动物杂交试验的正反交循环设计法

为了提高配合力等参数估测的有效性、准确性和经济性。本文从动物自身的和试验的具体特点出发,提出了一种适于(1)客观条件仅允许试验部分组合、(2)试验目的仅为确定杂交育种的种群选配方案、(3)完全双列杂交试验分地分批进行等三种情况的新杂交试验设计法——正反交循环法,并且探讨了由这种设计法所设计的试验,即正反交循环杂交试验的最小二乘分析。     

创造小麦品种一般配合力测验种的新型工具—太谷核不育小麦

了解小麦品种各性状的配合力,是进行品 种改良的基础工作之一。品种的一般配合力是 该品种与若干其它品种杂交第一代的平均表 现,是衡量基因加性效应的重要指标［[1.31O 测定 小麦品种的一般配合力通常采用双列杂交等方 法,不过由于杂交工作量大,一次不能测定很多 材料。我国发现的太谷核不育小麦是由显性雄 性不育基因控制的不育小麦［[a3。利用这个小麦 异花授粉的特点,可以创造一个配合力测验种, 使小麦也能够象玉米等异花授粉作物那样应用 测验杂交测定品种的一般配合力[31。在待测品 种与侧验种杂交的时候,待测品种的性细胞在 受精过程中与测验种不同基因型的性细胞有各 种可能的结合方式。因此,待测品种与杂合测 验种杂交,在意义上与待测品种同许多在基因 型上不同的其它纯合品种杂交有同等价值,待 测品种与杂合测验种的一个杂交组合相当于待 侧品种与其它品种杂交的许多组合。所以,通 过测验杂交,可以比较准确地测知品种的一般 配合力。本文通过对一套双列杂交和一个测验 杂交测得的一般配合力效应值的比较,说明太 谷核不育小麦可以用作创造小麦品种配合力测 验种的工具。     

基于总体最小二乘方法的基因表达缺失数据估计

在基因芯片实验中,数据缺失客观存在,并在一定程度上影响芯片数据后续分析结果的准确性。在不增加实验次数的情况下,缺失值估计是降低缺失数据对后续分析影响的有效方法。针对基因表达数据含有噪声的特点,提出了基于总体最小二乘估计的基因表达缺失值估计算法。实验结果表明,新的估计算法具有比传统缺失值估计算法更好的稳定性和估计准确度。     

从农艺性状和分子标记鉴定一个水稻三倍体x二倍体F2群体的遗传稳 …

一自然发生的三倍体水稻材料与二倍体杂交,在Ｆ２代获得了一个稳定群体。群体形态表现,农艺性状分析和微卫星标记三个方面的研究表明：该杂交Ｆ２群体确系两个亲本的杂交的杂交后代。在杂交后有重组发生并迅速纯合,因而在形态上和遗传上呈现稳定性。对水稻中出现的这种早代稳定现象的利用和途径发生机制进行了探讨．     

兰属植物种间杂交亲和性研究

以10个中国兰品种和8个大花蕙兰品种为材料开展了兰属植物间的杂交试验,比较不同组合的杂交亲和性。结果表明:(1)54个杂交组合,共授粉582朵,获得杂交果实131个,平均结实率为22.51%;中国兰与大花蕙兰正交结实率(23.19%)高于反交结实率(9.27%)。(2)墨兰与大花蕙兰无论正交或反交均可获得较高的结实率,其亲和性高于春兰、建兰与大花蕙兰杂交的亲和性。(3)中国兰种间杂交亲和性较高,3类组合结实率均大于30%,但不同品种间杂交亲和性不一,春兰‘绿萼’,墨兰‘企黑’、‘白墨’,建兰‘金荷’,大花蕙兰‘黄金岁月’比较适宜做母本;春兰‘大富贵’,墨兰‘富贵’、‘白墨’,大花蕙兰‘月影’、‘日本绿’和‘黑珍珠’比较适宜做父本。     

杂交试验中的最佳样本含量

杂交试验是一项费时费钱的工作,因此在进行试验之前如能进行严密的设计,给出试验所需的样本大小是十分必要的,统计学中常见的估计样本容理的公式不宜应用于杂交试验,本文分两种情况给出了杂交试验中样本容量的估计公式,据此估计出的样本容量安排杂交试验,可在满足试验者要求的条件下,使试验的总成本最低或使试畜的总头数最少。     

