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71.
白花前胡丙素与类似物的化学沟通   总被引:1,自引:1,他引:0  
目的:将白花前胡丙素与其类似物进行化学沟通,为进一步进行结构修饰奠定基础。方法:控制碱水解条件,得到白花前胡丙素的三个水解产物,采用在二氯甲烷溶剂中与相应的酸直接酰化的方法得到各种类似物。结果:合成了三种白花前胡有类似物,即3‘(S)-当归酰氧基-4‘(R)-异戊酰氧基-3‘,4‘-二氢邪蒿内酯、3‘(S),4‘(S)-二乙酰氧基-3‘,4‘-二氢邪蒿内酯和3‘(S),4‘(R)-二乙酰氧基-3‘,4‘-二氢邪蒿内酯。结论:合成的三个白花前胡丙素的类似物中,两个为新化合物,一个为已知的天然产物。  相似文献   
72.
反义hTR基因瘤内注射对荷瘤鼠肿瘤治疗作用的初步观察   总被引:2,自引:0,他引:2  
目的 观察反义人端粒酶RNA(hTR)基因瘤内注射对荷瘤鼠肿瘤的治疗作用。方法 人胃癌细胞株SGC-7901裸鼠背部皮下接种,成瘤后于瘤内多点注射FuGENETM6/反义hTR表达质粒复合物,设FuGENETM6稀释液为对照,观察肿瘤生长情况和肿瘤组织学结构变化。 结果 治疗组肿瘤生长速度明显减慢,治疗1个月瘤体较对照组小23%,瘤组织中的瘤细胞排列较稀疏并形成较多的腺样结构,显示有分化倾向。结论 反义hTR基因瘤内注射对荷瘤鼠肿瘤有一定的治疗作用,值得进一步研究。  相似文献   
73.
目的:评价三种药物防治胃肠肿瘤化疗所致呕吐的价值。方法:90名患者随机分成三组,灭吐灵组(A组),吗丁啉组(B组),枢丹组(C组)。应用5-Fu+LV方案化疗5天,观察5天内三种药物的止吐效果。结果:A和B、C组比较有显著性差异(P〈0.05),B和C比较无显著性差异(P〉0.05)。结论:B组副作用少,疗效高,建议临床推广使用吗丁啉。  相似文献   
74.
山萸肉化学成分及其药理活性的研究   总被引:25,自引:0,他引:25  
近年来 ,对山萸肉的药理研究多采用单味药的粗浸煎剂 ,不利于明确真正发挥药效的部位和成分。本文概述了山萸肉中的主要成分及其药理活性 ,有助于进一步研究药物的构效关系及研制开发新药。  相似文献   
75.
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   
76.
铁路危险品货运站空气污染指标的探讨   总被引:2,自引:2,他引:0  
铁路危险品货运站(危货站)空气污染物种类多,空气污染严重,为探讨对其监测和评价的综合性能指标和方法,采用空气耗氧量(AOD)和SOS致遗传毒性原位监测法(SOS原位法),分别对危货站空气污染进行了研究。结果表明,危货站中各点所测AOD值与对照区AOD值,在统计学上差异均有显著性(P〈0.05)。SOS原位法显示,随采样体积的增加,β-半乳糖苷酶的量也增加,采样体积与酶诱导率之间存在剂量-反应关系。  相似文献   
77.
Recent researches on the rickettsial group microorganisms are summarized in their comparative aspects of morphology, cultivation and multiplication, susceptibility to chemotherapeutics, chemical structure of envelopes, nucleic acid, protein constitution, and gene structures. From this overview, Rickettsia tsutsugamushi seems to have different properties from the others and should be reclassified into a new genus, and a new species name as Orientia tsutsugamushi is proposed.Presented at the 4th International Symposium on Rickettsiae and Rickettsial Diseases, Pietany, C.S.F.R., 1–6 October, 1990.  相似文献   
78.
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   
79.
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   
80.
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   
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