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971.
Hong Cheng Ming-Xu Fang Xia-Wei Jiang Min Wu Xu-Fen Zhu Gang Zheng Zhi-Jian Yang 《Standards in genomic sciences》2013,8(3):491-499
The genus Amphibacillus was established in 1990, and seven additional species were described in the past two decades. Amphibacillus jilinensis Y1T is a facultatively anaerobic and alkaliphilic bacterium isolated from a soda lake in China. Here we describe the structural and genetic features of the draft genome about the type strain Y1T (3,831,075 bp, with a G+C content of 37.27%). This is the first genome report of the Amphibacillus genus. 相似文献
972.
目的:在前人研究基础上进一步调查和研究类风湿关节炎(RA)患者药物治疗的规范化状况。方法:对湘潭市中心医院2012年3月至12月门诊就诊的120例风湿关节炎患者进行问卷调查。内容包括患者个人资料、就诊及确诊时间、科室,随诊时间间隔以及改善病情抗风湿药(DMARDs)的应用情况。结果:类风湿关节炎药物治疗不规范,甲氨蝶呤是患者应用最多的DMARDs,占60%,其次为来氟米特(30%)、柳氮磺吡啶(5%)及羟氯喹(5%)。结论:51%以上的RA病人DMARDs治疗不规范,尤其是在县级基层医院。类风湿性疾病的规范治疗需要从早期诊断治疗,优化联合用药,个性化治疗,定期跟踪疗效等方面来规范。 相似文献
973.
对新疆东天山地区6个宽刺蔷薇(Rosa platyacantha)居群进行叶片、花序、果实、种子等11个表型性状的遗传多样性分析,结果表明:宽刺蔷薇各表型性状无论在居群间还是在居群内均表现出显著或极显著差异,存在丰富的表型多样性。6个居群11个性状的平均表型分化系数为27.50%,表明居群内多样性较居群间多样性更为丰富。各表型性状平均变异系数为16.51%,离散程度相对较低。对表型性状进行的变异系数多重比较和主成分分析均显示,果实相关性状的变异是造成宽刺蔷薇表型变异的主要来源。性状相关性分析进一步发现,生殖生长与前期的营养生长并无明显相关关系。聚类分析结果表明,6个宽刺蔷薇居群的表型性状并没有严格依地理距离聚类,而是受到遗传因素与环境条件特别是海拔因子的共同影响。 相似文献
974.
选用华南地区广泛应用的8个杂交稻不育系与10个恢复系,按NCII设计配制两套不完全双列杂交组合61个,通过在湛江的两年种植试验,结合62对与产量性状QTL连锁SSR标记,对18个亲本的产量配合力进行综合评价和标记位点鉴定。结果表明:供试亲本间一般配合力存在较大差异,其中不育系珍汕97A、万金A和恢复系直龙、广恢3550的一般配合力相对较高;两套组合共检测出36个与亲本产量配合力显著相关的标记位点,其中RM1、RM216、RM231和RM542为两套材料所共有;检测出的杂合标记位点中,23个为增效标记位点,13个为减效标记位点,其中杂合标记位点RM231、RM209可使F1的单株粒重增加13.50 %和16.43 %。该结果可为华南地区杂交稻育种的亲本改良及选配提供了理论指导。 相似文献
975.
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
976.
Calcium borohydride is a potential candidate for onboard hydrogen storage because it has a high gravimetric capacity (11.5 wt.%) and a high volumetric hydrogen content (~130 kg m?3). Unfortunately, calcium borohydride suffers from the drawback of having very strongly bound hydrogen. In this study, Ca(BH4)2 was predicted to form a destabilized system when it was mixed with LiBH4, NaBH4, or KBH4. The release of hydrogen from Ca(BH4)2 was predicted to proceed via two competing reaction pathways (leading to CaB6 and CaH2 or CaB12H12 and CaH2) that were found to have almost equal free energies. Using a set of recently developed theoretical methods derived from first principles, we predicted five new hydrogen storage reactions that are among the most attractive of those presently known. These combine high gravimetric densities (>6.0 wt.% H2) with have low enthalpies [approximately 35 kJ/(mol?1 H2)] and are thermodynamically reversible at low pressure within the target window for onboard storage that is actively being considered for hydrogen storage applications. Thus, the first-principles theoretical design of new materials for energy storage in future research appears to be possible. Figure
Calculated van’t Hoff plot for reactions (10-24*) listed in the Ca-M(Li, Na, K)-B-H system (Tables 2–4). The region within the rectangular box corresponds to desirable temperatures and pressures for on-board hydrogen storage PH2 = 1-700 bar and T = 233 to +355 K 相似文献
977.
