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The Effect of Simvastatin on mRNA Expression of Transforming Growth Factor-β1,Bone Morphogenetic Protein-2 and Vascular Endothelial Growth Factor in Tooth Extraction Socket 被引量:10
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作者 Chang Liu Zhe Wu Hong-chen Sun 《International Journal of Oral Science》 SCIE CAS CSCD 2009年第2期90-98,共9页
Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (... Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) in the tooth sockets of rat. Methodology Forty-eight male Wistar rats were randomly divided into experimental and control groups (n=24). Polylactic acid/polyglycolic acid copolymer carriers, with or without simvastatin, were implanted into extraction sockets of right mandibular incisors. The expression of TGF-β1, BMP-2 and VEGF mRNA was determined by in situ hybridization in the tooth extraction socket at five days, one week, two weeks and four weeks after implantation. Results The fusiform stroma cells in the tooth extraction socket began to express TGF-β1, BMP-2 and VEGF mRNA in both experimental and control groups from one week after tooth extraction until the end of experiment. The expression of TGF-131 and BMP-2 mRNA in the experimental group was significantly up-regulated after one, two and four weeks, and expression of VEGF mRNA was significantly increased after one and two weeks compared with that in the control group. Conclusion The findings indicate that local administration of simvastatin can influence alveolar bone remodeling by regulating the expression of a school of growth factors which are crucial to osteogenesis in the tooth extraction socket. 展开更多
关键词 bone morphogenetic protein-2 (BMP-2) in situ hybridization SIMVASTATIN tooth extraction socket transforming growth factor-β1 (TGF-β1) vascular endothelial growth factor (VEGF)
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数据清理及其在数据仓库中的应用 被引量:17
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作者 庄晓青 徐立臻 董逸生 《计算机应用研究》 CSCD 北大核心 2003年第6期147-149,共3页
数据仓库是为决策服务的,这里的数据是从各种异构的数据源中采集过来的。由于各个数据源中的数据可能存在错误以及种种不一致性,因而为了确保决策数据的质量必须要对各个数据源中抽取出来的数据进行清理转换。数据清理就是发现数据源中... 数据仓库是为决策服务的,这里的数据是从各种异构的数据源中采集过来的。由于各个数据源中的数据可能存在错误以及种种不一致性,因而为了确保决策数据的质量必须要对各个数据源中抽取出来的数据进行清理转换。数据清理就是发现数据源中数据的错误并加以清除或修改,发现和纠正数据源之间数据的不一致性。分析了数据清理概念和方法以及在数据仓库中的应用。 展开更多
关键词 数据仓库 数据清理 模式冲突 ETL(extraction transformation Loading)
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Reaction condition optimization and kinetic investigation of roasting zinc oxide ore using (NH_4)_2SO_4 被引量:7
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作者 Hong-mei Shao Xiao-yi Shen +2 位作者 Yi Sun Yan Liu Yu-chun Zhai 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2016年第10期1133-1140,共8页
An orthogonal test was used to optimize the reaction conditions of roasting zinc oxide ore using(NH_4)_2SO_4. The optimized reaction conditions are defined as an(NH_4)_2SO_4/zinc molar ratio of 1.4:1, a roasting ... An orthogonal test was used to optimize the reaction conditions of roasting zinc oxide ore using(NH_4)_2SO_4. The optimized reaction conditions are defined as an(NH_4)_2SO_4/zinc molar ratio of 1.4:1, a roasting temperature of 440°C, and a thermostatic time of 60 min. The molar ratio of(NH_4)_2SO_4/zinc is the most predominant factor and the roasting temperature is the second significant factor that governs the zinc extraction. Thermogravimetric-differential thermal analysis was used for(NH_4)_2SO_4 and zinc mixed in a molar ratio of 1.4:1 at the heating rates of 5, 10, 15, and 20 K·min-1. Two strong endothermic peaks indicate that the complex chemical reactions occur at approximately 290°C and 400°C. XRD analysis was employed to examine the transformations of mineral phases during roasting process. Kinetic parameters, including reaction apparent activation energy, reaction order, and frequency factor, were calculated by the Doyle-Ozawa and Kissinger methods. Corresponding to the two endothermic peaks, the kinetic equations were obtained. 展开更多
关键词 zinc ore treatment extractive metallurgy kinetic studies reaction mechanisms phase transformation reaction conditions
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Refreshing File Aggregate of Distributed Data Warehouse in Sets of Electric Apparatus
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作者 于宝琴 王太勇 +3 位作者 张君 周明 何改云 李国琴 《Transactions of Tianjin University》 EI CAS 2006年第3期174-179,共6页
Integrating heterogeneous data sources is a precondition to share data for enterprises. Highly-efficient data updating can both save system expenses, and offer real-time data. It is one of the hot issues to modify dat... Integrating heterogeneous data sources is a precondition to share data for enterprises. Highly-efficient data updating can both save system expenses, and offer real-time data. It is one of the hot issues to modify data rapidly in the pre-processing area of the data warehouse. An extract transform loading design is proposed based on a new data algorithm called Diff-Match,which is developed by utilizing mode matching and data-filtering technology. It can accelerate data renewal, filter the heterogeneous data, and seek out different sets of data. Its efficiency has been proved by its successful application in an enterprise of electric apparatus groups. 展开更多
关键词 distributed data warehouse Diff-Match algorithm KMP algorithm file aggregates extract transform loading
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Economic Bankruptcy of the Industries in Mato Grosso,Brazil
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作者 Dilamar Dallemole Jose Ramos Pires Manso Katiane Toldi 《Chinese Business Review》 2020年第2期55-71,共17页
