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1.
为了研究藏药臭蚤草的浩性成分,我们利用各种柱色谱技术,从藏药臭蚤草甲醇提取物的乙酸乙酯萃取相分离到4个化合物,通过1D、2DNMR、MS和HRMS等试验,鉴定为2,4-dihydroxy-6-methyl—ethanone-4-O-β-D—Glc(1),4-(3’-hydroxypropyl)-2,6-dimethoxyphenol-3’-O-β-D—glcoside(2),4-allyl-2-methoxyphenol-1-O-β-gleo—side(3),2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3—O-(6'-O-Ac)-α—L—Rha-(1→2)-β-D—Gle(4),其中化合物1—3为苯丙素苷类化合物,化合物4为蒽醌苷。化合物1—4都是首次从该属植物中分离得到,化合物1为新的苯丙素苷类化合物。  相似文献   

2.
山东汉族成人的Heath-Carter法体型研究   总被引:26,自引:2,他引:24       下载免费PDF全文
应用HeathCarter人体测量法对1001名(男502名,女499名)年龄在20—88岁间的山东省青州和临朐两县市的城乡汉族(以下简称山东汉族)进行了体型评定。结果是:(1)山东汉族男性的平均体型值为44—48—17(城4.6—4.7—1.5,乡4.2—4.8—1.8),属内胚层-中胚层均衡型体型;各年龄组中以内胚层-中胚层均衡体型、偏内胚层的中胚层体型及偏中胚层的内胚层体型为主。女性的平均体型值为5.7—4.2—1.4(城5.8—4.2—1.3,乡5.6—4.2—1.4),属偏中胚层的内胚层体型;各年龄组中以偏中胚层的内胚层体型及内胚层-中胚层均衡体型为主。(2)随着年龄的增长,男(20—44岁)女(20—54岁)性内、中因子值上升,外因子值下降。城乡男女以30岁为体型分界点,表现为30岁前后的体型差异。(3)汉族成年人体型存在显著性性别差异,但无城乡差异。(4)山东汉族男性与蒙古族及加拿大样本人群的平均体型相类似;女性平均体型介于鄂温克族、鄂伦春族、达斡尔族和蒙古族样本人群的平均体型之间。  相似文献   

3.
野桂花化学成分研究   总被引:1,自引:1,他引:0  
从野桂花(Osmanthus yunnanensis)地上部分95%乙醇提取物中首次分离得到18个化合物,应用波谱方法及与已知品对照的手段鉴定它们为:E-阿魏酸二十烷基酯(1)、β-谷甾醇(2)、羽扇豆醇(3)、齐墩果酸(4)、7-oxo-β—sitosterol(5)、乙酰齐墩果酸(6)、(6'-O-palmitoyl)-sitosterol-3-O-β—D—glucoside(7)、rotundioic acid(8)、地榆糖甙II(9)、3β-hydroxy-27-p-(E)-eoumaroyloxyolean-12-en-28-oicacid(10)、3β—laydroxy-27-p-(Z)-coumaroyloxy-olean-12-en-28-oicacid(11)、hycandinic acid ester(12)、绿原酸丁酯(13)、4,5-二咖啡酰奎尼酸丁酯(14)、28-O-β-D—glueopyranosyl rottmdioic acid(16)以及三个半萜类化合物:4,5-dihydroxyprenyl caffeate(15)、4-(6-O-caffeoyl -β-D—glucopyranosyloxy)-5-hydroxyprenyl caffeate(17)、4-β-D—glucopyranosyloxy5-hydroxyprenyl caffeate(18)。  相似文献   

4.
从扁枝石松(Diphasiastrum complanatum)的95%乙醇提取物中分离得到1个新的石松生物碱,经波谱技术鉴定其结构,命名为diphaladine A(1)。同时还分离得到其它9个已知石松生物碱类化合物,其中obsctmmaine A(2),L20,lycoposerramine—K,des—N—methyl—β—obscurine,des-N—methyl-α—obscurine,lycoflexion,和phlegmariurine B等7个化合物均为首次从该植物中分离得到。  相似文献   

