普通小麦Brock中一个抗白粉病新基因AFLP标记P13/M13250的筛选

用225对AFLP引物组合，对白粉病敏感小麦品种京411，抗病品种Brock和以京411为轮回亲本、Brock为抗源供体育成的近等基因系（NILs）进行分子标记筛选，其中，引物组合P13／M13能在抗、感材料间稳定产生P13／M13-250bp的多态性片段．用Brock与京411杂交R代抗、感分离单株，对P13／M13 250进行了初步连锁性鉴定，该标记对小麦植物抗病育种分子标记辅助选择有一定用处．     

犏牛及其亲本IGF2基因mRNA表达水平、DNA甲基化状态差异分析

黄牛与牦牛远缘杂交一代犏牛表现出很强的杂种优势,但其雄性不育使得杂种优势的利用受到了极大限制．为了从表观遗传学角度研究这一生殖隔离现象的生理机制,通过Real—timePCR检测了犏牛及其亲本睾丸组织中IGF2基因mRNA表达水平,并用亚硫酸氢钠测序法检测了血液和睾丸组织中IGF2基因第10外显子DMR区DNA甲基化状态．结果发现犏牛睾丸组织中IGF2基因mRNA表达水平最低,与亲本的表达水平差异极显著（P〈0．01）;牛（犏牛、黄牛和牦牛）血液和睾丸中IGF2基因的DNA甲基化程度均较高（90％以上）,其中犏牛高于其亲本,但没有达到显著水平．实验结果说明IGF2基因mRNA表达水平与牛精子发生有关,可能在牛的精子发生过程中发挥重要作用,并可能与犏牛雄性不育有关;IGF2基因第10外显子DMR区的甲基化与IGF2基因在犏牛及其双亲睾丸中的表达差异无关,可能是其他的机制参与调节IGF2基因的表达．     

茅坪种子植物区系研究

茅坪亚热带地区有种子植物120科446属831种;大科及较大科中主产温带的科占较大比例;大属中主要以温带类型为主;茅坪地区与太白山、化龙山作比较,其热带成分比例高于太白山（18．4％）低于化龙山（29．9％）,而温带成分比例低于太白山（67．5％）高于化龙山（57．9％）,这与它所处的地理位置相符合,也反映出该地处于亚热带北缘和暖温带南缘的过渡地带。茅坪植物种类丰富多样,区系成分复杂;种子植物区系具有明显的古老性,单种属所占比例大;区系以温带成分为主,同时表现出明显的过渡特点;地理成分复杂是多种区系成分的汇聚地。     

一类半线性椭圆方程（组）整体大解的存在性

A．V．Lair,A．W．Wood（2000）和A．V．IJair（2010）的文章‘}1分别介绍了半线性椭圆方程／tu：P（｜x｜）u^α以及方程组Au=p（｜x｜）u^α,△v=q（｜X｜）v^β径向整体大解的存在性,其中P,q是R^n上的非负连续函数,0〈α,β≤1．笔者研究了参数满足条件d,p〈0时半线性椭圆方程／tu=p（｜x｜）u^α及相应方程组径向整体大解存在的充要条件,补充了α／〈0（或α,β〈0）时A．V．Lair,A．W．Wood（2000）和A．V．Lair（2010）的相应结果．     

OaO—Al2O3-OaF2-SiO2渣系的黏度

采用内旋转圆柱法测量了不同组成的CaO-Al2O3-CaF2-SiO2渣系的黏度,采用XRD分析技术对高温熔炼渣的物相进行分析,并计算了各渣样的黏流活化能．结果表明：当叫（CaO）／w（Al2O3）一定,配渣中SiO2质量分数低于8％时,对渣样的高温黏度并没有明显的影响,在1490℃以上时,熔渣黏度都低于0．5Pa·s当SiO2质量分数增加到10％,渣样的高温黏度开始显著降低,温度高于1440℃时,黏度值低于0．2Pa·s．随着SiO2含量的增加,熔渣的碱度逐渐降低,破坏了原来熔渣的大网状结构,熔渣的黏度明显降低．渣系的黏流活化能变化趋势与渣样的黏度值变化趋势一致．     

