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Wheat pre-harvest sprouting (PHS) can cause significant reduction in yield and end-use quality of wheat grains in many wheat-growing areas worldwide. To identify a quantitative trait locus (QTL) for PHS resistance in wheat, seed dormancy and sprouting of matured spikes were investigated in a population of 162 recombinant inbred lines (RILs) derived from a cross between the white PHS-resistant Chinese landrace Totoumai A and the white PHS-susceptible cultivar Siyang 936. Following screening of 1,125 SSR primers, 236 were found to be polymorphic between parents, and were used to screen the mapping population. Both seed dormancy and PHS of matured spikes were evaluated by the percentage of germinated kernels under controlled moist conditions. Twelve SSR markers associated with both PHS and seed dormancy were located on the long arm of chromosome 4A. One QTL for both seed dormancy and PHS resistance was detected on chromosome 4AL. Two SSR markers, Xbarc 170 and Xgwm 397, are 9.14 cM apart, and flanked the QTL that explained 28.3% of the phenotypic variation for seed dormancy and 30.6% for PHS resistance. This QTL most likely contributed to both long seed dormancy period and enhanced PHS resistance. Therefore, this QTL is most likely responsible for both seed dormancy and PHS resistance. The SSR markers linked to the QTL can be used for marker-assisted selection of PHS-resistant white wheat cultivars. Shi-Bin Cai and Cui-Xia Chen contributed equally to this work.  相似文献   
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目的:探讨普理灵疝装置(prolene hernia system,PHS)治疗老年腹股沟疝的临床疗效.方法:回顾性分析新疆维吾尔自治区人民医院2008年12月~2012年12月应用普理灵疝装置治疗的110例老年腹股沟疝患者的临床资料,对手术方法、术后能力恢复、并发症和复发率等项目进行分析.结果:110例老年腹股沟疝患者的手术时间平均50min,其中42例局麻患者术后即能下床活动,68例硬膜外麻醉患者术后第2天能离床活动.本组患者无死亡,无切口感染、缺血性睾丸炎、尿潴留等.术后有排尿困难4例,在12h后症状缓解;部分术后伤口稍微疼痛,于术后1~2天缓解;伤口异物感3例,全部切口Ⅰ期愈合,平均住院时间4d.术后110例随访2~18个月,无明显异物感,无慢性疼痛,无复发病例.结论:PHS可有效降低老年腹股沟疝术后的复发率、手术创伤小,患者恢复快,适合于老年人腹股沟疝的外科治疗.  相似文献   
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The Niemann-Pick type C is a rare neurodegenerative disease that results from loss-of-function point mutations in NPC1 or NPC2, which affect the homeostasis of sphingolipids and sterols in human cells. We have previously shown that yeast lacking Ncr1, the orthologue of human NPC1 protein, display a premature ageing phenotype and higher sensitivity to oxidative stress associated with mitochondrial dysfunctions and accumulation of long chain bases. In this study, a lipidomic analysis revealed specific changes in the levels of ceramide species in ncr1Δ cells, including decreases in dihydroceramides and increases in phytoceramides. Moreover, the activation of Sit4, a ceramide-activated protein phosphatase, increased in ncr1Δ cells. Deletion of SIT4 or CDC55, its regulatory subunit, increased the chronological lifespan and hydrogen peroxide resistance of ncr1Δ cells and suppressed its mitochondrial defects. Notably, Sch9 and Pkh1-mediated phosphorylation of Sch9 decreased significantly in ncr1Δsit4Δ cells. These results suggest that phytoceramide accumulation and Sit4-dependent signaling mediate the mitochondrial dysfunction and shortened lifespan in the yeast model of Niemann-Pick type C1, in part through modulation of the Pkh1-Sch9 pathway.  相似文献   
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Mitogen-activated protein kinase (MAPK) signalling networks are important regulators of environmental responses and developmental processes in plants. To understand the role of MAPK signalling modules in the regulation of plant microtubule functions, we searched for MAPKs that interact with the dual-specificity MAPK phosphatase, PROPYZAMIDE HYPERSENSITIVE 1 ( PHS1 ), whose mutation has previously been reported to confer hypersensitivity to microtubule-disrupting drugs in Arabidopsis. Yeast two-hybrid assays demonstrated that PHS1 specifically interacts with two MAPKs, MPK12 and MPK18. Bimolecular fluorescence complementation (BiFC) studies confirmed that the PHS1 and MPK18 proteins are physically coupled, and that this interaction occurs in the cytoplasm. At the biochemical level, in vitro dephosphorylation assays indicated that phospho-MPK18 can be dephosphorylated by recombinant PHS1. Mutant mpk18 seedlings show defects in microtubule-related functions, and have moderately stabilized microtubules. Absence of MPK18 in the phs1-1 background partially complements the phs1-1 root growth phenotypes, providing genetic evidence for involvement of MPK18 signalling in microtubule-related functions. We propose a model whereby the PHS1–MPK18 signalling module is involved in a phosphorylation/dephosphorylation switch that regulates cortical microtubule functions.  相似文献   
