ARIMA模型在疟疾发病率预测中的应用

目的 目的 应用自回归求和移动平均模型 （Autoregressive Integrated Moving Average Model, ARIMA） 进行湖北省本地 疟疾发病率预测。 方法 方法 应用SPSS 13.0软件对2004-2009年湖北省本地疟疾发病率构建ARIMA模型, 并以2010年发 病率数据检验模型, 评价模型拟合及预测效果。 结果 结果 经检验确认ARIMA （1,1,1） （1,1,0） 12模型拟合效果相对最 优, AIC=76.085, SBC=84.395, 发病率实际值均在预测值的95%可信区间内, 表明模型预测效果较好。 结论 结论 ARIMA模 型可对湖北省本地疟疾发病率进行较好的拟合和预测。     

基于周期分解的ARIMA模型在甲肝发病率预测中的应用

摘要:目的　探讨基于周期分解的ARIMA模型在我国甲肝月发病率预测中的应用,并比较其与SARIMA模型的预测效果。方法　收集2004年1月-2014年12月我国甲肝月发病率资料,用SPSS13.0分别拟合两种模型,并用2014年的数据评价模型的预测效果。结果　基于周期分解的ARIMA模型的拟合及预测的MRD,MER,MSE和MAE分别为4.4691,0.0446,0.0002,0.0092;4.1310,0.0415,0.0001,0.0066。SARIMA模型的拟合及预测的MRD,MER,MSE和MAE分别为7.2979,0.0781,0.0003,0.0185;6.4407,0.0708,0.0002,0.0110。结论　基于周期分解的ARIMA模型拟合和预测效果优于SARIMA模型。它可以提高预测的精度,具有较好的应用价值。     

SARIMA模型用于新疆乙肝发病率预测的探讨

摘要:目的　探讨SARIMA模型用于新疆乙肝月发病率预测的可行性,为制定防控策略提供科学参考。方法　采用带有季节性的自回归移动平均模型（SARIMA）,分析将其用于新疆乙肝发病率预测的可行性,对模型进行参数估计及残差检验,根据AIC及BIC准则确定最适合的SARIMA模型,讨论该模型的拟合及预测效果。结果　SARIMA（1,1,2）（0,1,0）12模型很好地拟合了新疆乙肝月发病率变化规律,模型预测值与实际值间的相对误差及均方误差较小。结论　SARIMA（1,1,2）（0,1,0）12模型能够较好地用于新疆乙肝月发病率预测,可为新疆的乙肝防控提供科学参考。     

The “highs and lows” of the human brain on dopaminergics: Evidence from neuropharmacology

Rewards are appetitive events that elicit approach. Ground-breaking findings from neurophysiological experiments in animals, alongside neuropharmacology and neuroimaging research in human samples have identified dopamine as the main neurochemical messenger of global reward processing in the brain. However, dopamine’s contribution to the different components of reward processing remains to be precisely defined. To facilitate the informed design and interpretation of reward studies in humans, we have systematically reviewed all existing human pharmacological studies investigating how drug manipulation of the dopamine system affects reward-related behaviour and its neural correlates. Pharmacological experiments in humans face methodological challenges in terms of the: 1) specificity and safety of the available drugs for administration in humans, 2) uncertainties about pre- or post-synaptic modes of action, and 3) possible interactions with inter-individual neuropsychological or genotypic variables. In order to circumvent some of these limitations, future research should rely on the combination of different levels of observation, in integrative pharmaco-genetics-neurobehavioral approaches, to more completely characterize dopamine’s role in both general and modality-specific processing of reward.     

Score model for predicting acute-on-chronic liver failure risk in chronic hepatitis B

