-Tu precursor、Nucleoside-diphosphate kinase、Hemoglobin beta chain、Annexin A1等15种特征性差异蛋白在观察组及对照组中存在差异,它们在信号转导、鼻咽癌细胞的凋亡、侵袭中扮演着重要作用。结论 EGFR可能是通过以上特征性差异蛋白所介导的信号转导从而发挥作用,促进了鼻咽癌细胞的凋亡、侵袭等体外移动效果的改变。 展开更多
关键词 鼻咽癌 TGF-Α 表皮生长因子受体 体外移动 特征性差异蛋白质
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3种保虫宿主日本血吸虫特征性差异表达基因的筛选与验证
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作者 杨健美 石耀军 +7 位作者 冯新港 傅志强 苑纯秀 刘金明 洪炀 李浩 陆珂 林矫矫 《中国血吸虫病防治杂志》 CAS CSCD 2012年第3期279-283,共5页
目的筛选日本血吸虫3种重要保虫宿主来源虫体的特征性差异表达基因,寻找可以用于鉴别这3种宿主来源虫体的遗传标记。方法日本血吸虫尾蚴人工感染黄牛、水牛和山羊,收集感染后49 d成虫,分别抽提RNA,逆转录成cD NA,体外转录为cRNA并进行... 目的筛选日本血吸虫3种重要保虫宿主来源虫体的特征性差异表达基因,寻找可以用于鉴别这3种宿主来源虫体的遗传标记。方法日本血吸虫尾蚴人工感染黄牛、水牛和山羊,收集感染后49 d成虫,分别抽提RNA,逆转录成cD NA,体外转录为cRNA并进行片段化;采用定制的血吸虫芯片分别进行杂交,筛选每种宿主来源虫体的特征性差异表达基因。采用实时定量PCR法对所筛选差异表达基因的表达水平做进一步测定,验证芯片数据的结果,并对这些特征性差异表达基因进行验证。结果通过芯片杂交,分析筛选获得实验黄牛组来源虫体特征性差异表达基因3个,水牛组来源虫体4个,山羊组来源虫体7个。其中黄牛组2个、水牛组3个、山羊组5个特征性差异表达基因在另一批次3种宿主来源虫体的重复试验中得到验证。结论芯片杂交筛选出10个3种宿主来源虫体的特征性差异表达基因,这些基因可能可以作为这3种不同宿主来源虫体的遗传标记。 展开更多
关键词 日本血吸虫 保虫宿主 芯片 特征性差异表达基因
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基于代谢组学的南方菟丝子和金灯藤质量比较研究 被引量:2
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作者 韩颖 徐金娣 +5 位作者 孔铭 朱贺 周姗姗 周桂荣 李松林 毛茜 《中国野生植物资源》 CSCD 2022年第4期1-9,共9页
目的:比较研究南方菟丝子和金灯藤的化学成分,对差异性成分进行定量。方法:采用基于UPLC-QTOFMS/MS的代谢组学方法对南方菟丝子和金灯藤中小分子化学轮廓进行表征,利用多变量数据统计方法发现各自的特征性成分,整合HPLC-UV方法对45批南... 目的:比较研究南方菟丝子和金灯藤的化学成分,对差异性成分进行定量。方法:采用基于UPLC-QTOFMS/MS的代谢组学方法对南方菟丝子和金灯藤中小分子化学轮廓进行表征,利用多变量数据统计方法发现各自的特征性成分,整合HPLC-UV方法对45批南方菟丝子和金灯藤商品药材差异性成分进行定量分析。结果:南方菟丝子和金灯藤化学轮廓有明显差异,南方菟丝子特征性成分为金丝桃苷、紫云英苷、异槲皮苷和山奈酚,金灯藤特征性成分为咖啡酸、3,4-二咖啡酰奎宁酸、4,5-二咖啡酰奎宁酸和绿原酸;8个差异性成分定量表明,南方菟丝子中黄酮类成分为金灯藤的21.5倍,金灯藤中有机酸成分是南方菟丝子的2.8倍;34批南方菟丝子中金丝桃苷含量均达到2020版药典标准要求,但11批金灯藤中金丝桃苷含量均未达到药典标准要求。结论:法定品种南方菟丝子和混淆品金灯藤的小分子化学轮廓、特征性成分及其含量均有明显差异,金灯藤作为菟丝子基原使用的合理性仍需药效等多方面的系统研究。 展开更多
关键词 南方菟丝子 金灯藤 代谢组学 超高液相色谱-四极杆飞行时间质谱联用 特征性差异成分 质量比较
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Characteristic differences in essential oil composition of six Zanthoxylum bungeanum Maxim.(Rutaceae) cultivars and their biological significance 被引量:7
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作者 Shu-ming LIU Shi-jun WANG +3 位作者 Si-yao SONG Yong ZOU Jun-ru WANG Bing-yin SUN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2017年第10期917-920,共4页
Great variations have been found in composition and content of the essential oil of Zanthoxylum bungeanum Maxim. (Rutaceae), resulting from vari- ous factors such as harvest time, drying and extraction methods (Hua... Great variations have been found in composition and content of the essential oil of Zanthoxylum bungeanum Maxim. (Rutaceae), resulting from vari- ous factors such as harvest time, drying and extraction methods (Huang et al., 2006; Shao et al., 2013), sol- vent and herbal parts used (Zhang, 1996; Cao and Zhang, 2010; Wang et al., 2011). However, in terms of artificial introduction and cultivation, there is little research on the chemical composition of essential oil extracted from Z. bungeanum Maxim. 展开更多
关键词 花椒栽培种 挥发油 组成 特征性差异 气相色谱法-质谱法联用法(GC-MS) 聚类分析
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教育对于小时工资的结构性影响
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作者 张卫国 《中国社会科学文摘》 2018年第2期154-154,共1页
根据中国家庭动态跟踪调查2012年的调查数据,针对城市劳动力和农村劳动力之间的小时工资差异进行Oaxaca-Blinder分解和分位数回归及分解。结果表明,城乡小时工资差异的68.22%是可以从受教育程度、婚姻状况、性别等设定的变量的特征性差... 根据中国家庭动态跟踪调查2012年的调查数据,针对城市劳动力和农村劳动力之间的小时工资差异进行Oaxaca-Blinder分解和分位数回归及分解。结果表明,城乡小时工资差异的68.22%是可以从受教育程度、婚姻状况、性别等设定的变量的特征性差异来解释的。 展开更多
关键词 小时工资 农村劳动力 结构性影响 工资差异 分位数回归 调查数据 中国家庭动态跟踪调查 特征性差异
