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1.
白粉菌的两个新种   总被引:1,自引:0,他引:1  
本文描述采自四川省的白粉菌的两个新分类单位。它们是寄生于省沽油科野鸦椿上的新种野鸦钩丝壳(Uncinula euscaphidis Xie sp.nov.)和大风子科山梧桐上的新种山桐子钩丝壳(Uncinula idesiae Xie sp.nov.)。省沽油科和大风子科是钩丝壳属白粉菌寄主科的世界新记录。模式标本存放于南充师范学院生物系植物标本室。  相似文献   

2.
野鸦椿属植物归属于省沽油科,主要分布于东亚以及东南亚,我国分布有两个种。该属植物化学成分结构丰富,包括酯类、三萜类、黄酮类等,药理活性广泛,如抗炎、抗肝纤维化、抗氧化等。本文从化学成分及药理活性方面对野鸦椿属植物的研究进行综述,以期为该属植物的深入研究与开发提供文献参考。  相似文献   

3.
归并了金腰属1种和省沽油属1变种,报道2个新异名。  相似文献   

4.
旌节花科与省沽油科花粉形态的研究   总被引:2,自引:2,他引:0  
对旌节花科和省沽油科 4属 13种花粉进行了光镜和扫描电镜的观察 ,其中有些种是第一次观察或报道。这两个科的花粉为近球形到球形 ,3孔沟 (省沽油科银鹊树属TapisciaOliv花粉除外 ,为 3沟 )。它们的花粉大小和外壁纹饰有一定差异。旌节花科花粉相对较小 ,一般为 18~ 2 8 2× 17 5~ 2 6 5 μm ,外壁表面为穴状纹饰。省沽油科花粉较大 ,为 2 8~ 4 0× 2 8 5~4 0 5 μm (银鹊树属花粉只有 13 5~ 17 9× 12 5~ 18μm) ,外壁表面为细网状纹饰。这两个科的花粉特征在某种程度上具有一定的相似性 ,故就孢粉学而言它们具有颇为密切的关系  相似文献   

5.
用气相色谱-质谱联用(GC-MS)方法对超临界CO2萃取出的省沽油种子油中角鲨烯和维生素E进行分析。省沽油种子油的萃取采用超临界CO2萃取技术,压力25MPa,温度50℃,时间2h;种子油用GC-MS方法分析,以正三十二烷为内标,用内标标准曲线法同时测定省沽油种子油中角鲨烯和维生素E的含量。结果表明:超临界CO2萃取种子油的收率为28.83%;所建立的定量分析方法平均回收率在96.0%~99.0%之间,相对标准偏差小于2.8%,线性相关系数大于0.999,方法检测限在2.0~2.5mg/L之间;省沽油种子油中含角鲨烯4.65%,维生素E1.58%。  相似文献   

6.
选取生长习性、植物形态、木材解剖、花的形态结构、花粉特征以及胚胎学和染色体数目等共72个性状,采用最大简约法(Maximum Parsimony,MP)对旌节花科及其相关类群五桠果科、猕猴桃科、山茶科、金莲木科和省沽油科等进行分支分析。并用靴带检验法(Bootstrap)计算内部分支的支持率。分支图表明,旌节花科与省沽油科组成姊妹群,靴带支持率为79%,表明旌节花科与省沽油科具有最为密切的关系。旌节花科与猕猴桃科的关系次之,旌节花科和省沽油科与猕猴桃科关系的靴带支持率为58%。然后是山茶科。而旌节花科与金莲木科和五桠果科的关系则依次疏远。这与我们在孢粉学和胚胎学研究中所得的结论在某些方面是基本一致的。与Nandi等人用形态学数据和分子数据分析得到的结论也比较吻合,他们的结论也认为旌节花科与省沽油科具有比较密切的关系。只是他们把五桠果科和金莲木科摆在更近的位置,而山茶科和猕猴桃科则放在较疏远的位置上。  相似文献   

