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排序方式: 共有89条查询结果,搜索用时 15 毫秒
1.
传染性法氏囊病病毒cDNA文库的构建   总被引:2,自引:0,他引:2  
陈士友  张兹钧 《病毒学报》1994,10(2):159-163
  相似文献   
2.
陕北黄土高原蒿属植物的分类与分析   总被引:1,自引:0,他引:1  
陕北黄土高原有蒿属植物30种1变种,居该地产种子植物属中所含种数的首位。所产蒿属植物在不同的植被带中梯度变化明显,替代现象显著。在生态类型上,旱生类型从南向北递增,中生类型从南向北递减。在区系组成上可分为6种分布区类型,即:我国特有分布,3种;温带亚洲分布,14种1变种;北温带及中亚分布各4种;旧世界温带分布,3种;东亚分布的2种。可见陕北黄土高原蒿属植物种类丰富,梯度变化明显,旱化现象显著,地理成分复杂,但以温带亚洲分布类型为主,兼有其它成分,属典型的温带性质。  相似文献   
3.
DNA水平上的植物系统学研究方法   总被引:1,自引:0,他引:1  
本文简要总结了近年来在DNA水平上的植物系统学研究方法,着重介绍了限制性长度多态性分析,PCR技术在植物系统学上的应用等这一领域最新的进展,并对分子数据的分析方法及系统树的构建进行了详细讨论。  相似文献   
4.
Phytochemical investigation on the root of Eryngium yuccifolium ‘Kershaw Blue’ resulted in the isolation and identification of two new polyhydroxyoleanene saponins, named eryngioside M and eryngioside N, together with 15 known triterpenoid saponins eryngiosides A-L, 21β-angeloyloxy-3β-[β-d-glucopyranosyl-(1  2)]-[β-d-xylopyranosyl-(1  3)]-β-d-glucuronopyranosyloxyolean-12-ene-15α,16α,22α,28-tetrol, saniculasaponin III, and saniculasaponin II. Their structures were established by extensive spectroscopic and chemical analyses. Eryngioside M and saniculasaponin II showed week cytotoxicity against human non-small cell lung tumor cells (A549) with GI50 values of 37.5 ± 1.59 μM and 35.5 ± 1.11 μM, respectively.  相似文献   
5.
6.
Water soluble protein content (SPC) plays an important role in the functional efficacy of protein in food products. Therefore, for the identification of quantitative trait loci (QTL) associated with SPC, 212 F2:9 lines of the recombinant inbred line (RIL) population derived from the cross of ZDD09454 × Yudou12 were grown along with the parents, in six different environments (location × year) to determine inheritance and map solubility-related genes. A linkage map comprising of 301 SSR markers covering 3,576.81 cM was constructed in the RIL population. Seed SPC was quantified with a macro-Kjeldahl procedure in samples collected over multiple years from three locations (Nantong in 2007 and 2008, Zhengzhou in 2007 and 2008, and Xinxiang in 2008 and 2009). SPC demonstrated transgressive segregation, indicating a complementary genetic structure between the parents. Eleven putative QTL were associated with SPC explaining 4.5–18.2 % of the observed phenotypic variation across the 6 year/location environments. Among these, two QTL (qsp8-4, qsp8-5) near GMENOD2B and Sat_215 showed an association with SPC in multiple environments, suggesting that they were key QTL related to protein solubility. The QTL × environment interaction demonstrated the complex genetic mechanism of SPC. These SPC-associated QTL and linked markers in soybean will provide important information that can be utilized by breeders to improve the functional quality of soybean varieties.  相似文献   
7.
Zhu  Shiyou  Liu  Ying  Zhou  Zhuo  Zhang  Zhiying  Xiao  Xia  Liu  Zhiheng  Chen  Ang  Dong  Xiaojing  Tian  Feng  Chen  Shihua  Xu  Yiyuan  Wang  Chunhui  Li  Qiheng  Niu  Xuran  Pan  Qian  Du  Shuo  Xiao  Junyu  Wang  Jianwei  Wei  Wensheng 《中国科学:生命科学英文版》2022,65(4):701-717
Science China Life Sciences - The outbreak of coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has created a global health crisis. SARS-CoV-2 infects varieties of tissues where the known...  相似文献   
8.
Yang  Meiling  Che  Shiyou  Zhang  Yunxiu  Wang  Hongbin  Wei  Tao  Yan  Guorong  Song  Wenqin  Yu  Weiwei 《Journal of plant research》2019,132(6):825-837
Journal of Plant Research - Drought is an important environmental factor that can severely affect plant growth and reproduction. Although many genes related to drought tolerance have been studied...  相似文献   
9.
Quaternary semiconducting materials based on the kesterite (A2BCX4) mineral structure are the most promising candidates to overtake the current generation of light‐absorbing materials for thin‐film solar cells. Cu2ZnSnS4 (CZTS), Cu2ZnSnSe4 (CZTSe) and their alloy Cu2ZnSn(Se,S)4 consist of abundant, low‐cost and non‐toxic elements, unlike current CdTe and Cu(In,Ga)Se2 based technologies. Zinc‐blende related structures are formed by quaternary compounds, but the complexity associated with the multi‐component system introduces difficulties in material growth, characterization, and application. First‐principles electronic structure simulations, performed over the past five years, that address the structural, electronic, and defect properties of this family of compounds are reviewed. Initial predictions of the bandgaps and crystal structures have recently been verified experimentally. The calculations highlight the role of atomic disorder on the cation sub‐lattice, as well as phase separation of Cu2ZnSnS4 into ZnS and CuSnS3, on the material performance for light‐to‐electricity conversion in photovoltaic devices. Finally, the current grand challenges for materials modeling of thin‐film solar cells are highlighted.  相似文献   
10.
金丝猴颅骨及牙齿的比较形态研究   总被引:1,自引:1,他引:0  
金丝猴(Rhinopithecus roxellanae M.-E.)自从1870年订名以来,对它的研究多限于分类和个体生态习性的观察描述,至于它的形态解剖方面的论述国内几无报道。国外Hooizer(1950)和Swindler(1976)对其牙齿作了简单扼要的描述,前者并在11例川金丝猴头骨中发现一例左侧上颌骨具有P4。这次我们对金丝猴系统的研究过程中,在解剖方面,除了进行各器官系统解剖外,同时还与猕猴、黑叶猴相比较,并对其器官的形态变化和生态生理机能的结合上给以适当注意和解释。  相似文献   
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