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1.
银杏叶精油的化学成分   总被引:3,自引:0,他引:3  
采集3-5年银杏苗叶,经常压水蒸汽蒸馏制得浅黄色精油,通过GC和GC/MS鉴定出44个化学成分,主要由31.14%烃类、5.61%醇类、1.78%醛类、46.17%酮类、5.41%酸类和1.1%酯类组成。在酮类中以六氢法呢酮含量最高,占11.15%,其次为橙花基酮(8.68%)和β-紫罗兰酮(5.24%)。  相似文献   

2.
高效液相色谱分析银杏萜内酯的含量   总被引:3,自引:0,他引:3       下载免费PDF全文
李典鹏  方宏  梁小燕  陈海珊  文永新   《广西植物》1999,19(3):282-284
用高效液相色谱法测定银杏叶及提取物中银杏内酯中A、B、C和白果内酯的含量。采用C18分离柱,示差检测器,甲醇:水(33:67)为流动相,方法回收率平均达97%以上,变异系数(CV)为2.1%。  相似文献   

3.
高效液相色谱分析银杏萜内酯的含量   总被引:2,自引:0,他引:2  
李典鹏  方宏  梁小燕  陈海珊  文永新   《广西植物》1999,19(3):282-284
用高效液相色谱法测定银杏叶及提取物中银杏内酯A、B、C和白果内酯的含量。采用C18分离柱,示差检测器,甲醇:水(33:67)为流动相,方法回收率平均达97%以上,变异系数(CV)为2.1%。  相似文献   

4.
蝴蝶兰根段的组织培养   总被引:38,自引:2,他引:36  
1 植物名称 蝴蝶兰(PhalaenopsisMellerGold“NFS”)。2 材料类别 根段。3 培养条件 (1)愈伤组织的诱导及分化培养基:B5+NAA1.5mg·L-1(单位下同)+KT0.2+CM150ml·L-1+3%蔗糖;(2)原球茎增殖培养基:B5+GA0.05+CH120+3%蔗糖;(3)小苗生长培养基:1/2MS+20%香蕉泥+2%蔗糖;(4)诱导生根培养基:1/2MS+IBA0.3+2%蔗糖。上述培养基均加0.2%活性炭,0.58%琼脂粉,pH为5.5;培养基在121℃高…  相似文献   

5.
产纤维素酶菌株宇佐美曲霉Y-11产酶条件及酶性质的研究   总被引:4,自引:0,他引:4  
通过正交试验,对宇佐美曲霉纤维素酶固态发酵条件进行了研究,其较适培养基为:麸皮与稻草配比为2:3,氮源:尿素,含水量:200%(液固比),pH:5.5。28-30℃培养72小时,CMC酶活力为5.05(u/ml),滤纸酶活力达到1.04(u/ml)。CMC酶及滤纸酶最适pH分别为4.41、6.06;最适温度分别为65℃、55℃。酶的热稳定性与pH稳定性较高。  相似文献   

6.
NA和5-HT对小脑脑片浦肯野细胞自发及诱发电活动的影响   总被引:2,自引:0,他引:2  
在大鼠小脑脑片上观察了NA和5-HT对浦肯野细胞(PC)的自发放电活动及由白质刺激所引起的诱发放电活动的影响。结果表明:(1)NA使PC产生抑制、兴奋和双相反应,以抑制反应为主(79.8%);5-HT引起PC兴奋和抑制反应,以兴奋反应略多(57.8%)。(2)先后灌流NA和5-HT对同一个PC自发放电的影响主要为抑制(NA)-兴奋(5-HT)(53.8%)。(3)NA对PC的诱发复杂锋电位(CS)和简单锋电位(SS)反应,主要产生增强效应(57.1%和62.8%);5-HT对PC诱发CS和SS反应则主要产生压抑作用(60.0%和68.2%)。(4)先后灌流NA和5-HT对同一个PC的诱发CS和SS反应,主要表现为NA对这两种诱发反应的增强和5-HT的压抑效应(60.0%和52.9%)。这些结果提示,NA能和5-HT能传入纤维可以通过释放NA和5-HT调节PC的兴奋性水平并改变PC对爬行纤维和苦状纤维突触传入的反应敏感性,影响小脑皮层神经元网络的感觉运动整合过程。  相似文献   

