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1.
<正> 多年生草本,茎直立,褐黄色或淡紫褐色,仅上部具着生头状花序的分枝,此枝长3—10厘米。茎、枝、叶面微被淡黄色短柔毛或近无毛;叶面具稀疏白色腺点及小凹点,背面具稀疏的蛛丝状薄绒毛;茎下部叶末见;中部为上部叶具短柄或近无柄,叶片卵形或近圆形,长、宽3.5—4.6厘米,(三一)二回羽状全裂,每侧裂片4—6枚,每裂片常再分裂,每侧具  相似文献   
2.
Polygala vauthieri andP. monticola var.brizoides have secondary pollen presentation from a basket-like structure on the style apex. This basket is loaded after the first visit by a bee. Pollen reception, therefore, can precede the issue of pollen. A sticky stigma secretion glues the pollen from the basket under the head of the bee visitor in an exactly predetermined spot on the left side only. This position mostly forms a kind of safe spot, where the bee can not remove the pollen. The exact position on the bee's head is determined by the species specific distance between style tip and nectary in the visited flower. In this way the two sympatric species deposit the pollen 2 mm apart on the visitor and so can avoid hybridization pollination, while being visited by the same group of bees.  相似文献   
3.
A methanolic extract of dried leaves of Polygala japonica Houtt (Polygalaceae) significantly attenuated nitric oxide production in lipopolysaccharide-simulated BV2 microglia. Five anthraquinones chrysophanol (1), emodin (2), aloe-emodin (3), emodin 8-O-β-D-glucopyranoside (4) and trihydroxy anthraquinone (5), and four flavonoids kaempferol (6), chrysoeriol (7), kaempferol 3-gentiobioside (8) and isorhamnetin (9) were isolated from the methanolic extract using bioactivity-guided fractionation. Among them, compounds 14, 6 and 7 showed significant inhibitory effect on lipopolysaccharide-induced nitric oxide production in BV2 microglia at the concentrations ranging from 1.0 to 100.0 μM.  相似文献   
4.
中药远志的研究进展   总被引:2,自引:0,他引:2  
对近年来远志的资源、商品、鉴别、化学成分、药理活性及栽培方面进行了系统的综述,并就商品远志在市场上存在的问题及发展前景进行了探讨。  相似文献   
5.
目的确定人参总皂苷(GTS)和远志总苷(PTG)抗抑郁配伍剂量比例,形成参远苷(SGY)制剂,为研制开发抗抑郁新药提供实验数据。方法采用析因设计方法,GTS和PTG均选取25、50、100 mg/kg三个剂量,按照完全随机的两因素3×3实验设计,得到参远苷的9个不同配比组。C57BL/6J小鼠(用于悬尾实验)和ICR小鼠(用于强迫游泳实验)随机分为对照组、阳性药组(10 mg/kg,帕罗西汀用于悬尾实验;阿米替林用于强迫游泳实验)及参远苷的9个不同配比组,共11组。灌胃给药7 d,观察各组对悬尾或强迫游泳实验小鼠不动时间的影响,并通过空场实验观察参远苷各配比对小鼠自主活动的影响。参远苷与单味GTS、PTG的抗抑郁作用比较实验中,C57BL/6J小鼠(用于悬尾实验)和ICR小鼠(用于强迫游泳实验)随机分为对照组、阳性药组(10 mg/kg,帕罗西汀用于悬尾实验;阿米替林用于强迫游泳实验)、参远苷低中高剂量组(37.5、75、150 mg/kg)、GTS和PTG各四个剂量组(均为18.75、37.5、75、150 mg/kg),共13组。灌胃给药7 d,观察各组对悬尾或强迫游泳实验小鼠不动时间的影响。结果析因设计结果表明,GTS和PTG之间无交互效应。参远苷配比组75 mg/kg(GTS∶PTG为50∶25)及150mg.kg-1(GTS∶PTG为100∶50)显著并稳定缩短悬尾或强迫游泳不动时间(P〈0.05),得出GTS和PTG的剂量配伍比例为2:1。空场实验结果显示,参远苷各配比对小鼠运动总路程无影响。参远苷与单味GTS、PTG抗抑郁作用比较实验结果显示,GTS 75、150 mg/kg缩短悬尾实验小鼠不动时间(P〈0.01,P〈0.05),对强迫游泳实验小鼠不动时间无影响。PTG 18.75、37.5 mg/kg缩短强迫游泳实验小鼠不动时间(P〈0.01,P〈0.05),对悬尾实验小鼠不动时间无影响。参远苷75、150 mg/kg缩短悬尾实验小鼠不动时间(P〈0.05)。同时,参远苷37.5、75 mg/kg缩短强迫游泳实验小鼠不动时间(P〈0.01,P〈0.05)。结论 GTS和PTG以2:1的比例形成的参远苷(SYG)制剂,质量容易控制,作用机制多样,符合抑郁症复杂多样的发病机制,优于单味GTS和PTG,进一步研究之后,有可能成为新型的抗抑郁药物。  相似文献   
6.
