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1.
微乳对难溶性药物增溶机理的研究   总被引:17,自引:1,他引:16  
目的:初步探讨微乳对难溶性药物的增溶机理.方法:经处方筛选及相图研究确定(BL-9/正丁醇3∶1)/油/水比例为9∶1∶40的微乳处方;以二氢吡啶类药物为模型药物,测定其在微乳、胶束和油相中的溶解度及油/水分配系数;根据化学结构,采用计算机软件计算药物的特性参数,并结合模型药物的特性分析微乳增溶难溶性药物的机理.结果:微乳对药物的增溶效果远大于油相和胶束,并随药物的脂溶性和空间结构的改变而变化.结论:微乳可用于增溶难溶性药物,且脂溶性越大,空间位阻越小,增溶效果越明显.  相似文献   
2.
There is a growing need for research into new skin- and environment-friendly surfactants. This paper focuses on a natural surfactant of an alkylpolyglucoside type, which can form both thermotropic and lyotropic liquid-crystalline phases. The aim of this study was to relate some physicochemical properties (characterised by polarisation and transmission electron microscopy, thermal analysis and rheology) of the three formulations based on cetearyl glucoside and cetearyl alcohol, to the results of in vitro and in vivo bioavailability of hydrocortisone (HC). The three formulations contained oils of different polarity (medium chain triglycerides: MG, isopropyl myristate: IPM and light liquid paraffin: LP), respectively. In vitro permeation was followed through the artificial skin constructs (ASC), while the parameters measured in vivo were erythema index: EI (using instrumental human skin blanching assay), transepidermal water loss (TEWL) and stratum corneum hydration (SCH). The vehicles based on cetearyl glucoside and cetearyl alcohol showed a complex colloidal structure of lamellar liquid-crystalline and lamellar gel-crystalline type, depending on oil polarity. Rheological profile of the vehicle was directly related to the in vitro profile of the HC permeation. In vivo results suggested that the vehicle with MG retarded the HC permeation, whereas less polar IPM and non-polar LP enhanced it. It is suggested that the enhancement is achieved either by a direct interaction with lipid lamellae of the SC or indirectly by improving skin hydration.

There were no adverse effects during in vivo study, which indicates a good safety profile of this alkylpolyglucoside surfactant.  相似文献   

3.
The effects of linoleic acid, linoleic acid anilide, and arachidonic acid on the expression of CD11b/CD18, CD11c/CD18 integrins and l-selectin on human neutrophils were studied by flow cytometry in a whole blood assay. None of these compounds had any effect on the basal expression of CD11b, CD11c, or l-selectin in the concentration range of 20–100 μM. However, linoleic acid at a concentration of 1000 μM slightly up-regulated CD11b and CD11c by a factor of 2.1 and 1.7, respectively. Linoleic acid, linoleic acid anilide, and arachidonic acid did not affect the formyl-methionyl-leucyl-phenylalanine induced up-regulation of CD11b or CD11c. However, linoleic acid and linoleic acid anilide slightly inhibited the phorbol myristate acetate (PMA)-induced expression of CD11b, which was decreased by 27 and 21% at concentrations of 100 and 1000 μM, respectively. Likewise, arachidonic acid at 40 μM inhibited the PMA-induced expression of CD11b by 19%. Our results suggest that linoleic acid, linoleic acid anilide, and arachidonic acid do not dramatically affect the expression of leukocyte adhesion molecules in a whole blood assay. Received: 17 February 1997  / Accepted: 5 May 1997  相似文献   
4.
超临界CO2萃取薏苡仁油工艺条件优化   总被引:5,自引:0,他引:5       下载免费PDF全文
目的应用超临界CO2萃取技术提取薏苡仁中的薏苡仁油,优化工艺条件。方法利用1L与600L的超临界萃取装置,考察原料水份、压力、时间与温度等参数对薏苡仁油提取得率的影响。结果优化得到用超临界CO2萃取技术从薏苡仁中提取薏苡仁油的工艺参数。结论超临界CO2萃取技术可用于薏苡仁油的提取,适用于工业化生产。  相似文献   
5.
目的 探讨维生素E油浴应用于早产儿治疗中的作用。方法 对2001年3月~2003年12月我院住院的42例患肺透明膜病的早产儿,28例患新生儿硬肿症的早产儿及随机抽取的50例早产儿,三种情况早产儿分别随机分为治疗组和对照组,对照组给予常规治疗,治疗组在常规治疗的基础上加用维生素E油浴。结果 治疗组治疗的时间均短于对照组(P〈0.05)。结论 维生素E油浴在早产儿治疗中有促进疾病好转和恢复的作用,并且未发现维生素E油浴的不良反应。  相似文献   
6.