7.
虽然在历史植物地理学文献中常见的有5种区系成分;地理成分、发生成分、迁移成分、历史成分和生态成分,但由于缺乏古地理、古气候和古植物资料,当前要全面分析一个区系中所有5种成分是不可能的。本文是基于省沽油科、刺参科和忍冬科植物研究的结果,企图分析东亚植物区系的历史成分,从一个侧面看到它的演变过程。除去本地产生的鬼吹箫属和六道木属之外,凡以上3科在东亚有分布的属,按其历史成分,可归为3类;北方第三纪成分——忍冬属、猬实属、锦带花属和莛子?属;提特斯第三纪成分-刺参属、刺续断属、蓟叶参属、野鸦椿属、毛核木属、糯米条属、北极花属、双盾木属和七子花属;北热带成分- 山香圆属、省沽油属和瘿椒树属。本文所指北方第三纪植物群和提特斯第三纪植物群是采用Takhtajan的概念,而北热带植物群是采用Wolfe的概念。这3种成分意味着东亚被子植物区系在演变过程中有3个第三纪源头。本文作者还认为中新世在东亚植物区系中似可作为区分被子植物“新特有属”和“古特有属”的一个分界期。大凡起源于中新世以前的属可视为“古特有属”,起源于中新世及其后的可归为“新特有属”。这个假设是基于下列理由:(1)东亚植物区系的主体部分形成于早中新世;(2)在中新世,植物长距离的传播基本停止,现在植物区系区划中的“区”(region),其迅速分化和丰富其多样性主要依靠本地产生的特有类群;(3)从中新世至上新世,喜马拉雅运动加剧,不仅改变了我国的地形,而且全面地影响了我国的自然地理环境。  相似文献   

8.
省沽油群体遗传多样性的AFLP分析   总被引:2,自引:0,他引:2  
利用4对AFLP引物对来自安徽石台、湖北大悟和河南桐柏的3个省沽油群体进行遗传多样性分析,共扩增出489条带,其中多态性条带460条,多态性百分比为93.99%。不同群体Nei’s基因多样性指数(H)和Shannon’s信息指数(I)变化范围分别为0.1920~0.2046和0.2937~0.3151,其中湖北大悟群体遗传多样性最高。物种水平和种群水平的H分别为0.2190和0.1964,群体内变异占总变异的89.68%,表明省沽油遗传变异主要存在于各群体内部。3个群体的平均遗传距离为0.0292,UPGMA聚类分析结果说明省沽油各群体间亲缘关系较近并和地域具有相关性。建议省沽油的遗传资源保护应以种内遗传多样性的保护为主。  相似文献   

9.
省沽油科叶解剖结构的分类学意义   总被引:1,自引:0,他引:1  
丁士友  于兆英 《植物研究》1992,12(2):177-184
本文对国产省沽油科 Staphyleaceae 4属植物叶的解剖结构进行了详细的比较研究。结果表明, 叶解剖结构特征在属间的区别较明显, 特别是瘿椒树属 Tapiscia 有着几乎与其他三属截然不同的独特性状。根据已有的孢粉学, 花、节及木材的解剖等方面的资料, 我们支持Тахтаджян(1987)将瘿椒树亚科分出而建立瘿椒树科 Tapisciaceae 的观点。瘿椒树属为我国特有属, 根据我们对采自不同产地的材料观察, 居群间的差异很小, 其可能仍为一单种属。  相似文献   

10.
以中文版《中国植物志·第46卷》中收载的省沽油科植物分类群为基础,通过与英文修订版“Flora of China(Vol.11)”中相应分类群进行比较,报道了2部著作中植物分类群的学名和分类位置的变动及收载种类的增减情况,以资正确鉴定和编目应用。  相似文献   

