共查询到20条相似文献，搜索用时 890 毫秒
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目的:采用高效薄层色谱扫描法(HTLCS)同时测定滁菊中木犀草素、芹菜素和金合欢素的含量。方法:采用硅胶GF254高效薄层板条带点样,以甲苯∶乙酸乙酯∶甲酸∶水=17∶7∶3∶2上层溶液为展开剂,上行展开,于365nm波长下进行直线扫描,测定滁菊中的木犀草素、芹菜素、金合欢素的含量。结果:分别在0.066 1～0.335 2μg(r=0.999 9),0.068 4～0.333 8μg(r=0.997 9)、0.064 0～0.334 2μg(r=0.995 2)范围内,木犀草素、芹菜素、金合欢素线性关系良好;平均回收率分别为99.9%、100.65%、101.3%,RSD分别为1.55%、1.41%、1.64%。结论:以HTLCS为质量控制方法,建立了一种简便、快速、准确的药物检测方法。 相似文献
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蛇床子素注射液的制备及稳定性考察 总被引：1，自引：0，他引：1
目的：探讨蛇床子素注射液的处方及制备工艺并考察其稳定性。方法：采用紫外分光光度计测定注射液的含量，用初匀速法考察制剂在室温25℃下的贮存期和对强光的稳定性。结果：蛇床子素注射液对光稳定性较差，在25℃下蛇床子素注射液贮存期为1．98年。结论：本品制备方便．工艺可行，稳定性试验符合Arrhenius指数规律。 相似文献
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建立复方蛇床予搽剂中蛇床子素和醋酸地塞米松含量的RIP-HPLC测定法.方法:色谱条件为色谱柱:Sino Chrom ODS-BP(4.6mm× 250mm,5pm);检测波长240nm;柱沮35℃;流动相:甲醇-水(7S:2S);进样:20μl(样品用乙醇稀释8倍):流速:0.8ml·min-1;分析时间:30min.结果:回归方程与相关性;蛇床子素(进样范嘲2.608～13.04μg,Y =850574.6X+120226A,r=0.9992,);醋酸地塞米松(进样范围0.1808～1.4464μg,Y=1748870X+249657,r=9996).加样回收率(n=3):蛇床子素98.65%,醋酸地塞米松98.0%.建立的方法用于供试制剂中蛇床子素和醋酸地塞米松的测定,简单,快速,准确,可行. 相似文献
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目的:通过不同实验方法,对湖北、安徽、浙江、山东四种产地蛇床子药材,进行品种和质量的实验分析,确定品质较优的蛇床子产地.方法:将四种产地蛇床子药材用95％乙醇回流提取,再经浓缩、离心、吸附获得供试品.以蛇床子中总香豆素为研究指标,采用性状分析、紫外分光光度法和薄层分析法测定四种产地蛇床子的总香豆素含量,综合分析进行比较.结果:紫外分光光度法测得山东、湖北、浙江、安徽四个产地的蛇床子,同一水平下的提取物在标准曲线上对应的浓度分别是0.1033 mg/mL、0.0181 mg/mL、0.0976 mg/mL、0.1096 mg/mL.薄层分析与标准品的对照显示中,四种产地的蛇床子以安徽的荧光点最大,山东次之,浙江产地的荧光点比湖北产地明显.结论:以香豆素为指标,四个产地中蛇床子的质量优质顺序为安徽＞山东＞浙江＞湖北. 相似文献
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目的：建立测定独活中蛇床子素和异欧前胡素的高效液相色谱法．方法：采用ZorbaxC18柱,乙腈-0．1％三乙胺水溶液（75：25）为流动相,流速为1mL·min^-1,检测波长308nm．结果：蛇床子素的线性范围为25．6～186．8mg·L^-1,回归方程为Y=4．352×10^4X＋1．062×10^2,r=0．9998,平均加样回收率为98．2％,RSD=1．02％;异欧前胡素的线性范围为1．66～20．4mg·mL^-1,回归方程为Y=5．736X10^2X＋1．122,r=0．9999,平均加样回收率为98．8％,RSD=1．04％．结论：该方法简便、快速、准确,适用于独活中蛇床子素和异欧前胡素的质量控制． 相似文献
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从太白山野生长春七的果实中首次分离得到蛇床子素,对其分子构型和晶体结构进行分析.方法:以95%乙醇提取野生的长春七果实,经柱色谱分离,在95%乙醇中重结晶得到针状晶体;用核磁共振波谱和X-单晶衍射进行蛇床子素的分子构型和晶体结构分析.结果:在蛇床子素分子中,香豆素核构成一个平面,3-甲基-2-丁烯基构成另外一个平面,它们间的二面角为74.45°.蛇床子素晶体结构属三斜晶系(P-1),a=7.5025(17)A,b=9.651(2)A,c=10.736(2)A,a=64.393(4)°.,B=75.716(4)°,Υ=71.679(4)°,Z=2.结论:确定了蛇床子素的分子构型和晶体结构. 相似文献
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目的：研究蛇床子素（osthol,Ost）在大鼠体内的组织分布特征,为临床合理用药提供合理依据。方法：大鼠腹腔注射（intraperitoneal injection,ip）30,120 mg·kg-1蛇床子素后,采用RP-HPLC法测定大鼠组织中不同时间点的药物浓度,分析蛇床子素在大鼠体内的组织分布特点。结果：大鼠腹腔注射蛇床子素后,组织分布较快,给药5 min 8种组织中均可检测到蛇床子素,10 min内心、肝、肺、肾均可达到峰值。当给药浓度增加4倍时,蛇床子素在各组织中的达峰时间没有显著性变化,只是相应时间点的药物浓度均略有升高,药物消除的时间也相应延长。结论：蛇床子素在大鼠组织中分布快、广泛,消除也快,且可能穿越血脑屏障和血睾屏障。 相似文献
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以乙醚为改性剂,采用超临界CO2萃取法提取中药蛇床子的有效成分,并用GC／MS法对其化学成分和相对含量进行了分析．结果表明,与水蒸气蒸馏法比较,超临界CO2萃取法的产率较高,总萃取率为8．46％(w),蒸馏法提取蛇床子挥发油的产率较低,仅为1．01％(w);蛇床子超临界萃取物中香豆素类的相对含量约为67．63％,其蛇床子素相对含量占总香豆素的78．92％,而蒸馏法提取的挥发油中鉴定出一种香豆素成分,其相对含量仅为1．65％．因此,超临界CO2萃取法可以有效提取中药蛇床子的多种香豆素类成分,其方法为其他同类中药的开发和药学鉴定提供了参考依据． 相似文献
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高效薄层双波长扫描法测定正青风痛宁片中青藤碱的含量 总被引：2，自引：0，他引：2
目的：为该药的质量控制和含量测定提供可靠的依据和方法。方法：在硅胶GF254高效薄层板上采用双波长扫描法测定不同厂家生产的正青风痛宁片中青藤碱的含量,以甲苯－乙酸乙酯－甲醇－水（2：4：2：1）上层清液,每10毫升加0．04ml浓氨水作为展开剂;双波长反射法锯齿扫描,测定波长为λs=275nm,λR=320nm,结果：通过方法的考察表明,青藤碱点样量在1．235－7．400ug范围内成良好的线性关系,平均回收率为99．87％,（RSD＝0．94％,n=5)。结论：实验表明,操作简便快速,数据准确,板间误差小,方法可靠。 相似文献
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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
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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
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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
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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
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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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《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love. 相似文献