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排序方式: 共有397条查询结果,搜索用时 31 毫秒
1.
目的测定不同种类人参,人参不同部位中,红参加工过程中人参皂苷Ro(简称Ro)和姜状三七皂苷R1(简称R1)的含量含量。方法:采用HPLC的方法,对样品预处理及色谱条件进行优化。结果:鲜参中Ro和R1含量比红参中含量高;不同部位中Ro和R1的含量差异为:芦头参须主根;红参加工过程中的蒸制使Ro含量升高,R1含量降低。结论本文所建立的人参中人参皂苷Ro和姜状三七皂苷R1的含量测定方法准确、稳定可靠。  相似文献   
2.
Zhou W  Di LQ  Shan JJ  Bi XL  Chen LT  Wang LC 《Fitoterapia》2011,82(3):375-382
Shuang-Huang-Lian (SHL), a traditional Chinese formula containing Lonicerae japonicae flos (LJF), Scutellariae radix (SR) and Forsythiae fructus (FF), is commonly used to treat acute upper respiratory tract infection, acute bronchitis and light pneumonia. Forsythoside A is one of the main active ingredients in Forsythiae fructus, a key herb in SHL. In the present study, effects of different compositions in SHL on the intestinal absorption of forsythoside A were investigated. The observations from in situ intestinal circulation model showed that A/%(h− 1) of forsythoside A in FF + LSF, FF + SR and SHL were all reduced greatly compared with that in FF. However, in pharmacokinetics study, Cmax and AUC0 → 1440 of forsythoside A all increased and T1/2 prolonged in SHL, FF + LJF and FF + SR compared with FF. The results indicated that the different compositions of SHL decreased absorption but increased bioavailability of forsythoside A, which may be related to its metabolism inhibited in intestine or liver.  相似文献   
3.
为分析不同粒度黄芩颗粒纤维构成及黄酮含量的差异性,以5种黄芩为研究对象,分别对不同品种、不同粒度的黄芩样品中木质素、半纤维素和纤维素等纤维构成及黄芩甙、汉黄芩甙、黄芩素和汉黄芩素等主要黄酮含量进行了测定。通过方差分析发现,不同粒度黄芩中纤维构成、黄芩甙、黄芩素和总黄酮含量差异显著(P<0.05),汉黄芩甙和汉黄芩素含量无显著性差异(P>0.05)。  相似文献   
4.
为评价新兽药"芪蓝饮"及其不同提取成分的体外抗病毒活性,本试验通过细胞病变抑制法和MTT比色法检测了各提取成分对新城疫病毒(NDV)感染鸡胚成纤维细胞(CEF)过程的影响。结果显示,在3种加药方式中"芪蓝饮"原药(QLY)直接杀灭NDV的作用最强,其抑制率最高为128.85%;原药总多糖(TPS)干扰NDV的增殖作用最强,其抑制率最高为130.23%;原药总萜类(TT)直接杀灭NDV的作用最强,其抑制率最高为146.15%;板蓝根总生物碱(RIA)及其水溶性部位(RIAw)和酸性部位(RIAa)对抗NDV的方式是多环节的。综上所述,"芪蓝饮"及其提取成分表现出较强的干扰NDV增殖和直接杀灭NDV的作用,而阻断作用稍弱。  相似文献   
5.
以威灵仙根部为原料,采用黄酒用量、干燥条件、提取时间三因素,三水平的L9(34)正交试验设计,以水煎物干膏提取率、薄层层析检测威灵仙中的三萜皂苷为主要考核指标。结果表明:黄酒用量对威灵仙总皂苷提取率有极显著影响,烘干条件有显著影响,提取时间对试验结果影响不显著,表明影响因素最大的是黄酒用量,其次是干燥条件。  相似文献   
6.
复方板蓝根提取工艺与靛玉红含量测定   总被引:1,自引:0,他引:1  
通过正交试验优选出复方板蓝根最佳的提取工艺,并建立反相高效液相色谱法(Reverse Phase High Performance Liquid Chromatography,RP-HPLC)测定该复方的靛玉红含量。含量测定采用外标法。结果表明不同工艺的提取方法中,加10倍水,煎煮1次,煎煮时间为2h的提取工艺,含量最高,达6.86μg/mL;HPLC法测定靛玉红,其线性范围在2.0~20.0μg/mL内靛玉红的含量与峰面积相应值呈良好的线性关系(r=0.972),平均加样回收率为96.54%(n=6),说明HPLC方法简便、准确、重复性好,可作为该产品质量控制方法。  相似文献   
7.
