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11.
中药有效成分的不同概念   总被引:1,自引:0,他引:1  
目的提出运用中药“有效成分”基本概念来真实反映中药的质量。方法与结果根据对中药“有效成分”的固有概念带来的一些普遍问题,结合相关法规的定义以及近几年科研工作,对“有效成分”的观念更新进行探讨。结论提出了中药“有效成分”不应单单指化学上的单体化合物,通常更多是指来自药材的一些混合物成分,包括了原药材及其经切制、粉碎、炮制、提取及浓缩的任何形式。这个观念才能真实地反映中药的物质基础,有利于中医药业的运作和发展。  相似文献   
12.
目的:通过分析我院应用的含毒性成分中成药的概况,探讨怎样合理应用该类药材.方法:统计、分析我院10年来应用的中成药品种.结果:50种中成药含有毒性成分,其中心脑血管科、骨伤科、消化科、耳鼻喉科使用的中成药中含毒性药材的比例较大(均为14%).结论:应高度重视含毒性成分中成药的应用,通过规范药品说明书、加强对该类药物的不良反应监测、加强中药流行病学研究等措施引起大家的警惕.  相似文献   
13.
Introduction: With the incorporation of edge activators into the lipid bilayer structure, elasticity properties are given to liposomes. Regardless of the debate over the precise permeation mechanism of elastic liposomes, these vesicles have been proven to enhance drug permeation into or through skin in most cases.

Areas covered: This article provides an overview of the formulation ingredients of elastic liposomes and their relationship with skin permeation behavior. The ingredients are divided into two categories of basic and optional ingredients. The effect of stability on permeation behavior of the vesicles is highlighted.

Expert opinion: More attention should be paid to the stability of elastic liposomes. The different stability properties of the elastic liposomes following administration can induce different skin permeation behaviors of the vesicles. It is necessary to select the optimum composition of the elastic liposomes in order to control the stability and permeation behavior of the vesicles into or through the skin. Moreover, for the development of elastic liposomes, particular attention should also be paid to the drug leakage from the vesicles during long-term storage. The application of optional ingredients to improve the stability and/or elasticity of the elastic liposomes is becoming a new trend.  相似文献   
14.
Exposure of fragrance ingredients in cosmetics and personal care products to the population can be determined by way of a detailed and robust survey. The frequency and combinations of products used at specific times during the day will allow the estimation of aggregate exposure for an individual consumer, and to the sample population. In the present study, habits and practices of personal care and cosmetic products have been obtained from market research data for 36,446 subjects across European countries and the United States in order to determine the exposure to fragrance ingredients. Each subject logged their product uses, time of day and body application sites in an online diary for seven consecutive days. The survey data did not contain information on the amount of product used per occasion or body measurements, such as weight and skin surface area. Nevertheless, this was found from the literature where the likely amount of product used per occasion or body measurement could be probabilistically chosen from distributions of data based on subject demographics. The daily aggregate applied consumer product exposure was estimated based on each subject’s frequency of product use, and Monte Carlo simulations of their likely product amount per use and body measurements. Statistical analyses of the habits and practices and consumer product exposure are presented, which show the robustness of the data and the ability to estimate aggregate consumer product exposure. Consequently, the data and modelling methods presented show potential as a means of performing ingredient safety assessments for personal care and cosmetics products.  相似文献   
15.