4个春性基因型小麦品种与‘京841’杂交F_1代的表型分析

选用4个具有不同显性春化基因型的小麦品种与冬性小麦品种‘京841’进行杂交实验,通过显性春化基因特异性PCR分析技术鉴定杂交F1代植株,并分析4个杂交组合的正反交F1代植株表型特性。结果显示,各显性春化基因已经导入到各杂交F1代植株中,且其苗穗期受显性春化基因的控制而有效缩短;3个杂交组合的F1代穗粒数在正反交之间存在显著差异,推测穗粒数受细胞质遗传因素的影响较大,其中以‘新春2号’和‘豫麦18’分别为母本和父本与‘京841’杂交后F1代的穗粒数表现出较强的杂种优势,4个杂交组合的F1代千粒重均表现出较强的杂种优势。     

放牧型羔羊生产的杂交组合优化

为了探讨放牧型羔羊肉生产的优化杂交组合,寻求高原生境下细毛羊种质资源的高效利用,以引进的特克塞尔、澳洲美利奴、白萨福克和邦德品种羊为父本,以甘肃高山细毛羊为母本开展杂交试验研究;并采用人工输精方法于11月集中配种,翌年4月产羔;同时观测各组杂种羔羊初生、断奶、6月龄和12月龄的体质量,并于断奶、6月龄和12月龄分别开展屠宰试验,分析其肉用性能。结果表明:特克塞尔与甘肃高山细毛羊杂交F1代(特甘细)的平均初生、断奶和6月龄的体质量分别为5.53、27.86和31.24kg,显著高于其他杂交组合(P0.05);6月龄到12月龄各杂交组合羔羊生长速度慢;断奶时特甘细胴体质量达14.25kg,极显著的高于其他组合(P0.01);6月龄时特甘细胴体质量为14.55kg,也极显著的高于其他组合(P0.01);断奶和6月龄时特甘细的屠宰率(除断奶时澳甘细外)和胴体净肉率均比其他组合高,而骨肉比低于其他组合。从不同阶段杂种羔羊生长速度和屠宰结果分析,特甘细组合是放牧条件下生产羔羊肉的最优杂交组合。     

从农艺性状和分子标记鉴定一个水稻三倍体×二倍体F_2群体的遗传稳定性

一自然发生的三倍体水稻(OryzasativaL.)材料(SAR_3)与二倍体(生47)杂交,在F2代获得了一个稳定群体。群体形态表现、农艺性状分析和微卫星标记三个方面的研究表明:该杂交F2群体确系两个亲本的杂交后代,在杂交后有重组发生并迅速纯合,因而在形态上和遗传上呈现稳定性。对水稻中出现的这种早代稳定现象的利用途径和发生机制进行了探讨     

利用人工杂交方法研究转基因对植物遗传多样性的影响

如何分析转基因对植物遗传多样性的影响一直以来是一个难题。提出了一种所谓“人工杂交”的分析方法 ,即利用具有相同遗传背景的转基因及其野生型植物群体 ,分别与一组具有代表性的遗传对象进行有性杂交 ,通过考察它们后代主要性状分离变异状况来评估转基因导入对群体遗传性状的多样性的影响。作为一个实例 ,选用了由转基因水稻及其野生型组成的 3对不同遗传群体 ,分别与 7个具有代表性 (如不同亚种、不同品种类型等 )的水稻品种进行杂交 ,获得 15对杂交组合 ,经杂种 F1 自交获得 F2 种子 ,通过观测 F2 分离世代的主要性状分离状况 ,比较和统计转基因水稻群体及其野生型群体后代的性状分离程度。结果表明 ,提出的“人工杂交”技术路线是可行的 ,为全面和深入开展相关研究开辟了一个新途径。同时根据本研究利用这 3对转基因水稻及其野生型群体的研究结果表明 ,在一些性状上转入的外源基因可以显著地增加种群内的遗传变异而在另外一些性状上却显著地减少了种群内的遗传变异 ,但尚不能得出或支持转基因植物可能对遗传多样性产生负面效应的结论。     

A new method for describing predator-prey relations in discontinous environments

I propose a new method for anlysing predatorprey interactive systems in discontinuous environments. The basic index used here is a generalized version ofLloyd 's (1967) “interspecies mean crowding”, which is defined as the number of individuals of one species existing in a given patch per that of the other species in either the same or different patches at either the same or different times. Four indices are derived from different combinations of the numbers of the prey and the predator in habitat patches. Then, the correlation coefficients between the numbers of individuals in patches in both different locations and times are derived by modifying the above new indices. Using this technique, dynamical changes of the joint distributions of the numbers of predators and prey which reflect variation in local conditions, can readily be described. As an example, this method was applied to an analysis of the outcomes of a multi-patch version of theLotka-Volterra model of predator-prey interactions.     

