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11.
毛瑞香酚性成分研究   总被引:4,自引:0,他引:4  
应用色谱技术从毛瑞香根的乙醇提取物中分离和纯化出6个酚性成分,通过光谱方法鉴定其分别为瑞香醇酮(1)、西瑞香素-7-O-葡萄糖苷(2)、芫花苷(3)、瑞香黄烷D1(4)、瑞香黄烷现(5)和紫丁香苷(6)。6个化合物均为首次从该植物中分得。  相似文献   
12.
Transglucosylases in Cichorium intybus converting cichoriin to esculin   总被引:1,自引:0,他引:1  
The heads of Cichorium intybus contain two enzymes concerned in the formation of esculin (esculetin 6-glucoside) from cichoriin (esculetin 7-glucoside). Both enzymes can catalyse two reactions, i.e. hydrolysis (HD) of cichoriin to give esculetin, and transglucosylation (TG) from this glucoside to the liberated aglucone forming esculin. One of them, designated enzyme A, is a high molecular weight protein with predominantly TG activity, and dissociates during isolation into the other enzyme having higher HD activity. Enzyme A shows high substrate specificity and different pH optima in HD and TG reactions, as in the case with the transglucosylase from Daphne odora.  相似文献   
13.
Distribution margins constitute areas particularly prone to random and/or adaptive intraspecific differentiation in plants. This trend may be particularly marked in species discontinuously distributed across mountain ranges, where sharp geographic isolation gradients and habitat boundaries will enhance genetic isolation among populations. In this study, we analysed the level of neutral genetic differentiation among populations of the long-lived shrub Daphne laureola (Thymelaeaceae) across the Baetic Ranges, a glacial refugium and biodiversity hotspot in the western Mediterranean Basin. Within this area, core and marginal populations of D. laureola were compared with regard to their spatial isolation, size, genetic diversity and differentiation. A spatially explicit analysis conducted on the vast majority of the species' known populations in the study area (N = 111) showed that marginal populations (western and eastern) present larger spatial isolation than core populations, but are not smaller. We compared genetic diversity and differentiation between core and marginal populations using a subsample of 15 populations and 225 amplified fragment length polymorphism (AFLP) markers. Core and marginal populations did not differ in genetic diversity, probably because of the occurrence of large populations on the local margins. Western populations were strongly differentiated from the other populations. In addition, spatial and genetic differentiation among populations was larger on the western margin. Eastern populations constituted a genetically homogeneous group closely related to core populations, despite their greater spatial isolation. Results suggest that studies on phenotypic differentiation between core and marginal populations of D. laureola, and presumably other species having discontinuous distributions across the Baetic ranges, should take into account geographical differences in levels of genetic differentiation between the different distribution borders.  相似文献   
14.
Aerial parts of Daphne oleoides Schreber ssp. oleoides (Thymelaeaceae) are used to treat rheumatoid arthritis and lumbago in Turkish folk medicine. In order to evaluate folkloric utilization, in vitro inhibitory effects of the ethyl acetate extract and fractions obtained from this extract on interleukin 1 (IL-1alpha, IL-1beta) and tumour necrosis factor (TNF-alpha) biosynthesis were studied. Through chemical isolation techniques and activity-guided fractionation process, seventeen compounds were isolated and their structures were elucidated (numbered 1-17). Diterpenoids genkwadaphnin (3) and 1,2-dehydrodaphnetoxin (6) and a coumarin derivative daphnetin (9) showed potent inhibitory activity and were found to be the main active ingredients. Furthermore, gnidilatin (4), gnidilatin-20 palmitate (5), genkwadaphnin-20-palmitate (7) and gnidicin-20-palmitate (8), having diterpenoid structure, and eudesmine (12), wikstromol (13) and matairesinol (14), having lignan structure, were determined to possess moderate inhibitory activity and may have a contributory role in the effect of the remedy.  相似文献   
15.
Two new compounds, one flavanol dimer dapholosericol A ( 1 ) and one tigliane diterpene dapholosericin A ( 2 ), together with ten known ones, were isolated from the AcOEt extract of Daphne holosericea (Diels ) Hamaya . Their structures were elucidated by their spectroscopic data analysis. Compounds 1 and 2 showed moderate activities against acetylcholinesterase with inhibition ratio of 36% and 29% at a concentration of 100 μmol/l, respectively.  相似文献   
16.
