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1.
Nineteen novel full-ORF α-gliadin genes and 32 pseudogenes containing at least one stop codon were cloned and sequenced from three Aegilops tauschii accessions (T15, T43 and T26) and two bread wheat cultivars (Gaocheng 8901 and Zhongyou 9507). Analysis of three typical α-gliadin genes (Gli-At4, Gli-G1 and Gli-Z4) revealed some InDels and a considerable number of SNPs among them. Most of the pseudogenes were resulted from C to T change, leading to the generation of TAG or TAA in-frame stop codon. The putative proteins of both Gli-At3 and Gli-Z7 genes contained an extra cysteine residue in the unique domain II. Analysis of toxic epitodes among 19 deduced α-gliadins demonstrated that 14 of these contained 1–5 T cell stimulatory toxic epitopes while the other 5 did not contain any toxic epitopes. The glutamine residues in two specific ployglutamine domains ranged from 7 to 27, indicating a high variation in length. According to the numbers of 4 T cell stimulatory toxic epitopes and glutamine residues in the two ployglutamine domains among the 19 α-gliadin genes, 2 were assigned to chromosome 6A, 5 to chromosome 6B and 12 to chromosome 6D. These results were consistent with those from wheat cv. Chinese Spring nulli-tetrasomic and phylogenetic analysis. Secondary structure prediction showed that all α-gliadins had high content of β-strands and most of the α-helixes and β-strands were present in two unique domains. Phylogenetic analysis demonstrated that α-gliadin genes had a high homology with γ-gliadin, B-hordein, and LMW-GS genes and they diverged at approximate 39 MYA. Finally, the five α-gliadin genes were successfully expressed in E. coli, and their expression amount reached to the maximum after 4 h induced by IPTG, indicating that the α-gliadin genes can express in a high level under the control of T7 promoter.  相似文献   
2.
Ge S  Wang S  Kang X  Duan F  Wang Y  Li W  Guo M  Mu S  Zhang Y 《Cytotechnology》2011,63(6):581-598
According to the ultrastructural characteristic observation of the developing male germ cells, spermatogenesis of the crustacean shrimp, Fenneropenaeus chinensis, is classified into spermatogonia, primary spermatocytes, secondary spermatocyte, four stages of spermatids, and mature sperm. The basic protein transition during its spermatogenesis is studied by transmission electron microscopy of ammoniacal silver reaction and immunoelectron microscopical distribution of acetylated histone H4. The results show that basic protein synthesized in cytoplasm of spermatogonia is transferred into the nucleus with deposition on new duplicated DNA. In the spermatocyte stage, some nuclear basic protein combined with RNP is transferred into the cytoplasm and is involved in forming the cytoplasmic vesicle clumps. In the early spermatid, most of the basic protein synthesized in the new spermatid cytoplasm is transferred into the nucleus, and the chromatin condensed gradually, and the rest is shifted into the pre-acrosomal vacuole. In the middle spermatid, the nuclear basic protein linked with DNA is acetylated and transferred into the proacrosomal vacuole and assembled into the acrosomal blastema. At the late spermatid, almost all of the basic protein in the nucleus has been removed into the acrosome. During the stage from late spermatid to mature sperm, some de novo basic proteins synthesized in the cytoplasm belt transfer into the nucleus without a membrane and almost all deposit in the periphery to form a supercoating. The remnant histone H4 accompanied by chromatin fibers is acetylated in the center of the nucleus, leading to relaxed DNA and activated genes making the nucleus non-condensed.  相似文献   
3.
选取黄土高原区黑岱沟露天煤矿不同复垦阶段(1995~2010年)样地4块,以原地貌样地为对照,以时空替代的方法,对煤矿复垦地的植物群落的功能群结构及生物多样性进行研究.结果表明:(1)随着复垦时间的延长,植物群落功能群组成以多年生禾草和多年生杂类草为主,其累积优势度均呈现增加的趋势,而一、二年生草本的累积优势度减小;复垦初期,群落功能群单一、组成种类贫乏,多为一、二年生植物;复垦后期,羊草及冰草逐步出现,复垦地最终形成以克氏针茅、本氏针茅、赖草及糙隐子草为主的植物群落.(2)复垦过程中,中生植物及中旱生植物所占比例逐步增加,而旱生植物比例逐步减少;多年生禾草及多年生杂类草生物量随着复垦时间的增加而递增,而一、二年生草本植物生物量递减;群落总生物量呈先急剧增加、又急剧减少、后缓慢增加的规律.(3)群落的Shan-non-Wiener多样性指数(H)、Patrick丰富度指数(Pa)及Pielou均匀度指数(JP)随着复垦时间延长而增加.  相似文献   
4.
