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991.
Ling Xie Cui Liu Li Wang Harsha P. Gunawardena Yanbao Yu Ruyun Du Debra J. Taxman Penggao Dai Zhen Yan Jing Yu Stephen P. Holly Leslie V. Parise Yisong Y. Wan Jenny P. Ting Xian Chen 《Cell reports》2013,3(3):678-688
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992.
Baowei ZHANG Xin HUANG Tao PAN Liang ZHANG Wenliang ZHOU Tao SONG Demin HAN 《亚洲两栖爬行动物研究(英文版)》2013,(4):282-287
Aimed to evaluate the phylogenetic position of the recently described Protobothrops dabieshanensis Huang et al. (2012), phylogenic relationships of 12 species within Protobothrops based on four mtDNA gene fragments (12S RNA, 16S RNA, ND4 and Cyt b) were reconstructed in our study. The result indicates a clade composed ofP dabiesha- nensis, P. jerdonii and P xiangchengsis with strong support. The genetic distance among P dabieshanensis, P jerdonii and P xiangchengsis was much lower than other congeners. Based on the data from the phylogenetic analysis and pre- viously described morphological differences, we conclude that P dabieshanensis is a valid species with close affinities to P jerdonii and P xiangchengsis. 相似文献
993.
A new species of the genus Leptolalax is described from Doi Saket, Chiang Mai Province, northern Thailand. The new species is distinguished from its congeners by the following combination of characters: 1) adult size large(male SVL 45.8-52.5 mm); 2) tympanum distinct; 3) skin of dorsal surface mostly smooth, with distinct tubercles on dorsal and lateral parts of the body; 4) ventrolateral glandular ridge distinct and complete; 5) lateral body and groin covered with dark brown or black spots; 6) throat, chest, and belly nearly immaculate white; and 7) bi-colored iris, upper onethird golden, and lower two-thirds gray. Molecular phylogenetic analysis of mitochondrial 16S rRNA further distinguishes it from its congeners for which sequences are available. 相似文献
994.
Arthur Nathan Brodsky Jing Zhang Richard P. Visconti Sarah W. Harcum 《Biotechnology progress》2013,29(5):1298-1306
Stem cells are needed for an increasing number of scientific applications, including both fundamental research and clinical disease treatment. To meet this rising demand, improved expansion methods to generate high quantities of high quality stem cells must be developed. Unfortunately, the bicarbonate buffering system – which relies upon an elevated CO2 environment – typically used to maintain pH in stem cell cultures introduces several unnecessary limitations in bioreactor systems. In addition to artificially high dissolved CO2 levels negatively affecting cell growth, but more importantly, the need to sparge CO2 into the system complicates the ability to control culture parameters. This control is especially important for stem cells, whose behavior and phenotype is highly sensitive to changes in culture conditions such as dissolved oxygen and pH. As a first step, this study developed a buffer to support expansion of mesenchymal stem cells (MSC) under an atmospheric CO2 environment in static cultures. MSC expanded under atmospheric CO2 with this buffer achieved equivalent growth rates without adaptation compared to those grown in standard conditions and also maintained a stem cell phenotype, self‐renewal properties, and the ability to differentiate into multiple lineages after expansion. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:1298–1306, 2013 相似文献
995.
Xin?Yin Yuezhi?Lin Weigang?Cai Ping?WeiEmail author Xiaojun?WangEmail author 《Virology journal》2013,10(1):356
Background
Equine infectious anemia virus (EIAV) is an important animal model for understanding the relationship between viral persistence and the host immune response during lentiviral infections. Comparison and analysis of the codon usage model between EIAV and its hosts is important for the comprehension of viral evolution. In our study, the codon usage pattern of EIAV was analyzed from the available 29 full-length EIAV genomes through multivariate statistical methods.Finding
Effective number of codons (ENC) suggests that the codon usage among EIAV strains is slightly biased. The ENC-plot analysis demonstrates that mutation pressure plays a substantial role in the codon usage pattern of EIAV, whereas other factors such as geographic distribution and host translation selection also take part in the process of EIAV evolution. Comparative analysis of codon adaptation index (CAI) values among EIAV and its hosts suggests that EIAV utilize the translational resources of horse more efficiently than that of donkey.Conclusion
The codon usage bias in EIAV is slight and mutation pressure is the main factor that affects codon usage variation in EIAV. These results suggest that EIAV genomic biases are the result of the co-evolution of genome composition and the ability to evade the host’s immune response.996.
