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一种廉价的键盘扩展解决方案 被引量:3
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作者 庞(山严)英 cao +1 位作者 Hai-jian 曹海建 《青岛大学学报(工程技术版)》 CAS 2005年第1期91-93,共3页
AT89C2051单片机I/O口较少,若采用一般的键盘接口方法,则占用I/O口较多。为此,提出了一种利用内置模拟比较器构成A/D转换器的键盘扩展方案。以4×4矩阵键盘为例进行了分析,讨论了电阻值的选择问题和解决的方法。这种方案仅占用了单... AT89C2051单片机I/O口较少,若采用一般的键盘接口方法,则占用I/O口较多。为此,提出了一种利用内置模拟比较器构成A/D转换器的键盘扩展方案。以4×4矩阵键盘为例进行了分析,讨论了电阻值的选择问题和解决的方法。这种方案仅占用了单片机的3个引脚,除了电阻和按键之外不需要任何其他硬件。经实际验证,这种键盘扩展方案,简单实用,特别适用于小型的廉价系统。 展开更多
关键词 AT89C2051 模拟比较器 ∑-△ 键盘扩展
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碳酸盐质砾岩致密油成藏主控因素研究——以束鹿凹陷沙河街组沙三下亚段砾岩储层为例 被引量:2
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作者 曹晓峰 陈朝兵 +7 位作者 李静 吕宏玖 张玉川 谢杰 王亮 李云峰 焦立芳 朱玉双 《西北地质》 CAS CSCD 北大核心 2021年第2期187-202,共16页
通过地震、测井、岩心及分析测试等资料,探讨了碳酸盐质砾岩致密油的成藏特征及主控因素,明确了砾岩致密油的有利勘探方向。结果表明,束鹿凹陷沙三下亚段的砾岩具有陆源和内源混源特征,与砾岩呈互层接触的泥灰岩烃源岩厚度大、分布广、... 通过地震、测井、岩心及分析测试等资料,探讨了碳酸盐质砾岩致密油的成藏特征及主控因素,明确了砾岩致密油的有利勘探方向。结果表明,束鹿凹陷沙三下亚段的砾岩具有陆源和内源混源特征,与砾岩呈互层接触的泥灰岩烃源岩厚度大、分布广、有机质丰度高,为砾岩致密油的成藏提供了物质基础;断层对砾岩致密油成藏的影响有弊有利。优质烃源岩、储层发育程度及有利反向断层圈闭是砾岩致密油成藏的主控因素,成藏模式为“源-储共生”型。建议下一步勘探重点为靠近泥灰岩生烃中心、远离断层发育带并位于坡折带附近的滑塌扇成因砾岩体。 展开更多
关键词 成藏模式 断层 烃源岩 致密油 碳酸盐质砾岩 束鹿凹陷
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青藏高原不同生态环境下冰川棘豆(Oxytropis glacialis)内生细菌多样性研究 被引量:4
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作者 许国琪 刘怡萱 +1 位作者 曹鹏熙 刘星 《高原科学研究》 CSCD 2020年第1期20-29,共10页
植物内生菌(Endophyte)有助于宿主植物生存与扩散。文章利用高通量测序技术,对青藏高原高寒草原区(TAS)和灌丛草甸区(TAM)冰川棘豆内生细菌多样性进行分析,为疯草类有毒植物的适应性研究提供基础参考。测序得到236205条有效序列,注释到... 植物内生菌(Endophyte)有助于宿主植物生存与扩散。文章利用高通量测序技术,对青藏高原高寒草原区(TAS)和灌丛草甸区(TAM)冰川棘豆内生细菌多样性进行分析,为疯草类有毒植物的适应性研究提供基础参考。测序得到236205条有效序列,注释到476个OTUs,隶属17个门281个属。多样性分析表明,区域间菌群结构无显著性差异。组成分析显示,不同样本间优势菌门均为变形菌门(Proteobacteria),假单胞菌属(Pseudomonas)、Lachnoclostridium 5和泛菌属(Pantoea)等18个菌属为优势菌属。环境分析认为,土壤电导率(EC)、空气CO2浓度(CC)和土壤温度(ST)对菌群结构的差异具有不同程度的显著性影响,56%的优势菌属与环境因子显著相关。功能预测分析认为,KEGG代谢通路和COG各功能相关的基因丰度在不同区域样本间相似,参与多种宿主代谢调控。综上所述,不同区域间冰川棘豆内生细菌菌群结构及功能的宿主保守性大于地域特异性,在宿主植物中参与各种代谢网络调控。相对稳定的菌群结构及优势菌属丰度随环境显著变化,这有利于冰川棘豆在不同的生态环境中生存和扩散。 展开更多
关键词 冰川棘豆 植物内生细菌 16S rRNA 土壤理化因子 PICRUSt KEGG COG
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微波预处理对超临界CO2脱除绿茶中咖啡因和EGCG影响的研究 被引量:7
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作者 YU Hua-zhong +8 位作者 ZHOU Dong-wu LI Guo-zhang cao Yong LIU Sheng-kai 龙维珍 《茶叶科学》 CAS CSCD 北大核心 2005年第3期203-207,共5页
本文通过对茶叶进行微波预处理和空白对照作对比,探讨了在微波预处理条件下超临界CO2(SC-CO2)技术对茶叶中咖啡因和表没食子儿茶素没食子酸酯(EGCG)的影响,并通过正交实验确定了超临界CO2技术脱除茶叶中咖啡因的最佳工艺参数.结果表明,... 本文通过对茶叶进行微波预处理和空白对照作对比,探讨了在微波预处理条件下超临界CO2(SC-CO2)技术对茶叶中咖啡因和表没食子儿茶素没食子酸酯(EGCG)的影响,并通过正交实验确定了超临界CO2技术脱除茶叶中咖啡因的最佳工艺参数.结果表明,利用微波预处理的方法能明显提高茶叶中咖啡因的脱除率,而对EGCG损失的影响则较小;正交实验中,影响咖啡因脱除率主要因素的依次顺序为萃取压力>萃取温度>夹带剂用量>茶叶含水量. 展开更多
关键词 超临界CO2 微波预处理 茶叶 咖啡因 EGCG
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Experimental Study on Heterograft of Glomus Cells of Carotid Body for Hemiparkinsonian Rats 被引量:2
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作者 cao Xuebing(曹学兵) +3 位作者 SUN Shenggang(孙圣刚) TONG E'tang(童萼塘) 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2002年第2期129-131,共3页
Summary: To observe the effects of heterograft of glomus cells of carotid body on hemiparkinsonian rat models, rats with unilateral 6-hydroxydopamine (6-OHDA)-induced lesions of the right dopaminergic neurons of subs... Summary: To observe the effects of heterograft of glomus cells of carotid body on hemiparkinsonian rat models, rats with unilateral 6-hydroxydopamine (6-OHDA)-induced lesions of the right dopaminergic neurons of substantia nigra received intrastriatal glomus cells heterograft. Apomorphine-induced rotation was monitored for 30 min