11 resultados para prescription

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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The photorefractive holographic dynamics of grating formation in photochromic doubly doped LiNbO3:Fe:Mn crystal is studied numerically and analytically in terms of the two-center model of Kukhtarev Et al. [Ferroelectrics 22, 949 (1979)]. The relations among the recorded and fixed space-charge fields and the doping densities, the oxidation-reduction states of the fields, and the intensities of UV-sensitizing and red recording beams are studied. Important conditions and effects are feued, and an optimal prescription for material doping and oxidation-reduction processing is suggested in which the crystal can be strongly oxidized and the Mn-doping density is smaller than the Fe-doping density. (C) 2000 Optical Society of America. OCIS codes: 050.7330, 190.5330, 090.2900.

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Traditional Chinese medicine (TCM) is a great treasure of China, the analysis of which is an arduous task. The viewpoint that all chemical constituents of Chinese herbal complex prescription should be analyzed as a black box is elucidated for the first time. Intelligent multi-mode multi-column chromatographic system (IMMCC) with its hybrids is the basic method and HPLC Unified Method is the breakthrough for the black box analysis. Dang-Gui-Bu-Xue-Tang was selected as a typical TCM and a systematic separation method from non-aqueous mobile phase to pure water mobile phase was put forward in order to convert unknown sample to known sample. The a, c values and UV spectra of 66 components of Astragalus, 78 components of Angelica and 71 components of Dang-Gui-Bu-Xue-Tang were obtained. Intelligent optimization and peak identification method and software for complex samples were developed and the optimum multi-step multi-binary gradient curve of mobile phase for Astragalus was ascertained. The maximum error and minimum error of predicted retention time for all components of Astragalus are 8.62% and 0.05% respectively. All components of Astragalus were compared with those of Angelica and it is found that many components of Astragalus are the same as those of Angelica, while the contents of these components are different. Many components of Dang-Gui-Bu-Xue-Tang are also the same as those of Astragalus and Angelica with different contents.

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Immobilized liposome chromatography (ILC), the stationary phase of which has been regarded as a mimic biomembranes system was used to separate and analyze compounds interacting with liposome membrane in Danggui Buxue decoction, a combined prescription of traditional Chinese medicines (CPTCMs), and its compositions Radix Astragli and Radix Angelica Sinensis. More than 10 main peaks in the extract of Danggui Buxue decoction were resolved on the ILC column, suggesting that more than 10 components in the prescription have significant retention on ILC column. Ligustilide, astragaloside, TV and formononetin, three main bioactive ingredients in Danggui Buxue decoction, were found to have relatively significant, while ferulic acid, another bioactive ingredient in the prescription, relatively weak retention on ILC column. Effects of the eluent pH and amount of immobilized phosphatidylcholine (PC) on separation of interactional compounds in the extract of Danggui Buxue decoction were also investigated. It was found that these two factors strongly affected the retention of some interactional compounds. In addition, the fractions partitioned with different solvents from water extract of this combined prescription were evaluated with this ILC column system. (c) 2005 Elsevier B.V. All rights reserved.

