共查询到20条相似文献，搜索用时 62 毫秒
1.
徐今宁 《河北北方学院学报(医学版)》2008,25(5)
脂质体（Liposome）是磷脂和其它两亲性物质分散于水中,由一层或多层同心的脂质双分子膜包封而成的超微球状载体制剂。脂质体具有的双重特性-亲水性和疏水性,决定了脂质体可以较好的包裹亲水性物质和亲脂性物质。1979年首次报道了以脂质体包封药物用于经皮吸收的研究,大量研究表明脂质体能够包裹并携带亲水或亲油性药物进入体内;可以包封难以透皮的药物及易受胃肠道破坏的生化高分子药物及疫苗,促进其透皮吸收,产生全身治疗作用及免疫预防效果;与皮肤角质层脂质有高度的生物相容性,能增加药物在皮肤局部的积累,起到持续的药物释放作用; 相似文献
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张兵锋陶守松易文奇徐忠荣 《宜春学院学报》2017,(12):30-31
采用安全性高的溶剂如丙二醇和聚乙二醇以及研磨法这一制备方法,先制成前体脂质体,再水合形成脂质体,即得新型氯尼达明脂质体。制得的氯尼达明脂质体粒径约160 nm,并且较为均一;采用反透析法测得包封率为86.12%;体外释放结果显示具有一定的缓释性。本研究中制备氯尼达明脂质体的制备工艺相对简便,有利于工业生产,且包封率及稳定性较好,将能较好地提高氯尼达明的生物利用度。 相似文献
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用聚乙二醇(PEG)包覆脂质体来提高脂质体的稳定性．先用反相蒸发法制备醋酸泼尼松龙脂质体,然后将PEG溶液与醋酸泼尼松龙脂质体混合即可制得PEG包覆的脂质体,原子力扫描探针显微镜照片与粒径证明PEG在脂质体外形成了一层膜,相比较于未包覆的脂质体,PEG包覆的脂质体的包封率和粒径都有所增加,泄漏率降低,其泄漏率随时间和温度的增加而增加,但低于未包覆的脂质体．通过测定粒径和泄漏率的变化说明包覆PEG的脂质体要比未包覆的稳定． 相似文献
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《嘉应学院学报》2016,(5):57-62
目的:制备脑靶向紫杉醇脂质体,并对其制备工艺进行优化.方法:以包封率为评价指标,筛选该脑靶向紫杉醇脂质体的最佳制备方法,选取药脂比、膜材比、水化温度和水化时间为因素,采用正交设计优化该脂质体的制备工艺.结果:脑靶向紫杉醇脂质体最佳制备方法为薄膜分散法,该方法的最优处方组成为:药脂比为0.1,膜材比为0.5,水化时间0.5 h,水化温度40℃,平均包封率为:(91.05±1.85)%(n=4),粒径:(106.14±1.30)nm(n=4),多分散系数(PDI):(0.195±0.005)(n=4),平均Zeta电位:(-23.9±0.42)m V(n=4).结论:用薄膜分散法制备的脑靶向紫杉醇脂质体包封率高,粒度小且均匀,稳定性良好,为其药代动力学和药理学研究奠定基础. 相似文献
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《实验室研究与探索》2017,(6):18-20
通过对脂质体内外水相pH梯度的制备方法的探讨,采用凝胶过滤层析技术将脂质体外水相的pH4.0柠檬酸缓冲液替换成pH 7.2磷酸盐缓冲液,在脂质体内外水相形成pH梯度。在药脂比为1∶5、1∶10、1∶15和1∶20(质量比)时,阿霉素在pH梯度的驱动下从脂质体外水相穿越脂质双分子膜进入内水相,包封率分别达到96.7%、98.7%、96.8%和95.1%,其中药脂比1∶10时包封率达到最高。药脂比1∶10制备的阿霉素脂质体在37℃,12 h内阿霉素泄漏均低于1.0%;48 h内药物泄露率低于5.0%。通过该实验,使学生们能够观测到如何采用凝胶过滤层析技术调节pH梯度,以及pH梯度在阿霉素脂质体主动载药过程中的重要性,为脂质体递释系统的课堂理论教学奠定了良好的实验基础。 相似文献
6.