H. Wang  J. Gao  J. Kou  D. Zhu  B. Yu 《Phytomedicine》2008,15(5):321-326
Bioassay-guided investigation was performed to identify the active constituents from a methanol extract of Polygala japonica, a folk medicinal plant widely used in China to treat inflammatory diseases. The n-BuOH and EtOAc fractions of the P. japonica methanol extract, which show significant anti-inflammatory activity in in vivo test, were further subjected to column chromatography to afford six triterpene glycosides, marked here as saponins 1–6. All compounds were evaluated for their anti-inflammatory activity in the carageenan-induced mouse paw edema test, and saponins 1, 4 and 5 showed significantly anti-inflammatory effects on both phases of carageenan-induced acute paw edema in mice. Saponin 5 was also found to significantly inhibit the production of inflammatory mediators – nitric oxide (NO) in LPS-stimulated RAW264.7 macrophages, with no obvious effects on macrophage viability.  相似文献   
7.
荆芥中总黄酮的微波提取及含量测定   总被引:9,自引:0,他引:9  
中药荆芥原名假苏 ,始载于《本经》,列入下品 ,为唇形科植物裂叶荆芥 ( Schizonepeta tenuifolia〈 Benth〉Briq)和多裂叶荆芥的茎叶和花穗。民间用于治疗祛风、解表、透疹和止血。近年研究表明荆芥具有解热降温、镇静、镇痛、抗炎、止血、抑制心肌收缩、祛痰平喘、抗氧化等药理作用。目前从荆芥中分离得到的主要化学成分有酚类、酸类、黄酮类化合物 ,穗状花序含有单萜类化合物 ,荆芥挥发油主要含有胡薄荷酮和薄荷酮等化合物 ,具有特殊的香气[1] 。微波技术的应用 ,近年来得到很大发展。微波具有穿透力强、选择性高、加热效率高等特点。微…  相似文献   
8.
从云南中甸产细叶香茶菜 (Isodontenuifolia (W .W .Smith)Kudo)的地上部分分离得到 6个化合物 ,它们的结构通过波谱方法得到鉴定。其中化合物 1和 2为新的对映_贝壳杉烷二萜化合物 ,即细叶香茶菜甲素 (3β ,6α ,15 β_trihydroxy_1α ,7β_diacetoxy_11β ,16 β_epoxy_ent_kaurane) (1)和细叶香茶菜乙素 (1α,6α ,11β_trihydroxy_3β,7β_diacetoxy_ent_kaur_16_en_15_one) (2 )。  相似文献   
9.
Plants that are consumed by herbivores incur a reduction in fitness. Therefore, plants need to prepare to defend against and/or avoid herbivory using ‘resistance’ and/or ‘tolerance’ systems. Phengaris teleius is a specialist herbivore of Sanguisorba tenuifolia. Phengaris teleius lays eggs in the flower buds of S. tenuifolia and the larvae of P. teleius feed on the ovaries and ovules of S. tenuifolia. In order to clarify the extent of herbivory damage by P. teleius and effect on reproduction in S. tenuifolia, we conducted field observations and artificial cutting experiments carried out in the natural habitat where both P. teleius and S. tenuifolia live sympatrically. Phengaris teleius often lays one egg per spike, and about half of the total eggs were laid on the spike that developed at the shoot apex and was largest in size. The fruits were damaged most heavily in the spike in which an egg was laid. However, the number of fruits was almost the same between individuals with no damage and individuals with a feeding damage rate of 40% or less. This showed that compensation would be achieved by increasing the number of fruits in other spikes without damage. On the other hand, because no compensation was detected in the cutting experiments, it was considered that compensation may be induced by biological stimuli produced by P. teleius. These responses may be one of the mechanisms for continuing the interspecific relationship between S. tenuifolia (host plant) and P. teleius (herbivore insect).  相似文献   
10.
Fu J  Zuo L  Yang J  Chen R  Zhang D 《Phytochemistry》2008,69(7):1617-1624
An oligosaccharide polyester, 1-O-(E)-p-coumaroyl-(3-O-benzoyl)-beta-D-fructofuranosyl-(2-->1)-[6-O-(E)-feruloyl-beta-D-glucopyranosyl-(1-->2)]-[6-O-acetyl-beta-D-glucopyranosyl-(1-->3)-(4-O-acetyl)-beta-D-glucopyranosyl-(1-->3)]-4-O-[4-O-alpha-L-rhamnopyranosyl-(E)-p-coumaroyl]-alpha-D-glucopyranoside (polygalajaponicose I), and four triterpenoid saponins, 3beta, 23, 27-trihydroxy-29-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-olean-12-en-28-oic acid (polygalasaponin XLVII), 3-O-beta-D-glucopyranosyl presenegenin 28-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-fucopyranosyl ester (polygalasaponin XLVIII), 3-O-beta-D-glucopyranosyl presenegenin 28-O-beta-D-galactopyranosyl-(1-->5)-beta-D-apiofuranosyl-(1-->4)-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl ester (polygalasaponin XLIX) and 2beta, 27-dihydroxy-3-O-beta-D-glucopyranosyl 11-oxo-olean-12-en-23, 28-dioic acid 28-O-beta-D-galactopyranosyl-(1-->5)-beta-D-apiofuranosyl-(1-->4)-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-fucopyranosyl ester (polygalasaponin L), in addition to five known compounds have been isolated from the roots of Polygala japonica.  相似文献   
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