放线菌来源活性天然产物发现研究进展

放线菌(Actinomycetes)是抗生素等活性天然产物的重要来源，在临床治疗病原菌感染等重大疾病方面发挥着重要作用。由于抗生素滥用等原因导致临床上出现的以耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus, MRSA)等为代表的耐药病菌的种类和数量急剧增加，对人类生存造成了重大威胁。结合现代生物技术进展，加大放线菌来源新抗生素的开发力度刻不容缓。本文对新时期放线菌来源抗生素的发现现状、基于生理操作和基因操作的放线菌来源天然产物挖掘的技术方法等进行综述，以期对放线菌来源活性天然产物的发现提供借鉴。     

GC32细胞对三种虫媒病毒的敏感性研究

用胃癌细胞株ＧＣ３２,对乙型脑炎、基孔肯雅、兰加特病毒进行敏感性研究。并用ＢＨＫ２１细胞作对照,发现ＧＣ３２细胞对两种病毒的敏感性与对照细胞ＢＨＫ２１极为接近。ＢＨＫ２１和ＧＣ３２细胞对基孔肯雅、乙型脑炎和兰加特的免疫荧光实验,于感染后４８ｈ或７２ｈ都出现＋＋＋～＋＋＋＋的阳性结果。两种细胞对基孔肯雅和乙型脑炎病毒都形成空斑,ＢＨＫ２１细胞对基孔肯雅和乙型脑炎病毒的空斑形成单位分别为５．６５和５．３６;ＧＣ３２对基孔肯雅和乙型脑炎病毒的空斑形成单位分别为６．４８和５．６１。实验表明,ＧＣ３２细胞可以作为有关病毒实验的理想细胞株。     

DNA分子标记在动物个体识别与亲权鉴定方面的应用

自从DNA分子标记技术建立以来,各种DNA分子标记相继被广泛地应用于遗传图谱的构建,评估遗传多样性以及个体识别,亲权鉴定等方面,综述了利用DNA分子标记技术,进行动物个体识别与亲权鉴定的原理,研究进展,现状及其应用前景与存在的问题。     

The conservation of the belted beauty Lycia zonaria britannica (Lepidoptera, Geometridae) in the United Kingdom

Recent surveys have established that the belted beauty moth Lycia zonaria britannica, which is an endemic subspecies found only in the British Isles, now occurs at just three sites in England and Wales. Populations at all three sites are small, with annual peak counts of usually less than 50 females. At Morfa Conwy in Wales and Meols Common in England, habitat quality has been declining for more than a decade as open, herb-rich, early successional dune grassland is replaced by fixed, rank grassland. Uniquely at Sunderland Point in England, the moth is primarily associated with areas of saltmarsh, but distribution is constrained by surrounding farmland and man-made structures. Attempts are now being made to restore areas of open grassland and to return the moth to its former distribution. Since the winter of 2000-2001, small plots of rank grassland on Meols Common have been excavated annually, with all vegetation removed, together with any humic layer present. The exposed bare sand has then been allowed to re-vegetate naturally. Within 18 months, the plots have developed into open, herb-rich habitats suitable for the moth. Adults were recorded on the plots for the first time in spring 2003 and may have been the product of the small numbers of eggs and larvae introduced to the plots in spring 2002. Similar excavations have been initiated at Morfa Conwy, which is in the process of being notified as a Site of Special Scientific Interest (SSSI). A 3-year programme to establish a second Welsh population is underway and, to date, more than 2000 captive-reared larvae have been released on the receptor site which lies 21 km to the east of Morfa Conwy.     

A 5q12.1–5q12.3 microdeletion in a case with a balanced exceptional complex chromosomal rearrangement

Complex chromosomal rearrangements are very rare chromosomal abnormalities. Individuals with a complex chromosomal rearrangement can be phenotypically normal or display a clinical abnormality. It is believed that these abnormalities are due to either microdeletions or microduplications at the translocation breakpoints or as a result of disruption of the genes located in the breakpoints. In this study we describe a 2-year-old child with mental retardation and developmental delay in whom a de novo apparently balanced exceptional complex chromosomal rearrangement was found through conventional cytogenetic analysis. Using both cytogenetic and FISH analysis, the patient's karyotype was found to be: 46,XY,der(5)t(5;7)(p15.1;7q34),t(5;8)(q13.1;8q24.1)dn. A large, clinically significant deletion which encompassed 887.69 kb was detected at the 5q12.1–5q12.3 (chr5:62.886.523–63.774.210) genomic region using array-CGH. This deleted region includes the HTR1A and RNF180 genes. This is the first report of an individual with an apparently balanced complex chromosomal rearrangement in conjunction with a microdeletion at 5q12.1–5q12.3 in which there are both mental-motor retardation and dysmorphia.     

生防菌株HG18基因组信息分析与抗菌功能基因挖掘

贝莱斯芽胞杆菌（Bacillus velezensis）HG18是1株低温生防菌株,能够分泌抗菌物质。为挖掘和利用其抗菌功能基因,服务农业生产,采用二、三代相结合测序技术,对其进行全基因组测序,获得菌株完整基因组序列。基因组全长4 461 844 bp,包含一个染色体和一个质粒,GC含量44.06%,编码4 643个基因,编码基因总长度3 893 994 bp,占基因组87.27%。发现6个几丁质降解相关基因,2个葡聚糖酶基因和1个壳聚糖酶基因,2个脂肽类抗菌物质芬芥素与表面活性素合成基因簇,2个细菌素subtilin和bacillolysin合成基因。研究为提高抗菌物质产量的菌株定向遗传改造以及植物抗病育种提供基因资源。     

利用各世代的小区平均数估计遗传参数的加权最小二乘法

本文提出了在随机区组设计下利用六个世代的小区平均数估计加性-显性-二基因互作模型的各参数、检验该模型的加权最小二乘法的基本步骤。     

小麦品种联合试验效应及理论依据──Ⅰ.试验的地点环境效应

本文利用小麦品种区域试验材料,研究了联合试验地点对品种适应性鉴定的致变能力以及对试验区域的代表性,讨论了试验的效果．     

Assessing the skill of yes/no predictions

Summary Should healthy, middle‐aged women receive precautionary mammograms? Should trauma surgeons use the popular TRISS score to predict the likelihood of patient survival? These are examples of questions confronting us when we decide whether to use a yes/no prediction. In order to trust a prediction we must show that it is more valuable than would be our best guess of the future in the absence of the prediction. Calculating value means identifying our loss should the prediction err and examining the past performance of the prediction with respect to that loss. A statistical test to do this is developed. Predictions that pass this test are said to have skill. Only skillful predictions should be used. Graphical and numerical methods to identify skill will be demonstrated. The usefulness of mammograms is explored.