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61.
川芎茶调散及其4种改型制剂的质量分析   总被引:1,自引:0,他引:1  
目的:考察川芎茶调散改型制剂的质量,分析影响质量的工艺因素。方法:按中国药典检测方法对各制剂所含挥发油及浸出物进行定量分析,并用TLC法对各制剂进行川芎、白芷的主成分鉴别。结果:挥发油含量最高为0.4%(散剂、片剂),最低为0.085%(袋泡剂);醇溶性浸出物最高为15.76%(散剂),最低为10.23%(冲剂);水溶性浸出物最高为24.89%(散剂),最低为18.43%(袋泡剂);袋泡剂中川芎、白芷的TLC鉴别为阴性。结论:与散剂相比,4种改型制剂均存在不同程度的质量问题,其中冲剂、袋泡剂各项指标最低,提示单纯以水提取的剂改工艺欠合理  相似文献   
62.
BACKGROUND: Sevoflurane has a lower blood:gas partition coefficient than isoflurane and thus should be associated with a more rapid recovery from anaesthesia. METHODS: A review and meta-analysis were employed to examine the recovery profiles of adult patients following anaesthesia, comparing sevoflurane to isoflurane and sevoflurane to propofol. RESULTS: There were significant differences in times to several recovery events that favoured sevoflurane to isoflurane anaesthesia, including time to emergence, response to commands, extubation, and orientation. Likewise, there were significant differences in times to the same recovery events following anaesthesia with sevoflurane versus propofol. There were no differences in time to recovery room discharge when comparing sevoflurane to isoflurane or propofol. CONCLUSION: The observed differences between sevoflurane and isoflurane or propofol anaesthesia support the postulate that the use of sevoflurane is associated with a more rapid recovery from anaesthesia than either isoflurane or propofol.  相似文献   
63.
地砷病患者部分生化指标的测定   总被引:2,自引:0,他引:2  
对病区地砷病、非地砷病患者及对照组居民体内的部分生化指标进行了检测。结果表明,地砷病患者血清中的GPT活性、UN和SA含量明显高于对照组,LDH及GSHPx活性明显降低;病区非地砷病患者LDH活性、SA含量明显升高,GSHPx活性明显降低,其它各组及各指标与对照组相比无显著差异。相关分析显示,病区病人组及非病人组血中SA含量与各自尿砷水平呈正相关(r=050,r=046),GSHPx与尿砷呈负相关(r=-051,r=-048)。提示,SA和GSHPx可作为砷中毒的早期诊断指标。砷可能对接砷居民肝功、肾功产生一定影响。  相似文献   
64.
坦克作业条件下驾驶室内挥发性有机物定性分析   总被引:5,自引:2,他引:3  
目的:了解某型坦克作业条件下驾驶室内挥发性有机物的污染状况,为制定防治措施提供科学依据。方法:应用气相色谱-质谱联用技术(GC-MS)对某型坦克单纯行进,行进打炮,停车打炮等工作状态下驾驶室内以及废气排放口的挥发性有机物(VOCs)进行了全谱分析,结果:共检出134种污染物质,包括脂肪烃类,单环芳烃类,多环芳烃类以及机酸,碱,酯,醛,酮,杂环化合物等。结论:实验结果表明这些物质主要来源于油类蒸汽,  相似文献   
65.
本实验用具备胆瘘的大鼠颈静脉恒速灌注肝胆酸钠10μmol/(100g·h)维持胆汁酸池恒定条件下,观察电针“曲泉”穴对肝胆汁分泌的影响及与受体的炎系。结果表明:电针“曲泉”穴,胆汁流量、胆汁K~+、Na~+、Cl~-、HCO_3~-排出量均显著增加,(P<0.01),但不影响胆酸的排出量。说明电针“曲泉”穴有利胆作用,所刺激肝胆汁本属不依赖胆汁酸部分。在本实验条件下,静脉给予阿托品(0.2mg/kg),酚妥拉明2.5mg/(kg·h))、心得安(5mg/kg)对胆汁分泌无显著影响,但阿托品有加强其利胆效应的倾向(P>0.05),而心得安则完全抑制其效应(P<0.01)。结果表明:“曲泉”穴的利胆效应与β受体有关,与α受体关系不大,并提示M受体或阿托品及体液因素如促胰液素,胰高血糖素等亦可参与“曲泉”穴的利胆机制。  相似文献   
66.
本文报道1990年版药典收载的花椒Zanthoxylum bungeanum Maxim、青椒z sehinifolium Sieb.et Zucc,以及其他3个药用种毛竹叶椒z armature f ferrugineum(R·et W.)Huang、朵椒z molle Rehd.、椿叶花椒z.ailanthvide8 Sieb.et Zucc,共5种8个样品果皮挥发油含量,并对其中4个样品挥发油进行了GC-MS分析。结果显示同种不同产地及不祠植物来源的花椒果皮挥发油含量及组成差异很大。  相似文献   
67.
