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An effective procedure for obtaining healthy shoots from nodal segments of Scrophularia yoshimurae is described. Nodal segments cultured on Murashige and Skoog's (MS) basal medium supplemented with 1.0 mg L(-1) benzyladenine (BA) and 0.2 mg L(-1) alpha-naphthaleneacetic acid (NAA) induced multiple shoots in conical flasks that differed in the way they were closed and sealed. Hermitically sealed culture vessels resulted in high hyperhydricity/vitrification. High concentrations of ethylene and CO2 were found to accumulate in these vessels. The hyperhydricity of the shoot cultures could be decreased by progressively ventilating the vessels. Exchange of gases was achieved by removing the Parafilm sealing without affecting sterility. This reduced the hyperhydricity rate and gave a good recovery of vitrified shoots, but resulted in decreased proliferation and a dehydration of proliferating nodal segments and the culture medium. The best number of normal shoots was observed when the parafilm was removed for gaseous exchange after four weeks of culture incubation. The results show that hyperhydricity in shoot cultures of S. yoshimurae could be prevented by sufficient gas exchange during culture.  相似文献   
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玄参多糖成分抗疲劳活性的研究   总被引:3,自引:0,他引:3  
研究了玄参(Scrophularia ningpoensis Hemsl.)多糖类成分对小鼠抗疲劳的药理作用。取雄性(♂)昆明种小鼠,体重22—27g,随机分为空白对照组、香菇多糖阳性对照组、玄参多糖(低、中、高)剂量3组,经灌胃分别给予小鼠生理盐水、香菇多糖及玄参多糖类成分100、200、400mg·kg^-1·d^-1,连续灌胃21d。分别观察小鼠的体重变化情况,负重游泳力竭时间,血清尿素氮、肝糖原和血乳酸的含量。结果表明,玄参多糖类成分可降低运动后小鼠血清尿素氮、血乳酸含量,增加小鼠肝糖原含量,具有抗疲劳的活性作用。  相似文献   
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穗花玄参的环烯醚萜甙   总被引:6,自引:2,他引:4  
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The ethanolic root extract of Scrophularia lepidota, an endemic plant of the Turkish flora, has been investigated for its anti-protozoal and inhibitory effect towards plasmodial enoyl-ACP reductase (FabI), a key enzyme of fatty acid biosynthesis in Plasmodium falciparum. Chromatographic separation of the extract yielded 10 iridoids (1-10), two of which are new, and a known phenylethanoid glycoside (11). The structures of the new compounds were determined as 3,4-dihydro-methylcatalpol (8) and 6-O-[4'-O-trans-(3,4-dimethoxycinnamoyl)-alpha-L-rhamnopyranosyl]aucubin (scrolepidoside, 9) by spectroscopic means. The remaining metabolites were characterized as catalpol (1), 6-O-methylcatalpol (2), aucubin (3), 6-O-alpha-L-rhamnopyranosyl-aucubin (sinuatol, 4), 6-O-beta-D-xylopyranosylaucubin (5), ajugol (6), ajugoside (7), an iridoid-related aglycone (10) and angoroside C (11). Nine isolates were active against Leishmania donovani, with the new compound 9 being most potent (IC50 6.1 microg/ml). Except for 4, all pure compounds revealed some trypanocidal potential against Trypanosoma brucei rhodesiense (IC50 values 29.3-73.0 microg/ml). Only compound 10 showed moderate anti-plasmodial (IC50 40.6 microg/ml) and FabI enzyme inhibitory activity (IC50 100 microg/ml). 10 is the second natural product inhibiting the fatty acid biosynthesis of Plasmodium falciparum.  相似文献   
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In the present study, a protocol was optimized for establishment of callus and cell suspension culture of Scrophularia striata Boiss. as a strategy to obtain an in vitro acteoside producing cell line for the first time. The effects of growth regulators were analyzed to optimize the biomass growth and acteoside production. The stem explant of S. striata was optimum for callus induction. Modified Murashige and Skoog medium supplemented with 0.5 mg/l naphthalene acetic acid + 2.0 mg/l benzyl adenine was the most favorable medium for callus formation with the highest induction rate (100 %), the best callus growth and the highest acteoside content (1.6 μg/g fresh weight). Incompact and rapid growing suspension cells were established in the liquid medium supplemented with 0.5 mg/l naphthalene acetic acid + 2.0 mg/l benzyl adenine. The optimum time of subculture was found to 17–20 days. Acteoside content in the cell suspension was high during exponential growth phase and decreased subsequently at the stationary phase. The maximum content of acteoside (about 14.25 μg/g cell fresh weight) was observed on the 17th day of the cultivation cycle. This study provided an efficient way to further regulation of phenylethanoid glycoside biosynthesis and production of valuable acteoside, a phenylethanoid glycoside, on scale-up in S. striata cell suspension culture.  相似文献   
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Peripheral populations (i.e., those occurring on the edge of a species’ distribution range) can have different origins and genetic characteristics, and they may be critical for the conservation of genetic diversity. We investigated European peripheral populations of Scrophularia arguta, a widespread, annual plant distributed from Arabia to Northwest Africa and Macaronesia. Only two small disjunct population groups of this species occur in Europe, specifically in West‐Central and Southeast Iberia. To disclose the origin of these populations and determine their importance for the conservation of S. arguta genetic diversity, we analyzed DNA sequences from two nuclear and two plastid regions and amplified fragment length polymorphism markers in populations sampled mainly across the western distribution range of the species, and modeled the species distribution under present and late Quaternary conditions. The analyses revealed the presence of three distinct lineages of S. arguta in Europe, as a result of multiple colonization waves at different times in the Quaternary. Two of these lineages, occurring in Southeast Iberia, are the result of more or less recent dispersal from Northwest Africa. In contrast, West‐Central Iberian populations are strongly differentiated from the remaining range of S. arguta and can be considered as peripheral relict populations. Our study is the first to demonstrate the occurrence of at least three colonizations of the European continent from Africa by a native plant species. The diverse histories and genetic makeup of the resulting populations confirm the importance of peripheral populations, and particularly of ancient relict populations, for the conservation of global genetic diversity in widespread species.  相似文献   
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Five phenylpropanoid glycosides isolated from Scrophularia scorodonia L. (Scrophulariaceae), namely angoroside A (1), angoroside C (2), angoroside D (3), acteoside (4) and isoacteoside (5), had been evaluated as potential inhibitors of some macrophage functions involved in the inflammatory process. These compounds have been tested in two experimental systems: ionophore-stimulated mouse peritoneal macrophages and human platelets serve as source of COX-1 and 5-LOX, and mouse peritoneal macrophages stimulated with E. coli LPS are the means of testing for COX-2, NO and TNF-alpha activity. None of compounds assayed had a significant effect on LTC(4)-release from calcium ionophore-stimulated mouse peritoneal macrophages. However, the release of PGE(2) by mouse peritoneal macrophages stimulated with calcium ionophore was inhibited by most of these compounds. In the TXB(2)-release assay, acteoside (4), angoroside A (1) and angoroside C (2) showed a significant effect. These five compounds, except angoroside C (2) significantly inhibited LPS-induced PGE(2), NO and TNF-alpha in a concentration-dependent manner. In LPS-stimulated macrophages, the phenylpropanoid glycoside angoroside C (2) only had activity on NO. These results indicate that the pharmacology of these compounds may participate in the anti-inflammatory effect of Scrophularia scorodonia.  相似文献   
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