Circadian Rhythms of Heart Rate Variability in Hypertrophic Cardiomyopathy

Background: It has been hypothesized that an interaction between sympathetic nervous activity and an abnormal myocardium plays a role in the development and progression of hypertrophic cardiomyopathy (HCM). Methods: In the present study we investigated cardiac autonomic function by 24-hour spectral analysis of heart rate variability (HRV) in 18 patients with HCM, without evidence of heart failure, and 18 controls of similar age. Results: We found a significant reduction of 24 hour variance in HCM patients relative to controls (15,000 ± 9480 ms² vs 24,720 ± 12,450 ms² respectively; p < 0.05). Moreover, a loss of the expected day-night changes in the low frequency (LF) spectral component (expressed in normalized units), and LF/HF ratio (HF; high frequency component) were observed in HCM patients. Decreased day-night changes in LF/HF ratio were previously reported in patients with mild hypertension, uncomplicated coronary disease, and after myocardial infarction, conditions in which it seems to exist a higher than normal sympathetic activity. No significant correlations were found between HRV indices and echocardiographic standard measures of systolic and diastolic function parameters. Conclusions: These data are consistent with the presence of an alteration in neural modulation of heart period in HCM patients, noninvasively detectable by continuous 24 hour HRV analysis.     

三维能量多普勒超声对子宫内膜癌的诊断价值

目的探讨三维能量多普勒超声对子宫内膜癌的诊断价值。方法应用三维能量多普勒超声观察199例阴道流血患者(根据病理结果分为良性病变组162例、子宫内膜癌组12例、月经紊乱组25例)和30例绝经期子宫内膜患者(绝经组),对比分析各组子宫内膜血流动力学参数:收缩期峰值流速(Vmax)、阻力指数(RI)、搏动指数(PI)、血管形成指数(VI)、血流指数(FI)、血管形成-血流指数(VFI)。结果良性病变组、子宫内膜癌组和月经紊乱组Vmax比较差异无统计学意义;子宫内膜癌组RI、PI与良性病变组和月经紊乱组比较差异均有统计学意义(均P0.01);子宫内膜癌组VI、FI、VFI值均高于良性病变组、月经紊乱组和绝经组,差异均有统计学意义(均P0.01);良性病变组VI、FI、VFI值均高于月经紊乱组和绝经组,差异均有统计学意义(均P0.05);月经紊乱组VI、FI、VFI值均高于绝经组,差异均有统计学意义(均P0.05)。结论三维能量多普勒超声能有效鉴别子宫内膜癌、内膜良性病变和正常内膜,对早期检出子宫内膜癌有重要临床应用价值。     

Bayesian probability of success for clinical trials using historical data

Developing sophisticated statistical methods for go/no‐go decisions is crucial for clinical trials, as planning phase III or phase IV trials is costly and time consuming. In this paper, we develop a novel Bayesian methodology for determining the probability of success of a treatment regimen on the basis of the current data of a given trial. We introduce a new criterion for calculating the probability of success that allows for inclusion of covariates as well as allowing for historical data based on the treatment regimen, and patient characteristics. A new class of prior distributions and covariate distributions is developed to achieve this goal. The methodology is quite general and can be used with univariate or multivariate continuous or discrete data, and it generalizes Chuang‐Stein's work. This methodology will be invaluable for informing the scientist on the likelihood of success of the compound, while including the information of covariates for patient characteristics in the trial population for planning future pre‐market or post‐market trials. Copyright © 2014 John Wiley & Sons, Ltd.     

On generalized fixed sequence procedures for controlling the FWER

Testing a sequence of pre‐ordered hypotheses to decide which of these can be rejected or accepted while controlling the familywise error rate (FWER) is of importance in many scientific studies such as clinical trials. In this paper, we first introduce a generalized fixed sequence procedure whose critical values are defined by using a function of the numbers of rejections and acceptances, and which allows follow‐up hypotheses to be tested even if some earlier hypotheses are not rejected. We then construct the least favorable configuration for this generalized fixed sequence procedure and present a sufficient condition for the FWER control under arbitrary dependence. Based on the condition, we develop three new generalized fixed sequence procedures controlling the FWER under arbitrary dependence. We also prove that each generalized fixed sequence procedure can be described as a specific closed testing procedure. Through simulation studies and a clinical trial example, we compare the power performance of these proposed procedures with those of the existing FWER controlling procedures. Finally, when the pairwise joint distributions of the true null p‐values are known, we further improve these procedures by incorporating pairwise correlation information while maintaining the control of the FWER. Copyright © 2015 John Wiley & Sons, Ltd.     

