新的 MEN1基因剪切突变导致多发性内分泌腺瘤病I型的家系研究

目的对1例多发性内分泌腺瘤病I型（MEN1）患者进行基因诊断和家系成员的随访。方法收集MEN1患者的临床及家系资料，抽取先证者及5位家系成员外周血提取DNA，对MEN1基因的10个外显子进行PCR扩增，用全自动测序仪进行测序分析。结果（1）经MEN1基因突变检测证实,先证者存在内含子5剪切位点的突变（IVS7+2 T→G）。（2）先证者无临床表现的儿子也携带此突变，在基因诊断7个月后出现了明显的临床表现，术后病理证实为胰岛β细胞瘤和左肾上腺腺瘤。结论临床医师应常规对所有MEN1患者及其家系高危成员尽早进行基因突变分析和筛查，并严格随访，从而改善疾病的预后。     

非小细胞肺癌EGFR基因第一内含子（CA）n多态性与基因突变及预后的关系

目的研究非小细胞肺癌（NSCLC）患者表皮生长因子受体（EGFR）基因第一内含子（CA）n[intron 1（CA）n]多态性与EGFR基因突变的关系,并观察患者的预后。方法观察129例NSCLC患者生存情况,检测患者手术切除新鲜癌组织或石蜡包埋组织EGFR基因intron 1（CA）n及19、21外显子突变。结果129例NSCLC患者中,检出EGFR基因突变35例（27.1%）,其中EGFR19外显子21例（16.3%）,21外显子15例（11.6%）。EGFR intron 1（CA）n出现频率最多的等位基因为（CA）20（38.8%）,其次为（CA）16（26.4%）。短（CA）n与EGFR基因突变有关,特别是19外显子突变,差异有统计学意义（均P＜0.05）,但与21外显子突变无明显相关,差异无统计学意义（P＞0.05）。（CA）16与19外显子突变有关,差异有统计学意义（P＜0.05）。EGFR基因intron 1短（CA）n与长（CA）n NSCLC患者总生存时间差异无统计学意义（P＞0.05）。结论 EGFR第一内含子短（CA）n,特别是（CA）16重复序列可能是影响19外显子缺失突变的一个重要因素。（CA）n多态性不是NSCLC患者预后的危险因素（P＞0.05）。     

基于结构矩阵的DNA序列的相似性模型

通过一维映射把DNA序列转化为时间序列,即把数字1,2,3,4分别分配给组成DNA序列的核苷酸A,T,G,C,用时间序列的结构矩阵来描述DNA序列的结构特征,并根据结构矩阵的一些性质定义了结构矩阵的相似性度量,进而利用结构矩阵之间的相似性度量构建了比较DNA序列的相似性模型,以9个不同物种的β-球蛋白基因的第一个外显子(表1)为例验证了该模型的适用性.并得到了较好得结果.     

初诊急性髓系白血病患者FLT3-ITD和NPM1基因联合突变与临床特征的关系

目的探讨初发急性髓系白血病（AML）患者中FMS样酪氨酸激酶3-基因内部串联重复（FLT3-ITD）和核仁磷酸蛋白1（NPM1）基因突变的发生频率,并进一步分析其与患者临床特征的关系。方法收集44例临床初诊为AML的成人患者骨髓标本,通过基因组DNA-PCR技术对FLT3-ITD和NPM1基因突变进行检测。结果44例患者共检测到FLT3-ITD突变10例,检出率22.7%。FLT3-ITD突变阳性的10例患者和无突变者初诊WBC中位数分别为（98.5±22.5）×109/L和（42.9±12.4）×109/L,两者相比具有统计学差异（P＜0.05）。44例患者共检测到NPM1突变14例,检出率31.8%。大部分突变患者,染色体核型正常。结论FLT3-ITD和NPM1基因突变是AML患者中常见的分子生物学异常,对患者的临床和预后有影响。     

浙江地区汉族人群 IL-27p28基因多态性与克罗恩病的相关性研究

目的探讨IL-27p28基因启动子区g.-964 T＞C、第2外显子区g.2905T＞G和第4外显子区g.4730T＞C 3个位点的多态性与浙江地区人群克罗恩病（CD）的相关性。方法选取75例浙江地区汉族CD患者（病例组）及80例健康体检者（对照组）,采用聚合酶链反应-连接酶检测,分析两组基因型频率及等位基因频率。结果对照组的基因型分布符合Hardy- Weinberg平衡定律。两组g.-964位点的基因型频率及等位基因频率的差异有统计学意义（P＜0.05）,而g.2905和g.4730位点的基因频率及等位基因频率的差异无统计学意义（P＞0.05）。结论 IL-27p28基因多态位点g.-964 T＞C可能与浙江地区汉族人群CD易感性有关, g.2905T＞G和g.4730T＞C多态性与浙江地区汉族人群CD无关。     

Bernoulli概型在遗传学上的一个应用

<正> 一、问题的提出现在有个雌雄各半的随机交配大群体,其中某一对基因已经完全纯合,所有个体基因都是MM,现在在某一个体中发生了一个突变,即M→m,如果这个个体与另一个MM的个体交配了两个子女(或更多个子女),这两个子女可能都是MM;也可能一个是MM,另一个是Mm;也可能两个都是Mm。现在要问这三种情况出现的概率各是多少?     

