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1.
The liver leaf, Hepatica nobilis (Ranunculaceae), is a perennial forest understory herb with specific habitat requirements, which occurs on calcareous soils in beech and oak forests. In Bavaria it can be found, therefore, only in four geographic regions, which are Franconia, the Franconian-Swabian Jura, the prealpine transitions region and the prealpine moraine belt with the Alps. In German forestry, provenance delineations are used since 1987. Similarly for herbs seed provenances and production areas are applied in commercial seed production and restoration. In this study we analyzed whether the genetic variation of H. nobilis reflects the geographic distribution of the species in Bavaria or the provenance delineations used for seed production.We applied AFLPs to study genetic variation within and between 24 populations of H. nobilis.Our analysis revealed high levels of genetic variation within and moderate variation between populations. Variation between seed production areas and seed provenances was low and comparable to the variation between geographic regions. Genetic variation within populations or rare fragments did not differ between production areas, provenances or geographic regions. A significant positive relation of genetic and geographic distances was present within 100 km.Pollination and seed dispersal seem mainly to happen within populations of the myrmecochorous H. nobilis, whereas long-distance dispersal is presumably occasional and random. Our study supports the relevance of dispersal traits for seed collections used in conservation. The protection of historically old beech and oak forests is exceedingly important to preserve the genetic variation of H. nobilis in Bavaria. 相似文献
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Two new compounds, derriscoumaronochromone (1) and cis-3,4′-dihydroxy- 5,7-dimethoxyflavan (2), as well as trans-4'-O-methylcatechin (3) were isolated from Derris laxiflora, The structures of these compounds were determined by analysis of their spectroscopic data. 相似文献
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We developed eight polymorphic microsatellite simple sequence repeat (SSR) loci from genomic DNA of a clonal perennial herb, Convallaria keiskei, using a dual‐suppression‐polymerase chain reaction (PCR) technique and an improved technique. These markers with four to 10 alleles per locus identified 29 genotypes in 82 samples collected from a population in Hokkaido, Japan. The observed and expected heterozygosities ranged from 0.241 to 0.862 and from 0.639 to 0.825, respectively. These SSR markers will be available to identify genets and evaluate genetic diversity of C. keiskei. 相似文献
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The fruit of Crataegus dahurica Koehne was used to treat the disease of infantile indigestion and dyspepsia as an ethnic medicine and food. As a continuous work on finding the active constituents from the edible herbs, four new biphenyl derivatives ( 1 – 4 ), together with two known compounds ( 5 and 6 ), were obtained from the petroleum ether fraction of the fruits of C. dahurica. Their structures were determined by the extensive 1D and 2D NMR spectra and HR‐MS spectrometry. Furthermore, the anti‐inflammatory activities of all the isolated compounds were investigated, in which compound 4 showed moderately inhibitory effects on NO production in RAW264.7 cells without inducing cytotoxicity. 相似文献
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Zhenghua Gong Jiayu Lin Jie Zheng Liya Wei Li Liu Yanzhong Peng Weicheng Liang Guoxin Hu 《Journal of cellular biochemistry》2020,121(2):1431-1440
It is well characterized that activated hepatic stellate cells (HSCs) exert critical functions in accelerating the progression of liver fibrosis. Previous studies have indicated that Dahuang Zhechong pill (DHZCP), a traditional Chinese herbal medicine, is capable of inactivating HSCs and thus attenuate the formation of liver fibrosis in rats. However, pharmacological mechanisms of DHZCP in alleviating liver fibrosis remain unclear. This study aims to investigate the antifibrotic role of DHZCP through inhibiting the phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt) pathway. DHZCP was found to significantly suppresses extracellular matrix formation and immune cell infiltration, thus alleviating liver fibrosis symptoms in the in vivo model. Moreover, DHZCP reduced serum levels of transforming growth factor β1 and tumor necrosis factor-α in rats with liver fibrosis. DHZCP treatment remarkably downregulated protein levels of PI3K and phosphorylated Akt, as well as fibrosis markers. In vitro experiments further demonstrated that DHZCP markedly suppressed HSCs proliferation by downregulating PI3K/Akt, which exerted a synergistic effect with the PI3K inhibitor LY294002. To sum up, our results confirmed that DHZCP exerted an antifibrotic effect in the animal model through inactivating the PI3K/Akt pathway, thus protecting rats from liver injury. 相似文献
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目的应用黄瓜香等中草药作为微生态调节剂治疗青少年寻常型痤疮。方法通过比较治疗前后痤疮患者面部皮肤痤疮丙酸杆菌和表皮葡萄球菌数量以及面部皮疹的数量来判断黄瓜香等中草药治疗痤疮的疗效。结果黄瓜香抑制了痤疮丙酸杆菌和表皮葡萄球菌生长(P〈0.05);减少了皮疹数量(P〈0.05),使皮疹不再出现。结论黄瓜香等能够治疗青少年寻常型痤疮。 相似文献
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Saswati Chakraborti Sangram Sinha Rabindra K. Sinha 《In vitro cellular & developmental biology. Plant》2006,42(5):394-398
Summary This study reports an efficient and direct shoot bud differentiation and multiple shoot induction from nodal segments of underground
stoloniferous rhizomes of Houttuynia cordata Thumb. The frequency of shoot bud regeneration was influenced by the type of cytokinin and concentrations. Among the various
concentrations used, benzylaminopurine (BAP, 17.74 μM) or kinetin (Kn, 18.58 μM) was found to be most effective for rapid and maximum shoot but differentiation. The number of shoots per explant was higher
(20.00±2.61) on Murashige and Skoog (MS) medium supplemented with Kn (18.58 μM) compared to BAP and 6-γ-γ-(dimethyl-allylamino)-purine (2iP) during initial 40-d-old culture. Subsequent shoot
differentiation and multiplication were achieved in MS medium containing 9.29 μM Kn and 15% (v/v) coconut milk. Elongation and growth of multiple shoots were also obtained on MS medium containing either
2.32 μM Kn or 2.46 μM 2iP alone. The rate of shoot multiplication during subcultures declined with an increase in the size of proliferating shoot
cluster. Reducing shoot cluster size to three to four shoots and subculturing together in shoot multiplication medium resulted
in a better shoot multiplication and growth, which could be maintained for 2 yr. The elongated shoots (>20 mm) were successfully
rooted on MS medium supplemented with 19.60 μM indole-3-butyric acid. Regenerated plants were successfully established in soil and were found to be healthy and uniform.
The protocol reported in this study can be used for conservation and utilization of elite clone of H. cordata. 相似文献