7.
实验应用复合式肠内细菌群检测法,随机比较了中国大连地区和日本大阪地区6 名健康成年人( 简称:CA,JA) 及4 名老年人( 简称:COM,JOM) 的肠内细菌群结构。CA 肠内细菌总数为10.21 ±5.56( 每克粪便中的对数值) ,较JA 的肠内细菌总数10.87 ±2.45 低,但统计学检查差异不显著;CA 的双歧杆菌数为9.01 ±0.13 ,JA 的双歧杆菌数为9.98 ±1.24 ,统计学检查表明差异显著,而且,JA 的双歧杆菌占有率为12.88 % ±3.45 % 明显高于CA 的6.29 % ±4.55 % ,统计学检查差异显著。CA 的乳酸菌数为5.45 ±1.12 ,JA 的乳酸菌数为5.52 ±1.44 ;在腐败梭菌的菌数上,CA 为6.45 ±2.21 比JA 的5.22 ±2.45 略高,但统计学检查差异不明显。COM 肠内细菌总数为10.45 ±4.66 ,较JOM 的肠内细菌总数10.97 ±5.25 低,但统计学检测差异不显著;COM的双歧杆菌数为8.74 ±2.13 ,JOM 的双歧杆菌数为9.85 ±0.34 ,统计学检查表明差异显著,而且,JOM 的双歧杆菌占有率为7.59 ±5.15 % 明显高于COM 的1.13 % ±0  相似文献   

8.
5—羟色胺对肺动脉平滑肌细胞在缺氧条件下增殖的作用   总被引:2,自引:1,他引:1  
刘健  王培勇 《生理学报》1997,49(3):292-298
本研究应用细胞培养、^3H-TdR掺入,核酸分子杂交、免疫组织化学染色技术,探讨无氧(0%O2+95%N2+5%CO2)和/或低氧(2.5 ̄3%O2+92%N2+5%CO2)对新生小牛肺动脉平滑肌细胞增殖和5-羟色胺转载体基因表达的影响。结果表明:无氧24h可刺激PASM的DNA合成,^3H-TdR的掺入增加(P〈0.05),加入5-羟色胺能非常显著地促进无氧PASM增殖(P〈0.001),而对常  相似文献   

9.
应用细胞内记录,研究了豚鼠腹腔神经节(CG)细胞非胆碱能迟慢兴奋性突触后电位(LS-EPSP)与5-羟色胺(5-HT)及P物质(SP)的相互关系。当重复电刺激内脏大神经(SN)时,有78.2%的细胞(161/206)在动作电位发放后出现LS-EPSP,灌注或压力注射5-HT或SP,分别在68.5%的细胞(102/149)及52.1%的细胞(98/188)上引起5-HT或SP去极化反应,两者差异非常显著(P<0.01);大部分具有LS-EPSP的细胞对5-HT(73/88,83.0%)或SP(68/11459.6%)敏感,而不出现LS-EPSP的细胞仅有少数对5-HT(10/26,38.5%)或SP(11/36,30.6%)敏感,两类细胞的差异非常显著(5-HT:P<0.0001,SP:P<0.01)。上述结果支持5-HT与SP均作为递质参与LS-EPSP形成的观点。此外,在133个细胞上同时检测了5-HT与SP的作用,其中有66个细胞(49.6%)对5-HT及SP均敏感,提示在CG细胞,5-HT与SP之间可能存在某种机能联系。  相似文献   

10.
应用ELISA和PCR法检测502例乙肝病人血清,401例HBsAg阳性血清中,有114例(28.4%)抗-HCV和HCVRNA双项阳性,25例(6.2%)HCVRNA单项阳性;21例(5.2%)抗-HCV单项阳性。将HBsAg乙肝病人分成HBVDNA,HBeAg阳性组和HBVDNA,HBeAg阴性组。前者抗-HCV阳性率为11.6%~20.5%,HCVRNA阳性率为16.2%~20.5%。后者抗-HCV阳性率为20.2%~55.6%,HCVRNA阳性率为23%~60.3%。结果说明长期携带HBV者和慢性乙肝病人均可重叠HCV感染。HBVDNA阳性组抗-HCV和HCVRNA阳性率明显高于HBVDNA阳性组  相似文献   