内标——循环伏安法对葡萄酒中乙醇测定的研究

本文论述内标──循环伏安法（INSTD-CV）测定葡萄酒中乙醇（RtOH）的有关问题．在内标物质亚铁氰化钾（K4Fe（CN）6）浓度为2mM,支持电解质［NaOH］浓度为0．1M时,INSTD－CV法结果的精密度范围为1．4～1．9％RSD（n=8）,准确度以回收率表示范围为98．2～102．5％（V．／V．）．当置信度为99％时,方法的检出限为0．025％（V．／V．）（S／N=3）,校准曲线的线性范围为0．075～8．00％（V．／V．）EtOH．效果比无内标的CV法更佳．本文对内标──循环伏安图形特征,电化学分析中内标选择问题、公共切线法的氧化峰电流测量问题,校准曲线的回归统计问题等,亦加以讨论．     

对白粉病敏感、抗性栽培小麦及杂交后代的蛋白质组分析

感病小麦京411、抗病小麦Brock及杂交后代近等基因系感染白粉菌后,发现京411感病,Brock和近等基因系抗病,因此白粉病抗性呈显性．对上述3种小麦的叶片进行蛋白质组分析,在感小麦的京411中有一个8kD／pI 5．3的特异蛋白,该蛋白在抗病品种Brock和杂交后代近等基因系中不存在,后者的蛋白质谱型与Brock相同．上述结果表明,幼苗抗白粉病特性的遗传与蛋白质谱型的遗传相类似,此结果也许可以为生产上筛选抗白粉病小麦品种提供生化依据．     

干扰素对慢性乙型肝炎患者肝功能及肝纤维化的疗效

目的观察应用干扰素α1β治疗慢性乙型肝炎（乙肝）患者改善其肝纤维化情况的疗效。方法2007年1月～2009年8月期间我院门诊经病理确诊的慢性乙肝致肝纤维化患者67例,随机分为干扰素治疗组（35例）和对照组（32例）,两组均给予常规中药（扶正化淤胶囊）保肝降酶治疗,干扰素治疗组加用干扰素a1β（赛若金）40腭肌肉注射,隔日1次,疗程均为24周。观察两组患者症状、体征,肝功能指标如丙氨酸转氨酶（ALT）、胆红素（BIL）、白蛋白（ALB）和白蛋白／球蛋白比例（A／G）以及血清胆碱酯酶（ChE）、转化生长因子（TGF—β1）和透明质酸（HA）的含量。结果与对照组相比,干扰素治疗组肝功能显著好转。治疗组AⅡ为（58．8±26．4）U／L,高于对照组（129．6±36．9）U／L（P〈0．01）;治疗组BⅡ为（31．0±17．9）μmoL／L,低于对照组（49．3±19．6）μmol／L（P〈0．01）;治疗组ALB（40．5±6．6）g／L,高于对照组（32．1±6．1）g／L（P〈0．01）;白蛋白／球蛋白比例（A／G）对照组高于治疗组（P〈0．01）。肝纤维化指标也有显著改善,如血清ChE治疗组（3919±101）U／L、对照组（2289±191）U／L（P〈0．01）;TGF－β1治疗组（101±31）μg／L、对照组（144±19）μg／L（P〈0．01）;HA治疗组（91．6±36．2）μg／L、对照组（149．1±30．9）μg/L（P〈0．01）。治疗组患者腹胀及肝区疼痛有不同程度的缓解,脾肿大有较大程度的缓解。结论应用干扰素a1β治疗慢性乙肝导致的肝纤维化患者,可改善患者的临床症状、体征,促进肝功能在生化指标方面的恢复并缓解肝纤维化。     

芦笋汁的抗突变作用

用微核（MN）试验、姐妹染色单体交换（SCE）及精子畸形试验探讨芦笋汁对环磷酰胺（CTX）致突变作用的影响,结果表明,单纯芦笋汁对小鼠骨髓细胞MN和SCE及精子畸形均无明显影响,但一定剂量芦笋汁可使CTX诱发的MN率（6．00％）降低（5．03％－2．66％）,SCE（29．22次／细胞）减少（26．40－13．37次／细胞）,精子畸形率（6．10％）下降（5．12％－2．86％）,均呈现剂量－效应关系。     