双特征参数基因识别算法实现

基因识别问题首要的工作是对数字化后的基因序列利用离散傅里叶变换(DFT)进行频谱分析.对于很长的DNA序列,功率谱或信噪比计算量很大,推导出了DNA序列在Voss映射、Z-curve映射和实数映射下的信噪比快速算法,以及在Voss映射与Z-curve映射下的信噪比的关系.针对阈值确定的问题提出了基于滑动窗口的局部阈值的算法,在分类时达到了很好的效果.另外,实现了基于移动序列信噪比曲线的基因识别方法.最后,由于DNA序列的3-周期性实际上反映了核苷酸在基因序列的三个子序列上分布的"非均衡性",因此引入"方差均值"特征来衡量该非均衡性,提出了基于方差均值的单因素基因识别方法及以信噪比和方差均值作为特征向量,并设计多项式分类器的基因识别算法.     

对教材中一道例题的变式推广

新课标教材高中数学B版·数学4第103页有一道例2:已知A、B是直线l上任意两点,O是l外一点,求证:对直线l上任一点P,存在实数t,使→OP关于基底{→OA,→OB}的分解式为→OP=(1-t)→OA+t→OB(*),并且满足(*)的点一定在l上.……     

一道椭圆与直线高考压轴老题新探

题目:已知椭圆的中心为坐标原点O,焦点在x轴上,斜率为1且过椭圆右焦点F的直线交椭圆于A、B两点,→OA+→OB与a=(3,-1)共线.(Ⅰ)求椭圆的离心率;(Ⅱ)设M为椭圆上任意一点,且→OM=λ→OA+μ→OB(λμ∈R),证明λ2+μ2为定值.(2005年高考数学试题全国卷文科第22题,理科第21题)笔者最近将该老题的第二问新做,产生了一些新的思路,供读者品鉴.     

一种最短路问题的遗传算法求解

针对最短路径问题,在分析传统遗传算法不足的基础上提出了变长染色体遗传算法(ClvGA),详细论叙了其编码、基因插入(删除、变异)算子的设计,最后通过两个网络对ClvGA进行了实验仿真,结果表明:该方法在最短路径问题上表现出较好的鲁棒性.     

A REPRESENTATION FORMULA RELATED TO SCHR(O)DINGER OPERATORS

Schr(o)dinger operator is a central subject in the mathematical study of quantum mechanics.Consider the Schrodinger operator H = -△ V on R, where △ = d2/dx2 and the potential function V is real valued. In Fourier analysis, it is well-known that a square integrable function admits an expansion with exponentials as eigenfunctions of -△. A natural conjecture is that an L2 function admits a similar expansion in terms of "eigenfunctions" of H, a perturbation of the Laplacian (see [7], Ch. Ⅺ and the notes), under certain condition on V.     

CONTENTS OF VOLUME 30

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Instructions for contributions

正Applied Mathematics-A Journal of Chinese Universities,Series B(Appl.Math.J.Chinese Univ.,Ser.B)is a comprehensive applied mathematics journal jointly sponsored by Zhejiang University,China Society for Industrial and Applied Mathematics,and Springer-Verlag.It is a quarterly journal with     

Journal of Mathematical Research with Applications Guide for Authors

正Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Applied Mathematics,is a home for original research papers of the highest quality in all areas of mathematics with applications.The target audience comprises:pure and applied mathematicians,graduate students in broad fields of sciences and technology,scientists and engineers interested in mathematics.     

Staircase transportation problems with superadditive rewards and cumulative capacities

A cumulative-capacitated transportation problem is studied. The supply nodes and demand nodes are each chains. Shipments from a supply node to a demand node are possible only if the pair lies in a sublattice, or equivalently, in a staircase disjoint union of rectangles, of the product of the two chains. There are (lattice) superadditive upper bounds on the cumulative flows in all leading subrectangles of each rectangle. It is shown that there is a greatest cumulative flow formed by the natural generalization of the South-West Corner Rule that respects cumulative-flow capacities; it has maximum reward when the rewards are (lattice) superadditive; it is integer if the supplies, demands and capacities are integer; and it can be calculated myopically in linear time. The result is specialized to earlier work of Hoeffding (1940), Fréchet (1951), Lorentz (1953), Hoffman (1963) and Barnes and Hoffman (1985). Applications are given to extreme constrained bivariate distributions, optimal distribution with limited one-way product substitution and, generalizing results of Derman and Klein (1958), optimal sales with age-dependent rewards and capacities.To our friend, Philip Wolfe, with admiration and affection, on the occasion of his 65th birthday.Research was supported respectively by the IBM T.J. Watson and IBM Almaden Research Centers and is a minor revision of the IBM Research Report [6].     

Laminations minimales résiduellement à 2 bouts

Résumé On décrit toutes les feuilles des laminations minimales dont un ensemble résiduel de feuilles ont 2 bouts.      

Best approximation by downward sets with applications

We develop a theory of downward sets for a class of normed ordered spaces. We study best approximation in a normed ordered space X by elements of downward sets, and give necessary and sufficient conditions for any element of best approximation by a closed downward subset of X. We also characterize strictly downward subsets of X, and prove that a downward subset of X is strictly downward if and only if each its boundary point is Chebyshev. The results obtained are used for examination of some Chebyshev pairs （W,x）, where ∈ X and W is a closed downward subset of X     

Boundedness of multilinear operators on weighted herz type spaces

In this paper, the author establishes the boundedness of multilinear operators on weighted Herz spaces and Herz-type Hardy spaces. The author also obtains their weak estimates on endpoints. As a special case, the conclusions may lead to the weighted estimates for multilinear Calderon-Zygmund operators.     

THE EXACT CONVERGENCE RATE AT ZERO OF LAGRANGE INTERPOLATION POLYNOMIAL TO |x|α

In this paper we present a generalized quantitative version of a result due to M. Revers concerning the exact convergence rate at zero of Lagrange interpolation polynomial to f(x) = |x|α with on equally spaced nodes in [-1, 1].