采用形态学观察和分子鉴定方法对2011年在陕西省发生的一种烟草未知病害的病原菌进行鉴定。从病叶组织分离纯化得到病原菌,通过致病性测定以及人工接种后再分离病菌,证明编号LJL007的菌株为该病的致病菌。依据病原菌的形态学和培养特征,将菌株LJL007鉴定为灰葡萄孢Botrytis cinerea Pers.,其有性型为富氏葡萄孢盘菌Botryotinia fuckeliana Whetzel。通过核糖体DNAITS序列分析,分离菌株LJL007序列(登录号:HM17900)与富氏葡萄孢盘菌序列(登录号:HM849615)同源性达100%,进一步证明该病原菌是灰葡萄孢Botrytis cinerea。云芝多糖在离体条件下,对灰葡萄孢的菌丝生长和孢子萌发均无直接抑制作用。云芝多糖对烟草灰霉病有较好预防保护作用,其预防效果可达56.29%。云芝多糖可显著提高烟草体内几丁质酶和β-1,3-葡聚糖酶活性,其活性峰值分别比对照提高56.89%和429.83%,说明云芝多糖可诱导植物产生抗病性。 相似文献
997.
Chunyan Chen Tian Shen Fei Tian Ping Lin Qingtian Li Zelin Cui Yajuan Zhang Min Xue Jing Ye Xiaokui Guo YuhuaZhou 《Acta biochimica et biophysica Sinica》2013,(12):1039-1048
Community-acquired pneumonia (CAP) is a major concern in hospitals and the bacterial community of which has not been systemically discussed yet. Sputum from patients in the acute stages is a kind of accessible sample reflecting its fea- tures. In our study, we analyzed 45 sputum samples from 45 patients with CAP. Eighteen sputum samples from healthy people were chosen as the controls. Pyrosequencing of the 16s rDNA V3 hypervariable regions of aH the bacteria con- tained in the sputum was used as a culture-independent method to disclose the community constitution. Also, our published data for hospital-acquired pneumonia (HAP) in sputum was used for comparison. By pyrosequencing, 〉90,000 DNA reads were detected. After being analyzed by tools in the Ribosomal Database Project, the reads were clas- sified into five main phyla and 〉100 genera. At the phyla level, the reads' distribution of CAP is similar to that of healthy people and at genera level, the occurrence of each genus possesses their feature in three categories. Genera such as Streptococcus and Neisseria showed stability in their percentages, indicating that such genera are rarely affected by exogenous bacteria or antibiotics. The role of other genera such as Moraxella and Rothia in CAP should be emphasized. According to our analysis, the bacterial communities of CAP are with slight change when compared with those of healthy people, but have a large gap between HAP. Meanwhile, Rothia might be an important endogenous pneumonia-causing factor. 相似文献
998.
