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千里光(Senecio scandens Buch.-Ham.ex D.Don)是具有良好开发前景的传统抗菌中草药。为了探讨该物种有性生殖的细胞学机制,实现在物种的遗传育种过程中的指导作用,本研究从细胞学角度观察了千里光配子体发育、配子形成和双受精作用。结果表明,在生殖核分裂为精细胞的过程中,其位置和形态呈现差异,表现为"二态"精细胞;此外,雌配子体的形成符合孢子发育模式,成熟胚囊的形态结构为卵形或梨形,成熟的卵细胞和极核位于珠孔端。根据上述结果可推断,合子在随后二分裂时表现为"基细胞-顶细胞"极性,可能与"二态"精细胞导致的合子细胞质不均一有关。此外,从植物分类学角度,千里光的"二态"精细胞,胚囊极性和合子极性可成为菊科近缘植物分类的细胞学依据。 相似文献
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西藏昆虫考察报告(鞘翅目,金龟子科,丽金龟亚科) 总被引:2,自引:0,他引:2
本篇是中国科学院西藏综合考察队于1960—1961年在西藏采得鞘翅目金龟子科丽金龟亚科标本的鉴定报告。这次采得标本共4属7种,其中新种3种。 相似文献
75.
YING‐PING GAI XUE‐JUAN HAN YI‐QUN LI CHUAN‐ZHONG YUAN YAO‐YAO MO FANG‐YUE GUO QING‐XIN LIU XIAN‐LING JI 《Plant, cell & environment》2014,37(6):1474-1490
To analyse the molecular mechanisms of phytoplasma pathogenicity, the comprehensive metabolomic changes of mulberry leaf and phloem sap in response to phytoplasma infection were examined using gas chromatography‐mass spectrometry. The metabolic profiles obtained revealed that the metabolite compositions of leaf and phloem sap were different, and phytoplasma infection has a greater impact on the metabolome of phloem sap than of leaf. Phytoplasma infection brought about the content changes in various metabolites, such as carbohydrates, amino acids, organic acids, etc. Meanwhile, the results of biochemical analysis showed that the degradation of starch was repressed, and the starch content was increased in the infected leaves. In addition, we found that phytoplasma infection changed the levels of abscisic acid and cytokinin and break phytohormone balance. Interestingly, our data showed that the contents of H2O2 and superoxide were increased in the infected leaves, but not in the phloem saps. Based on the results, the expression levels of the genes involved in the metabolism of some changed metabolites were examined, and the potential molecular mechanisms of these changes were discussed. It can be concluded that both the leaf and phloem saps have a complicated metabolic response to phytoplasma infection, but their response mechanisms were different. 相似文献
76.
NORIHIRO KURAISHI MASAFUMI MATSUI AMIR HAMIDY DAICUS M. BELABUT NORHAYATI AHMAD SOMSAK PANHA AHMAD SUDIN HOI S. YONG JIAN‐PING JIANG HIDETOSHI OTA HO T. THONG KANTO NISHIKAWA 《Zoologica scripta》2013,42(1):54-70
Kuraishi, N., Matsui, M., Hamidy, A., Belabut, D. M., Ahmad, N., Panha, S., Sudin, A., Yong, H. S., Jiang, J.‐P., Ota, H., Thong, H. T. & Nishikawa, K. (2012). Phylogenetic and taxonomic relationships of the Polypedates leucomystax complex (Amphibia). —Zoologica Scripta, 42, 54–70. We investigated the phylogenetic and taxonomic relationships and estimated the history of species diversification and biogeography in the Asian rhacophorid genus Polypedates, focusing on the Polypedates leucomystax complex, whose members are notoriously difficult to classify. We first estimated phylogenetic relationships within the complex using 2005‐bp sequences of the mitochondrial 12S rRNA, tRNAval and 16S rRNA genes with maximum parsimony, maximum likelihood (ML) and Bayesian methods of inference. Polypedates exhibits well‐supported monophyly, with distinct clades for P. otilophus, P. colletti, P. maculatus and the P. leucomystax complex, consisting of P. macrotis, and the Malay (Polypedates sp. from Malay Peninsula), North China (P. braueri), South China (Polypedates cf. mutus 1), Indochina (P. megacephalus), Sunda (P. leucomystax) and Laos (Polypedates cf. mutus 2) clades. In a subsequent phylogenetic analysis of 4696‐bp sequences of the nuclear brain‐derived neurotrophic factor (BDNF), sodium/calcium exchanger 1 (NCX), POMC, Rag‐1, Rhod and Tyr genes using Bayesian methods of inference, all of these clades were recovered. Some clades of the P. leucomystax complex occur sympatrically and show high genetic diversity or morphological and acoustic differences. Similar tendencies were observed between some allopatric clades. Therefore, we consider each of these groups to be distinct specifically. We also estimated absolute divergence times within the genus using Bayesian methods. Divergence in Polypedates began with the divergence of a primarily South Asian Clade from the common ancestor of secondarily South‐East Asia P. maculatus and South‐East Asian members. The divergence between the latter occurred much later. The P. leucomystax complex diverged in the Pliocene, much later than other congeners, and seems to have been greatly affected by human‐related dispersal after the Pleistocene. 相似文献
77.
蛋白激酶Cε亚型 (PKCε)和蛋白酪氨酸激酸Lck均在心肌缺血预适应的信号转导中起着十分重要的作用 .构建PKCε和Lck与绿色荧光蛋白的融合蛋白的真核细胞表达载体 .将其共转染H2 93细胞进行表达 .用荧光显微镜观察到荧光共振能量转移现象 ,从而获得了PKCε和Lck在细胞内发生直接相互作用的证据 相似文献
78.
中国鲎胚胎血细胞生成的初步电镜观察 总被引:3,自引:0,他引:3
人工孵育的鲎胚,以光镜和电镜观察其血细胞发生过程。血细胞包括变形细胞和蓝细胞二系列,均可分为原始、幼稚和成熟三阶段。血细胞生成开始于胚胎的附肢原基形成阶段,变形细胞最早见于胚区,蓝细胞先出现于胚外部分。鲎胚中未发现具备组织结构的造血器官,造血系在结缔组织和血腔中进行。 相似文献
79.
陕西省汉族人群11号染色体10个STR基因座的遗传多态性研究 总被引:2,自引:0,他引:2
为了分析陕西汉族人群中11号染色体上10个短串联重复序列(short tandem repeat, STR)基因座的多态性,采用荧光标记基因扫描方法,对11号染色体上的D11S1760、D11S4102、D11S4116、D11S4207、D11S4162、D11S914、D11S4127、D11S917、D11S4146和D11S915基因座的遗传多态性进行分析。结果显示:D11S1760、D11S4102、D11S4116、D11S4207、D11S4162、D11S914、D11S4127、D11S917、D11S4146和D11S915基因座分别检出17、11、15、11、4、6、7、12、11和13个等位基因,41、18、36、30、8、10、16、30、29和32个基因型,等位基因型符合Hardy-Weinberg平衡(P>0.05)。其杂合度分别为86.72%、67.95%、83.90%、85.96%、58.18%、57.63%、72.60%、72.73%、77.87%和86.40%,表明11号染色体上的这10个STR基因座在汉族人群中有较好的多态性,是理想的遗传标记物。 相似文献
80.