Economically relevant pathogens, such as African swine fever virus (ASFV), have been shown to survive when experimentally inoculated in some feed ingredients under the environmental conditions in transoceanic transport models. However, these models did not characterize the likelihood of virus survival under various time and temperature processes that feed ingredients undergo before they are added to swine diets. Here, we developed a quantitative risk assessment model to estimate the probability that one or more corn or soybean meal ocean vessels (25,000 tonnes) contaminated with ASFV would be imported into the United States annually. This final probability estimate was conditionally based on five likelihoods: the probability of initial ASFV contamination (p0), ASFV inactivation during processing (p1) and transport (p2), recontamination (pR), and ASFV inactivation while awaiting customs clearance at United States entry (p3). The probability of ASFV inactivation was modelled using corn and soybean (extruded or solvent extracted) processing conditions (times and temperatures), D-values (time to reduce 90% or 1-log) estimated from studies of ASFV thermal inactivation in pork serum (p1), and survival in feed ingredients during transoceanic transport (p2 and p3). ‘What-if’ scenarios using deterministic values for p0 and pR (1%, 10%, 25%, 50%, 75%, and 100%) were used to explore their impact on risk. The model estimated complete inactivation of ASFV after extrusion or solvent extraction processes regardless of the initial ASFV contamination probability assumed. The value of recontamination (ranging from 1% to 75%) was highly influential on the risk of one ASFV-contaminated soybean meal vessel entering the United States. Median risk estimates ranged from 0.064% [0.006%–0.60%; 95% probability interval (PI)], assuming a pR of 1.0%, up to 4.67% (0.45%–36.50% 95% PI) assuming a pR of 75.0%. This means that at least one vessel with ASFV-contaminated soybean meal would be imported once every 1563–21 years, respectively. When all raw corn was assumed to be contaminated (p0 = 100%), and no recontamination was assumed to occur (pR = 0%), the median probability of one vessel with ASFV-contaminated corn entering the United States was 2.02% (0.28%–9.43% 95% PI) or once every 50 years. Values of recontamination between 1% and 75% did not substantially change the risk of corn. Days of transport, virus survival during transport (D-value), and number of vessels shipped were the parameters most influential for increased likelihood of a vessel with ASFV-contaminated soybean meal or corn entering the United States. The model helped to identify knowledge gaps that are most influential on output values and serves as a framework that could be updated and parameterized as new scientific information becomes available. We propose that the quantitative risk assessment model developed in this study can be used as a framework for estimating the risk of ASFV entry into the United States and other ASFV-free countries through other types of imported feed ingredients that may potentially become contaminated. Ultimately, this model can be used to develop risk mitigation strategies and critical control points for inactivating ASFV during feed ingredient processing, storage, and transport, and contribute to the design and implementation of biosecurity measures to prevent the introduction of ASFV into the United States and other ASFV-free countries.  相似文献   
16.
目的:对金玄痔科熏洗散及有效部位新制剂进行GC-MS分析,建立了有效部位新制剂的GC-MS指纹图谱。方法:采用GC-MS方法对金玄痔科熏洗散及有效部位新制剂中的主要组分进行分析,并确定指纹图谱中的特征指纹信息。结果:对10个批次的有效部位新制剂进行了测定,并得到了较为理想的包含特征信息的有效部位新制剂的GC-MS指纹图谱。结论:方法重复性好,所建立的指纹图谱为金玄痔科熏洗散有效部位新制剂的质量控制提供了有效手段。  相似文献   
17.
近年来,随着脑血管病的发病率不断升高,其相关病症已经严重的影响了患者的生活质量。研究发现丹参类制剂及丹参活性成分具有明显的改善脑循环作用,主要从改善脑部微循环、改善脑侧支循环以及促进侧支血管的新生3个方面归纳总结了丹参类制剂及丹参活性成分改善脑循环的药理作用及作用机制,旨在为丹参类制剂改善患者脑循环的应用提供理论依据。  相似文献   
18.
目的探究淹水胁迫对杭菊绿原酸合成途径中的关键酶香豆酰基喹酸酯3’-单加氧酶(C3’H)和莽草酸羟基肉桂酰基转移酶(HCT)基因的表达和活性成分的影响。方法使用实时荧光定量PCR(qRT-PCR)方法基于杭菊转录组数据库克隆HCT和C3’H基因各2个,其中C3’H酶的2个基因CmC3’H1、CmC3’H2,HCT酶的2个基因CmHCT1、CmHCT2,并进行生物信息学分析;同时在杭菊花芽分化期进行淹水胁迫,以β-actin为内参基因,使用qRT-PCR检测以上4个基因的相对表达量;然后使用HPLC法测定杭菊这4个基因的下游产物及其他指标成分含量。结果通过研究获得了4条基因的完整开放阅读框,并且预测其氨基酸序列的相对分子质量和理论等电点(pI),同时构建蛋白质三级结构模型。qRT-PCR结果显示在花芽分化期对杭菊进行持续3 d的淹水处理会导致以上4个基因在不同生长时期内的表达显著变化。HPLC结果显示淹水处理后的杭菊C3’H和HCT所催化形成的下游产物绿原酸含量显著高于对照组,同时发现其他2种指标成分木犀草苷和3,5-O-二咖啡酰基奎宁酸含量也显著高于对照组。结论杭菊在淹水胁迫下可以通过调节4种基因的表达来调控下游产物的合成,从而对淹水胁迫做出应答,而且花芽分化期进行淹水胁迫可以显著增强杭菊活性成分的积累。  相似文献   
19.