This study has analyzed variations in the number of nucleoli and nuclear bodies, as well as in their ultrastructural and cytochemical organization, after the osmotically induced activation of supraoptic nucleus (SON) neurons of the rat. The number of nucleoli and nuclear bodies and also the nucleolar size were determined on smear preparations of previously block-impregnated SON. The mean number of nucleoli per cell was 1.35 +/- 0.6 (mean +/- SDM) in control rats. No significant variations in this value were registered either in dehydrated or rehydrated rats. The mean nucleolar volume and the total nucleolar volume per cell showed a significant increase in dehydrated rats with respect to the controls, whereas these two parameters tended to return to control values in rats rehydrated after dehydration. The mean number of nuclear bodies per cell increased significantly from 0.56 +/- 0.50 (mean +/- SDM) in control rats to 1.54 +/- 1.1 after 6 days of dehydration. By electron microscopy, SON neurons displayed a reticulated nucleolar configuration. After the osmotically induced neuronal activation, there was an increase in the proportion of the total nucleolar area occupied by the granular component, and also a reduction in the mean fibrillar-center area. The most characteristic nucleolar features in rehydrated rats were the tendency for the granular component to be segregated and the occurrence of intranucleolar vacuoles. Ultrastructural cytochemistry with a specific silver method revealed a selective silver reaction on the coiled threads of the nuclear bodies--identified as "coiled bodies"--and on the nucleolar fibrillar components in all animal groups studied. Since nucleoli play a major role in ribosome biogenesis, a relationship between these nucleolar changes and the level of cellular activity of SON neurons is proposed. Furthermore, the response of nuclear "coiled bodies" to neuronal activation suggests their participation in the processing and transport of rRNA precursors.  相似文献   
68.
Summary The reactions of adenosine 14C- and 32P-labelled ATP with isolated membranes from catecholamine storage vesicles of the bovine adrenal medulla were studied. In presence of Mg2+ about twice as much of 32P-radioactivity combined with the membrane as 14C-adenosine compounds at 31°C and also at 0°C, while in the absence of Mg2+ the amounts of 14C and 32P incorporated were similar for both substances. Autoradiography of the SDS-polyacrylamide gel after electrophoresis of the 32P-ATP-treated membrane protein showed two distinct zones corresponding to protein bands. Sonication released twice as much 32P-ATP as 14C-ATP from the space within the membrane particles indicating that at least half of the ATP present in this space did not contain its original terminal phosphate group. About 40–45% of the 32P-radioactivity was incorporated in the membrane lipids, whereas only small amounts of 14C-radioactivity were extracted with the lipids. About 1/3 of the incorporated 14C-radioactivity was not extractable with acids. The same amount remained in the 32P-ATP treated preparation acid-stably bound after extraction of the lipids and thus must be firmly bound ATP. When the reaction of the membrane preparation with labelled ATP was performed at 0°C the fractions of the acid-stably bound 32P- and 14C-radioactivity increased. About 1 nmole/mg of protein (10–15%) of the bound 32P-radioactivity was exchangeable against unlabelled ATP, while only a very small fraction (<0.5 nmole/mg protein) of the 14C-radioactivity was exchanged against unlabelled ATP. Preincubation of the membrane particles with ATP-Mg2+ at 0°C induced 30% inhibition of the ATPase activity and abolition of the net uptake of catecholamines. Different K m values obtained from initial velocity studies of ATPase activity and the overall-incorporation of 32P-radioactivity indicated that a direct correlation between these processes did not exist. Different strong inhibitory effects exerted by ADP on the ATPase activity and net uptake of catecholamine at the one hand and the overall 32P- and 14C-incorporation at the other hand supported that view. It is concluded that only small fractions of the observed 32P-and 14C-incorporation can be involved in the ATP-hydrolyzing reaction.  相似文献   
69.
 目的测定利福平及氯诺昔康中有机溶剂残留量。方法毛细管气相色谱柱顶空进样法,FID检测器。利福平以5%苯基甲基聚硅氧烷为固定相,柱温50℃;氯诺昔康以聚乙二醇为固定相,柱温50℃维持15min,以10℃·min-1的速率升温至165℃,维持5min。结果甲醇、丙酮、氯仿、正丁醇线性关系r分别为0.9999,0.9999,0.9984,0.9998;平均回收率分别为96.0%,97.3%,81.1%,93.9%,RSD分别为2.7%,1.9%,8.8%,2.5%(n=5)。结论方法柱效高、灵敏、准确,适用于利福平及氯诺昔康中有机溶剂残留量测定。  相似文献   
70.
益母草的化学、药理和临床研究进展   总被引:50,自引:0,他引:50  
阮金兰  杜俊蓉  曾庆忠  钱忠明 《中草药》2003,34(11):1069-1073
查阅近20年有关文献,对益母草的化学成分、药理作用、临床应用研究进展进行综述。益母草主要含有生物碱类、黄酮类、二萜类、脂肪酸类、挥发油类等化合物;药理作用研究证明其具有调经止血、保护心肌缺血再灌注损伤、抗血小板聚集、降低血液黏度等作用;在临床上常用来治疗流产后出血、冠心病、心肌缺血、高黏血症、痛经等疾病。益母草具有广泛的药理活性,对其药效学物质基础进行深入研究和开发,将具有重要意义。  相似文献   
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