唐古特瑞香对菜粉蝶幼虫的拒食和胃毒活性   总被引:4,自引:0,他引:4  
用6种极性不同的溶剂对采自青藏高原的唐古特瑞香进行了连续抽提,各种抽提物在100mg干粉/ml的浓度下,均对菜粉蝶5龄幼虫表现出一定的拒食和胃毒作用,发现苯抽提物的生物活性最高,其次是氯仿抽提物。以苯为溶剂对唐古特瑞香的叶、茎皮、茎木质部、根皮、根木质部等5个植株部位进行了抽提,并对抽提物进行了生物活性测定,结果表明,叶的杀虫活性最高。经苯抽提过的残渣再用甲醇抽提,抽提物的生物活性测定结果表明,叶的抽提物具有一定的杀虫活性。从而进一步说明,叶中杀虫活性物质的含量高于其它部位。  相似文献   
17.
The stability of plant reproductive success is dependent on the reproductive system of the plant and the surrounding pollinator assemblages. Here we documented the pollination ecology of a shrub, Daphne miyabeana (Thymelaeaceae), that is unpalatable to deer in two different habitats (open and closed canopy) at a site with severe deer browsing. We found that 31.22 ± 3.07% (mean ± SE) and 9.01 ± 1.71% of the total number of D. miyabeana flowers become fruits in open and closed habitats, respectively. Although spontaneous selfing was possible, the fruit set of that was much lower than the fruit set of an artificial outcrossing treatment. In the closed habitat, the fruit set of the natural pollination was lower than that of artificial outcrossing, whereas in the open habitat the fruit set of those two were similar. In the open habitat, small bees were the major flower visitors, whereas in the closed habitat, ants were the major flower visitors, which did not contribute to pollination. Our findings suggest that D. miyabeana is pollinated by occasional visits of small bees, but it is also self‐compatible and spontaneous selfing is possible. Although its pollination is shaped by abiotic environmental factors, D. miyabeana can reproduce in different habitat conditions. These flexible reproductive systems may be an advantage in coping with the recent environmental change in forest habitats.  相似文献   
18.
从唐古特瑞香(Daphne tangutica Maxim)95%乙醇提取物石油醚部分分离得到14个化合物,通过波谱学方法鉴定为β-谷甾醇(1)、β-胡萝卜苷(2)、2,4-二羟基-3,6-二甲基苯甲酸甲酯(3)、蛇床子素(4)、植物醇(5)、软脂酸(6)、stigmast-5-ene-3β,7α-diol(7)、(-)-lariciresinol(8)、daphnetin(9)、daphnoretin(10)、(-)-丁香树脂醇(11)、( )-medioresinol(12)、daphnelicin(13)和咖啡酸二十二酯(14)。  相似文献   
19.
The Pinus wallichiana, Daphne oleiodes and Bidens chinensis have a long history of being used traditionally for treatment of various types of disorders. Most of the uses have been without any scientific evidence and toxicological assessment. We evaluated the mutagenic and cytotoxic capabilities of various parts of P. wallichiana, D. oleoides and B. chinensis. Ames Salmonella mutagenicity assay determined the mutagenicity activity against TA 98 and TA 100 bacterial strains of Salmonella typhimurium without metabolic activator S9 system. The number of mutant colonies in negative control was considered as limit to determine the mutagenicity effects of every extract. Brine shrimps lethality bioassay was used to determine the cytotoxic capabilities of the selected plants. The P. wallichiana, D. oleiodes and B. chinensis did not showed any mutagenic activity both for frameshift mutation (TA98) and base-pair substitution (TA100) without S9 mixture. The crude methanolic extract of P. wallichiana stem showed moderate cytotoxicity (53.33%) at 1000 μg/ml with LD50 value 599.634. The D. oleoides fruit showed a toxicity of 60% at 1000 μg/ml with LD50 value 367.730. The B. chinensis (whole plant) showed lethality of 63.3% at 1000 μg/ml, with LD50 204.833. The absence of any mutagenic activity of crude extract of the tested plants in both bacteria strains, TA 98 and TA 100 without the S9 mix confirms the safety of these plants to the consumers.  相似文献   
20.
Daphne odora, a blooming shrub, has been traditionally used for various medicinal purposes. However, information on its anti-melanogenic activity and dermal application is limited. In this study, the Daphne odora extract (DOE), with constituents including daphnetin, was used to investigate depigmenting activity and the underlying mechanism of Daphne odora. DOE inhibited in vitro and cellular tyrosinase activity in a dose-dependent manner, and reduced the α-MSH-induced melanin biosynthesis to a control level. The protein expressions of melanin synthesis-related enzymes were also significantly reduced by DOE. Moreover, DOE decreased the phosphorylation of cAMP-response element binding proteins (CREBs) induced by α-MSH in B16F10 cells, while it activated phosphorylated extra-cellular signal-regulated kinases (ERKs) and protein kinase B (AKT) expression. These results suggest that DOE might inhibit the melanogenesis signaling pathways by activating ERK- and AKT-signaling pathways to regulate the expression of CREB and MITF and its downstream pathways. Therefore, DOE could potentially be developed as a depigmenting agent.  相似文献   
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