5.
水红木中两个新的酚苷成分   总被引:3,自引:0,他引:3  
从水红木(Viburnum cylindricum)植物中分离出2个新化合物,1-phlomglucinyl-(6-methybutyryl)-β-D-glucopyranoside命名为cylindrin A(1),1-[4-(3-hydroxyl-propyl)]-pyrocatechol-(6-methybutyryl)-β-D—glucopyranoside,命名为cylindrin B(2)。以及7个已知化合物tachioside(3),syingic acid-4-β-D-glucopyran oside(4),1-β-D—glucopyanosyloxy-3-methoxy-5-hydroxybenzene(5),4-hydroxy-3-methoxyphenol-1-O-β-D-glucoside(6),4-hydroxy-2,6-dimethoxyphen-1-O-β-D-glucoside(7),phlorogluc inol-1-O-β-D-glucoside(8),1-β-D-glucosyloxy-2-(3-nrethoxy-4-hydroxyphenyl)propane-1,3-diol(9).它们的结构经波谱方法得到鉴定。3—9为首次从该种植物中分离得到。  相似文献   

6.
V EGF 一D 及V EGFR 一3 在乳腺癌淋巴道转移中的作用   总被引:1,自引:1,他引:0       下载免费PDF全文
目的:探讨VEGF-D(血管内皮生长因子-D)及其受体VEGFR-3(血管内皮生长因子受体-3)在乳腺癌淋巴道转移中的作用和意义。方法:采用免疫组化二步法检测90例乳腺癌组织中VEGF—D/VEGFR-3的表达。结果:(1)VECF—D阳性率在淋巴结转移组为82%(41/50)显著高于未转移组37.5%(15/40),(P〈0.01)。VEGFR-3阳性率在淋巴结转移组为84%(42/50)显著高于未转移组42.5%(17/40),(P〈0.05),且VEGF—D与VEGFR-3表达显著相关,(P〈0.05)。(2)VEGF—D表达与年龄、肿瘤大小、病理分型、临床分级、ER、PR无关,与CerbB-2表达显著相关,(P〈0.05)。结论:VEGF—D/VEGFIR-3的表达与乳腺癌淋巴道转移有关,VEGF—D可能促进了乳腺癌淋巴管的生成。  相似文献   

7.
巴戟天挥发性成分研究   总被引:5,自引:0,他引:5  
目的:研究巴戟天中的挥发性成分。方法:利用水蒸气蒸馏法提取巴戟天(Radix morindae offtcinalis)挥发油,用GC—MS进行测定,结合计算机检索技术对分离的化合物进行结构鉴定,应用色谱峰面积归一化法计算各成分的相对百分含量。结果:鉴定出34个化学成分,其中相对百分含量大于2%的分别确定为L-龙脑(Bomeol L)29.28%,α-姜烯(Alpha—Zingiberene)4.88%,2-甲基-6-对甲基苯基-2-庚烯(Ar-Cureumene)4.49%,1-己醇(1-Hexanol)3.40%,β-倍半水芹烯(beta—sesquiphellandrene)3.34%,2-戊基呋喃(2-Amylfuran)3.32%,正壬醛(n—nonanal)2.17%,樟脑(L—camphor)2.07%,β-没药烯(bete—Bisabolene)2.06%。结论:34个挥发性成分均为首次从该植物中得到。  相似文献   

8.
从长穗桑的茎皮中首次分离到9个Diels—Alder型加合物,通过NMR、MS等波谱分析手段分别鉴定为mulberrofuran K(1),mulberrofuran G(2),guangsangon L(3),kuwanon J(4),kuwanonx(5),guangsangonG(6),guangsangon B(7),guangsangon D(8),kuwanon P(9)。化合物1—9进行了抗氧化活性筛选。结果表明,在10^-5M浓度下,化合物1,2,5—7,9对Fe^2+-半胱氨酸诱导的肝微粒体脂质过氧化产生的丙二醛(malondialdehyde,MDA)有抑制作用(抑制率大于50%)。  相似文献   

9.
从滑桃树内生真菌Fusarium sp.(1RGa—1b)的发酵代谢产物中分离得到6个一系列的萘醌类色素化合物,通过波谱分析将其结构鉴定为:3-methylether-fusarubin(1),anhydrofusarubin(2),2-aeetonyl-3-methyl-5-hydro—gen-7-methoxy—naphthazarin(3),2-acetonyl-3-methyl-7-methoxy-8-hydrogen—naphthazarin(4),2-acetonyl-3-methyl-7-methoxy—naphthazarin(5),2-isopropanol-3-methyl-7-methoxy-naphthazafin(6)。利用纸片扩散法对这些化合物的抗细菌及抗真菌活性进行了初步测试,实验结果表明:化合物3和4具有弱的抗金黄色葡萄球菌的活性。  相似文献   

