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纳米载体在改善中药有效成分溶解性、生物膜透过性与生物体内行为、增效减毒等方面发挥着重要作用,具有广阔的应用前景。作为新型纳米载体,有机-无机杂化纳米载体由有机和无机材料或载体复合而形成,结合了两者的优势,能够更好地发挥其在药物递送中的作用,提高药物稳定性、载药量和生物相容性,并可以实现多功能化。笔者对近年来国内外中药有效成分有机-无机杂化纳米载体的研究和应用情况进行了总结与分析,并展望其发展前景,可为高效安全递送中药有效成分的新型递药系统的研究提供参考。 相似文献
3.
《Yao wu shi pin fen xi = Journal of food and drug analysis.》2019,27(4):869-875
In the present study, the influences of diets (i.e. chow and AIN-93 diets) on the interpretation of various fecal parameters including viable microbiota, moisture, weight, and short-chain fatty acids in rats fed different amounts of inulin (0.5–2 g/kg). Eight groups of rats (n = 8/group) were fed, for 4 weeks, chow or AIN-93 diets with or without inulin supplementation. Fecal samples were analyzed for different fecal parameters. After a 2-week adaptation, apparent differences in some fecal parameters were observed between the chow and AIN-93 diet groups. Throughout the 4-week intervention period, significantly (p < 0.05) higher Lactobacillus spp. counts, fecal moisture (∼2.7-fold), and fecal weight (∼5.8-fold) were observed with chow diet over AIN-93 diet. More specifically, significant elevations in the levels of Bifidobacterium spp., Lactobacillus spp., fecal moisture, and fecal weight could be observed at low-dose (0.5 g/kg) of inulin in chow diet groups, while most of these changes could merely be seen at medium-dose (1 g/kg) in AIN-93 diet groups. These results demonstrated that the choice of experimental diets would affect the comparison of fecal parameters as well as the interpretation of effective dosage of prebiotic in intestinal health assessments. 相似文献
4.
目的研究47份不同来源、不同表型正品细辛样品的有效成分含量,评价正品细辛样品的质量,揭示有效成分形成与遗传和地域的关系,为细辛优良品种选育与开发利用提供理论依据。方法冷凝回流法提取挥发油、乙醇热浸法提取醇溶性浸出物,HPLC法测定细辛脂素含量、气质联用(GC-MS)分析挥发油组分,组间联接法进行聚类分析。结果 47份细辛样品挥发油量0.81%~3.32%。有5份样品挥发油量超过3.0%。醇溶性浸出物量为9.87%~29.40%,含量超过20%的样品占总数的63.8%。细辛脂素质量分数为0.118%~0.424%,有26份样品细辛脂素质量分数超过0.25%;47份细辛挥发油可分离出的化合物种类48~77种,化合物种类和含量有较大差异。基于有效成分的聚类分析将不同来源地、不同表型的细辛分为10类,聚类方式基本是按照来源地为基础进行聚类,同一来源地的汉城细辛和北细辛聚在一类中。结论在同一栽培环境和条件下,不同来源地、不同植物学表型的样品个体间有效成分含量间存在差异,新品种选育时可依照植物表型选择优良育种材料。大部分样品聚类与来源地域有关而与植物表型以及植物学分类无关。 相似文献
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目的:分析重庆地区化妆品变应性接触性皮炎患者主要化妆品成分变应原,以便指导患者合理选择和使用化妆品,降低皮炎的发生率。方法:选取我院皮肤科门诊确诊为化妆品变应性接触性皮炎的193例患者进行化妆品成分斑贴试验,并对结果作统计学分析。结果:斑贴试验总阳性率为69.43%,合并2种及2种以上变应原的患者占50.26%,阳性率前5位的变应原分别为硫柳汞、十二烷基硫酸钠、尼泊金酯、三乙醇胺和乙二胺;女性斑贴试验阳性率为73.33%,明显高于男性,差异有统计学意义(X2=9.67,P<0.05);青年组明显高于其他年龄组,差异有统计学意义( X2=36.79,P<0.05)。结论:硫柳汞、十二烷基硫酸钠、尼泊金酯、三乙醇胺和乙二胺5种物质是重庆地区化妆品变应性接触性皮炎患者主要的致敏成分。化妆品变应性接触性皮炎患者以女性为主,中青年多见。 相似文献
7.
Rachel A. Schambow Fernando Sampedro Pedro E. Urriola Jennifer L. G. van de Ligt Andres Perez Gerald C. Shurson 《Transboundary and Emerging Diseases》2022,69(1):157-175
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
8.
《Regulatory toxicology and pharmacology : RTP》2015,73(3):660-672
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
9.
切胶免疫制备腮腺液高丰度蛋白多克隆抗体 总被引:2,自引:0,他引:2
目的 通过切胶免疫制备人腮腺液高丰度蛋白多克隆抗体,为下一步腮腺液高丰度蛋白单克隆抗体制备提供抗原解决方案.方法 将腮腺液经超滤法浓缩蛋白后,进行SDS-PAGE分析,切取分子量约为50-65kDa的高丰度蛋白条带,研磨后注射新西兰大耳白兔诱导产生免疫应答并制备兔抗人腮腺液高丰度蛋白多克隆抗体,并应用蛋白免疫印记(Western blot)等方法进行抗体鉴定.结果 成功制备和鉴定了人腮腺液高丰度蛋白多克隆抗体.结论 成功制备和鉴定了人腮腺液高丰度蛋白多克隆抗体,为下一步腮腺液高丰度蛋白单克隆抗体制备及唾液蛋白质组学研究奠定基础. 相似文献
10.
Kanda M Inoue H Fukuizumi T Tsujisawa T Tominaga K Fukuda J 《Oral microbiology and immunology》2001,16(5):257-264
In rabbits, Staphylococcus lentus is one of the major bacteria in saliva and a minor bacteria in jejunum fluids and nasal wash. The presence and induction of naturally occurring antibodies reacting to rabbit indigenous bacteria were studied. In non-immune rabbits, the proportion of anti-S. lentus IgA antibodies to total IgA in the saliva was several times higher than that in the intestinal fluids and the nasal wash. The salivary antibodies were found to have increased 1 week after a single tonsillar application of isolated S. lentus cells but not after a single nasal application or a single intragastric instillation. In addition, the anti-S. lentus antibodies in the saliva highly increased with weekly tonsillar applications of isolated S. lentus but increased only one-fifth with weekly nasal applications of the same cells. These results strongly suggest that the palatine tonsils, which we believe had already been sensitized by S. lentus in the physiological condition, induced naturally occurring antibodies in rabbit saliva. 相似文献