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Physical and chemical characteristics of PM_(2.5) and its toxicity to human bronchial cells BEAS-2B in the winter and summer 被引量:2
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作者 Hui-hui ZHANG Zheng LI +5 位作者 Yu LIU Ping XINAG Xin-yi CUI Hui YE Bao-lan HU Li-ping LOU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2018年第4期317-326,共10页
With the increasing occurrence of haze during the summer, the physicochemical characteristics and toxicity differences in PM2.5 in different seasons are of great concern. Hangzhou is located in an area that has a subt... With the increasing occurrence of haze during the summer, the physicochemical characteristics and toxicity differences in PM2.5 in different seasons are of great concern. Hangzhou is located in an area that has a subtropical monsoon climate where the humidity is very high during both the summer and winter. However, there are limited studies on the seasonal differences in PM2.5 in these weather conditions. In this test, PM2.5 samples were collected in the winter and summer, the morphology and chemical composition of PM2.5 were analyzed, the toxicity of PM2.5 to human bronchial cells BEAS-2B was compared, and the correlation between PM2.5 toxicity and the chemical compo- sition was discussed. The results showed that during both the winter and summer, the main compounds in the PM2.5 samples were water-soluble ions, particularly SO4^2-, NO3^-, and NH4^+, followed by organic components, while heavy metals were present at lower levels. The higher the mass concentration of PM2.5, the greater its impact on cell viability and ROS levels. However, when the mass concentration of PM2.5 was similar, the water extraction from the summer samples showed a greater impact on BEAS-2B than that from the winter samples. The cytotoxicity of PM2.5 was closely associated with heavy metals and organic pollutants but less related to water-soluble ions. 展开更多
关键词 PM2.5 Seasonal difference Physical and chemical characteristics CYTOTOXICITY
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Regional differences in crustal structure of the North China Craton from receiver functions 被引量:20
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作者 WEI ZiGen CHU RiSheng CHEN Ling 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第12期2200-2210,共11页
Moho depth and crustal average Poisson's ratio for 823 stations are obtained by H-n: stacking of receiver functions. These, to- gether with topography and receiver function amplitude information, were used to study ... Moho depth and crustal average Poisson's ratio for 823 stations are obtained by H-n: stacking of receiver functions. These, to- gether with topography and receiver function amplitude information, were used to study the crustal structure beneath the North China Craton (NCC). The results suggest that modified and preserved crust coexist beneath the craton with generally Airy-type isostatic equilibrium. The equilibrium is relatively low in the eastern NCC and some local areas in the central and western NCC, which correlates well with regional geology and tectonic features. Major differences in the crust were observed beneath the eastern, central, and western NCC, with average Moho depths of 33, 37, and 42 km and average Poisson's ratios of 0.268, 0.267 and 0.264, respectively. Abnormal Moho depths and Poisson's ratios are mainly present in the rift zones, the northern and