位恒超  刘雅敏  韩德恩  田萍  辛玉凤 《中草药》2019,50(17):4158-4163
目的建立用HPLC波长切换法同时测定大黄利胆片中10个活性成分没食子酸、5-羟甲基糠醛、柯里拉京、对羟基苯甲醛、鞣花酸、芦荟大黄素、大黄酸、大黄素、大黄酚、大黄素甲醚含量的方法,并结合统计学分析对其质量进行评价。方法采用PhenomenexKinetexC18色谱柱,柱温为30℃,以甲醇-0.15%磷酸水溶液为流动相梯度洗脱,体积流量为1m L/min,检测波长分别为265.0 nm(0~5.8 min,检测没食子酸)、283.9 nm(5.8~7 min,检测5-羟甲基糠醛)、222.2(7~18 min,检测柯里拉京、对羟基苯甲醛)、256.7 nm(18~74 min,检测鞣花酸、芦荟大黄素、大黄酸、大黄素、大黄酚、大黄素甲醚);用SPSS21软件对10批药中成分含量进行统计学分析。结果 10个成分在各自质量浓度范围内线性关系良好(r0.9980),平均加样回收率98.45%~100.12%,RSD为0.80%~2.51%;含量分别为没食子酸8.371~11.438mg/片、5-羟甲基糠醛0.046~0.087mg/片、柯里拉京0.721~2.094mg/片、对羟基苯甲醛0.034~0.065mg/片、鞣花酸1.736~1.996mg/片、芦荟大黄素0.337~0.440mg/片、大黄酸1.636~2.562mg/片、大黄素0.602~0.846mg/片、大黄酚0.388~0.566mg/片、大黄素甲醚0.621~0.781 mg/片;10批样品质量基本一致。结论该方法简单准确,可用于大黄利胆片的质量控制。  相似文献   
20.
The objectives of this study were to explore sodium dodecyl sulfate (SDS) and Soluplus on the crystallization inhibition and dissolution of felodipine (FLDP) extrudates by bottom-up and top-down approaches. FLDP extrudates with Soluplus and SDS were prepared by hot melt extrusion, and characterized by polarized light microscopy, differential scanning calorimetry, and fourier transform infrared spectroscopy. Results indicated that Soluplus inhibited FLDP crystallization, and the whole amorphous solid dispersions (ASDs) were binary FLDP-Soluplus (1:3) and ternary FLDP-Soluplus-SDS (1:2:0.15~0.3 and 1:3:0.2~0.4) extrudates. Internal SDS (5%-10%) decreased glass transition temperatures of FLDP-Soluplus-SDS ternary ASDs without presenting molecular interactions with FLDP or Soluplus. The enhanced dissolution rate of binary or ternary Soluplus-rich ASDs in the nonsink condition of 0.05% SDS was achieved. Bottom-up approach indicated that Soluplus was a much stronger crystal inhibitor to the supersaturated FLDP in solutions than SDS. Top-down approach demonstrated that SDS enhanced the dissolution of Soluplus-rich ASDs via wettability and complexation with Soluplus to accelerate the medium uptake and erosion kinetics of extrudates, but induced FLDP recrystallization and resulted in incomplete dissolution of FLDP-rich extrudates. In conclusion, top-down approach is a promising strategy to explore the mechanisms of ASDs' dissolution, and small amount of SDS enhances the dissolution rate of polymer-rich ASDs in the nonsink condition.  相似文献   
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