Data from the Commercial Registry of the Mato Grosso State(JUCEMAT)indicate that the number of bankrupted industries exceeded 16 thousand between 2006 and 2016.This is a high number,to the point of questioning which p... Data from the Commercial Registry of the Mato Grosso State(JUCEMAT)indicate that the number of bankrupted industries exceeded 16 thousand between 2006 and 2016.This is a high number,to the point of questioning which particularities are related with the economic bankruptcy in the State.The objective of this study is precisely to analyse the profile of these industries that closed their activities in Mato Grosso,considering the estimated survival rate for the extraction and transformation segments.Also,based on the underlying indicators of factor analysis,the crucial factors for the economic bankruptcy of micro and small enterprises in the state are delineated.The main results point to the generalized consequences arising from the main economic crises,with more aggressive effects for the microenterprises of sand,gravel,and cobble extraction.Aggravated problems included also the food and logging industries,the main activities of the local economy,with more pronounced impacts in the South,Southeast,North and Central-North regions of Mato Grosso.The survival rate declined considerably between 2006 and 2008 and,despite recovery in the following period,it has not yet recovered its best performance.In the case of micro and small transformation industries,the results point to a group with limited managerial capacity and lack of strategic planning before the execution of the main stages of production and commercialization. 展开更多
关键词 economic bankruptcy survival rate factor analysis extraction and transformation industries Mato Grosso
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Assessment of malathion and its effects on leukocytes in human blood samples
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作者 Amit Kumar Sharma Udita Tiwari +1 位作者 Mulayam Singh Gaur Rajeev Kumar Tiwari 《The Journal of Biomedical Research》 CAS CSCD 2016年第1期52-59,共8页
In the present paper,we report a reproducible,cost effective,fast response method for detection of malathion and its effects on leukocytes in different human blood groups.Spectroscopic methods(UV-Vis spectrometry)an... In the present paper,we report a reproducible,cost effective,fast response method for detection of malathion and its effects on leukocytes in different human blood groups.Spectroscopic methods(UV-Vis spectrometry)and Fourier transform infrared coupled with solid phase extraction were applied for analyzing malathion content in human blood plasma.The spiking levels of malathion in the range of 0.1-1.7μg/mL were extracted from blood plasma samples using SPE.The present active functional groups(C=0;P-O-C;-OH;P=S)were also characterized.The recovery rate of malathion was 80%±4.5%.The calculated correlation coefficient was 0.9799,indicating the linearity of the results.The limit of detection(LOD)and limit of quantification(LOQ)were(0.1-1.7)μg/mL and(0.3-1.5)μg/mL,respectively.Malathion〈1.0μg/mL showed no significant change while higher levels of malathion exposure(1.5μg/mL and 3.0|ig/mL)reduced the number of white blood cells.In conclusion,the spectroscopic results may be useful to understand the mechanism of other pesticides such as methyl parathion and parathion. 展开更多
关键词 leukocytes malathion solid phase extraction UV-Vis spectroscopy Fourier transform infrared chromatography
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Application of wavelet transform in feature extraction and pattern recognition of wideband echoes 被引量:8
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作者 ZHAO Jianping HUANG Jianguo ZHANG Huafeng(College of Marine Engineering, Northwestern Polytechnical University Xi’an 710072) 《Chinese Journal of Acoustics》 1998年第3期213-220,共8页
A novel approach to extract edge features from wideband echo is proposed. The set of extracted features not only represents the echo waveform in a concise way, but also is sufficient and well suited for classification... A novel approach to extract edge features from wideband echo is proposed. The set of extracted features not only represents the echo waveform in a concise way, but also is sufficient and well suited for classification of non-stationary echo data from objects with different property.The feature extraction is derived from the Discrete Dyadic Wavlet Transform (DDWT) of the echo through the undecimated algorithm. The motivation we use the DDWT is that it is time-shift-invariant which is beneficial for localization of edge, and the wavelet coefficients at larger scale represent the main shape feature of echo, i.e. edge, and the noise and modulated high-frequency components are reduced with scale increased. Some experimental results using real data which contain 144 samples from 4 classes of lake bottoms with different sediments are provided. The results show that our approach is a prospective way to represent wideband echo for reliable recognition of nonstationary echo with great variability. 展开更多
关键词 MALLAT IEEE SP Application of wavelet transform in feature extraction and pattern recognition of wideband echoes
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Temperature-variable high-frequency dynamic modeling of PIN diode
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作者 叶尚斌 张佳佳 +1 位作者 张逸成 姚勇涛 《Journal of Semiconductors》 EI CAS CSCD 2016年第4期82-87,共6页
The PIN diode model for high frequency dynamic transient characteristic simulation is important in conducted EMI analysis. The model should take junction temperature into consideration since equipment usually works at... The PIN diode model for high frequency dynamic transient characteristic simulation is important in conducted EMI analysis. The model should take junction temperature into consideration since equipment usually works at a wide range of temperature. In this paper, a temperature-variable high frequency dynamic model for the PIN diode is built, which is based on the Laplace-transform analytical model at constant temperature. The relationship between model parameters and temperature is expressed as temperature functions by analyzing the physical principle of these parameters. A fast recovery power diode MUR1560 is chosen as the test sample and its dynamic performance is tested under inductive load by a temperature chamber experiment, which is used for model parameter extraction and model verification. Results show that the model proposed in this paper is accurate for reverse recovery simulation with relatively small errors at the temperature range from 25 to 120 ℃. 展开更多
关键词 PIN diode Laplace transform temperature variable model parameter extraction
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