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为了解中国不同麦区小麦种质资源抗穗发芽基因的等位变异与分布特征,利用小麦抗穗发芽相关的Vp1B3和Dorm-1标记对7个不同麦区的446份小麦种质资源的等位变异和分布差异进行了检测。结果表明:(1)利用标记Vp1B3检测出Vp1的等位基因共有3种类型,分别为Vp1Bc(与抗穗发芽相关)、Vp1Ba(与感穗发芽相关)、Vp1Bb(与抗穗发芽相关),其频率分别为62.8%、32.9%和4.3%。(2)标记Dorm-1在供试材料中共检测出2种特异性条带,分别为468bp(DormB1a,与感穗发芽相关)和606bp(DormB1b,与抗穗发芽相关),所占比例分别为98.6%和1.4%。(3)具有DormB1b基因型的种质主要分布在黄淮冬麦区和长江中下游冬麦区,比例分别为5.1%和1.9%;具有(Vp1Bc+Vp1Bb)基因型(组合)的种质在长江中下游冬麦区和西南冬麦区分布最多,比例分别为75.0%和74.1%。(4)通过标记Vp1B3和Dorm-1的综合鉴定,共筛选出同时携带Vp1与Dorm-B1位点种质6份,分别是‘陕麦611’、‘郑农19’、‘豫49-198’、‘信阳0913’、‘咸阳大穗’与‘徐州8066’,可以作为抗穗发芽育种的参考亲本。  相似文献   
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Under some circumstances, electric vehicles (EVs) can reduce overall environmental impacts by displacing internal combustion engine vehicles (ICEVs) and by enabling more intermittent renewable energy sources (RES) by charging with surplus power in periods of low demand. However, the net effects on greenhouse gas (GHG) emissions of adding EVs into a national or regional electricity system are complex and, for a system with significant RES, are affected by the presence of storage capacity, such as pumped hydro storage (PHS). This article takes the Portuguese electricity system as a specific example, characterized by relatively high capacities of wind generation and PHS. The interactions between EVs and PHS are explored, using life cycle assessment to compare changes in GHG emissions for different scenarios with a fleet replacement model to describe the introduction of EVs. Where there is sufficient storage capacity to ensure that RES capacity is exploited without curtailment, as in Portugal, any additional demand, such as introduction of EVs, must be met by the next marginal technology. Whether this represents an average increase or decrease in GHG emissions depends on the carbon intensity of the marginal generating technology and on the fuel efficiency of the ICEVs displaced by the EVs, so that detailed analysis is needed for any specific energy system, allowing for future technological improvements. A simple way to represent these trade‐offs is proposed as a basis for supporting strategic policies on introduction of EVs.  相似文献   
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C Yanisch-Perron  J Vieira  J Messing 《Gene》1985,33(1):103-119
Three kinds of improvements have been introduced into the M13-based cloning systems. (1) New Escherichia coli host strains have been constructed for the E. coli bacteriophage M13 and the high-copy-number pUC-plasmid cloning vectors. Mutations introduced into these strains improve cloning of unmodified DNA and of repetitive sequences. A new suppressorless strain facilitates the cloning of selected recombinants. (2) The complete nucleotide sequences of the M13mp and pUC vectors have been compiled from a number of sources, including the sequencing of selected segments. The M13mp18 sequence is revised to include the G-to-T substitution in its gene II at position 6 125 bp (in M13) or 6967 bp in M13mp18. (3) M13 clones suitable for sequencing have been obtained by a new method of generating unidirectional progressive deletions from the polycloning site using exonucleases HI and VII.  相似文献   
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The general thermodynamic principles behind pH driven conformational transitions of biological macromolecules are well understood. What is less obvious is how they can be used to engineer pH switches in proteins. The acid unfolding of staphylococcal nuclease (SNase) was used to illustrate different factors that can affect pH-driven conformational transitions. Acid unfolding is a structural transition driven by preferential H+ binding to the acid unfolded state (U) over the native (N) state of a protein. It is the result of carboxylic groups that titrate with more normal pKa values in the U state than in the N state. Acid unfolding profiles of proteins reflect a balance between electrostatic and non-electrostatic contributions to stability. Several strategies were used in attempts to turn SNase into an acid insensitive protein: (1) enhancing global stability of the protein with mutagenesis or with osmolytes, (2) use of high salt concentrations to screen Coulomb interactions, (3) stabilizing the N state through specific anion effects, (4) removing Asp or Glu residues that titrate with depressed pKa values in the N state, and (5) removing basic residues that might have strong repulsive interactions in the N state at low pH. The only effective way to engineer acid resistance in SNase is not through modulation of pKa values of Asp/Glu but by enhancing the global stability of the protein. Modulation of pH-driven conformational transitions by selective manipulation of the electrostatic component of the switch is an extremely difficult undertaking.  相似文献   
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