ML語言的数据类型和抽象类型的同式多型

本文阐明ML核心语言中的类型(缩写)、数据类型及抽象类型三者的同式多型(polymorphism)所赖以作依据的理论和实现问题。     

Relationship between vitamin D receptor BsmI and FokI polymorphisms and anthropometric and biochemical parameters describing metabolic syndrome

Introduction.?It was found that vitamin D may have a direct effect on adipocyte differentiation and metabolism and might be involved in the glucose regulation of insulin secretion, as suggested from the discovery of a nuclear localization of 1,25-(OH)₂D₃ in pancreatic islets. In recent years, several polymorphisms in the VDR gene which are able to alter the activity of VDR protein have been described. The BsmI and FokI polymorphisms were described in relation to obesity and type 2 diabetes.

The aim of the study was to find whether there are associations between BsmI and FokI polymorphisms and anthropometric (BMI, WHR, BP) and biochemical parameters describing metabolic syndrome.

Materials and methods.?Studied were 176 randomly selected men aged 25–65 years (mean: 51.99 years) with a mean BMI of 28.06 kg/m². Two polymorphisms of the VDR gene (FokI and BsmI) were explored using the PCR-RFLP method. Serum glucose, insulin, total cholesterol, LDL, HDL, and TG were measured using commercially available kits.

Results.?It was found that BB carriers tend to have higher BMI (29.00 ± 3.74 versus 26.81 ± 3.76, p = 0.024) and waist circumference (101.79 ± 10.59 versus 96.23 ± 10.35, p = 0.014) compared with the bb genotypes. Similarly, FF and Ff carriers had higher fasting insulin levels than the ff genotypes (12.30 ± 10.26 versus 9.76 ± 5.88, p = 0.001 and 9.76 ± 5.88 vs. 6.35 ± 2.64, p = 0.008), and lover cHDL levels in comparison to ff genotypes (52.28 ± 10.02 versus 60.63 ± 16.58, p = 0.015 and 53.70 ± 12.03 versus 60.63 ± 16.58, p = 0.032. Besides these, no significant differences were found.

Conclusions.?The BsmI VDR polymorphism seems to influence BMI, while the FokI VDR polymorphism appears to affect insulin sensitivity and serum cHDL level.     

Evolution and physiological consequences of de-alation in crickets

Wing shedding or de-alation is a common phenomenon among crickets. Its significance and effects on other traits were examined based on the results from experiments using artifical or natural de-alation. Artificial de-alation at adult emergence induces rapid egg production and flight muscle histolysis in several species examined. However, natural de-alation does not always shorten the pre-ovipositional period because it does not occur immediately after adult emergence and because oviposition starts before de-alation. In some cases, naturally de-alated females produce more eggs than to intact females during early adult life, but peak ovipositing activity occurs before de-alation. Therefore, retention of the hindwings does not suppress high ovipositing activity in such cases. It appears that de-alation is a result rather than a causal factor in ending migration. Ovarian development and flight muscle histolysis, which can be stimulated by de-alation, are controlled by the jevenile hormone, but the mechanism inducing de-alation remains unknown. The possible factors leading to the evolution of de-alation are discussed.     

DNA分子水平的遗传多态性研究进展

随着分子生物学和遗传学的迅速发展,多态性的研究已经从形态水平深入到分子水平。DNA分子水平的遗传多态性越来越受到重视。本文系统地了分析了DNA多态性的发现﹑分类﹑特点以及检测方法,介绍了DNA多态性在医学、法医学、人类学方面的应用。DNA多态性是生物多样性的基础,随着对DNA多态性更深入的研究,DNA多态性将会更好地服务于遗传学﹑生物医学和法医学的研究和实际应用。     

The physiological costs of flight capability in wing-dimorphic crickets

Nutritional indices, triglyceride levels and flight muscle developmental profiles were compared between long-winged (LW) and short-winged (SW; flightless) morphs of the cricketsGryllus rubens Scudder andG. firmus Scudder. This was done to identify potential physiological costs of flight capability in adults. The LW morph of each species converted a lower proportion of assimilated nutrients into biomass (reduced ECD) than did the SW morph. This documents increased respiratory metabolism in the LW morph. Triglyceride concentration was higher in LW vs. SW adults. This suggests that the elevated respiration in the LW morph may be at least partially due to the increased biosynthesis of this high energy substance. Preliminary data indicate higher respiration rates of LW functional vs. SW vestigial flight muscles. Collectively, these data suggest that the energetic cost of flight capability in adults results from biosynthesis of triglyceride flight fuel and flight muscle maintenance but not flight muscle growth. No flight muscle growth was observed in adults.     

Identification of quantitative trait loci for canine hip dysplasia by two sequential multipoint linkage analyses

Canine hip dysplasia (CHD) is characterized by hip laxity and subluxation that can lead to hip osteoarthritis. Studies have shown the involvement of multiple genetic regions in the expression of CHD. Although we have associated some variants in the region of fibrillin 2 with CHD in a subset of dogs, no major disease-associated gene has been identified. The focus of this study is to identify quantitative trait loci (QTL) associated with CHD. Two sequential multipoint linkage analyses based on a reversible jump Markov chain Monte Carlo approach were applied on a cross-breed pedigree of 366 dogs. Hip radiographic trait (Norberg Angle, NA) on both hips of each dog was tested for linkage to 21,455 single nucleotide polymorphisms across 39 chromosomes. Putative QTL for the NA was found on 11 chromosomes (1, 2, 3, 4, 7, 14, 19, 21, 32, 36, and 39). Identification of genes in the QTL region(s) can assist in identification of the aberrant genes and biochemical pathways involving hip dysplasia in both dogs and humans.     

甘肃省汉、藏族ApoB位点遗传多态性的初步研究

用Amp-FLP分析技术对110份甘肃省汉族、93份藏族ApoB位点的等位基因进行多态性分析,建立了2个民族正常群体ApoB位点基因的遗传学参数,分析了他们在等位基因分布上的差异,并比较了他们与成都汉族之间在等位基因的数目和频率分布上的差异性.结果表明甘肃汉族与成都汉、藏族之间以及藏族与成都汉族之间都存在着显著性差异(P<0.01),支持了将现代中国人分为北部类型、南部类型和藏彝走廊类型的观点.     

A Bayesian False Discovery Rate for Multiple Testing

Case-control studies of genetic polymorphisms and gene-environment interactions are reporting large numbers of statistically significant associations, many of which are likely to be spurious. This problem reflects the low prior probability that any one null hypothesis is false, and the large number of test results reported for a given study. In a Bayesian approach to the low prior probabilities, Wacholder et al. (2004) suggest supplementing the p-value for a hypothesis with its posterior probability given the study data. In a frequentist approach to the test multiplicity problem, Benjamini & Hochberg (1995) propose a hypothesis-rejection rule that provides greater statistical power by controlling the false discovery rate rather than the family-wise error rate controlled by the Bonferroni correction. This paper defines a Bayes false discovery rate and proposes a Bayes-based rejection rule for controlling it. The method, which combines the Bayesian approach of Wacholder et al. with the frequentist approach of Benjamini & Hochberg, is used to evaluate the associations reported in a case-control study of breast cancer risk and genetic polymorphisms of genes involved in the repair of double-strand DNA breaks.     

程序设计方法SPP与OOP的比较

就特性、开发步骤、综合性能三方面分析比较了传统的结构化程序设计方法 ( SPP)与面向对象程序设计方法 ( OOP)的异同点 ,并指出了在学习和应用中应注意的问题