at various time points after grafting. The striata were cut and examined for dopamine content by HPLC and for immunohistochemical staining of tyrosine hydroxylase positive neurons (TH +) at the end of the experiments. The results showed that apomorphine-induced rotational behavior was significantly reduced for 12 weeks and the dopamine contents were significantly elevated after grafting (P<0.01), and TH + cells survived better. The present study demonstrates that intrastriatal heterograft of glomus cells within carotid body in rats with 6-OHDA-elicited lesions could reduce apomorphine-induced rotational behavior and elevate the dopamine contents and numbers of TH + cell surviving within striatum, and can serve as a new and effective alternative for Parkinson disease. 展开更多
关键词 carotid body glomus cell heterograft Parkinson disease
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Development and Experimental Research of kW-scale Molten Carbonate Fuel Cells 被引量:3
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作者 沈承 Zhu +2 位作者 Xinjian cao Guangyi 《High Technology Letters》 EI CAS 2002年第1期86-91,共6页
A kW-scale molten carbonate fuel cells stack was developed and 800-hours’ operating test and performance experimental research had been done. Utilizing domestic materials completely, we developed NiO cathode and Ni-A... A kW-scale molten carbonate fuel cells stack was developed and 800-hours’ operating test and performance experimental research had been done. Utilizing domestic materials completely, we developed NiO cathode and Ni-Al anode with the active area of 336cm 2 and Υ-LiAlO 2 electrolyte tile and bipolar plate with the area of 900cm 2. The stack was composed of thirty cells, with 62%Li 2CO 3+38%K 2CO 3 as its electrolyte. During the 800 hours’ continuous operating, the performance of the stack was stable. With 99.7%(mole fraction) H 2 as fuel and O 2 from air as oxidant, the average operating voltage of a cell was about 0.72 V. The maximal current density attained to 165mA/cm 2, and the maximal output power attained to 1080 Watt. The whole performance of the stack approached to the international level in the early 90’s. This paper gives the main works and experiments results. 展开更多
关键词 燃料电池 千瓦级 熔化碳化燃料电池 实验研究
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The Weak Interaction on CO_2...CO van der Waals Complex: A Theoretical Study 被引量:1
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作者 cao Zhao-hua +2 位作者 BU Yu-xiang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第1期94-99,共6页
The geometries of van der Waals complex CO 2...CO were optimized at DFT and second order Moller Plesset perturbation(MP2) levels with the large basis set, three stable structures were found. The most stable structu... The geometries of van der Waals complex CO 2...CO were optimized at DFT and second order Moller Plesset perturbation(MP2) levels with the large basis set, three stable structures were found. The most stable structure has a T shape geometry in which the CO lies along the C 2 axis of CO 2, with the two C atoms direct contact and R (C...C)=0 3227 nm. The corresponding energies of the most stable structure were calculated by means of MP2, MP4D, MP4DQ, MP4SDTQ, MP4SDQ, CCSD and CCSD(T) methods. The BSSE(basis set superposition error) was eliminated by the Boys Bernardi counterpoise correction(CP) method. According to thermodynamics data, van der Waals complex CO 2...CO can be found at a low temperature and/or a high pressure. There is a little charge transferred between the two interacted subunits. In the most stable structure, CO 2 is the acceptor and CO is the donor. 展开更多
