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1.
This study deals with the formulation of natural drugs into hydrogels. For the first time, compounds from the sage essential oil were formulated into chitosan hydrogels. A sample preparation procedure for hydrophobic volatile analytes present in a hydrophilic water matrix along with an analytical method based on the gas chromatography coupled with the mass spectrometry (GC-MS) was developed and applied for the evaluation of the identity and quantity of essential oil components in the hydrogels and saline samples. The experimental results revealed that the chitosan hydrogels are suitable for the formulation of sage essential oil. The monoterpene release can be effectively controlled by both chitosan and caffeine concentration in the hydrogels. Permeation experiment, based on a hydrogel with the optimized composition [3.5% (w/w) sage essential oil, 2.0% (w/w) caffeine, 2.5% (w/w) chitosan and 0.1% (w/w) Tween-80] in donor compartment, saline solution in acceptor compartment, and semi-permeable cellophane membrane, demonstrated the useful permeation selectivity. Here, (according to lipophilicity) an enhanced permeation of the bicyclic monoterpenes with antiflogistic and antiseptic properties (eucalyptol, camphor and borneol) and, at the same time, suppressed permeation of toxic thujone (not exceeding its permitted applicable concentration) was observed. These properties highlight the pharmaceutical importance of the developed chitosan hydrogel formulating sage essential oil in the dermal applications.  相似文献   
2.
神话对中国和希腊两国文学皆产生了巨大影响。但由于中希两国地域、自然条件、文化传统及民族个性等各方面的不同,使得两国的古代神话呈现出不同的艺术风貌。希腊神话体现的是个性、力量和人性,中国的神话则崇尚共性、德行和神性。本文将从这三方面简要探讨中国神话和希腊神话之间的差异,以便更深刻地了解中希两国文化。  相似文献   
3.
论希腊神话中的复仇母题   总被引:1,自引:0,他引:1  
复仇是人类社会实践历程中都盛行过的一种特殊的历史文化现象,复仇母题在希腊神话中得到了最丰富而生动的体现。我们根据复仇行为的动机、复仇主体和其中所表现的法律伦理价值,可以将希腊神话中的复仇母题归纳为血亲复仇、荣誉复仇、情爱复仇这三类形态。  相似文献   
4.
5.
The effect of relative humidity (RH) and light conditions on the oxidative stability of sunflower oil (SO) stabilised with oleoresin rosemary + ascorbyl palmitate (SOR), sage + ascorbyl palmitate (SOS) and tertiary butyl hydroquinone (SOT) was investigated. The SO without additive (SOC) served as positive control. Oil samples were subjected to 3 RH (29%, 52% and 75%) and two light conditions (dark, D and fluorescent light (600 lx), L) at 60 °C for 7 days. The oxidative stability was monitored by peroxide value (PV), conjugated diene value (CDV), free fatty acids (FFAs) and Rancimat induction period (IP). A direct relationship was noted between RH and increase in PV, CDV and FFA levels irrespective of light conditions. The detrimental effect of light on the oxidative stability was prominently noted at higher RH (75%) which followed an order: SOC > SOT > SOR > SOS. The samples stored under lower RH (29% and 52%), and dark conditions were better stabilised than light‐exposed counterparts.  相似文献   
6.
The aim of this study was to improve textural and antioxidant capacity of dromedary yogurt using ultrafiltration process and date powder. Ultrafiltration increased total solids content of dromedary milk within the range considered optimal to develop yogurt. Texture profile of Greek yogurt fortified with date powder (GYD) improved considerably compared to control. Sample of GYD are more appealing to consumer than control. LC-ESI-MS analysis of GYD extracts allowed the identification of fifteen phenolic compounds, among which quinic acid and cirsiliol were found to be the major phenolic acid and flavonol, respectively. GYD exhibited the highest DPPH•-radical scavenging activity, Fe2+ chelating capacity and Fe3+ reducing power. The follow-up of physical and microbiological stability of GYD and control during cold storage showed that date powder significantly increased bacterial counts and decreased syneresis. Therefore, ultrafiltration and date powder could be valued as effective tool to solve the poor consistency of dromedary milk products.  相似文献   
7.