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Large-eddy simulation (LES) has emerged as a promising tool for simulating turbulent flows in general and, in recent years,has also been applied to the particle-laden turbulence with some success (Kassinos et al., 2007). The motion of inertial particles is much more complicated than fluid elements, and therefore, LES of turbulent flow laden with inertial particles encounters new challenges. In the conventional LES, only large-scale eddies are explicitly resolved and the effects of unresolved, small or subgrid scale (SGS) eddies on the large-scale eddies are modeled. The SGS turbulent flow field is not available. The effects of SGS turbulent velocity field on particle motion have been studied by Wang and Squires (1996), Armenio et al. (1999), Yamamoto et al. (2001), Shotorban and Mashayek (2006a,b), Fede and Simonin (2006), Berrouk et al. (2007), Bini and Jones (2008), and Pozorski and Apte (2009), amongst others. One contemporary method to include the effects of SGS eddies on inertial particle motions is to introduce a stochastic differential equation (SDE), that is, a Langevin stochastic equation to model the SGS fluid velocity seen by inertial particles (Fede et al., 2006; Shotorban and Mashayek, 2006a; Shotorban and Mashayek, 2006b; Berrouk et al., 2007; Bini and Jones, 2008; Pozorski and Apte, 2009).However, the accuracy of such a Langevin equation model depends primarily on the prescription of the SGS fluid velocity autocorrelation time seen by an inertial particle or the inertial particle–SGS eddy interaction timescale (denoted by $\delt T_{Lp}$ and a second model constant in the diffusion term which controls the intensity of the random force received by an inertial particle (denoted by C_0, see Eq. (7)). From the theoretical point of view, dTLp differs significantly from the Lagrangian fluid velocity correlation time (Reeks, 1977; Wang and Stock, 1993), and this carries the essential nonlinearity in the statistical modeling of particle motion. dTLp and C0 may depend on the filter width and particle Stokes number even for a given turbulent flow. In previous studies, dTLp is modeled either by the fluid SGS Lagrangian timescale (Fede et al., 2006; Shotorban and Mashayek, 2006b; Pozorski and Apte, 2009; Bini and Jones, 2008) or by a simple extension of the timescale obtained from the full flow field (Berrouk et al., 2007). In this work, we shall study the subtle and on-monotonic dependence of $\delt T_{Lp}$ on the filter width and particle Stokes number using a flow field obtained from Direct Numerical Simulation (DNS). We then propose an empirical closure model for $\delta T_{Lp}$. Finally, the model is validated against LES of particle-laden turbulence in predicting single-particle statistics such as particle kinetic energy. As a first step, we consider the particle motion under the one-way coupling assumption in isotropic turbulent flow and neglect the gravitational settling effect. The one-way coupling assumption is only valid for low particle mass loading.

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We report experimental and theoretical studies of nonvolatile photorefractive holographic recording in LiNbO3:Cu:Ce crystals with two illumination schemes: (1) UV light for sensitization and a red interfering pattern for recording and (2) blue light for sensitization and a red pattern for recording. The results show that the oxidized LiNbO3:Cu:Ce crystals can provide high, persistent refractive-index modulation with weak lightinduced scattering. The optimal working conditions and the prescription for doping and oxidation-reduction processing that yields the maximum refractive-index modulation are discussed. (C) 2000 Optical Society of America OCIS codes: 050.7330, 190.5330, 090.2900.

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Three wavelengths of red, green and blue of recording beams are systemically tested for the UV-assistant recording and optical fixing of holograms in a strongly oxidized Ce:Cu:LiNbO3 crystal. Three different photorefractive phenomena are observed. It is shown that the green beams will optimally generate a critical strong nonvolatile hologram with quick sensitivity and the optimal switching technique could be jointly used to obtain a nearly 100% high diffraction. Theoretical verification is given, and a prescription on the doping densities and on the oxidation/reduction states of the material to match a defined recording wavelength for high diffraction is suggested.

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医院信息系统(hospital information system,HIS)作为医院信息化建设的重要组成部分越来越受到社会的重视,已经进入一个高速发展的阶段。但是作为诊疗过程的一个重要组成部分-药物处方治疗,在HIS中却缺少必要的监控与指导。在HIS标准化推进的同时,更应该对其深度和广度进行研究,结合软件工程的设计思想,基于面向对象的开发方法,设计开发了“中药处方配伍”监控系统,提供了临床用药指导功能,使其作为HIS的一个子系统能够实时的对医生处方进行监控,使临床医药人员记得更多、更准、更细,以降低药源性疾病,提高用药质量,加强用药管理,避免医疗纠纷。