水分胁迫对B优827生理特性和产量性状的影响

对籼型杂交水稻B优827和中度抗旱品种冈优725（对照）分蘖期进行了正常水分条件（相对含水量100％,V/V）、轻度水分胁迫（相对含水量70％,V／V）、重度水分胁迫（相对含水量50％,V／V）的水分胁迫处理9d,研究了光合速率、超氧离子（O2-）、抗氧化酶（SOD、CAT）活性等生理特性和产量性状的变化。B优827在分蘖期轻度水分胁迫、重度水分胁迫下都表现为抗干旱能力比冈优725强;轻度胁迫和重度水分胁迫下,随着胁迫时间的增加,光合速率都会下降、活性氧物质含量上升、抗氧化酶含量也相应上升。而且重度水分胁迫下,光合速率下降迅速,活性氧及其抗氧化酶含量比轻度胁迫下耍高．但胁迫第9d酶活性出现下降．说明机体詈到了严莺的榀伤．     

Patterns of DNA cytosine methylation between haploids and corresponding diploids in rice

In higher plant, about 30% cytosines are methy-lated[1], among which about 90% methylated sites lie in CpG dinucleotide and CpNpG trinucleotide[2]. The me-thylated DNA has inducing and epigenetic effects on cell biological procedures such as gene differen…     

白粉菌对抗、感白粉病小麦品种叶片组织侵染情况的研究

采用透明染色法对白粉菌15号生理小种侵染的小麦叶片进行处理,观察不同时间段白粉菌对京411,Brock及其杂交后代近等基因系（NIL）叶片的侵染情况。结果表明：Brock,NIL抗病耐受性均强于京411,此结果可为今后抗病基因的克隆、植物抗性信号转导机制等研究提供细胞学上的依据。     

Analysis of DNA methylation variation in wheat genetic background after alien chromatin introduction based on methylation-sensitive amplification polymorphism

During the process of alien germplasm introduced into wheat genome by chromosome engineering, extensive genetic variations of genome structure and gene expression in recipient could be induced. In this study, we performed GISH （genome in situ hybridization） and AFLP （amplified fragment length polymorphism） on wheat-rye chromosome translocation lines and their parents to detect the identity in genomic structure of different translocation lines. The results showed that the genome primary structure variations were not obviously detected in different translocation lines except the same 1RS chromosome translocation. Methylation sensitive amplification polymorphism （MSAP） analyses on genomic DNA showed that the ratios of fully-methylated sites were significantly increased in translocation lines （CN12, 20.15%; CN17, 20.91%; CN18, 22.42%）, but the ratios of hemimethylated sites were significantly lowered （CN12, 21.41%; CN17, 23.43%; CN18, 22.42%）, whereas 16.37% were fully-methylated and 25.44% were hemimethylated in case of their wheat parent. Twenty-nine classes of methylation patterns were identified in a comparative assay of cytosine methylation patterns between wheat-rye translocation lines and their wheat parent, including 13 hypermethylation patterns （33.74%）, 9 demethylation patterns （22.76%） and 7 uncertain patterns （4.07%）. In further sequence analysis, the alterations of methylation pattern affected both repetitive DNA sequences, such as retrotransposons and tandem repetitive sequences, and low-copy DNA.     

Aberrant DNA methylation in cloned ovine embryos

By using the approach of immunofluorescence staining with an antibody against 5-methylcytosine （5MeC）, the present study detected the DNA methylation patterns of cloned ovine embryos. The embryos derived from in vitro fertilization were also examined for reference purpose. The results showed that： （1） during the preimplantation development, cloned embryos displayed a similar demethylation profile to the fertilized embryos; that is, the methylation level decreased to the lowest at 8-cell stage, and then increased again at morulae stage. However, methylation level was obviously higher in cloned embryos than in stage-matched fertilized embryos, especially at 8-cell stage and afterwards; （2） at blastocyst stage, the methylation pattern in cloned embryos was different from that in fertilized embryos. In cloned blastocyst, inner cell mass （ICM） exhibited a comparable level to trophectoderm cells （TE）, while in in-vitro fertilized blastocyst the methylation level of ICM was lower than that of TE, which is not consistent with that reported by other authors. These results indicate that DNA methylation is abnormally reprogrammed in cloned embryos, implying that aberrant DNA methylation reprogramming may be one of the factors causing cloned embryos developmental failure.     