11.
Abstract: The effect of Ginkgo biloba extract (EGb 761) treatment (100 mg/kg/day, per os, for 14 days) on electroconvulsive shock (ECS)-induced accumulation of free fatty acids (FFA) and diacylglycerols (DAG) was analyzed in rat cerebral cortex and hippocampus. EGb 761 reduced the FFA pool size by 33% and increased the DAG pool by 36% in the hippocampus. These endogenous lipids were unaffected in cerebral cortex. During the tonic seizure (10 s after ECS) the fast accumulation of FFA, mainly 20:4, was similar in sham- and EGb 761 -treated rats, in both the cerebral cortex and hippocampus. However, further accumulation of free 18:0 and 20:4, observed in the hippocampus of sham-treated rats during clonic seizures (30 s to 2 min after ECS), did not occur in EGb 761-treated animals. The rise in DAG content triggered in the cortex and hippocampus by ECS was delayed by EGb 761 treatment from 10 s to 1 min, when values similar to those in sham animals were attained. Moreover, in the hippocampus the size of the total DAG pool was decreased by 19% during the tonic seizure. At later times, DAG content showed a faster decrease in EGb 761-treated rats. By 2 min levels of all DAG acyl groups decreased to values significantly lower than in sham animals in both cortex and hippocampus. This study shows that EGb 761 treatment affects, with high selectivity, lipid metabolism and lipid-derived second messenger release and removal in the hippocampus, while affecting to a lesser extent the cerebral cortex.  相似文献   

12.
EGb761 produces reversible inhibition of both monoamine oxidase (MAO) isoforms in the central nervous system. 1-Methyl-4-phenylpyridinium (MPP+) neurotoxicity is prevented by treatment with the MAO inhibitor pargyline. We investigated EGb761's effect on striatal MAO activity during MPP+ neurotoxicity. C-57 black mice were pretreated with EGb761 (10 mg/kg) daily for 17 days followed by administration of MPP+ (0.72 mg/kg). MPP+ enhanced striatal MAO (30%) activity at 6 h, and EGb761 prevented this effect. MAO-B activity in striatum was enhanced (70%) 6 h after MPP+ administration and was reduced to almost normal levels in EGb761 + MPP+ group compared to MPP+ group. Pretreatment with EGb761 partially prevented (32%) the striatal dopamine-depleting effect of MPP+ and prevented the reduction in striatal tyrosine hydroxylase activity (100%). Results suggest that EGb761 supplements may be effective in reducing MAO activity as well as enhancement in dopamine metabolism, thereby preventing MPP+-neurotoxicity.  相似文献   

13.
EGb 761, a standardized extract of Ginkgo biloba leaves, has been used in clinical trials for its beneficial effects on brain functions. In mammals, EGb 761 has been shown to enhance cognition, stress resistance, and longevity, but its molecular and cellular mechanisms are not known. In the present investigation, we used the model organism Caenorhabditis elegans to evaluate pharmacological effects of EGb 761 on aging. We tested the theory that EGb 761 augments the natural antioxidant system of C elegans, and thus increases stress resistance and longevity. We found that treatment of the wild-type worms with EGb 761 extended their median life span by 8%. Amongst several purified components of EGb 761, the flavonoid tamarixetin showed the most dramatic effect: it extended the median life span by 25%. Furthermore, EGb 761 increased the wild type's resistance to acute oxidative and thermal stress by 33% and 25%, respectively. Treatment of the prematurely aging mutant worms mev-1 with EGb 761 increased their resistance to acute oxidative and thermal stress by 33% and 11%, respectively. It appears that oxidative stress, a major determinant of life span, as well as other types of stress, can be successfully counteracted by the Ginlkgo biloba extract EGb 761.  相似文献   

