3种急性非淋巴细胞白血病血细胞分析中血小板平均体积和血小板体积分布宽度变化的临床意义

目的探讨血小板平均体积(MPV)和血小板体积分布宽度(PDW)在(M2、M3、M5)3种急性非淋巴细胞白血病(ANLL)疾病诊疗中的临床意义。方法采用SysmexNE—1500全自动血细胞分析仪对(M2、M3、M5)3种ANLL患者的MPV和PDW进行测定。并以128名健康人的MPV和PDW的结果作对照。结果疾病组与健康对照组的MPV和PDW的结果差异有统计学意义,MPV(P<0.05)、PDW(P<0.01)。结论MPV和PDW在(M2、M3、M5)3种ANLL疾病的治疗过程监测和预后效果追踪都有着重要的临床意义。     

福建省城乡中老年人群恒牙缺失情况调查

目的了解福建省中老年人群恒牙缺失的现状,为防治工作提供参考依据。方法采用多阶段、分层、等容量、随机抽样的方法对福建省中老年人恒牙缺失情况进行抽样调查。结果福建省城市地区中年人群的失牙平均数高于农村地区,牙列完整率则低于农村地区,男女人群之间差别无统计学意义。城市地区老年人群失牙平均数也均高于农村地区,老年女性的失牙平均数高于老年男性。老年人各牙位的失牙率均明显高于中年人,磨牙的失牙率最高,尖牙的失牙率最低。结论应加强口腔健康教育和保健的力度,尤其是老年人群,以避免恒牙缺失及失牙造成的功能障碍。     

妇幼医院无乳链球菌临床分布情况及药敏结果分析

目的了解妇幼医院无乳链球菌(GBS)感染的临床分布和药敏情况,为临床感染的预防及治疗提供依据。方法收集妇幼医院临床患者各类临床标本作无乳链球菌培养,经法国生物梅里埃VITEK-2全自动细菌鉴定分析仪进行鉴定和药敏分析的菌株171株。结果171株无乳链球菌株中血培养和泌尿生殖道分泌物标本中分离率最高,其次为脐带分泌物,临床分布以新生儿病区最高,其次为产科病区。药敏结果显示171株无乳链球菌对青霉素、氨苄青霉素敏感或中度敏感,对万古霉素、头孢菌素类抗生素均敏感,对四环素、克林霉素和红霉素的耐药率分别为100%、70.8%和55.6%。结论为防止无乳链球菌感染和新耐药菌株的出现,临床应重视对无乳链球菌的培养检测,并根据药敏结果选择抗生素进行预防和治疗。     

鄂西北十堰市斯氏狸殖吸虫病的分布及流行趋势分析

目的了解十堰地区斯氏狸殖吸虫病的分布及流行趋势,为制定防治策略提供科学依据。方法流行区采获溪蟹镜检囊蚴,检查动物体内斯氏狸殖吸虫的感染情况,收集既往资料与现场肺吸虫抗原和酶联免疫吸附试验调查的数据作统计,分析人群肺吸虫感染情况。观察人类行为、局部环境的改变对中间宿主孳生的影响。结果环境因素、特别是人类的行为对肺吸虫中间宿主的孳生有较大的影响,局部流行的区域已不具备中间宿主孳生所需的环境,水位的提升可形成更多的溪沟和山涧,有利于螺和溪蟹的孳生。调查显示人群感染率为23.37%,经防治人群肺吸虫和中间宿主囊蚴感染率都有较大幅度降低。结论鄂西北地区作为斯氏肺吸虫病的流行区,原有的部分斯氏狸殖吸虫第二中间宿主孳生环境己发生了改变,动物宿主肺吸虫囊蚴的感染率及人群感染率呈现逐渐下降的趋势。同时随着退耕还林的实施,区域生态环境将得到进一步改善,适合中间宿主的繁殖和野生动物的活动,肺吸虫病的疫源地也将会长期存在。     

A new generalization of Weibull distribution with application to a breast cancer data set

In this article, we propose a new generalization of the Weibull distribution, which incorporates the exponentiated Weibull distribution introduced by Mudholkar and Srivastava (IEEE Trans. Reliab. 1993; 42 :299–302) as a special case. We refer to the new family of distributions as the beta‐Weibull distribution. We investigate the potential usefulness of the beta‐Weibull distribution for modeling censored survival data from biomedical studies. Several other generalizations of the standard two‐parameter Weibull distribution are compared with regards to maximum likelihood inference of the cumulative incidence function, under the setting of competing risks. These Weibull‐based parametric models are fit to a breast cancer data set from the National Surgical Adjuvant Breast and Bowel Project. In terms of statistical significance of the treatment effect and model adequacy, all generalized models lead to similar conclusions, suggesting that the beta‐Weibull family is a reasonable candidate for modeling survival data. Copyright © 2009 John Wiley & Sons, Ltd.     