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质谱技术以其灵敏度高、样品需求量少、快速准确的特点在生物大分子体系和天然产物的化学成分研究中起着极为重要的作用。特别是软电离质谱技术的发展,大大简化了化合物的测定过程,提高了分析研究速度,为分析植物及食物中的结构信息提供了快速便捷的方法。HPLC-ESI-MSn是90年代发展成熟的分析技术,它集液相色谱的高分离能力与质谱的高灵敏度和高专属性于一体,已成为包括药物微量杂质、药物降解产物、药代代谢动力学研究、组合化学合成产物高通量分析以及天然产物的化学筛选在内的现代药学研究领域最强有力的分析工具之一。本文首先采用电喷雾多级串联质谱技术,系统地研究了负离子条件下黄酮普元、黄酮醇普元以及二氢黄酮普元等化合物的特征质谱行为,并对中药黄芬中三种黄酮昔化合物进行了研究。利用这些特征碎片离子,可以简便快捷的区分结构类似的黄酮类化合物及其同分异构体。通过对黄酮C一昔类化合物的电喷雾串联质谱(ESI-MSn)研究,提出黄酮C-苷类化合物的特征碎裂规律,证明〔M-H-60]-,〔M-H-90]-,〔M-H-120〕-为黄酮C-苷类化合物的特征离子。为鉴定植物粗提物中黄酮类化合物奠定了基础。之后我们进一步采用高效液相色谱与电喷雾质谱联用技术,在线区分混合物中的黄酮类化合物的同分异构体。根据黄酮类化合物的电喷雾质谱规律以及化合物的色谱保留时间分析鉴定了黄答中的七种黄酮类化合物。建立了一种有效检测黄芩(Scutellariabaicalensis Georgi)中黄酮类化合物的快速灵敏的分析方法,为建立黄答药材的质量控制标准提供了借鉴。对于黄酮类化合物灵敏、快速和准确的分析方法的建立,不仅为黄酮类化合物的结构的快速鉴定提供了一定的依据,而且对生药的鉴别和制剂的质控起到重要的作用。利用电喷雾多级串联质谱技术,对化学结构相似的黄酮营、二氢黄酮营和黄酮醇昔类化合物进行了对比研究。并且首次利用高分辨质谱FTICR-MS及SORI-CID技术对naringin进行了质谱研究。利用其超高分辩率、准确质量确证了中性碎片丢失,进一步证明了我们对其碎裂机理的推断。之后,我们通过金属离子与黄酮昔溶液混合后,采用电喷雾串联质潜法进行测定。实验表明通过人为加入某些金属离子如Li+,Na+和K+,特别是Li+可以提高黄酮昔类化合物分析灵敏度,从而提供较多结构信息。并且在串联质谱中表现不同的碎裂行为,为黄酮类化合物结构分析提供补充信息。研究表明结合〔M-H]-,〔M+Na〕+,〔M+Li〕+离子串联质潜提供的信息,能够有效的鉴定黄酮普的结构。本文通过电喷雾串联质谱(ESI-MSn)和液质联机技术(HPLC-ESI-MS/MS)研究了原小聚碱型生物碱。首次利用高分辨质谱FTICR-MS和SORI-CTD技术对原小桨碱型生物碱进行了高分辨质谱研究,提出了各种碎片离子的碎裂途径,并总结了原小聚碱型生物碱的质谱碎裂规律,为鉴定此类型的生物碱提供了依据。之后通过电喷雾串联质谱研究了四种生物碱化合物质谱行为。最后我们利用液质联机技术(HPLC-ESI-MSn),通过与标准品的液相保留时间对照及原小聚碱型生物碱的质谱碎裂规律,建立了分析鉴定常用中药中原小聚碱型生物碱的快捷方法。并通过选择离子监控技术(SIM)提高了对于同分异构体的分离鉴定。通过色谱UV吸收峰定量研究了这四种药用植物中小璧碱和巴马汀的含量,为临床应用提供一定的化学基础,为建立中药质量控制标准及植物分类学提供一定的依据。采用HPLC法考察了常见的黄连药对组合煎煮对黄连中小聚碱、巴马丁煎出量的影响。为制药工艺的优化奠定了基础。之后我们以中药理论为指导,按药物性味对改良半夏泻心汤中各药进行分组,利用高效液相色谱分析了不同配伍条件下小璧碱、巴马丁煎出量的变化。为组方的合理性和科学性提供了一定的化学物质基础依据。

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The intestinal bacterial metabolites of ginsenosides are responsible for the main pharmacological activities of ginseng. The purpose of this study was to find whether these metabolites influence hepatic metabolic enzymes and to predict the potential for ginseng-prescription drug interactions. Utilizing the probe reaction of CYP3A activity, testosterone 6beta-hydroxylation, the effects of derivatives of 20(S)-protopanaxadiol and 20(S)-protopanaxatriol families on CYP3A activity in rat liver microsomes were assayed. Our results showed that ginsenosides from the 20(S)-protopanaxadiol and 20(S)-protopanaxatriol family including Rb-1, Rb-2, Rc, Compound-K, Re, and Rg(1), had no inhibitory effect, whereas Rg(2), 20(S)-panaxatriol and 20(S)-protopanaxatriol exhibited competitive inhibitory activity against CVP3A activity in these microsomes with the inhibition constants (K) of 86.4+/-0.8mum, 1.7+/-0.1mum, and 3.2+/-0.2 mum, respectively. This finding demonstrates that differences in their chemical structure might influence the effects of ginsenosides on CYP3A activity and that ginseng-derived products might have potential for significant ginseng-drug interactions.