目的:评估餐时血糖调节剂瑞格列奈(商品名:诺和龙)对老年2型糖尿病(T2DM)患者胰岛β细胞早时相分泌功能的影响及其用药安全性观察。方法:符合入选的患者,完成临床和实验室检查,根据血糖水平及胰岛素释放结果给予单独瑞格列奈口服治疗12周。结果:与基础值比较,瑞格列奈治疗12周后患者餐后2h血糖(2hPG)及糖化血红蛋白(HbAlc)水平均有显著下降,差异有显著性,P〈0.05;空腹血糖(FBG)有所下降但差异无显著性,P〉0.05。治疗前后比较,患者的空腹胰岛素(FINS)水平并无明显升高,P〉0.05;Ins30、Ins60明显升高,P〈0.05;而且Ins120、Ins180有下降趋势但差异无显著性,P〉0.05。△I30/△G30比值明显升高,P〈0.05,AUCINS未见明显变化,P〉0.05。治疗前后比较患者的甘油三酯(TG)水平下降,P〈0.05,总胆固醇(TC),低密度脂蛋白胆固醇(LDL-C)水平有所下降同时高密度脂蛋白胆固醇(HDL—C)水平略有上升,但差异无显著性P〉0.05。治疗前后患者的收缩压(SBP)及舒张压(DBP)均未见明显变化,P〉0.05。治疗过程中只有1例患者在早餐与午餐间出现轻微的低血糖的症状,当时测指尖血糖为3.3mmol/L,进食后症状缓解。应用瑞格列奈治疗后患者的肝肾功能均未见明显的异常,P〉0.05。结论:瑞格列奈治疗可部分恢复老年T2DM早期时相胰岛素分泌,是一种有效的并且耐受性好的口服降糖药。  相似文献   
5.
低浓度NaCl对玉米幼苗光合作用的影响   总被引:2,自引:0,他引:2  
以Hoagland溶液为基础培养液,采用沙培法,研究了0,5,10,20,30mmol/LNaCl对玉米(Zeamays)幼苗光合作用的影响。结果表明,低浓度NaCl(5,10mmol/LNaCl)处理使其叶绿素含量增加,Chla/Chlb增大,PEPCase活性提高,光合速率增强。说明低盐促进玉米的光合作用可能与叶绿素含量增加,Chla/Chlb增大以及PEPCase活性提高有关。  相似文献   
6.
 植物叶绿体与原核生物分裂机制相似,其中MinE蛋白在细菌分裂过程中具有重要作用. 为了研究植物MinE蛋白在叶绿体分裂过程中的功能及其进化,利用RT PCR技术克隆了水稻叶绿体分裂相关基因OsMinE,并在GenBank登录(No. AY496951).OsMinE基因cDNA全长1 035 bp,其ORF为711 bp,编码236个氨基酸.与原核生物MinE蛋白相比,水稻OsMinE具有明显延伸的N端与C端.其N端102个氨基酸残基为预测的叶绿体导肽序列,C端延伸保守,推测赋予植物MinE蛋白新的功能.植物minE基因结构分析显示,水稻、拟南芥、杨树都仅含有1个内含子,且插入位置及相位相同.这表明,该内含子可能在单子叶、双子叶植物分化前产生.水稻OsMinE基因在大肠杆菌细胞中的表达严重影响了细胞的分裂,初步证明了水稻MinE蛋白与原核细胞MinE蛋白功能类似.水稻OsMinE基因的克隆为进一步研究叶绿体的分裂机制奠定了基础.  相似文献   
7.