关键词 CO 2...CO van der Waals complex Weak interaction MP2 calculation DFT calculation
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Expression of c-erbB2 in Gestational Trophoblastic Disease and Its Clinical Significance 被引量:1
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作者 WANG Yuxia(王玉霞) +3 位作者 cao Yang(曹阳) SUN Yongyu(孙永玉) 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2002年第2期123-125,共3页
Summary: In order to explore a potential indicator of predicting the occurrence and development of gestational trophoblastic tumor, the expression of c-erbB2 oncogene in human normal placenta, hydatidiform mole and ch... Summary: In order to explore a potential indicator of predicting the occurrence and development of gestational trophoblastic tumor, the expression of c-erbB2 oncogene in human normal placenta, hydatidiform mole and choriocarcinoma was investigated. The expression of c-erbB2 was detected immunohistochemically by monoclonal antibody against the gene on the formalin-fixed paraffin sections of 21 hydatidiform moles, 21 invasive moles, 20 choriocarcinomas and 30 normal placentas. Results showed that the expression level of c-erbB2 was significantly higher in gestational trophoblastic tumor than in hydatidiform mole and normal placenta of midterm and term pregnancy (P<0.05), while there was no significant difference between patients with gestational trophoblastic tumor of stage Ⅲ, Ⅳ and those of stage Ⅰ, Ⅱ. It was demonstrated that overexpression of c-erbB2 may closely associated with malignant transformation of hydatidiform mole, not only providing important insight into pathogenesis of gestational trophoblastic tumor, but also having an important significance for the early diagnosis and early treatment of gestational trophoblastic tumor. 展开更多
关键词 c-erbB2 oncogene PLACENTA trophoblastic tumor
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Design of House Keeping System for a Certain Micro Satellite 被引量:1
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作者 马秀娟 cao +4 位作者 Xibin Xu Guodong Ma Xingrui 《High Technology Letters》 EI CAS 2001年第4期69-72,共4页
This paper presents the design of hardware and software of the house keeping system for a certain micro satellite. The system uses micro electronic technique, large scale integrated circuits, processors and computers ... This paper presents the design of hardware and software of the house keeping system for a certain micro satellite. The system uses micro electronic technique, large scale integrated circuits, processors and computers which has the advantages of strong function, high flexibility and reliability, It satisfies the requirements for efficient performance,light weight, small volume,and low consumption of power for micro satellite. 展开更多
关键词 House keeping system Hardware structure Software design
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古代儒家伦理道德中的和谐性思想浅析 被引量:3
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作者 曹显光 cao Xianguang 《楚雄师范学院学报》 2004年第6期62-64,共3页
在古代, 儒家伦理道德能够深入人心, 很大程度上得益于其思想具有和谐性品质。儒家和谐性思想体现在基本伦理要求上, 体现在个体与社会利益关系上, 体现在道德修养方式尤其是身心修养上, 体现在注重个人内心体验上。由于时代的局限性, ... 在古代, 儒家伦理道德能够深入人心, 很大程度上得益于其思想具有和谐性品质。儒家和谐性思想体现在基本伦理要求上, 体现在个体与社会利益关系上, 体现在道德修养方式尤其是身心修养上, 体现在注重个人内心体验上。由于时代的局限性, 儒家和谐性思想也有不足。儒家是中国文化的传统, 当代中国的道德建设应该借鉴其和谐性思想, 并且克服那些不适应时代发展的方面。 展开更多
关键词 儒家 和谐性 道德
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GSNOR依赖的PPARγ去亚硝基化参与调控间质干细胞的脂肪、骨质分化平衡
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作者 cao 李婧 《生理科学进展》 CAS CSCD 北大核心 2015年第4期303-303,共1页