10.
《生物技术世界》2008,(2):88-88
Anti—NTB—A-PE 和CCD226(DNAM-1)-PE IOTest试剂是用于NK(天然杀伤)细胞研究的细胞表面受体的单克隆抗体(mAb),它为疾病研究提供了重要信息。流式细胞仪试剂与FC500系列和Cell Lab Quanta SC系统(加州Beckman Coulter公司)以及其它仪器平台兼容。IOTest Anti—NTB—A-PE与新发现的NK受体家族中的一个成员(称为SLAM,信号转导淋巴细胞激活分子)反应,  相似文献   

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14.
正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

15.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

16.
The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.  相似文献   

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For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

19.
Å. Berg 《Bird Study》2013,60(2):153-165
CapsuleThe amount of forest (at local and landscape scales) and occurrence of residual habitats at the local scale are shown to be the major factors influencing bird community composition in farmland–forest landscapes in central Sweden.

Aims To investigate the importance of local habitat and landscape structure for breeding birds in farmland–forest landscapes in central Sweden.

Methods Breeding birds were censused at 292 points. A detailed habitat mapping was made within 300 m of the points. Within a 300–600 m radius only two major habitats (forests and arable fields) were identified.

Results Cluster analyses of bird communities identified three site types that also differed in habitat composition: (i) partially forested sites in forested landscapes; (ii) heterogeneous sites with residual habitats in mosaic landscapes; and (iii) field-dominated farmland sites in open landscapes. A total of 19 of 25 farmland bird species (restricted to farmland or using both farmland and forest) had the highest abundance in farmland sites with mosaics of forest and farmland, while only six farmland species had the highest abundance in field-dominated sites. The bird community changed from being dominated by farmland species to being dominated by forest species (common in forest landscapes without farmland) at small proportions (10–20%) of forest at the local scale. A major difference in habitat composition between heterogeneous and field-dominated sites was the occurrence of different residual habitats (e.g. shrubby areas and seminatural grasslands). These habitats seemed to influence bird community composition more than land-use, despite covering <10% of the area. Seminatural grasslands were important for bird community composition and species-richness, but grazing seemed to be less important. Among different land-use types, cereal crops were the least preferred fields. Set-asides with tall vegetation and short rotation coppices were positively associated with species-richness of farmland birds.

Conclusion In general, the composition of the landscape was important for bird community composition, although amount and distribution of forests, occurrence of residual habitats and land-use of fields at the local scale had the strongest influence on bird community composition. The possible implications of these patterns for managing farmland–forest landscapes are discussed.  相似文献   

20.
This work describes the isolation and characterization of twenty-nine compounds from the fruits of Rhus typhina L., including eleven flavonoids (1–11), eleven phenols (12–22), two pentacyclic triterpenes (23–24), two organic acids (25–26), one lumichrome (27), one courmarin (28) and one pyrimidine (29) on the basis of their spectroscopic data. Compounds apigenin (1), daidzein (4), orobol (5), 3′, 5, 5′, 7-tetrahydroxyflavanone (6), naringenin (7), butein (8), (-)-catechin (9), quercetin-3-O-α-L-(3″-O-galloyl)-rhamnoside (11), 2-hydroxybenzoic acid (13), 4-hydroxybenzaldehyde (14), vanillin (15), methyl 3,4-dihydroxybenzoate (16), 3,5-dihydroxybenzamide (18), tyrosol (19), caffeic acid (20), 3-(2,4,6-trihydroxyphenyl)-1-(4-hydroxyphenyl)-propan-1-one (21), phlorizin (22), friedelin (23), oleanolic acid (24), 4,4-dimethyl-heptanedioic acid (25), anthranilic acid (26), lumichrome (27), scoparone (28) and uracil (29) have not been recorded before in this plant. This is the first report on the occurrence of compounds 4–7, 9, 11, 13–14, 16, 18–21, 25–29 from the genus Rhus. Moreover, the chemotaxonomic significance of these isolated compounds was also summarized.  相似文献   

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