水稻米香基因的初步定位

香味是水稻重要食味品质性状之一,但稻米香味的遗传甚为复杂.早有报道水稻米香基因位于第八条染色体上且与RFLP标记RG28紧密连锁.本实验通过水稻籼粳亚种之间的杂交,利用SSR(Simple Sequence Repeat)分子标记的方法对水稻米香基因进行初步定位.结果表明:稻米香味性状受一对隐性基因控制,且位于第八条染色体SSR标记RM8264和RM1109之间,其遗传距离大约2.1cM.这一结果将对于米香基因的精细定位提供了重要依据.     

基于PCR技术的RGAP分子标记研究进展

基于PCR技术的RGAP分子标记,由于其本身所具有的特点和优越性爱到大家的广泛关注,为近年来分子生物学领域的研究开辟了一个新途径.目前主要应用在克隆和定位抗病基因、分子标记辅助育种、系统植物学研究等方面.本文就RGAP法的基本原理、优越性、目前研究的现状、进展以及研究中还存在的问题分别作以阐述,以期使人们对此标记有个系统的认识.     

《红楼梦》中“也”、“就”、“又”的语用功能分析

《红楼梦》中"也"、"就"、"又"这些起到语用标记的词在文章脉络发展,反映人类对话语控制,体现人类元语用意识等方面起到了一定的作用。人类对自己的话语会进行有意识地监控,以便更好地传达信息、交流沟通,让听话人明白自己的目的、态度,而这种元语用意识就通过这些小品词体现了出来。     

中国英语学习者犹豫型标记语的语用石化现象

本文以 MICASE 的口语讨论部分为参照语料库,对比分析 COLSEC 语料库和自建的研究生口语语料库( GSSC),分析了犹豫型标记语的类别、差异以及学习者潜在的语用石化倾向。本研究揭示出( 1) 中国英语学习者多用无声停顿和重复表述来表示犹豫和话语空缺,而本族语使用者用小词来延缓话语的情形比较常见; ( 2) 在部分小词的使用上,中国英语学习者存在语用石化倾向 在教学中如何引导学生正确认识犹豫型话语并使用何种犹豫型话语来维系话语连贯至关重要。     

有氧运动对糖尿病患者血栓调节蛋白和纤溶系统的影响

以糖尿病患者为研究对象（15名为Ⅰ型糖尿病患者,15名为Ⅱ型糖尿病患者）,通过对他们进行3个月的有氧运动干预,观察糖尿病患者运动前后的血栓调节蛋白、T-PA活性、PAI-1活性等指标的变化,明确运动对糖尿病患者血栓调节蛋白和纤溶系统的影响,从而反映运动对糖尿病患者血管内皮的影响,为指导糖尿病患者运动提供理论依据。实验结果：1.实验前Ⅰ型、Ⅱ型糖尿病患者的TM均高于对照组且差异显著;实验后,Ⅰ型、Ⅱ型糖尿病患者的TM均下降,与实验前相比,有显著性差异。2.Ⅰ型糖尿病患者在实验后比实验前PAI-1有明显增加;Ⅱ型糖尿病患者在实验前后PAI-1无显著性差异。结论：实验后TM的下降可能反映了糖尿病患者内皮功能的改善,可以减少心血管疾病的风险。     

Clones identification of Sequoia sempervirens (D.Don) Endl.in Chile by using PCR-RAPDs technique

A protocol of polymerase chain reaction-random amplified polymorphic DNAs (PCR-RAPDs) was established to analyse the gene diversity and genotype identification for clones of Sequoia sempervirens (D.Don) Endl.in Chile.Ten (out of 34) clones from introduction trial located in Voipir-Viilarrica,Chile,were studied.The PCR-RAPDs technique and a modified hexadecyltrimethylammonium bromide (CTAB) protocol were used for genomic DNA extraction.The PCR tests were carried out employing 10-mer random primers.The amplification products were detected by electrophoresis in agarose gels.Forty nine polymorphic bands were obtained with the selected primers (BG04,BF07,BF 12,BF13,and BF 14) and were ordered according to their molecular size.The genetic similarity between samples was calculated by the Jaccard index and a dendrogram was constructed using a cluster analysis of unweighted pair group method using arithmetic averages (UPGMA).Of the primers tested,5 (out of 60) RAPD primers were selected for their reproducibility and high polymorphism.A total of 49 polymorphic RAPD bands were detected out of 252 bands.The genetic similarity analysis demonstrates an extensive genetic variability between the tested clones and the dendrogram depicts the genetic relationships among the clones,suggesting a geographic relationship.The results indicate that the RAPD markers permitted the identification of the assayed clones,although they are derived from the same geographic origin.     

Clones identification of Sequoia sempervirens (D. Don) Endl. in Chile by using PCR-RAPDs technique

A protocol of polymerase chain reaction-random amplified polymorphic DNAs (PCR-RAPDs) was established to analyse the gene diversity and genotype identification for clones of Sequoia sempervirens (D. Don) Endl. in Chile. Ten (out of 34) clones from introduction trial located in Voipir-Villarrica, Chile, were studied. The PCR-RAPDs technique and a modified hexadecyltrimethylammonium bromide (CTAB) protocol were used for genomic DNA extraction. The PCR tests were carried out employing 10-mer random primers. The amplification products were detected by electrophoresis in agarose gels. Forty nine polymorphic bands were obtained with the selected primers (BG04, BF07, BF12, BF13, and BF14) and were ordered according to their molecular size. The genetic similarity between samples was calculated by the Jaccard index and a dendrogram was constructed using a cluster analysis of unweighted pair group method using arithmetic averages (UPGMA). Of the primers tested, 5 (out of 60) RAPD primers were selected for their reproducibility and high polymorphism. A total of 49 polymorphic RAPD bands were detected out of 252 bands. The genetic similarity analysis demonstrates an extensive genetic variability between the tested clones and the dendrogram depicts the genetic relationships among the clones, suggesting a geographic relationship. The results indicate that the RAPD markers permitted the identification of the assayed clones, although they are derived from the same geographic origin. Project (No. CONICYT-FONDEF PROYECT D01 I 1008) supported by the National Commission of Science and Research of Chile     

学习者过渡语中英语虚拟语气标记使用研究

研究的语料是40篇英语专业二年级学生的作文。结果发现学习者对虚拟语气标记的使用在不同小句中的分布有差异,if条件句从句部分恰当S-标记的使用比例要高于其主句部分的使用比例;后者恰当S-标记的使用比例又高于“光杆”主句,且远高于其他类型从句中恰当S-标记的使用率。中国学生议论文中虚拟语气标记的使用特征说明了学习者对该标记习得的过渡语状态。     

分子标记及其在甘薯种质资源和遗传育种中的应用

植物分子生物学和植物生物技术利用分子标记技术得到了大力发展,分子标记的创新、发展与应用对其起了积极的推动作用,本文就RFLP、AFLP、RAPD、DAF、SSR、CAPS分子标记的原理与技术及其在甘薯种质资源和遗传育种中的应用作一介绍     

具有势函数V(r)=A1r-10-A2r-6+A3r2分子晶体的Hamiltonian本征方程的精确解

本文采用连分法得到描述分子晶体中分子之间的相互作用势V(r)=Atr-10-A2r-6+A3r2(A1,A2,A3＞0)的分子晶体的Hamiltonian算子的精确的能量本征值和能量本征函数.