本文针对英语字典中单词排列的特点和基数排序的思想,将基数排序应用于英语单词排序中。得到了单词的链式基数排序法。  相似文献   
8.
In order to explore the antibacterial activity and mechanism of the Radix isatidis powder water extract,the effects of the Radix isatidis powder water extract on the morphology and structure of Escherichia coli (E.coli) were tested by scanning electron microscopy and transmission electron microscopy.The effects of the Radix isatidis powder water extract on the conductivity and total leakage rate of E.coli and the content of alkaline phosphatase in the culture medium of the content of protein,DNA and RNA were stained by DAPI to detect the effect of the Radix isatidis powder water extract on the nucleic acid of E.coli,and the effect of the Radix isatidis powder water extract on the metabolism of E.coli in vivo,in vitro,ALT,AST,pyruvic acid and ATP.The results showed that after the Radix isatidis powder water extract acted on E.coli for 10 h,it was observed by SEM that the bacteria appeared to overflow and shrink,the length of the bacteria became shorter obviously,many residues were formed due to breakage,some of them were sunken in the middle and deformed.Under TEM,it was observed that the boundary of the cell wall of E.coli was unclear,the wall membrane was zigzag,deformed and some of the bacteria were broken.The protein content outside the cell was significantly different from that in the blank control group from 8 h (P<0.01), and that in the cell from 4 h (P<0.01). DNA content had no significant difference with blank control group before 12 h (P>0.05), but had significant difference with blank control group from 16 h (P<0.01); RNA content began to decrease at 8 h, and was significantly different from blank control group at 12 h (P<0.05), and was extremely significant from 16 h (P<0.01). There was no significant difference between ALT and AST (P>0.05). The pyruvate content in culture medium and bacteria was higher than that in blank control group, and the difference was very significant from 4 h (P<0.01). The ATP content in the culture medium was significantly different from that in the blank control group (P<0.01), and the ATP content in the cell was significantly different from that in the blank control group from 4 h (P<0.01).In conclusion,the Radix isatidis powder water extract could inhibit the synthesis and metabolism of bacterial genetic material and the content of pyruvate and ATP by destroying the integrity of cell wall and cell membrane.  相似文献   
9.
复方黄芩颗粒剂对小鼠免疫功能的影响   总被引:4,自引:0,他引:4  
研究复方黄芩颗粒剂对昆明小鼠免疫功能的影响。应用复方黄芩颗粒给小鼠灌胃10 d后,分别测定对照组与实验组胸腺指数、脾脏指数和血清中的免疫球蛋白IgAI、gGI、gM和补体C3、C4;并且进行体外实验,用不同浓度的复方黄芩颗粒剂对小鼠脾脏淋巴细胞进行体外培养,测定淋巴细胞转移刺激指数(SI);在体外培养测定细胞吞噬中性红的能力。与对照组相比,试验组的胸腺指数、脾脏指数、免疫球蛋白和补体C3、C4都升高且显著水平为差异显著(P<0.05);脾脏淋巴细胞转移刺激指数均极显著地高于对照组(P<0.01),75μg/mL组的脾脏淋巴细胞转移刺激指数达最高;腹腔巨噬细胞具有一定的吞噬能力,吞噬中性红能力与剂量成依赖关系。结论:复方黄芩颗粒剂在一定程度上有提高小鼠免疫功能的作用。  相似文献   
10.
北京鸭口服AFB_1的慢性中毒实验中,分别采用白芍粉和白芍醇提物进行防治。根据肝脏组织学病变等观察结果,表明白芍醇提物和白芍粉对AFB_1所导致北京鸭肝癌有一定的抑制作用。提示从雏鸭开始,间断给予冲击性剂量的AFB_1,可能有助于肝癌的形成。大剂量白芍对肝脏可造成一定程度的损害,这种损害与肝癌的发生并不完全相关。  相似文献   
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