目的:评估餐时血糖调节剂瑞格列奈(商品名:诺和龙)对老年2型糖尿病(T2DM)患者胰岛β细胞早时相分泌功能的影响及其用药安全性观察。方法:符合入选的患者,完成临床和实验室检查,根据血糖水平及胰岛素释放结果给予单独瑞格列奈口服治疗12周。结果:与基础值比较,瑞格列奈治疗12周后患者餐后2h血糖(2hPG)及糖化血红蛋白(HbA1c)水平均有显著下降,差异有显著性,P<0.05;空腹血糖(FBG)有所下降但差异无显著性,P>0.05。治疗前后比较,患者的空腹胰岛素(FINS)水平并无明显升高,P>0.05;Ins30、Ins60明显升高,P<0.05;而且Insl20、Insl80有下降趋势但差异无显著性,P>0.05。△I30/△G30比值明显升高,P<0.05,AUCINS未见明显变化,P>0.05。治疗前后比较患者的甘油三酯(TG)水平下降,P<0.05,总胆固醇(TC),低密度脂蛋白胆固醇(LDL-C)水平有所下降同时高密度脂蛋白胆固醇(HDL-C)水平略有上升,但差异无显著性P>0.05。治疗前后患者的收缩压(SBP)及舒张压(DBP)均未见明显变化,P>0.05。治疗过程中只有1例患者在早餐与午餐间出现轻微的低血糖的症状,当时测指尖血糖为3.3mmol/L,进食后症状缓解。应用瑞格列奈治疗后患者的肝肾功能均未见明显的异常,P>0.05。结论:瑞格列奈治疗可部分恢复老年T2DM早期时相胰岛素分泌,是一种有效的并且耐受性好的口服降糖药。  相似文献   
8.
灾后消防救援人员创伤后应激障碍分析   总被引:2,自引:0,他引:2       下载免费PDF全文
目的:对地震后消防救援人员创伤后应激障碍(PTSD)的发生率及心理健康状况进行分析。方法:选用创伤后应激评定量表(PCL-C)和中文版事件影响量表(IES-R),对灾后三个月内消防员310人进行评估。结果:灾后三个月内PTSD症状的总发生率为35.3%;地震救援组和基层消防组IES-R得分显著高于一般院校组,但地震救援组和基层消防组得分无显著差异,PCL-C得分结果与之类似;恐惧、创伤经历和救援失败等是PTSD症状的影响因素。结论:消防员是职业心理创伤的高危人群,地震后消防救援人员PTSD症状发生率较高,应给予及时心理干预。  相似文献   
9.
Ecological dynamics often show intricate variations in response to different spatial configurations of environmental conditions. For instance, efficient turnover of natural or anthropogenic compounds in soils strongly depends on the bioavailability of these compounds to metabolically active bacteria. Experimental and modelling studies have highlighted that fungal networks may considerably enhance bioavailability by facilitating bacterial dispersal. Therefore, such dispersal networks may play a key role in many soil processes, for example, in contaminant degradation. Particularly, simulation studies revealed that the spatial configurations of networks may be a crucial factor determining the bacterial access to contaminants. Since these spatial configurations are typically complex and not precisely known, suitable metrics describing them in an aggregated manner are required for assessing expected biodegradation benefits from different bacterial dispersal networks. Using a spatially explicit microbial model we randomly created various dispersal network configurations and simulated the resulting bacterial degradation of organic compounds. We investigated numerous spatial metrics for characterizing the manifold network configurations, and identified appropriate metrics based on nonparametric correlation measures. Our results show that single metrics can approximately indicate biodegradation performance, and that well-chosen combinations of two metrics offer very good assessments. Thus, our analysis provides characteristics to focus on when dealing with real fungal networks in future practical applications in environmental management. Moreover, the protocol we employed for deriving the appropriate metrics is suited to be adapted to other ecological studies of functional responses to spatial environmental characteristics, for instance, changes in ecosystem services or biodiversity aspects due to habitat loss and fragmentation.  相似文献   
10.
中国被子植物20个名称后选模式指定   总被引:1,自引:1,他引:0  
查阅保存于中国科学院植物研究所标本馆(PE)的模式标本,发现有20个被子植物名称的模式均多于壹份标本,或同时指定壹号以上的标本为模式,或同时引证壹号以上的标本而没指定模式,根据《国际植物命名法规》(维也纳法规)规则8.1、9.9、9.10和37.2,以及辅则9A.2和9A.3的精神,对这些名称做出后选模式指定。  相似文献   
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