Increase in Power through Multivariate Analyses

Power to detect genetic and environmental influences increases not only with sample size but also with the number of measurements through longitudinal and/or multivariate designs, if those measurements correlate with each other. Power simulations are presented for uni- through quadrivariate cases, with differing genetic and environmental parameters. Even though subject attrition is a problem for most longitudinal studies, the gain in power available may more than make up for this shortcoming in many situations. In terms of planning studies to examine genetic and environmental influences, power calculations should not only consider sample size but number of measurements on particular phenotypes and their intercorrelations.     

人机工程学工作分析方法在体力劳动负荷评价中的应用

对鞍钢耐火厂、炼钢厂22个工种分别进行体力劳动负荷的人机工程学分析及劳动强度测定。调查表明,两种方法所得结果基本一致,但人机工程学分析方法简便,易于基层单位推广应用。     

广东省SARS流行株M基因序列分析

目的：测定广东省不同流行时期13份SARS病毒(SARS CoV)标本的M基因序列，通过分析该基因序列的变异情况，初步了解广东省SARS病毒在流行过程中是否发生了变异。方法：提取病毒RNA，用M基因特异引物进行RT-PCR，将产物纯化后直接测定核苷酸序列。结果：13份标本M基因核苷酸序列同源性很高，为99．7％～100％，M基因核苷酸序列只在2个位点(80和203位)发生变异，1株80位点的变化引起编码的氨基酸从苯丙氨酸(F)变为半胱氨酸(C)，3株203位变化为无义突变。结论：M基因核苷酸序列变异不大，初期和后期M基因核苷酸序列与流行高峰期的毒株相差1个碱基，但氨基酸序列相同；从香港感染病人分离的1株病毒M基因与广东本地感染分离株存在1个氨基酸的差异。     

10个钨矿职工死因分析

对中南地区10个钨矿1972—1974年入矿(工龄至少1年)的在册职工28453人进行了队列研究。队列成员追访至1989年,死亡2870人,比全国居民死亡率计算的期望值略高(SMR=1.15,95％CI=1.11—1.19);主要是非恶性呼吸道疾病,特别是尘肺(SMR=66.79,95％CI=59.65—73.68)以及与呼吸道疾病相关的肺心病明显超高(SMR=8.19,95％CI=7.42—9.02),比全国居民死亡率高5倍。癌症死亡数在全死因中虽占第一位,但仅鼻咽癌轻度超高(SMR=1.73,95％CI=1.23—2.37),而肺癌死亡率明显偏低(SMR=0.53)。研究结果不支持矽肺与肺癌病因学相关的假说。     

用速率法测定尿NAG活性及其临床应用

本文报道用５５０型全自动生化分析仪，以速率法测定尿ＮＡＧ活性及本室尿ＮＡＧ活性的正常参考范围；并对可能影响尿ＮＡＧ活性的尿ＰＨ，尿素浓度等进行了干扰试验及分析。     

Second births among teenage mothers: program results and statistical methods

This paper uses survival analysis to examine three large-scale, multi-site, randomized, controlled programs that attempted to prevent or delay second births to teenagers. Statistically significant differences in the hypothesized direction were found between the intervention and the control groups in the Elmira and Memphis Home Visitation sites. No statistically significant differences in the hypothesized direction were found in the Teen Parent Welfare Demonstration overall or in any of its three sites or in all New Chance sites combined. Delaying second pregnancies among teenagers requires intensive efforts. Survival analysis is a more accurate and useful way of presenting program results than simple analysis of the proportion of women with a second birth.     

A new nematode, <Emphasis Type="Italic">Pongobius hugoti</Emphasis> gen. et sp. n. from the orangutan <Emphasis Type="Italic">Pongo abelii</Emphasis> (Primates: Hominidae)

Summary Light and scanning electron microscopical examination and molecular analysis of pinworm samples collected from the Sumatran orangutan (Pongo abelii) from Sumatra (Indonesia) revealed the presence of a new taxon, Pongobius hugoti gen. et sp. n. (Oxyuridae: Enterobiinae). The monotypic genus Pongobius is characterised by the presence of a triangular mouth, three rounded teeth and three chisel-like inner teeth in the buccal cavity, an oesophagus with a long pharyngeal part, corpus posteriorly slightly enlarged and continuing as a pyriform bulb, isthmus absent. These features differentiate P. hugoti from all members of the subfamily Enterobiinae. The male has a long caudal appendix (> 50% of total tail length). Molecular analysis of the new taxon is presented for more precise identification.     