胸腺肽聚乳酸微球的制备和体外释药研究 总被引：4，自引：0，他引：4
为了寻找适于多肽分子吸收,免疫学上"有效"、"安全",且服用方便的口服制剂,用W/O/W型乳化挥发法制备胸腺肽聚乳酸微球,正交实验方法优化了制备工艺.通过差热分析证明载药微球已较好形成,Lowry法测定药物的含量,计算微球的载药量、包封率及体外释药量.结果表明,所得微球平均粒径为13.8 μm,平均包封率为80.7%,前12 h的体外释药符合Higuchi方程,T1/2=295 min,在25℃和40℃分别放置90d,微球的粒径分布和剩余药量无显著变化.微球的载药量和包封率符合要求,释药半衰期长,具有良好的应用前景. 相似文献
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本实验以经过青霉素筛选后的两株絮凝菌为对象,分别测定其溶菌酶处理前总菌数、溶菌酶处理后总菌数和原生质体再生菌数,计算原生质体形成率和再生率,并对PEG的作用浓度和时间进行优化。实验结果：F2原生质体形成率为99.97%,F6原生质体形成率为99.96%,F2原生质体再生率为0.4225%,F6原生质体再生率为0.5423%,初步判断溶菌酶处理后得到的原生质体在质量和数量上满足细胞融合需求,确定了原生质体融合PEG最佳作用浓度为30%,最佳作用时间为10 min,以保证原生质体融合的完成。 相似文献
8.
氯氰碘柳胺脂质体的研制和驱虫效果试验 总被引：3，自引：0，他引：3
采用改良的冷冻融溶法制备氯氰碘柳胺脂质体，经线性试验、方法回收率、包封率测定和稳定性试验，该制剂符合质量标准。临床药物试验表明以2.5mg/kg的剂量皮下注射，对绵羊的肝片吸虫有完全的驱除作用，最佳使用剂量。该制剂用药量小，疗效高，毒副作用低，是一种值得推广的抗寄生虫药物。 相似文献
9.
氯氰碘柳胺脂质体的研制和驱虫效果试验 总被引：3，自引：0，他引：3
采用改良的冷冻融溶法制备氯氰碘柳胺脂质体，经线性试验、方法回收率、包封率测定和稳定性试验，该制剂符合质量标准。临床药物试验表明以2．5mg/kg的剂量皮下注射，对绵羊的肝片吸虫有完全的驱除作用，最佳使用剂量。该制剂用药量小，疗效高，毒副作用低，是一种值得推广的抗寄生虫药物。 相似文献
10.
张小琴 《阿坝师范高等专科学校学报》2013,(2):125-128
研究表明,由于脂质体具有靶向、长效、降低毒性及保护包封药物的优点,脂质体作为抗肿瘤抗癌药物载体已成为研究和应用的热点。近年来,脂质体的抗肿瘤中药得到了广泛的研究,取得了较大的进展。通过对脂质体在中草药生物碱、黄酮化合物、萜类化合物、多糖等抗肿瘤方面的作用的分析比较,希望为进一步研究脂质体在抗肿瘤中草药中的应用提供参考。 相似文献
11.
罗艳萍 《读与写:教育教学刊》2008,5(6)
The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity. 相似文献
12.
邱崇丙 《唐山师范学院学报》2014,(1):21-23
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。 相似文献
13.
Richard Denner 《海外英语》2007,(4):14-15
Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose. 相似文献
14.
Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F. 相似文献
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《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help? 相似文献
18.
陈美曦 《山东教育学院学报》2008,23(2):103-107
Different nations have different social cultures, and the social culture of every nation is developing with the development of the nation, language is greatly influenced by social culture, which enables language to possess national and historical characteristics. Word is the smallest, independent, meaningful linguistic unit of language. It can well reflect the national and historical characteristics. From synchronic aspect, the social and cultural influence on word meaning is mainly embodied in conceptual and associative meanings of word. The incorrespondence of word meaning is a phenomenon that exists in both conceptual and associative meanings of word among different languages. From diachronic aspect, the development of social culture causes some changes of word meaning to some extent. Therefore, social culture plays a key role in vocabulary learning and mastery of a language. 相似文献
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Rachel Zupek 《海外英语》2007,(11):40-41
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了 相似文献
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YANGShiguo 《重庆大学学报(英文版)》2004,3(1):86-88
The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex. 相似文献