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991.
Qi Zhou 《基因组蛋白质组与生物信息学报(英文版)》2013,11(5):257-258
<正>Conversion of cell fate is not only an essential biological question,but also has great clinical values.In early 1950s,cellular reprogramming was frst achieved using the technique of somatic cell nuclear transfer(SCNT),which transferred the nuclear of somatic cells into an enucleated oocyte,thus converted the mature somatic cells into pluripotent state.Using this technique 相似文献
992.
周永力 《植物遗传资源学报》2013,14(3):390-394
采用菲律宾10个代表菌株和我国V型菌代表菌株在植株的分蘖初期和孕穗期人工接种,鉴定和评价近年选育的26个“绿色超级稻”品种(系)对白叶枯病的抗性。结果表明多数品种在分蘖初期和孕穗期对病菌的抗感水平相同,少数品种接种在孕穗期接种部分菌株后的病斑长度小于苗期。此外,新黄占、华201S-1 和XF10450在分蘖初期和孕穗期接种10个菌株后的病斑长度均小于5cm,具有高度的广谱抗性;其它品种对不同菌株的抗性水平不同,黄华占、旱优113、新两优3411和天优145对4-5个菌株表现抗病,旱优75、旱优715和009067对测试的10-11个菌株高度感病;其它品系对所有菌株表现中度感病或感病。
关键词:水稻品种;白叶枯病;抗性 相似文献
993.
本研究以不同来源、不同类型的46个烟草品种为试验材料,进行抗烟草普通花叶病(TMV)特性的田间鉴定和分子鉴定,为筛选抗病烟草种质奠定基础。结果表明,22个品种的烟草抗TMV特性田间鉴定结果与前人鉴定结果基本相同,从24个前人未鉴定的烟草品种中初步筛选出14个中抗品种,8个中感品种和2个感病品种;通过抗TMV基因(CN)的特异引物进行扩增,36个烟草品种的基因组DNA具有特异性片段;通过分子鉴定和田间鉴定的结果比较,62.9%的具有CN或其同源基因的烟草品种田间鉴定表现为中抗或高抗,83.3%的具有CN或其同源基因的选育烟草品种田间鉴定表现为中抗或高抗;结合两种方法,初步确定了3个中感品种和11个中抗品种。 相似文献
994.
Wei‐Guang Wang Zhao‐Yuan Wu Rui Chen Hai‐Zhou Li Hong‐Mei Li Yuan‐Dan Li Rong‐Tao Li Huai‐Rong Luo 《化学与生物多样性》2013,10(6):1061-1071
Four highly acylated diterpenoids, designated as pierisformotoxins A–D ( 1 – 4 , resp.), along with 26 known compounds, were isolated from the flowers of Pieris formosa. Among them, pierisformotoxins A and B ( 1 and 2 , resp.) were new highly acylated grayanane diterpenoids, of which the five‐membered ring A has undergone an oxidative cleavage between C(3) and C(4), followed by lactonization, to give rise to a five‐membered lactone ring between C(3) and C(5), differing from the previously reported grayanane diterpenoids with a 5/7/6/5 ring system. Results of the cAMP‐regulation‐activity assay showed that pierisformotoxin C ( 3 ) at 10 μM (inhibitory ratio (IR): 10.1%) or 2 μM (9.8%), and pierisformotoxin B ( 2 ) at 50 μM (13.9%) significantly decreased the cAMP level in N1E‐115 neuroblastoma cells (p<0.05). 相似文献
995.
996.
Yang Bai Zhong-Jun Zhou Jia-Jun Wang Ying Li Di Wu Wei Chen Zhi-Ru Li Chia-Chung Sun 《Journal of molecular modeling》2013,19(9):3983-3991
How to generate a non-zero first hyperpolarizability for a centrosymmetric molecule is a challenging question. In this paper, an external (pump) electric field is used to make a centrosymmetric benzene molecule generate a non-zero value of the electric field induced first hyperpolarizability (β F ). This comes from the centrosymmetry breaking of electron cloud. Two interesting rules are exhibited. (1) β F is anisotropic for different directional fields (F i, i?=?X, Y, Z). (2) The field dependence of β F is a non-monotonic function, and an optimum external electric field causes the maximum value of β F . The largest first hyperpolarizability β F reaches the considerable level of 3.9?×?105 a.u. under F Y?=?330?×?10?4 a.u. for benzene. The external electric field effects on non-centrosymmetric edge-modified graphene ribbon H2N-(3,3)ZGNR-NO2 was also studied in this work. The first hyperpolarizability reaches as much as 2.1?×?107 a.u. under F X?=?600?×?10?4 a.u. for H2N-(3,3)ZGNR-NO2. We show that the external electric field can not only create a non-zero first hyperpolarizability for centrosymmetric molecule, but also remarkably enhance the first hyperpolarizability for a non-centrosymmetric molecule. 相似文献
997.