A survey of the information contained in the labels of 109 commercial concentrated fermented milks from the Eastern Mediterranean, Australasia, the United Kingdom, Ireland, the United States of America and Canada plus Skyr (from Iceland), Ymer (from Denmark) and Chakka (from India) was carried out in late 2012 and early 2013. There were substantial differences in composition. The carbohydrate, fat and protein contents ranged between 1–12, 0–20 and 3.3–11 g/100 g, respectively. Considering the compositional data of the product and existing legislative provisions, a typical strained product should have a protein content of ≥8 g/100 and ~5 g/100 g of carbohydrates, and it would be appropriate to name such products as ‘strained yoghurt’, ‘Greek strained yoghurt’ and/or ‘Labneh’. A higher content of carbohydrate would suggest that the product was made using the product formulation method (i.e. without straining the fermentate), or the milk base had been fortified with skimmed milk before straining the fermentate to enhance the yield of the product, and such products should be known, for example, as ‘Greek‐style yoghurt’. It was also observed in some of the samples that the nomenclature of the starter cultures did not conform to recommendations of the International Union of Microbiological Societies (IUMS). Manufacturers could address such issues to minimise consumer confusion.  相似文献   
8.
从香紫苏油中分离提纯芳樟醇和乙酸芳樟酯工艺的研究   总被引:1,自引:0,他引:1  
采用真空间歇精馏技术,通过变换操作工艺条件,对香紫苏油进行分离得到芳樟醇和乙酸芳樟酯产品.考虑原料的热敏性制定出适宜的分离方案:首先在操作压力为1.5kPa条件下对原料进行初步分离,得到富含芳樟醇的轻馏分和富含乙酸芳樟酯的重馏分两个原料;再分别对轻馏分和重馏分进行不同条件下的真空间歇精馏,可以使芳樟醇的含量达到90.6%,乙酸芳樟酯的含量达到96.6%,满足两产品的不同需求.在提纯轻馏分中芳樟醇时,操作压力为5kPa,塔釜温度小于105℃;在提纯重馏分中乙酸芳樟酯时,操作系统压力为1.33kPa,塔釜温度低于110℃.此分离操作工艺,缩短了乙酸芳樟酯的受热时间、降低了分离温度以及乙酸芳樟酯因受热而异构化的趋势,降低了能耗.  相似文献   
9.
在中国现代戏剧发展史上,曹禺是西方戏剧营养的最大受益者。这其中,希腊悲剧的影响尤其深刻。本文通过《雷雨》与最能代表古希腊悲剧特征的《俄狄浦斯王》的比较,试图从遗传与继承的角度,对《雷雨》中所“流淌”的古希腊悲剧血统做另类探究。  相似文献   
10.
This study used latent growth curve modeling to investigate whether the effects of gender and Greek involvement on alcohol use and problems over the first 2 years of college are best characterized by selection, socialization, or reciprocal influence processes. Three social influences (alcohol offers, social modeling, and perceived norms) were examined as potential mediators of these effects. Undergraduate participants (N = 388) completed self-report measures prior to enrollment and in the spring of their freshmen and sophomore years. Male gender and involvement in the Greek system were associated with greater alcohol use and problems prior to college. Both gender and Greek involvement significantly predicted increases in alcohol use and problems over the first 2 years of college. Cross-domain analyses provided strong support for a mediational role of each of the social influence constructs on alcohol use and problems prior to matriculation, and prematriculation social modeling and alcohol offers mediated relations between Greek involvement and changes in alcohol use over time. Findings suggest that students, particularly men, who affiliate with Greek organizations constitute an at-risk group prior to entering college, suggesting the need for selected interventions with this population, which should take place before or during the pledging process. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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