southern edges of the central NCC, and tectonic boundaries. The crust beneath Ordos retains the characteristics of typical craton. Poisson's ratio increases roughly linearly as Moho depth decreases in all three parts of the NCC with different slopes. Receiver function amplitudes are relatively large in the northern edge of the eastern and central NCC, and small in and near the rifts. The Yanshan Mountains and southern part of the Shanxi rift show small-scale variations in the receiver-function ampli- tudes. These observations suggest that overall modification and thinning in the crust occurred in the eastern NCC, and local crustal modification occurred in the central and westem NCC. Different crustal structures in the eastern, central, and western NCC suggest different modification processes and mechanisms. The overall destruction of the crustal structure in the eastern NCC is probably due to the westward subduction of the Pacific Plate during the Meso-Cenozoic time; the local modifications of the crust in the central and western NCC may be due to repeated reactivations at zones with a heterogeneous structure by successive thermal-tectonic events during the long-term evolution of the NCC. 展开更多
关键词 North China Craton Moho depth Poisson's ratio gravitational equilibrium receiver function amplitude regional difference in crust
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A critical evaluation of subjective ratings: Unacquainted observers can reliably assess certain personality traits
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作者 Matthew B.PETELLE Daniel T.BLUMSTEIN 《Current Zoology》 SCIE CAS CSCD 2014年第2期162-169,共8页
Methods to measure consistent individual differences in behavior (i.e. animal personality) fall into two categories, subjective ratings and behavioral codings. Ratings are seldom used despite being potentially more ... Methods to measure consistent individual differences in behavior (i.e. animal personality) fall into two categories, subjective ratings and behavioral codings. Ratings are seldom used despite being potentially more efficient than codings. One potential limitation for the use of ratings is that it is assumed that long-term observers or experts in the field are required to score individuals. This can be problematic in many cases, especially for long-term ecological studies where there is high turnover in personnel. We tested whether raters who were unacquainted with subjects could produce reliable and valid personality assessments of yellow-bellied marmots Marmota flaviventris. Two raters, previously unacquainted with individuals and marmot be- havior, scored 130 subjects on fifteen different adjectives in both open-field (OF) and mirror image stimulation (MIS) trials. Eight OF and nine MIS adjectives were reliable as indicated by both a high degree of intra-observer and inter-observer reliability. Additionally, some ratings were externally valid, correlating with behavioral codings. Our data suggest that activity/exploration and sociability can be a reliable and valid measurement of personality traits in studies where raters were unacquainted with subjects. These traits are observable with the personality tests we used; otherwise researchers using unacquainted raters should be cautious in the tests they employ [Current Zoology 60 (2): 162-169, 2014]. 展开更多
关键词 Animal personality Behavior codings MARMOTS Subjective ratings
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