A power series beta Weibull regression model for predicting breast carcinoma

The postmastectomy survival rates are often based on previous outcomes of large numbers of women who had a disease, but they do not accurately predict what will happen in any particular patient's case. Pathologic explanatory variables such as disease multifocality, tumor size, tumor grade, lymphovascular invasion, and enhanced lymph node staining are prognostically significant to predict these survival rates. We propose a new cure rate survival regression model for predicting breast carcinoma survival in women who underwent mastectomy. We assume that the unknown number of competing causes that can influence the survival time is given by a power series distribution and that the time of the tumor cells left active after the mastectomy for metastasizing follows the beta Weibull distribution. The new compounding regression model includes as special cases several well‐known cure rate models discussed in the literature. The model parameters are estimated by maximum likelihood. Further, for different parameter settings, sample sizes, and censoring percentages, some simulations are performed. We derive the appropriate matrices for assessing local influences on the parameter estimates under different perturbation schemes and present some ways to assess local influences. The potentiality of the new regression model to predict accurately breast carcinoma mortality is illustrated by means of real data. Copyright © 2015 John Wiley & Sons, Ltd.     

3D-CPA、HR-HPV及TCT联合检测对高级别宫颈上皮内瘤变及早期宫颈癌的诊断价值

目的:探讨经阴道三维彩色血管能量成像(3D-CPA)技术、高危型人乳头瘤病毒(HR-HPV)及液基细胞学(TCT)联合检测对高级别宫颈上皮内瘤变(CIN)及早期宫颈癌的诊断价值.方法:选取2012年6月～ 2014年12月在该院宫颈门诊就诊的患者为研究对象,分别接受3D-CPA、HR-HPV及TCT检查,以上3项指标任一阳性者行阴道镜下活检,病理诊断为金标准.选取慢性宫颈炎52例、低级别CIN 50例、高级别CIN 80例、早期宫颈癌(Ⅰa-Ⅱa)35例进行分析.评价3种筛查方法单独或联合筛查共5种方案的灵敏度、特异度、诊断符合率及约登指数.结果:早期宫颈癌组血管形成指数(VI)大于高级别CIN组及低级别CIN组,差异均有统计学意义(P＜0.01);3组血管形态及分级比较,差异均有统计学意义(P＜0.05);3种筛查方法单独筛查发现:灵敏度最高为HPV(89.70％),特异度最高为VI(80.77％),诊断符合率最高为HPV(85.25％).HPV+TCT与HPV+TCT+VI联合筛查发现:灵敏度和特异度最高均为三者联合筛查,灵敏度为96.36％,特异度为75％,诊断符合率为91.24％,约登指数最高为0.715.HPV16/18阳性患者宫颈癌组占94.29％,高级别CIN组占55.00％,低级别CIN组占21.57％.结论:3D-CPA、HR-HPV及TCT联合检测可提高宫颈病变筛查的灵敏度及准确度,应加强对HPV16/18阳性患者的筛查.     

结肠镜术前肠道准备三种方案清洁效果的对比研究

目的 比较临床上常用的3种肠道准备方案的肠道清洁效果,寻求最快速有效的肠道准备方案。方法 对2017年5月至6月在江苏省人民医院消化科病房拟行肠镜检查的患者77例行不同方案的肠道准备,并按不同方案分为3组。第1组22例口服聚乙二醇电解质散2 L+乳果糖口服液6包单次服用;第2组31例口服聚乙二醇电解质散2 L+乳果糖口服液6包分次服用;第3组24例口服聚乙二醇电解质散3 L。观察患者服药后肠道准备的效果和不良反应情况。结果 肉眼观察肠道清洁有效的例数,第2组明显多于其他两组（P＜0.05）;肠镜下渥太华量表评分显示,第1组和第2组对比差异无统计学意义（P＞0.05）,第2组和第3组对比,差异有统计学意义（P＜0.05）,说明渥太华评分标准判断下,第2组优于第3组;服药不良反应率比较,第2组明显优于其他两组（P＜0.05）。结论 采用聚乙二醇电解质散2 L+乳果糖口服液6包分次服用方案进行肠道准备,具有较好的肠道清洁效果,不良反应少,患者更易接受。     

基于CNFET的三值逐次逼近ADC设计

模数转换器(Analog-to-Digital Converter,ADC)是片上集成系统的关键部件,通过对逐次逼近逻辑电路和三值逻辑原理的研究,提出了一种基于碳纳米场效应晶体管(Carbon Nanotube Field Effect Transistor,CNFET)的三值逐次逼近ADC设计方案。该方案首先控制三值电容阵列的底板电压,逐次逼近其模拟量值,产生由高位到低位的二值信号,然后由编码器将二值转换为三值信号,完成整个转换过程,最后实验证明了所设计的电路逻辑功能正确,并具有明显的高速、低功耗特性。