Aixia Li Wenlong Yang Xueyuan Lou Dongcheng Liu Jiazhu Sun Xiaoli Guo Jing Wang Yiwen Li Kehui Zhan Hong-Qing Ling Aimin Zhang 《植物学报(英文版)》2013,55(11):1026-1037
Plant height is an important agronomic trait. Dramatic increase in wheat yield during the "green revolution" is mainly due to the widespread utilization of the Reduced height (Rht)-1gene. We analyzed the natural allelic variations of three homoeologous loci Rht-A1, Rht-B1, and Rht-D1 in Chinese wheat (Triticum aestivum L.) micro-core collections and the Rht-B1/D1 genotypes in over 1,500 bred cultivars and germplasms using a modified EcoTILLING. We identified six new Rht-A1 allelic variations (Rht-Alb-g), eight new Rht-B1 allelic variations (Rht-Blh-o), and six new Rht-D1 allelic variations (Rht-Dle-j). These allelic variations contain single nucleotide polymorphisms (SNPs) or small insertions and deletions in the coding or uncoding regions, involving two frame-shift mutations and 15 missenses. Of which, Rht-Dle and Rht-Dlh resulted in the loss of interactions of GID1-DELLA-GID2, Rht-Blicould increase plant height. We found that the Rht-Blh contains the same SNPs and 197 bp fragment insertion as reported in Rht-Blc. Further detection of Rht-Blh in Tibet wheat germplasms and wheat relatives indicated that Rht-Blc may originate from Rht-Blh. These results suggest rich genetic diversity at the Rht-1 loci and provide new resources for wheat breeding. 相似文献
999.
目的:建立糖尿病合并牙周炎大鼠模型,观察比较近牙槽嵴区牙周膜内肿瘤坏死因子-a(TNF-a)的含量,探讨高血糖对牙周组织炎症程度的影响。方法:糖尿病大鼠(STZ组)模型采用链脲佐菌素一次性腹腔注射制备,单纯牙周炎组州组)注射同剂量的枸橼酸钠缓冲液。成模且稳定后(4周),两组都采用大鼠牙颈部丝线结扎的方法诱导牙周炎模型,于结扎后1周,2周,3周处死大鼠,采用组织学方法,免疫组织化学结合MATLAB7.0.1图像灰度定量分析法,研究近牙槽嵴区牙周膜中TNF-a水平的变化及牙周组织炎症的进展程度。结果:N组与STZ组除0周外各时间点两组之间比较有显著性差异(P〈0.001);N组内各时间点每两组之间比较有统计学差别(P〈0.05);STZ组内各时间点每两组之间比较有统计学差别(P〈0.05)。随时间的增加,各组大鼠的炎症程度增加,TNF—a的表达水平增加,STZ组的病变进展程度显著重于N组。结论:一次性腹腔注射STZ+牙颈部丝线结扎可成功建立实验性糖尿病大鼠的牙周炎模型。高血糖浓度使糖尿病大鼠牙槽骨TNF-a的表达水平增加,降低了机体的损伤一修复能力,牙周组织的炎症进一步加重。 相似文献
1000.
目的:探究舒芬太尼与曲马多对用于小儿鼾症手术苏醒期躁动的作用与影响。方法:60例ASAI或II级扁桃体肥大或腺样体肥大的鼾症手术患儿,年龄6-14岁,无呼吸系统,循环系统等疾病,一般状态良好。随机分为舒芬太尼组(s组)和曲马多(T组),每组各30例。常规监测各项生命体征。于手术结束前20分钟(min),S组缓慢静脉输入0.15μg/kg舒芬太尼,T组静脉输入1.2mg/kg曲马多。观察各组的:平均动脉压 (MAP)、心率(HR)、血氧饱和度(SpO2),进行各组的镇静评分(RSS)、躁动评分(RS)、镇痛评分(VRS)、意识状态评分(OAAS)。记录拔管前(T0)、拔管时(T1)、拔管后5min(T2)、拔管后10min(T3)、拔管后20min(T4)各时间点各参数的变化。记录各组的恶心呕吐、呼吸抑制、烦躁等的发生率。结果:SpO2各组间无显著差异。MAP,HR在各时间点的变化T组大于S组,P〈0.05,有显著差异。T组在RS,RSS,VRS评分与S组有显著差异,P〈0.05。结论:0.15μg/kg的舒芬太尼在小儿鼾症手术的苏醒期可以维持稳定的血流动力学,副作用小,镇痛效果良好,可以有效减少小儿苏醒期的躁动。 相似文献