Assessment of the Severity of Asthma in a Family Practice

The objective of this study was to evaluate clinical history and self-perception of severity as predictors of asthma severity. A short-term longitudinal study was conducted in a family practice in Melbourne, Australia, utilizing peak flow monitoring, medication diary, and self-administered asthma severity questionnaire. Seventy-two asthmatic subjects with a positive bronchodilator or exercise test, aged between 6 and 79 years, were studied. Symptom and treatment items were correlated with peak flow variability and minimal peak expiratory flow rate (PEFR). An asthma severity scale was generated using the partial credit version of Item Response Theory and the participants' severity scores were validated against lung function tests and medication usage. Quantitative modeling procedures were used to investigate the interrelationships of factors associated with peak flow variability. Severity scores demonstrated significant relationships with peak flow variability (partial r = 0.34) and treatment items. Self-perceived severity of asthma in the preceding 2 weeks showed significant association with peak flow variability (partial rho = 0.46) and minimal PEFR (rho = -0.41). The severity module of the Monash Respiratory Questionnaire is a valid and reliable instrument. The most important symptoms appear to be the frequency of use of bronchodilator and frequency of nocturnal attacks. A carefully structured clinical history in conjunction with the peak flow criteria of variability and minimal peak flow rate would be appropriate in the evaluation of asthma severity. Patients' self-perception of the severity of their asthma needs further evaluation.     

儿童智商与父母智商的相关性

目的：通过对儿童智商（IQ）与父母亲IQ和IQ分项相关研究，探讨儿童IQ和父母亲IQ的深层关系。方法：在合肥市某中学、小学和幼儿园，分别按年龄和性别分层，随机抽取4-14岁健康儿童206名及其父母作为研究对象，应用韦氏智力量表（成人和儿童）测定儿童和其父母的IQ，填写自编的影响儿童智力发育因素调查问卷。最后在考虑儿童的年龄、性别、克托莱指数（Quetelet index）和是否独生子女等可能混杂因素下将儿童的总IQ、语言IQ和操作IQ与其父母的总IQ、语言IQ、操作IQ和IQ分项进行多元逐步回归分析。结果：按F〉2．0标准，儿童总IQ与父母亲总IQ成正相关（偏相关系数分别为0．50和0．22）；儿童语言IQ与母亲算术、母亲知识、父亲算术、父亲拼物成正相关（偏相关系数0.23-0．37）；儿童操作IQ和母亲积木图案、母亲拼物和父亲拼物成正相关（偏相关系数0．31-0．50）。结论：父母亲的总IQ和父母IQ分项中的算术、拼物、积木图案和知识等对儿童总IQ、语言IQ和操作IQ影响最大。     

Sperm ubiquitination positively correlates to normal morphology in human semen

BACKGROUND: Global ubiquitination in human semen has been found to negatively correlate with standard semen parameters, indicating that ubiquitination can be considered a marker of poor semen quality. However, the inclusion of all semen components in the analysis may be misleading on the biological significance of ubiquitination of sperm cells. We have recently demonstrated the variable presence of bodies of different size, with the highest concentration in oligoasthenoteratozoospermia. The purpose of the present study was to evaluate the relationship between ubiquitination and standard semen parameters, after distinguishing between ubiquitinated sperm and bodies in each sample. METHODS: Ubiquitination was evaluated by flow cytometric sperm ubiquitin tag immunoassay (SUTI) in sperm samples from 45 subjects. Semen analysis was performed according to WHO (1999) guidelines. RESULTS: When only ubiquitinated sperm were considered, a positive correlation with number, motility and normal morphology was found. When correlation was evaluated considering the percentage of ubiquitinated bodies, a negative correlation was found with good semen quality. CONCLUSIONS: Results indicate that the negative correlations previously found between global semen ubiquitination and parameters of semen analysis are mainly driven by components other than sperm. The positive correlation between sperm ubiquitination and good quality parameters suggests a previously unrecognized role for sperm ubiquitination.