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北五味子的果实解剖研究 总被引:2,自引:0,他引:2
采用不同花期的子房与花谢后的果实解剖制片为材料,综合研究结果,明确北五味子的雌花,其离生心皮雌蕊群呈螺旋状着生在圆顶状的花托上。每一个单雌蕊均由鸡冠状柱头与下面膨大的子房构成。花柱缺如。子房有自背缝线上发生的假隔膜隔开,致将子房形成假二室;胚珠倒生乃至弯生,亚边缘胎座(submarginal placenta),受精后发育成旋生聚合浆果(spiral-baccacetum),内含种子1-3(2)枚。种子属双子叶有胚乳种子,胚甚小,约为种子的1/50。 相似文献
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本文描述了寄生于齿叶白绢梅(Exochorda serratifolia S.More)上的叉丝壳属一新种和寄生于北五味子(Schisandra chinensis L.)上的叉丝壳属一中国新记录种,分别是Microsphaera exochordae Q.X.Lu et G.Z.L(?)和M.schizandrae Sawada。 对新种作了中文和拉丁文描述,并附有形态图,同时讨论了与相近种之间的区别。对新记录种进行了中文描述。 相似文献
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Protection of seven dibenzocyclooctadiene lignans from Schisandra chinensis against serum and glucose deprivation injury in SH‐SY5Y cells 下载免费PDF全文
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采用组织块分离方法对五味子根内生真菌进行分离鉴定,并以人参疫病病菌[Phytophthora cactorum(Leb.et Coh.)Schroet.]、人参黑斑病病菌(Alternaria panax Whetz.)为供试病原菌对分离的内生真菌进行了抑菌活性筛选。试验共分离得到74株内生真菌,根据形态特征鉴定出33株,分别隶属于半知菌亚门丛梗孢科的轮枝孢属(Verticillium)、柱隔孢属(Ramularia)和瘤座孢科的镰刀菌属(Fusarium)。通过抑菌试验筛选出5个内生真菌有抑制作用,其中3个内生真菌的发酵产物、乙醇提取液对2种病原菌均有一定的抑菌活性。 相似文献
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The great morphological variation in staminate flowers makes it favorable for its use as the main criteria for infrageneric classification in the genus Schisandra (Schizandra) Michx. Organogenesis of different kinds of the staminate flowers has been observed under SEM. Combined with other currently available studies, the patterns of morphogenesis of the staminate flowers are categorized into three types: the columnar-torus type, the flattened-torus type, and the spherical-torus type. In the columnar-torus type, the torus of the staminate flower is kept columelliform through out the whole ontogenic process of the flower; this type can be further divided into two subtypes—the sphenantheraceous subtype, with the thecae laterally localized on both sides of the connective of the mature stamen, and the grandifloraceous subtype, instead with the thecae located outward or slightly outward. In the flattened-torus type, the torus of the staminate flower gradually becomes swollen and then flattened in the process of floral development, and forms a pentagonal shield together with the enlarged filaments and connectives of the stamen. The torus of the staminate flower in the spherical-torus type becomes carnified and swollen with the stamen growing into the depressions or cavities of the spherical torus. Among the three types, the columnar-torus one might be the primitive type, from which the other two were derived representing two different evolutionary trends respectively. By analyzing the cause of the morphological variation of the staminate flowers, it is suggested that the evolutionary pressure by the insect eating during pollinating enhanced the drastic differentiation of the morphology of the staminate flowers. In some taxa of the genus, in which the Coleoptera acted as the main pollinating agent, the enlargement of the torus of the staminate flower to form a thick flattened shield or a spheroid might be an adaptive fitness to the phylogenetic decreasing in number of the stamen. The primitiveness in stamen morphology of the Schisandra staminate flowers is also discussed, which might agree with the origin antiquity of the genus. The similarity of its heteropolar 3- or 6-aperturate pollen to the 3-aperturate pollen of Eudicots might result from convergent evolution. In addition, main infrageneric classifications of Schisandra and the systematic p 相似文献
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《Free radical research》2013,47(4):483-495
AbstractThis study examined the effects of (?)schisandrin B [(?)Sch B] on MAPK and Nrf2 activation and the subsequent induction of glutathione antioxidant response and cytoprotection against apoptosis in AML12 hepatocytes. Pharmacological tools, such as cytochrome P-450 (CYP) inhibitor, antioxidant, MAPK inhibitors and Nrf2 RNAi, were used to delineate the signalling pathway. (?)Sch B caused a time-dependent activation of MAPK in AML12 cells, particularly the ERK1/2. The MAPK activation was followed by an enhancement in Nrf2 nuclear translocation and the eliciting of a glutathione antioxidant response. Reactive oxygen species arising from a CYP-catalysed reaction with (?)Sch B seemed to be causally related to the activation of MAPK and Nrf2. ERK inhibition by U0126 or Nrf2 suppression by Nrf2 RNAi transfection almost completely abrogated the cytoprotection against menadione-induced apoptosis in (?)Sch B-pre-treated cells. (?)Sch B pre-treatment potentiated the menadione-induced ERK activation, whereas both p38 and JNK activations were suppressed. Under the condition of ERK inhibition, Sch B treatment did not protect against carbon tetrachloride-hepatotoxicity in an in vivo mouse model. In conclusion, (?)Sch B triggers a redox-sensitive ERK/Nrf2 signalling, which then elicits a cellular glutathione antioxidant response and protects against oxidant-induced apoptosis in AML12 cells. 相似文献