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粮食安全关系问题关系着一个国家的稳定与安全,粮食安全是人们一直关注的焦点问题。从全球来讲,世界可耕作土地越来越少,粮食安全是一个很严峻的问题。粮食安全是一个世界性问题,对我国来说,更是一个重大的问题。大力增产粮食,确保粮食安全,是实现世界和平与发展的一项不可忽视的长期而紧迫的任务。中国历朝历代政府都把粮食安全问题放在首位,视仓廪盈实为盛世景象。粮食是安天下的战略产业。改革开放以来,通过体制创新、结构创新和科技创新,粮食生产取得了举世瞩目的成就。论文分析了粮食安全的含义及问题,探讨了粮食安全衡量指标﹑内容及其含义,针对我国粮食安全的实际情况,提出了相应对策。

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In the intermediary and later stage of oil field development, remaining oil disperses fiercely, the contradiction in the layer has become the main problem and the distribution of remaining oil is transforming to the difference of single sand-body. So, the fine description research of reservoir is becoming a tendency and the methods of remaining oil research need new developments. In the research of “The Single-sand-body Architectural Element and Potentiality Analysis Research of Meandering River, GuDao Oil Field”, the research principle is analytical hierarchy process and schema prescription what are reservoir fine description methods under the condition of dense well pattern. The knowledge of regional sedimentary system and sedimentary facies is the foundation of this research. According to the 3D distribution model of the microfacies sand-body of fluvial facies, stratigraphic unit classification & coenocorrelation of 154 wells are completed in the research of meandering river sand-body in Ng3-4. In this research, the 3D distribution of microfacies sand-body in the main layers are settled. The architectural element model of Ng4 point bar is analysed using the drill core and FMI data. According to the overgrow model of point bar, the surfaces of lateral accretion is traced and the architectural element model of point bar is settled. In the research, the control of micro-facies sand-body of meandering river to the distribution of remaining oil is analysed and the potential area is proposed. All these will play an important role in the development of GuDao oil field. In this research, abundant of logging data, drill core data and production performance data are used to analyse the contributing factor of single sand-body in the Ng3-4 meandering river. Using the technology of geological modeling, all that are researched including the 3D distribution scales of meandering river point bar, the control affection of inner lateral accretion layer to the distribution of oil & gas and remaining. Then, the way of remaining oil development in the sand-body of meandering river is improved. The innovation of the research technology includes (1) the presentation of the conception and research methods of micro-facies sand-body (2) enriching the content of reservoir architectural element research and (3) to renew the research method of remaining oil analysis. The research has practiced with obvious effect.(1)It is deepened into understand the river facies reservoir construction of Gudao oil field, By Building the reservoir construction and studying the effect of diffent deposit or geological interface to fluid partition and to the distribution of the remaining oil, we improved the understanding to the distribution of the remaining oil;(2)By building the distribution mod of the remaining oil in the reservoir construction and making the remaining oil description detailed,the development direction of old oil field is more clear;(3)Expanded the application scales of the horizontal well and enhanced the application effects of the horizontal well technique , we designed and drilled 23 ports horizontal wells in all , the cumulative hydrocarbon production is 10.6*104 t;(4) According to the findings of the internal building structure in reservoir of the fluvial facies in the region of interest, and uniting the injection/production corresponding states、the producing history and the dynamic monitoring documents of the oil/water wells in the flooding units , we researched the residual oil distribution in the point bar , and found the distribution regular patterns of the remaining oil, and comprehended the distribution of the remaining oil . In base of that , we proceeded the optimizing designs of the oil well potentialities , and advanced the effect of the treatment potentials . It is proved that , it was very important that internal building structure research of the single sand body of reservoir for guiding the high efficiency potentialities of the remaining oil in the high water cut stage .