梅花鹿DRB 第二外显子等位基因鉴定的一种新方法

A new method was found which integrated Motif specific-PCR, SSCP and direct sequencing to identify the exon 2 of alleles of DRB genes in sika deer. Using this method, the detected 15 sequences which included no artificial sequences from mutation or recombination in the process all met the criterion to distinguish a new allele. The criterion is that there have to be identical sequences identified from at least two different individuals by PCR and direct sequencing. Compared with PCR-SSCP-cloning sequencing previously, this method can efficiently remove artificial sequences. Combined with the above criterion, this method provided a new approach for investigating DRB gene polymorphism of sika deer and other deer species.     

基于属性分离存储的种质数据组织方法

传统的作物种质数据组织方法,针对不同作物种类建立不同数据表,这种方法已不能有效适应种质数据综合分析的需要.本文提出了一种基于属性分离存储的种质数据组织方法,根据种质的每个属性分别建立数据表,各属性间没有从属关系.该方法可统一数据查询操作,优化查询过程,提高分析效率,具有灵活、可扩展的特点,可以方便地集成与种质分析相关的数据,适用于种质资源分布式数据库和相关信息系统的建立.     

The use of smoke acid as an alternative coagulating agent for natural rubber sheets' production

A comparative study of rubber sheets obtained using formic, acetic, and smoke acid as coagulants is shown for latex obtained from native Amazonian trees and also from commercial cultivated trees. The evaluation of both processes of coagulation was carried out by spectroscopic and physical-chemical analysis, showing no differences in the rubber sheets obtained. This new method of rubber sheet preparation was introduced into Amazonian rainforest rubber tapper communities, which are actually producing in large scale. The physical-mechanical properties were similar among a large sheets made by different rubber tapper communities using this new method.     

Development of a Standardized and Safe Airborne Antibacterial Assay,and Its Evaluation on Antibacterial Biomimetic Model Surfaces

Bacterial infection of biomaterials is a major concern in medicine, and different kinds of antimicrobial biomaterial have been developed to deal with this problem. To test the antimicrobial performance of these biomaterials, the airborne bacterial assay is used, which involves the formation of biohazardous bacterial aerosols. We here describe a new experimental set-up which allows safe handling of such pathogenic aerosols, and standardizes critical parameters of this otherwise intractable and strongly user-dependent assay. With this new method, reproducible, thorough antimicrobial data (number of colony forming units and live-dead-stain) was obtained. Poly(oxonorbornene)-based Synthetic Mimics of Antimicrobial Peptides (SMAMPs) were used as antimicrobial test samples. The assay was able to differentiate even between subtle sample differences, such as different sample thicknesses. With this new set-up, the airborne bacterial assay was thus established as a useful, reliable, and realistic experimental method to simulate the contamination of biomaterials with bacteria, for example in an intraoperative setting.     

蛋白含量检测的抗干扰新方法

为提高蛋白质含量检测方法的抗干扰能力,从福林酚试剂法入手,以牛血清白蛋白为标准样品,重新设计制定实验试剂组成与配比等,获得蛋白质含量检测新方法,然后探讨新方法的适用检测波长范围和稳定性,并利用细胞全蛋白裂解液分析它对多种常见干扰物质的包容性。实验发现,新方法不仅能准确检测蛋白质含量,对蛋白质测定液中表面活性剂的耐受浓度,如十二烷基硫酸钠(SDS)、NP-40和TritonX-100分别达到10%、2%和1%;螯合剂乙二胺四乙酸二钠盐(EDTA)和Ethylene glycol bis(2-aminoethyl)tetraacetic acid(EGTA)则分别达25 mmol/L和1 mmol/L;对还原剂二硫苏糖醇(DTT)和β-ME的包容浓度均为1 mmol/L;而含氮化合物硫酸铵与尿素则分别为0.5 mol/L和4 mol/L。与原方法相比较,对常见干扰物质的耐受性有显著提高,说明新方法适用含多种干扰物质的蛋白质溶液,在生命科学研究领域具有广泛应用前景。     