骨髓来源的间质干细胞(mesenchymal stem cells,MSCs)可分化为脂肪细胞和成骨细胞,二者分化平衡受到过氧化物酶体增殖物激活受体(peroxisome proliferator-activated receptorγ,PPARγ)的调控,然而PPARγ对该过程的具体调节机制尚... 骨髓来源的间质干细胞(mesenchymal stem cells,MSCs)可分化为脂肪细胞和成骨细胞,二者分化平衡受到过氧化物酶体增殖物激活受体(peroxisome proliferator-activated receptorγ,PPARγ)的调控,然而PPARγ对该过程的具体调节机制尚不清楚。MSCs向脂肪细胞和成骨细胞的不均衡分化可导致多种疾病,如骨质疏松症、异位骨形成、代谢性疾病等,而PPARγ作为MSCs分化调节的关键因子在多种层面影响这一生理过程。 展开更多
关键词 PPAR 间质干细胞 GSNOR 亚硝基化 脂肪细胞 异位骨 骨髓来源 PEROXISOME 成骨细胞 代谢性疾病
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羧酸酯、硫代乙酸酯的合成新法
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作者 cao YQ 吕娜(摘) 《中国医药工业杂志》 CAS CSCD 北大核心 2008年第5期327-327,共1页
卤代烃与羧酸钠盐或硫代乙酸钠盐不加溶媒,在PEG400中反应生成相应的酯。羧酸酯(65~70℃,2~10h)22例收率76%~95%(仲丁酯和叔丁酯各1例,68%和41%);硫代乙酸酯(室温,1.5~4h)10例收率62%~95%。
关键词 硫代乙酸 羧酸酯 乙酸酯 合成 PEG400 羧酸钠盐 叔丁酯 卤代烃
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Recurrence anomaly of ground water behavior before strong earthquakes in North China
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作者 cao Xin-lai(曹新来) +1 位作者 BIAN Qing-kai(边庆凯) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第z1期163-171,共9页
By analyzing the relationship between ground water behavior and strong seismic activity during the past more than 20 years in North China, we have found similar water level descending variation of a part of wells in ... By analyzing the relationship between ground water behavior and strong seismic activity during the past more than 20 years in North China, we have found similar water level descending variation of a part of wells in the short-term stage before several strong earthquakes. The characteristics of anomaly are: at the beginning, water level dropped abruptly or accelerated to drop; then it turned to slow rising with a smaller amplitude than that of descending; earthquakes occurred during the slow-rising process of water level, and at that time or before earthquake occurrence, water level rose with a large amplitude. Among more than 100 wells in North China, the descending anomalies were not recorded for many times, but similar variation processes of water level were noted at different wells before several strong earthquakes, which proves that seismic precursory anomalies of ground water are of certain recurrence features, occurring repeatedly before different strong earthquakes. Therefore, it is necessary to study the genesis of this type of anomaly and its relationship with strong seismic activity. 展开更多
关键词 North China strong earthquake dynamic state of water level short-term stage RECURRENCE
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POLYMER NETWORK-POLY(ETHYLENE GLYCOL)COMPLEXES WITH SHAPE MEMORY EFFECT
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作者 Yi-ping cao +1 位作者 C.W.Yip 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第1期29-33,共5页
The complexes of poly(methacrylic acid-co-methyl methacrylate) network with poly(ethylene glycol) stabilized byhydrogen bonds were prepared. By introducing the poly(ethylene glycol), a large difference in storage modu... The complexes of poly(methacrylic acid-co-methyl methacrylate) network with poly(ethylene glycol) stabilized byhydrogen bonds were prepared. By introducing the poly(ethylene glycol), a large difference in storage modulus below andabove the glass transition temperature occurred and the complexes exhibited shape memory behaviors. The morphology ofcomplexes was studied by using DSC, WAXD, and DMA. The results indicate that the fixed phase of this kind of novelshape memory materials is the network, and the reversible phase is the amorphous state of PEG:PMAA complex phase. Theshape recoverability almost reaches 100%. This type of complexes can be regarded as a novel shape memory network. 展开更多