14.
The present study was conducted to evaluate the different effects of the constituents of EGb761 (Ginkgo biloba Extract) on apoptosis in cerebellar granule cells induced by hydroxyl radicals. The total flavonoid component of EGb761, two pure EGb761 components (rutin and quercetin), and a mixture of flavonoids and terpenes protected cerebellar granule cells from oxidative damage and apoptosis induced by hydroxyl radicals. ESR(electron spin resonance) results showed that the IC50 of the flavonoids for scavenging hydroxyl radicals was almost the same as that of EGb761, even though flavonoids make up only 24% of EGb761, implying that other constituents of EGb761 besides flavonoids can scavenge hydroxyl radicals. Total terpenes of EGb761 did not protect against apoptosis. Flavonoids and terpenes did not show a synergistic effect in this regard. Terpenes did not scavenge hydroxyl radicals directly, which might be related to their "cage-like" structures.  相似文献   

15.
Ginkgo biloba extract EGb 761 was studied for its nephroprotective effects in experimentally diabetic and hypoxic rats. Duration of streptozotocin-induced diabetes was 4 months, that of respiratoric hypoxia of the diabetic group 20 min. The daily dose of 100 mg EGb/kg bodyweight started 1 month after induction of the diabetes. EGb reduced diabetes-induced morphological alterations of the kidney such as increase in volume of glomeruli, capillary tufts, urinary space, and thickening of Bowman's capsule basement membrane. Diabetically increased immunostaining of interstitial collagenes of types I, III, and VI was diminished by the EGb extract. EGb reduced the relative total SOD activity from 163% in diabetic kidney to 46%. Additional hypoxia-induced ultrastructural damage was also diminished.  相似文献   

16.
银杏叶提取物对糖尿病大鼠心肌损伤的防护作用   总被引:9,自引:0,他引:9  
Li XS  Chen GR  Li JM  Hu Y  Wang F  Hu Y 《中国应用生理学杂志》2005,21(2):176-178,i003
目的:研究银杏叶提取物(EGb)对糖尿病大鼠心肌的防护作用.方法:用光镜和透射电镜观察EGb对糖尿病大鼠心肌的形态学改变,并测定心肌组织内超氧化物歧化酶(SOD)、一氧化氮合酶(NOS)、结构型一氧化氮合酶(cNOS)、诱导型一氧化氮合酶(iNOS)的活性及一氧化氮(NO)、丙二醛(MDA)的含量.结果:糖尿病大鼠心肌光镜下主要表现为心肌细胞空泡变性及心肌纤维局灶性溶解;电镜下主要表现为心肌线粒体肿胀,嵴变短,肌原纤维溶解;SOD活性下降,NOS、iNOS活性及MDA、NO含量增高.EGb治疗组病变明显减轻,EGb治疗组心肌组织内SOD活性明显高于糖尿病组,NOS、iNOS活性及MDA、NO含量低于糖尿病组.结论:EGb可能通过抗脂质过氧化作用和降低NO水平而对糖尿病心肌产生保护作用.  相似文献   

17.
目的:探讨EGb761对LPS诱导THP-1细胞释放HMGB1蛋白表达的调节,为EGb761的临床运用提供可行的依据。方法:LPS(1μg/m L)诱导不同时间后,western blotting检测THP-1细胞上清液中HMGB1蛋白含量变化及不同浓度EGb761对LPS诱导THP-1细胞释放HMGB1蛋白的表达和NF-κB的活性;酶联免疫吸附法(ELISA)检测细胞中IL-1β、IL-6、TNF-α的含量。共聚焦显微镜观察EGb761对LPS诱导THP-1细胞释放HMGB1蛋白核转位变化。结果:(1)LPS组IL-1β、IL-6、TNF-α的含量在刺激6-12 h后明显高于空白对照组,而EGb761+LPS组IL-1β、IL-6、TNF-α的含量均显著低于LPS组(P0.05)。(2)EGb761处理LPS诱导THP-1细胞6 h后细胞上清液NF-κB活性表达量较空白对照组低,随着处理时间延长至12 h,NF-κB的活性表达量呈明显下降趋势(P0.05)。(3)LPS诱导THP-1细胞18 h后,细胞上清液中HMGB1蛋白含量呈明显升高趋势(P0.05)。(4)不同浓度EGb761对LPS诱导THP-1细胞18 h后,HMGB1蛋白含量较空白对照组有下降趋势,HMGB1蛋白含量随着EGB761浓度增加至100μg/m L呈下降趋势并呈浓度依赖效应(P0.05)。(5)LPS诱导THP-1细胞后,在共聚焦显微镜下可见胞浆中大量HMGB1蛋白标记分布,而EGb761+LPS共同诱导THP-1细胞后胞浆中可见少量HMGB1蛋白分布。结论:LPS可诱导THP-1细胞IL-1β、IL-6、TNF-α表达增多及NF-κB活化,导致HMGB1蛋白表达增多及核转位,而EGB761能抑制THP-1细胞IL-1β、IL-6、TNF-α表达及NF-κB活化,调节HMGB1蛋白的表达及核转位。  相似文献   