Heterogeneity‐constrained random resampling of phytosociological databases

Aim: Phytosociological databases often contain unbalanced samples of real vegetation, which should be carefully resampled before any analyses. We propose a new resampling method based on species composition, called heterogeneity‐constrained random (HCR) resampling. Method: Many subsets of the source vegetation database are selected randomly. These subsets are sorted by decreasing mean dissimilarity between pairs of the vegetation plots, and then sorted again by increasing variance of these dissimilarities. Ranks from both sortings are summed for each subset, and the subset with the lowest summed rank is considered as the most representative. The performance of this method was tested using simulated point patterns that represented different levels of aggregation of vegetation plots within a database. The distributions of points in the subsets resulting from different resampling methods, both with and without database stratification, were compared using Ripley's K function. The mean of random selections from an unbiased sample was used as a reference in these comparisons. The efficiency of the method was also demonstrated with real phytosociological data. Results: Both stratified and HCR resampling yielded selection patterns more similar to the reference than resampling without these tools. Outcomes from the resampling that combined these two methods were the most similar to the reference. The efficiency of the HCR resampling method varied with different levels of aggregation in the database. Conclusions: This new method is efficient for resampling phytosociological databases. As it only uses information on species occurrences/abundances, it does not require the definition of strata, thereby avoiding the effect of subjective decisions on the selection outcome. Nevertheless, this method can also be applied to stratified databases.     

一种用于显微观察的蓟马标本的制片新方法

蓟马（昆虫纲：缨翅目）是昆虫纲中有重要经济意义的目之一,由于个体微小,因此需要制作成高质量的玻片在高倍显微镜下观察和研究。如果玻片标本质量欠佳,常常导致无法鉴定其种类。不同的研究中处理蓟马标本的技术和方法各异。本文介绍一种新的制片方法,这一方法需要更少的化学药品,且适合处理深颜色的标本。而且,用这个方法处理的标本清晰,保持其自然体色,这些特征在鉴定种类时是十分必要的。本方法处理标本包括4个步骤：氢氧化钾透明（一般5％一10％KOH溶液中,常温放置1～2d或者100℃水浴加热1～2h,处置时间随材料大小和颜色的深浅有所变化）、纯酒精脱水（材料透明后转移到纯酒精中浸泡4—5min）、Hoyer＇s介质装片（滴一滴Hoyer＇s介质于载玻片中央,而后将脱水后的材料转移至介质中,用细拨针小心整翅、足以及触角的姿态,盖上盖玻片）和干燥贴标签（装片后放置在35～45℃烘箱中2～3d或者室温下放置1星期,然后将采集信息、寄主信息以及鉴定表格制成标签,贴于玻片两侧）,与其它制片方法相比,此法最简洁。文末对不同的制片方法作了比较和讨论。     

Construction of linear invariants in phylogenetic inference.

An analytical method is presented for constructing linear invariants. All linear invariants of a k-species tree can be derived from those of (k-1)-species trees using this method. The new method is simpler than that of Cavender, which relies on numerical computations. Moreover, the new method provides a convenient tool to study the relationships between linear invariants of the same tree or of different trees. All linear invariants of trees of up to five species are derived in this study. For four species, there are 16 independent linear invariants for each of the three possible unrooted trees, 14 of which are shared by two unrooted trees and 12 of these are shared by all three unrooted trees; the last types of linear invariants can be used to construct tests on the assumptions about nucleotide substitutions. The number of linear invariants for a tree is found to increase rapidly with the number of species.     

The stepwise two-photon excited melanin fluorescence is a unique diagnostic tool for the detection of malignant transformation in melanocytes

Malignant transformation of melanocytes is associated with changes in melanogenesis. Therefore, fluorescence of melanin may be an informative indicator of this process. But the conventionally excited autofluorescence of melanin in skin tissue is ultra-weak and its main part in the visible spectral region is hidden by the much stronger fluorescence from other endogenous fluorophores. Here, using a new mode of stepwise two-photon excitation, melanin-dominated fluorescence spectra of pigmented skin lesions are reported. From these, pure melanin fluorescence spectra of normal pigmented skin, melanocytic nevi and malignant pigmented melanoma were analyzed. They show distinctly different spectral shapes: melanoma gave a characteristic fingerprint with a fluorescence band peaking at 640 nm, independent of the melanoma subtype. The melanin fluorescence spectra peaked at 590 nm for all types of common melanocytic nevi. These differences in the fluorescence spectra are probably based on different contents of eumelanin and pheomelanin. In a series of 167 cases with melanocytic nevi and melanomas, the sensitivity of this new method to diagnose melanoma was 93.5%, the specificity 80.0% and the diagnostic accuracy 82.6%. The two-photon excitation fluorescence method is a new diagnostic tool which may in future supplement conventional dermatohistopathology.