Genetic trace metal disturbances can be at three levels. Trace metals play an important role in the metabolism of genetic macromolecules and the information transfer system. Deficiency or excess of trace metals caused either by dietary or genetic factors will affect the normal functioning of the whole organism. The roles of trace metals in carcinogenesis/mutagenesis and ageing are typical of this category. The second level of genetic trace metal disturbances affect the metabolic pathway of the trace metal itself. Biochemical derangement resulting from genetic defects cause aberrant metabolism of the element and thus disease symptoms. Diseases caused by abnormal metabolism of copper, zinc, iron, and molybdenum are discussed. Trace metal disturbances can also be the result of other genetic diseases. This aspect of genetic trace metal disturbances is least investigated. However, information should be important for improving the existing treatment protocol for the more common inborn errors of metabolism, such as phenylketonuria.  相似文献   
7.
8.
AimTo critically appraise and evaluate the evidence from randomized clinical trials (RCTs) examining the effectiveness of oil pulling on oro dental hygiene.MethodsWe conducted electronic searches in Medline, Embase, Amed, The Cochrane Library and Cinahl databases from inception to February 2015, and assessed reporting quality using the Cochrane risk of bias criteria. We included RCTs that compared oil pulling using conventional cooking oils with a control intervention. Our primary outcomes were measures of oro dental hygiene using validated scales.ResultsElectronic searches yielded 26 eligible studies, of which five RCTs comprising a total of 160 participants were included. The studies varied in reporting quality, lasted between 10 and 45 days, and compared oil pulling with chlorhexidine, placebo or routine dental hygiene practice. Three studies reported no significant differences in post intervention plaque index scores between oil pulling and control groups (Chlorhexidine mouthwash +/− Placebo): p = 0.28, 0.94, and 0.38, respectively. Two studies reported no significant difference in post-intervention modified gingival index score between oil pulling and Chlorhexidine mouthwash groups (p = 0.32 and 0.64).ConclusionThe limited evidence to date from clinical trials suggests that oil pulling may have beneficial effects on oro dental hygiene as seen for the short period of time investigated. Given that this is a potentially cost-effective intervention, this practice might be of particular benefit. Future clinical trials should be more rigorous and better reported.  相似文献   
9.
目的:揭示大果木姜子油治疗心力衰竭的作用机制。方法:首先从动物药理学实验验证疗效,采用异丙肾上腺素(ISO)诱导复制心力衰竭大鼠模型,造模成功后应用大果木姜子油治疗4周,监测血流动力学指标,分析血清BNP水平和心肌组织形态学变化;然后基于文献检索和TCMSP数据库获取大果木姜子油活性成分及作用靶点,从CTD和Drugbank数据库筛选心力衰竭的已知治疗靶点,将疾病治疗靶点与大果木姜子油活性成分作用靶点进行Venn分析,运用SYBYL软件进行分子对接验证,运用STRING数据库分析蛋白互作关系,再利用DAVID数据库进行GO分子功能和KEGG通路富集分析。结果:大果木姜子油可显著升高ISO诱导的心衰大鼠LVSP、±dp/dtmax,降低LVEDP和BNP水平,改善心肌组织形态学变化;获得大果木姜子油20个活性成分,其中7个活性成分(沉香螺旋醇、芳樟醇、萜品烯-4-醇等)可能通过调控一个蛋白互作网络治疗心力衰竭,该网络中的靶点有PTGS1、PTGS2、NOS2、NOS3、GSK3B;由蛋白富集分析发现,这些靶点与前列腺素内过氧化物合酶活性和一氧化氮合酶活性有关。结论:大果木姜子油可改善心衰大鼠的血流动力学紊乱及心肌组织形态学变化;其治疗心力衰竭的机制可能与调控前列腺素内过氧化物合酶活性和一氧化氮合酶活性有关。  相似文献   
10.
刘雪  崔颖  黄顺旺  王浩  陈师农  孙备  吕凌 《安徽医药》2015,19(11):2065-2068
目的 建立清热解肌颗粒中挥发油成分的质量标准.方法 采用薄层色谱法(TLC)对清热解肌颗粒中挥发油进行定性鉴别;采用气—质联用色谱仪(GC-MS)对挥发油提取物的成分进行鉴定;采用气相色谱法(GC)测定制剂中挥发油的含量.结果 薄层色谱斑点清晰,重现性好,阴性对照无干扰.GC-MS共检出13个色谱峰并鉴定出12个化合物.α-蒎烯、β-蒎烯、桉油精线性范围分别为1.89~605.00mg·L-1(r=1.000),1.25 ~99.60mg· L-1(r=1.000),2.32 ~185.81 mg·L-1(r=1.000),平均加样回收率分别为92.82%(RSD =4.83%)、94.29%(RSD=3.10%)和104.23% (RSD =3.14%) (n =9).结论 所建立的方法准确、可靠、专属性强,可用于该制剂的质量控制.  相似文献   
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