In the present paper, a new type of Lewis acid–base complex BX3???Li@Calix[4]pyrrole (X = H and F) was designed and assembled based on electride molecule Li@calix[4]pyrrole (as a Lewis base) and the electron deficient molecule BX3 (as a Lewis acid) by employing quantum mechanical calculation. The new Lewis acid–base complex offers an interesting push-excess electron-pull (P-e-P) framework to enhance the stability and nonlinear optical (NLO) response. To measure the nonlinear optical response, static first hyperpolarizabilities (β 0) are exhibited. Significantly, point-face assembled Lewis acid–base complex BF3???Li@Calix[4]pyrrole (II) has considerable first hyperpolarizabilities (β 0) value (1.4?×?106 a.u.), which is about 117 times larger than reported 11,721 a.u. of electride Li@Calix[4]pyrrole. Further investigations show that, in BX3???Li@Calix[4]pyrrole with P-e-P framework, a strong charge-transfer transition from the ground state to the excited state contributes to the enhancement of first hyperpolarizability. Theory calculation of enthalpies of reaction (ΔrH0) at 298 K demonstrates that it is feasible to synthetize the complexes BX3???Li@Calix[4]pyrrole. In addition, compared with Li@Calix[4]pyrrole, the vertical ionization potential (VIP) and HOMO–LUMO gap of BX3???Li@Calix[4]pyrrole have obviously increased, due to the introduction of the Lewis acid molecule BX3. The novel Lewis acid–base NLO complex possesses not only a large nonlinear optical response but also higher stability. Figure
A novel Lewis acid–base complex is first proposed by the combination of usual Lewis acid and an electride. It offers an interesting push-excess electron-pull framework to enhance the stability and nonlinear optical response. 相似文献
998.
Min Cen Jian Fen Fan Dong Yan Liu Xue Zeng Song Jian Liu Wei Qun Zhou He Ming Xiao 《Journal of molecular modeling》2013,19(2):601-611
Molecular dynamic (MD) simulations have been performed to study the behaviors of ten kinds of cyclo-hexa-peptides (CHPs) composed of amino acids with the diverse hydrophilic/hydrophobic side chains at the water/cyclohexane interface. All the CHPs take the “horse-saddle” conformations at the interface and the hydrophilicity/hydrophobicity of the side chains influences the backbones’ structural deformations. The orientations and distributions of the CHPs at the interface and the differences of interaction energies (ΔΔE) between the CHPs and the two liquid phases have been determined. RDF analysis shows that the H-bonds were formed between the OC atoms of the CHPs’ backbones and Hw atoms of water molecules. N atoms of the CHPs’ backbones formed the H-bonds or van der Waals interactions with the water solvent. It was found that there is a parallel relationship between ΔΔE and the lateral diffusion coefficients (D xy ) of the CHPs at the interface. The movements of water molecules close to the interface are confined to some extent, indicating that the dynamics of the CHPs and interfacial water molecules are strongly coupled. Figure
Scheme of the ten kinds of CHPs formed by even alternating D- and L- amino acids with the different hydrophilic/hydrophobic side chains. The letters in the parentheses stand for the abbreviations of the composed amino acids in the CHPs 相似文献
999.
Adnan Ali Khan Choudhury James V. Conlan Vanessa Nadine Racloz Simon Andrew Reid Stuart D. Blacksell Stanley G. Fenwick Andrew R. C. Thompson Boualam Khamlome Khamphouth Vongxay Maxine Whittaker 《EcoHealth》2013,10(1):54-62
The parasitic zoonoses human cysticercosis (Taenia solium), taeniasis (other Taenia species) and trichinellosis (Trichinella species) are endemic in the Lao People’s Democratic Republic (Lao PDR). This study was designed to quantify the economic burden pig-associated zoonotic disease pose in Lao PDR. In particular, the analysis included estimation of the losses in the pork industry as well as losses due to human illness and lost productivity. A Markov-probability based decision-tree model was chosen to form the basis of the calculations to estimate the economic and public health impacts of taeniasis, trichinellosis and cysticercosis. Two different decision trees were run simultaneously on the model’s human cohort. A third decision tree simulated the potential impacts on pig production. The human capital method was used to estimate productivity loss. The results found varied significantly depending on the rate of hospitalisation due to neurocysticerosis. This study is the first systematic estimate of the economic impact of pig-associated zoonotic diseases in Lao PDR that demonstrates the significance of the diseases in that country. 相似文献
1000.
Xiao‐Bin Li Fei Xie Shan‐Shan Liu Ying Li Jin‐Chuan Zhou Yong‐Qing Liu Hui‐Qing Yuan Hong‐Xiang Lou 《化学与生物多样性》2013,10(7):1193-1201
Bioactivity‐guided fractionation of the cytotoxic extract of Aspergillus niger, an endophytic fungus from the Chinese liverwort Heteroscyphus tener (Steph .) Schiffn ., afforded five new naphtho‐γ‐pyrones, rubrofusarin‐6‐O‐α‐D ‐ribofuranoside ( 1 ), (R)‐10‐(3‐succinimidyl)‐TMC‐256A1 ( 2 ), asperpyrone E ( 3 ), isoaurasperone A ( 4 ), and isoaurasperone F ( 5 ), as well as four known ones, dianhydroaurasperone C ( 6 ), aurasperone D ( 7 ), asperpyrone D ( 8 ), and asperpyrone A ( 9 ), together with a cytotoxic cyclic pentapeptide, malformin A1 ( 10 ). Their structures were determined by extensive spectroscopic analysis. The absolute configurations of dimeric naphtho‐γ‐pyrones 3 – 9 were also determined by analysis of their respective CD spectra. 相似文献