11.
12.
Gundara JS  Robinson BG  Sidhu SB 《Autophagy》2011,7(12):1553-1554
MicroRNAs (miRs) are increasingly important diagnostic and prognostic markers in cancer but have not been defined in medullary thyroid carcinoma (MTC). MiR microarray profiling was performed on 19 primary MTC tumors, validated with qPCR in 45 cases and correlated with clinical outcomes. MiRs-183 and 375 were overexpressed and miR-9* underexpressed in sporadic vs. hereditary MTC (SMTC; HMTC). MiR-183 and 375 overexpression predicted lateral nodal metastases, residual disease, distant metastases and mortality. MiR-183 knockdown in an MTC cell line (TT cells) reduced cellular proliferation in association with elevated LC3B expression. This is suggestive of increased autophagic flux and potential cell death via autophagy induction. MiRs may subsequently be shown to serve as efficacious therapeutic strategies in MTC with a mechanism based upon autophagy.  相似文献   

13.
Simpson L 《Protist》2006,157(4):2404-362
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14.
15.
Chromatin is a highly complex mixture of proteins and DNA that is involved in the regulation and coordination of gene expression within the eukaryotic nucleus. Changes in chromatin structure can convey heritable changes of gene activity in response to external stimuli without altering the primary DNA sequence. This epigenetic inheritance of particular traits very likely plays a major role during evolutionary processes. It is however, still ill-defined how this non DNA-mediated inheritance is accomplished at a molecular level. The advent of new methods to systematically study genome-wide changes in chromatin condensation, DNA methylation levels, RNA synthesis and the association of specific proteins or protein modifications now allows a thorough investigation of changes in chromatin structure and function in response to environmental alterations. We would like to review some of these global approaches and to introduce the term "chromatomics" for the systematic analysis of the DNA, RNA and protein content of the genetic material in the eukaryotic nucleus.  相似文献   

16.
The distribution in the human genome of the largest family of mobile elements, the Alu sequences, has been investigated for the past 30 years, and the vast majority of Alu sequences were shown to have the highest density in GC-rich isochores. Ten years ago, it was discovered, however, that the small "youngest" (most recently transposed) Alu families had a strikingly different distribution compared with the "old" families. This raised the question as to how this change took place in evolution. We solved what was considered to be a "mystery" by 1) revisiting our previous results on the integration and stability of retroviral sequences, and 2) assessing the densities of acceptor sites TTTT/AA in isochore families. We could conclude 1) that the open state of chromatin structure plays a crucial role in allowing not only the initial integration of retroviral sequences but also that of the youngest Alu sequences, and 2) that the distribution of old Alus can be explained as due to Alu sequences being unstable in the GC-poor isochores but stable in the compositionally matching GC-rich isochores, again in line with what happens in the case of retroviral sequences.  相似文献   

17.
Both qualitative and quantitative comparative studies of "dark" and "light" pinealocytes of the porcine pineal gland have been carried out. These cells differ from each other in their electronic density of cytoplasm, shape of nucleus, the structure of membrane bound dense bodies and the number of microtubules and smooth endoplasmic reticulum. The membrane bound dense bodies--characteristic structures of pig pinealocytes as well dense core vesicles occur in both types of cells. The relative volume of the majority of the cells' organellae apart from the Golgi apparatus, also do not show any significant difference. The results obtained support a functional basis for pinealocyte differentiation in the porcine pineal gland.  相似文献   

18.
19.
If one looks back on the history of American research ethics, a bold pattern emerges. Since World War II, about every twenty years or so a breach of the social contract between investigators and human research subjects galvanizes public and professional interest in the ethical foundations and oversight mechanisms governing research with humans.  相似文献   

20.
Data on cytological peculiarities of dorsomedial nucleus neurones of the amygdala complex, one of the main zones of sexual dimorphism, in dynamics of estrous cycle are reported. We show that structural and functional characteristics of "dark" and "pale" cells may change depending on the concentrations of gonadal steroids in estrous and metaestrous stages. This specifies the previous hypothesis about mutual reorganization of these cells.  相似文献   

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