关键词 Hydrogen bonded complex Shape memory effect Storage modulus ratio
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Study on Optimizing Thermal Energy Storage Capacity for Heat Supply System
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作者 cao Jiacong(曹家枞) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第2期68-73,共6页
Thermal energy storage (TES) can increase the energetic efficiencies and, in many cases, the exergetic efficiencies of thermal energy systems. Steam boiler plant with a violently fluctuating load is a typical example ... Thermal energy storage (TES) can increase the energetic efficiencies and, in many cases, the exergetic efficiencies of thermal energy systems. Steam boiler plant with a violently fluctuating load is a typical example when a steam accumulator is added to it. While the conparatively big first cost constitutes a barrier to the wide use of TES, the cost will notably be reduced through minimizing the necessary thermal capacity of it JThe structure and illustrations are given for the computer program designed for performing the optimization. This'program was applied to an existing boiler plant equipped with a steam accumulator. The results show that there would have been a big reduction in the necessary capacity, if the design of this steam accumulator had been optimized. Four conclusions have been reached. 展开更多
关键词 THERMAL ENERGY storage optimization efficiency necessary THERMAL capacity
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Variable Structure Control for Unmatched MIMO Nonlinear System with Its Application to MCFC Stacks
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作者 许春山 Sun +4 位作者 Xingjin cao Guangyi Zhu Xinjian 《High Technology Letters》 EI CAS 2004年第3期54-60,共7页
A new Variable Structure Control (VSC) with Rapid-Smooth Reaching Law (RSRL) and Rapid-Convergent Sliding Mode (FCSM) is proposed, which is based on normal VSC system. When it is used to unmatched MIMO nonlinear syste... A new Variable Structure Control (VSC) with Rapid-Smooth Reaching Law (RSRL) and Rapid-Convergent Sliding Mode (FCSM) is proposed, which is based on normal VSC system. When it is used to unmatched MIMO nonlinear system, the authors combine the method of Input/Output Linearizing (I/O L) with VSC: they use the I/O L method to solve the "Unmatched" problem and use the new VSC to get good result of control. After analyzing the robustness of the MIMO nonlinear system, they use this novel controller to the temperature and gas pressure control system of Molten Carbonate Fuel Cell (MCFC) Stacks. Simulation provides quite satisfactory performance with unmatched uncertainties and external disturbances. Its future actual application is practical. 展开更多
关键词 变量结构控制 气压 温度 时间 非线性系统 弹性模型 MCFC 线性化
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Construction and Expression of GST and Carbon Skeleton of Amatoxins Fusion Gene
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作者 赵建 cao +8 位作者 Mei Zhang Jie Hou Ruotong Chen Yaofeng Yang Zhirong 《High Technology Letters》 EI CAS 2004年第1期52-56,共5页