Sample size for two‐stage studies with maintenance therapy

An adaptive treatment strategy (ATS) is defined as a sequence of treatments and intermediate responses. ATS' arise when chronic diseases such as cancer and depression are treated over time with various treatment alternatives depending on intermediate responses to earlier treatments. Clinical trials are often designed to compare ATSs based on appropriate designs such as sequential randomization designs. Although recent literature provides statistical methods for analyzing data from such trials, very few articles have focused on statistical power and sample size issues. This paper presents a sample size formula for comparing the survival probabilities under two treatment strategies sharing same initial, but different maintenance treatment. The formula is based on the large sample properties of inverse‐probability‐weighted estimator. Simulation study shows strong evidence that the proposed sample size formula guarantees desired power, regardless of the true distributions of survival times. Copyright © 2009 John Wiley & Sons, Ltd.     

A computationally efficient hypothesis testing method for epistasis analysis using multifactor dimensionality reduction

Multifactor dimensionality reduction (MDR) was developed as a nonparametric and model‐free data mining method for detecting, characterizing, and interpreting epistasis in the absence of significant main effects in genetic and epidemiologic studies of complex traits such as disease susceptibility. The goal of MDR is to change the representation of the data using a constructive induction algorithm to make nonadditive interactions easier to detect using any classification method such as naïve Bayes or logistic regression. Traditionally, MDR constructed variables have been evaluated with a naïve Bayes classifier that is combined with 10‐fold cross validation to obtain an estimate of predictive accuracy or generalizability of epistasis models. Traditionally, we have used permutation testing to statistically evaluate the significance of models obtained through MDR. The advantage of permutation testing is that it controls for false positives due to multiple testing. The disadvantage is that permutation testing is computationally expensive. This is an important issue that arises in the context of detecting epistasis on a genome‐wide scale. The goal of the present study was to develop and evaluate several alternatives to large‐scale permutation testing for assessing the statistical significance of MDR models. Using data simulated from 70 different epistasis models, we compared the power and type I error rate of MDR using a 1,000‐fold permutation test with hypothesis testing using an extreme value distribution (EVD). We find that this new hypothesis testing method provides a reasonable alternative to the computationally expensive 1,000‐fold permutation test and is 50 times faster. We then demonstrate this new method by applying it to a genetic epidemiology study of bladder cancer susceptibility that was previously analyzed using MDR and assessed using a 1,000‐fold permutation test. Genet. Epidemiol. 2008. © 2008 Wiley‐Liss, Inc.     

广州地区新型甲型H1N1流感患者病毒RNA检出率与病程关系的研究

目的 探讨2009年新型甲型H1N1流感患者病毒RNA检出率与人群年龄分布和病程变化的关系.方法 选取广州地区新型甲型H1N1临床病例共248例,对151例进行病程动态咽拭子采样833份,统计分析患病人群年龄分布和采用荧光定量RT-PCR方法对不同病程的患者咽拭子标本进行甲型HINl流感病毒RNA的检测,并采用趋势x~2检验探讨标本阳性率与不同发病时间的关系.结果 发病人群以青壮年为主,主要集中在10～20岁(57.26%)和20～30岁(22.18%)两个年龄段.对咽拭子标本阳性率随发病时间的变化进行趋势x~2结果显示标本阳性率随着病程的延长而下降(x~2=9.784,P=0.002).讨论此次研究表明新型H1N1流感患者主要集中在青壮年人群中,且有最长可达10天以上的病程,标本阳性率随着病程的延长而下降.

Abstract：

Objective To study the relation of the detection rates of the novel influenza virus A/H1N1 RNA in clinically confirmed patients in the 2009 pandemic with the age distribution of the patients and the disease course. Methods A total of 151 clinical patients with H1N1 infection were enrolled in this study, from whom 833 dynamic throat swab samples were obtained for detecting the H1N1 RNA using real-time PCR. A statistical analysis of the age distribution was performed among the patients with different disease courses. Chi-square for trend test was used to study the correlation between the detection rates of H1N1 RNA and the time of disease onset. Results The majority of patients were young with their ages ranging from 10 to 20 years (57.26%) and 20 to 30 years (22.18%). Chi-square for trend test revealed that the positivity rates of the throat swabs in the patients decreased with the prolongation of the disease course (x~2=9.784, P=0.002). Conclusion Most of the H1N1 patients are young within the age range of 10-30 years, and the longest disease course can exceed 10 days. The positivity rates of throat swabs from the H1N1 patients decreases with the prolongation of the disease course.     

某校2008级留学生医学微生物学与免疫学期末考试成绩分析

目的分析2008级留学生医学微生物学与免疫学期末考试成绩并提出改进教学质量的策略。方法对全年级202名学生的期末考试试卷进行统计分析。结果考试成绩基本呈正态分布,平均成绩为72.16分,标准差为11.70分,试卷信度为0.83。结论该试卷能客观反映学生对课程的掌握程度,投射出教学中的一些问题,并据此提出今后教学过程中具体改进意见和措施。     

2005-2007年大连市蜚蠊种群分布及生态习性调查

目的掌握大连市蜚蠊种群分布和季节消长等动态变化规律。方法统一使用粘捕盒诱捕。结果全市共有3种蜚蠊分布,其中德国小蠊为优势种,占96．89％;日本大蠊和黑胸大蠊所占比例较小,分别为3．02％和0．09％。蜚蠊以7—10月为其活动高峰期。行业分布以农贸市场密度最高,其他依次为居民区、餐饮业、宾馆、医院。结论德国小蠊现已成为大连市主要优势种,应将其列为今后防治的重点。