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
978.
Qi Liang Lu Wen Jun Song Jun Wei Meng Jian Guo Wan 《Journal of molecular modeling》2013,19(3):1205-1209
The possibility of a new endohedral fullerene with a trapped aluminum carbide cluster, Al4C @C80-I h , was theoretical investigated. The geometries and electronic properties of it were investigated using density functional theory methods. The Al4C unit formally transfers six electrons to the C80 cage which induces stabilization of Al4C@C80. A favorable binding energy, relatively large HOMO-LUMO gap, electron affinities and ionization potentials suggested the Al4C@C80 is rather stable. The analysis of vertical ionization potential and vertical electron affinity indicate Al4C@C80 is a good electron acceptor. Figure
An endohedral fullerene with a trapped aluminum carbide cluster, Al4C @C80-I h , was investigated using density functional theory. A favorable binding energy, relatively large HOMO-LUMO gap, electron affinities and ionization potentials suggested it is rather stable 相似文献
979.
Fang-ping Wang Guo-ping Zhan Yu-ren Jiang Jing-nan Guo Zhi-gang Yin Rui Feng 《Journal of molecular modeling》2013,19(8):3135-3142
The adsorption behaviors of three carboxyl hydroxamic acids on diaspore (010) and kaolinite (001) have been studied by density functional theory (DFT) and molecular dynamics (MD) method. The results indicated that carboxyl hydroxamic acids could adsorb on diaspore surface by ionic bonds and hydrogen bonds, and adsorb on kaolinite surface by hydrogen bonds. The models of carboxyl hydroxamic acids adsorbed on diaspore and kaolinite surfaces are proposed. Figure
Carboxyl hydroxamic acids with different number of polar groups on the surfaces of diaspore (010) and kaolinite (001) 相似文献
980.
Zhi‐Jian Li Guy S. S. Njateng Wen‐Jia He Hong‐Xia Zhang Jian‐Long Gu Shan‐Na Chen Zhi‐Zhi Du 《化学与生物多样性》2013,10(11):2032-2041
The essential oil obtained by hydrodistillation from the aerial parts of Aristolochia delavayi Franch. (Aristolochiaceae), a unique edible aromatic plant consumed by the Nakhi (Naxi) people in Yunnan, China, was investigated using GC/MS analysis. In total, 95 components, representing more than 95% of the oil composition, were identified, and the main constituents found were (E)‐dec‐2‐enal (52.0%), (E)‐dodec‐2‐enal (6.8%), dodecanal (3.35%), heptanal (2.88%), and decanal (2.63%). The essential oil showed strong inhibitory activity (96% reduction) of the production of bacterial volatile sulfide compounds (VSC) by Klebsiella pneumoniae, an effect that was comparable with that of the reference compound citral (91% reduction). Moreover, the antimicrobial activity of the essential oil and the isolated major compound against eight bacterial and six fungal strains were evaluated. The essential oil showed significant antibacterial activity against Providencia stuartii and Escherichia coli, with minimal inhibitory concentrations (MIC) ranging from 3.9 to 62.5 μg/ml. The oil also showed strong inhibitory activity against the fungal strains Trichophyton ajelloi, Trichophyton terrestre, Candida glabrata, Candida guilliermondii, and Cryptococcus neoformans, with MIC values ranging from 3.9 to 31.25 μg/ml, while (E)‐dec‐2‐enal presented a lower antifungal activity than the essential oil. 相似文献