The primer, AT For1, AT For2 and AT Back, are designed and synthesized for adding-PCR that is used to construct the fusion GST-AT gene. Depending on two-time adding-PCR amplification and the insertion of coding sequen... The primer, AT For1, AT For2 and AT Back, are designed and synthesized for adding-PCR that is used to construct the fusion GST-AT gene. Depending on two-time adding-PCR amplification and the insertion of coding sequence of octapeptide carbon skeleton into the 3 terminus of GST gene, the authors get the masculine recon, pGAT-1, confirmed by sequence determination and analysis, whose ORF is read-through. After IPTG induction and partial purification, SDS-PAGE electrophoresis is employed to detect the gene expression. The expressions of total bacterial proteins are about 21.3%, 22.5%, 19.32%, 21.73% in E. coli BL21, DH5α, JM109 and Top10 strains, respectively. Considering the quantity of induced total bacteria, the E. coli BL21 is the best one among the four recipient strains. This article supplies an academic foundation for producing biological active amatoxins. 展开更多
关键词 基因表达 熔合基因 八肽碳骨架 GST 附加PCR法 谷胱甘肽-S-转移酶 毒伞蕈毒素
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An investigation of acarbose effects in PCOS women with postprandial hyperglycemia
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作者 Zheng Jianhuai(郑建淮) +6 位作者 cao Zuansun(曹缵孙) Chen Xiaoyan (陈晓燕) Mao Wenjun(毛文军) 《生殖医学杂志》 CAS 2002年第z1期22-28,共7页
Objectives: To investigate the effects of insulin resistance on serum androgen level and ovulation of women with polycystic ovary syndrome (PCOS) and observe clinic role of acarbose in the treatment of hyperinsulinemi... Objectives: To investigate the effects of insulin resistance on serum androgen level and ovulation of women with polycystic ovary syndrome (PCOS) and observe clinic role of acarbose in the treatment of hyperinsulinemia, postprandial hyperglycemia and anovulation. Methods: 14 women accompanied by postprandial hyperglycemia with PCOS were administrated by acarbose for 12 weeks.14 age-matched individuals who had similar body mass index and normal menstruation were served as controls. Results: Serum T levels declined significantly from 4.09±1.04 nmol/L to 1.71±0.54 nmol/L (P<0.001), after acarbose treatment for 12 weeks. 12 out of 14 cases restored ovulation and menstrual cycles after acarbose treatment, among which 4 got pregnant. Conclusion: Acarbose may play a role on reducing postprandial hyperglycemia and HbAic levels, increase ISI and FSG/FI, indirectly reduce serum androgen levels through reducing plasma insulin level and recover ovarian ovulation in PCOS women with postprandial hyperglycemia. 展开更多
关键词 POLYCYSTIC OVARY syndrome HYPERINSULINEMIA Postprandialhyperglycemia ACARBOSE
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Mutagenic Analysis on the Polyhedrin gene(polh) of Bombyx mori Nuclear Polyhedrosis virus(BmNPV)
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作者 cao Yang +2 位作者 Huang Ya-dong 《癌变.畸变.突变》 CAS CSCD 2001年第4期241-241,共1页
关键词 家蚕 核多角体病毒 polh基因突变 遗传分析
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Application of RS Codes in Decoding QR Code
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作者 朱素霞 Ji +2 位作者 Zhenzhou cao Zhiyan 《High Technology Letters》 EI CAS 2003年第4期67-69,共3页
The QR Code is a 2 dimensional matrix code with high error correction capability. It employs RS codes to generate error correction codewords in encoding and recover errors and damages in decoding. This paper presents ... The QR Code is a 2 dimensional matrix code with high error correction capability. It employs RS codes to generate error correction codewords in encoding and recover errors and damages in decoding. This paper presents several QR Code’s virtues, analyzes RS decoding algorithm and gives a software flow chart of decoding the QR Code with RS decoding algorithm. 展开更多
关键词 RS编码 QR编码 译码算法 快速响应编码 流程图
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