Abnormal pattern detected in fragile-X patients by pulsed-field gel electrophoresis.

The fragile-X syndrome is the most frequent inherited form of mental retardation, with an incidence of 1 in 1,500 males. It is characterized by the presence of a fragile site at Xq27.3 induced in vitro by folate deprivation or by inhibitors of deoxynucleotide synthesis. Its mode of inheritance is unusual for an X-linked trait, with incomplete penetrance in both males and females. Some phenotypically normal males transmit the mutation to all their daughters who rarely express any symptoms, but penetrance is high in sons and daughters of these carrier women. Genetic and physical mapping of the Xq27-q28 region has confirmed that the disease locus is located at or very near the fragile site. Hypotheses proposed to account for the abnormalities in the inheritance of the disease include sequence rearrangements by meiotic recombination or a mutation that affects reactivation of an inactive X chromosome during differentiation of female germ cells. To detect such rearrangements, or methylation changes that may reflect a locally inactive X chromosome, we used pulsed-field gel analysis of DNA from fragile-X patients with probes close to the fragile-X locus. The probe Do33 (DXS465) detected abnormal patterns in fragile-X patients, but not in normal controls or in non-expressing male transmitters.     

非惯性系内的气体浮力问题

本文研究了气体浮力的产生机制，并且重点讨论了非惯性系内的气体浮力问题，给出了有关计算公式。     

基于LDAP协议实现统一的网络管理研究

基于网络上信息存储方式的不统一及其所面临的困难 ,结合复旦大学校园网的特点 ,在深入研究LDAP协议的基础上 ,给出了一套跨协议认证的解决方案 ,提出了关于同步问题的两个模型和基于CSN方法的实现办法     

用测量模态阻尼和振型的方法对复合材料薄平板进行无损质量检测

复合材料薄平板经热压制成后,都需要进行质量检测。本文探索用测量模态阻尼和振型的方法,对复合材料薄平板的制作质量进行无损检测,作为对其它昂贵的无损检测方法的补充。略述用振动方法进行无损检测的原理,测量薄平板阻尼的方法以及提高测量精度的措施。还讨论在测量薄平板阻尼时可能遇到的一些特殊问题(如非线性刚度、拍、模态密集等问题);以云母基复合材料薄平板作为例子,从测量其阻尼和振型的结果,对这种板的制作质量进行讨论。     

Effect of 15(R)-15-methyl-prostaglandin E2 on iron absorption in the rat

Summary The administration of 15(R)-15-methyl prostaglandin E₂ (15(R)-15-M-PGE₂) in vivo significantly diminished the uptake of⁵⁹Fe into blood, spleen, liver, femur and dried intestine of rats, whereas acetylsalicylic acid (ASA) increased the counts significantly. This effect of ASA was counteracted by 15(R)-15-M-PGE₂. It is suggested that prostaglandins (PGs) might play an important role in inhibiting iron absorption at the intestinal level.This work was supported by grant No.6638 from CONICET (Argentina). The technical assistance of Mrs María E. Castro and Norma Rizzo is gratefully acknowleged.     

Host cell reactivation of ozone-treated T3 bacteriophage by different strains ofEscherichia coli

Summary Host cell reactivation capacity for ozone T3 phage was determined for differentE. coli strains deficient in one or more of the DNA repair mechanisms. The results indicate that DNA polymerase I appears to play a key role in the repair of damage produced on the DNA by ozone while thelexA gene product seems to play a minor one.This research was sponsored by the National Sciences and Engineering Council of Canada. One of us (PLH) acknowledges a scholarship from the NSERCof Canada.     

Studies on the Dd antigen-antibody system. I. The nature of antigen Dd and its antibodies

Summary The nature of antigen Dd, an antigen present in the extracts of human dandruff which precipitates human sera selectively, and antibodies reacting with it are reported.This work was supported through U.G.C. Grant No. F.23-230/75/SR II. H.K. participated in this study, first as J.R.F. of U.G.C. and then as S.R.F. of I.C.M.R. We are grateful to Dr Baruch S. Blumberg for his invaluable suggestions and to Professor H. Walter for the gift of IgG, IgM and IgA immune sera.     

伪随机序列的均匀性评价

伪随机序列生成方法有很多种 ,因生成方法不同而导致其性质的差异较大 .文中描述了产生均匀分布的U (0 ,1 )伪随机序列的数学原理 ,提出了评估均匀分布伪随机序列均匀性的几种方法 ,对由软件产生的几种均匀分布序列的均匀性作出了评估     

杨辉三角与行列式

本文用杨辉三角构造了两种类型的行列式，然后逐一讨论了这两类行列式的值，并由此得到了它们一些特例的简洁结果。     

Leaning Towards Agile in 21~(st) Century

Background: During the last fifteen years there ha s been an increased drive for organisations to reduce costs. From a production po int, this has often centred on lean manufacturing and JIT waste elimination proc esses. However, in 1991, the Iaccocca Institute Bethlehem P.A commissioned a re port specifically to analyse the changing nature of the marketplace. As a result , in the following year, the Agile Manufacturing Forum was initiated and the ter m ‘agile or responsive manufacturing‘ was first intr...