18.
Restenosis may develop in response to cytokine activation and smooth muscle cell proliferation. Ginkgo biloba extract (EGb) has been used to treat cardiovascular and cerebrovascular diseases. In the present study, the effects of EGb on the growth of cultured vascular smooth muscle cells (VSMC), as well as on the expression of interleukin-1beta (IL-1beta) and the intimal response in balloon-injured arteries of cholesterol-fed rabbits, were investigated. Using bromodeoxyuridine incorporation as an index of cell proliferation, EGb was found to inhibit serum-induced mitogenesis of cultured rat aorta VSMC in a dose-dependent manner. In vivo, EGb and probucol ( positive control) reduced the atheroma area in thoracic aortas of male New Zealand white rabbits fed a 2% cholesterol diet for 6 weeks with balloon denudation of the abdominal aorta being performed at the end of the third week. Intimal hyperplasia, expressed as the intimal/medial area ratio, in the abdominal aortas was significantly inhibited in the both the EGb group (0.61 +/- 0.06) and the probucol group (0.55 +/- 0.03) compared to the C group (0.87 +/- 0.02). In the balloon-injured abdominal aorta, both EGb and probucol significantly reduced IL-1beta mRNA and protein expression and the percentage of proliferating cells. The inhibitory effects of EGb on the intimal response might be attributed to its antioxidant capacity. EGb may have therapeutic potential for the prevention of restenosis after angioplasty.  相似文献   

19.
EGb761 has been suggested to be an antioxidant and free radical scavenger. Excess generation of free radicals, leading to lipid peroxidation (LP), has been proposed to play a role in the damage to striatal neurons induced by 1-methyl-4-phenylpyridinium (MPP+). We investigated the effects of EGb761 pretreatment on MPP+ neurotoxicity. C-57 black mice were pretreated with EGb761 for 17 days at different doses (0.63, 1.25, 2.5, 5 or 10 mg/kg) followed by administration of MPP+, (0.18, 0.36 or 0.72 mg/kg). LP was analyzed in corpus striatum at 30 min, 1 h, 2 h and 24 h after MPP+ administration. Striatal dopamine content was analyzed by HPLC at the highest EGb761 dose at 2 h and 24 h after MPP+ administration. MPP+-induced LP was blocked (100%) by EGb761 (10 mg/kg). Pretreatment with EGb761 partially prevented (32%) the dopamine-depleting effect of MPP+ at 24 h. These results suggest that supplements of EGb761 may be effective at preventing MPP+-induced oxidative stress.  相似文献   

20.
Ginkgo biloba (EGb 761) is a well-defined plant extract that directly scavenges hydroxyl radicals. It is a potent antioxidant that inhibits apoptosis in cultured cells and is effective in treating mild-to-moderate dementia in Alzheimer patients. Apoptosis is an active process of cell destruction and it plays an important role in pathological processes. The aim of this study is to investigate the anti-apoptotic effect of EGb 761 in gossypol-treated human lymphocytes. Pretreatment of lymphocytes with 10 microg/ml EGb 761 for 30 min or 1h decreased the percentage of apoptosis to 17.5% and 20%, respectively. EGb 761 treatment (25-150 microg/ml) decreased the level of apoptosis to a plateau between 8 and 10% of the control values. We conclude that EGb 761 reduces gossypol-induced apoptosis in human lymphocytes.  相似文献   

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