Demethylation of CpG islands in embryonic cells

DNA in differentiated somatic cells has a fixed pattern of methylation, which is faithfully copied after replication. By contrast, the methylation patterns of many tissue-specific and some housekeeping genes are altered during normal development. This modification of DNA methylation in the embryo has also been observed in transgenic mice and in transfection experiments. Here we report the fate in mice of an in vitro-methylated adenine phosphoribosyltransferase transgene. The entire 5' CpG island region became demethylated, whereas the 3' end of the gene remained modified and was even methylated de novo at additional sites. Transfection experiments in vitro show that the demethylation is rapid, is specific for embryonic cell-types and affects a variety of different CpG island sequences. This suggests that gene sequences can be recognized in the early embryo and imprinted with the correct methylation pattern through a combination of demethylation and de novo methylation.     

DNMT1 and DNMT3b cooperate to silence genes in human cancer cells

Inactivation of tumour suppressor genes is central to the development of all common forms of human cancer. This inactivation often results from epigenetic silencing associated with hypermethylation rather than intragenic mutations. In human cells, the mechanisms underlying locus-specific or global methylation patterns remain unclear. The prototypic DNA methyltransferase, Dnmt1, accounts for most methylation in mouse cells, but human cancer cells lacking DNMT1 retain significant genomic methylation and associated gene silencing. We disrupted the human DNMT3b gene in a colorectal cancer cell line. This deletion reduced global DNA methylation by less than 3%. Surprisingly, however, genetic disruption of both DNMT1 and DNMT3b nearly eliminated methyltransferase activity, and reduced genomic DNA methylation by greater than 95%. These marked changes resulted in demethylation of repeated sequences, loss of insulin-like growth factor II (IGF2) imprinting, abrogation of silencing of the tumour suppressor gene p16INK4a, and growth suppression. Here we demonstrate that two enzymes cooperatively maintain DNA methylation and gene silencing in human cancer cells, and provide compelling evidence that such methylation is essential for optimal neoplastic proliferation.     

Detection of DNA methylation changes during seed germination in rapeseed （Brassica napus）

DNA methylation is a common yet important modi- fication of DNA in eukaryotic organisms. DNA methy- lation, especially methylation of cytosine (m5C), have both epigenetic and mutagenic effects on various cellu- lar activities such as differential gene exp…     

高活力水稻种子萌发过程中DNA甲基化变化的MSAP分析

DNA甲基化是基因组DNA的一种主要表观遗传修饰形式,是调节基因组功能的重要手段。本实验采用MSAP方法分析,旨在研究高活力水稻种子萌发过程中的甲基化与去甲基化变化的规律,为研究种子的老化机理和种子的长期保存提供依据。结果表明:水稻种子萌发过程中,同时发生了甲基化与去甲基化作用,且去甲基化作用先于甲基化作用发生。发生去甲基化可能与基因活化有关,发生甲基化可能与组织特异性有关。     

Expression of lysine-rich protein gene and analysis of lysine content in transgenic wheat

Expression vector pBPC102, which carries winged bean lysine-rich protein (wblrp) gene and dihydropicolinate synthase (DHDPS) gene, was transferred into hexaploid winter wheat cv. Jinghua No.l, Jing411, You899 and Yangnongl5 explants of immature inflorescence and immature embryos by particle bombardment. More than 100 transgenic plants were obtained under the selection of s-(2-aminoethyl)-L-cysteine (AEC). Confirmed transgenic plants of To and TI generation by PCR and PCR-Southern blotting analyses showed successful integration of wblrp gene into wheat genome. Analysis of transgenic plant lines of T2 by Northern dot-blotting showed good expression of wblrp gene in offspring seed. The content of free lysine in leaves, contents of bound lysine and total proteins in seeds of T2 transgenie wheat lines were determined and analyzed. Among 34 tested transgenic lines, levels of free lysine content in leaves of 9 transgenic lines are 2~3times higher than un-trans-formed wild-type cultivars. Among 17 analyzed transgenic lines, bound lysine content of 4 transgenic lines is more than 10% higher than that of wild-type cultivars. Our research suggests that introducing wblrp gene into wheat is an effective way to improve its nutrition quality.