AIM: To establish a clinical scoring model to predict risk of acute-on-chronic liver failure(ACLF) in chronic hepatitis B(CHB) patients.METHODS: This was a retrospective study of 1457 patients hospitalized for CHB between October 2008 and October 2013 at the Beijing Ditan Hospital, Capital Medical University, China. The patients were divided into two groups: severe acute exacerbation(SAE) group(n = 382) and non-SAE group(n = 1075). The SAE group was classified as the high-risk group based on the higher incidence of ACLF in this group than in the non-SAE group(13.6% vs 0.4%). Two-thirds of SAE patients were randomly assigned to risk-model derivation and the other one-third to model validation. Univariate risk factors associated with the outcome were entered into a multivariate logistic regression model for screening independent risk factors. Each variable was assigned an integer value based on the regression coefficients, and the final score was the sum of these values in the derivation set. Model discrimination and calibration were assessed using area under the receiver operating characteristic curve and the Hosmer-Lemeshow test. RESULTS: The risk prediction scoring model includedthe following four factors: age ≥ 40 years, total bilirubin ≥ 171 μmol/L, prothrombin activity 40%-60%, and hepatitis B virus DNA 107 copies/m L. The sum risk score ranged from 0 to 7; 0-3 identified patients with lower risk of ACLF, whereas 4-7 identified patients with higher risk. The Kaplan-Meier analysis showed the cumulative risk for ACLF and ACLF-related death in the two risk groups(0-3 and 4-7 scores) of the primary cohort over 56 d, and log-rank test revealed a significant difference(2.0% vs 33.8% and 0.8% vs 9.4%, respectively; both P 0.0001). In the derivation and validation data sets, the model had good discrimination(C index = 0.857, 95% confidence interval: 0.800-0.913 and C index = 0.889, 95% confidence interval: 0.820-0.957, respectively) and calibration demonstrated by the Hosmer-Lemeshow test(χ2 = 4.516, P = 0.808 and χ2 = 1.959, P = 0.923, respectively).CONCLUSION: Using the scoring model, clinicians can easily identify patients(total score ≥ 4) at high risk of ACLF and ACLF-related death early during SAE.     

聚乙二醇干扰素α-2a联合阿德福韦酯治疗HBeAg阳性慢性乙型肝炎疗效预测因素分析

目的 分析聚乙二醇干扰素（PEG-IFNα-2a）联合阿德福韦酯（ADV）治疗HBeAg阳性慢性乙型肝炎（CHB）患者48 w时的疗效及其预测因素。方法 将196例HBeAg阳性CHB患者分为PEG-IFNα-2a治疗64例,ADV治疗66例和PEG-IFNα-2a联合ADV治疗66例,疗程均为48 w。采用ELISA法检测INF-γ和IL-10;采用Achitect（Abbott）微粒子化学发光免疫分析法检测HBeAg定量。结果 在治疗48 w时,联合组HBV DNA阴转率、HBeAg阴转率、HBeAg转换率和ALT复常率分别为74.2%、24.2%、48.5%和80.3%,显著高于干扰素组（53.1%、10.9%、29.7%和54.7%,P<0.05）和阿德福韦组（62.1%、13.6%、9.1%和65.2%,P<0.05）;联合组INF-γ水平为（45.3±11.3） pg/ml,显著高于干扰素组[（37.1±10.3） pg/ml,P<0.05]和阿德福韦组[（36.3±11.5） pg/ml,P<0.05];联合组IL-10水平为（10.3±14.6） pg/ml,显著低于干扰素组[（17.1±11.3） pg/ml,P<0.05]和阿德福韦组[（18.3±10.5） pg/ml,P<0.05];联合组治疗48 w时HBeAg血清学转换与治疗24 w时HBeAg水平下降的百分比有关,即治疗24 w时HBeAg水平较基线下降大于89.1%的阳性预测值为88.7%,阴性预测值（NPV）为81.9%,灵敏度为83.1%,特异度为87.9%。结论 PEG-IFNα-2a联合ADV治疗HBeAg阳性慢性乙型肝炎能增强机体细胞免疫应答,疗效优于单药治疗,其中治疗24 w时HBeAg下降的百分比可预测48 w时的疗效。     

Hazardous to your health: kinetic foundations of risk stratification and therapeutic triage

Background

Risk stratification is widely used in the prognostic assessment of patients with a variety of clinical disorders on the unquestioned assumption that the intensity of treatment should be proportionate to the threat of an adverse event over some finite period of time (risk). However, just as the physical trajectory of an object depends on its current magnitude of displacement (velocity) and the concurrent rate of change of that displacement (acceleration), the prognostic trajectory of a patient depends on the current magnitude of risk and the concurrent rate of change of that risk (hazard). Clinical risk stratification nevertheless relies only on the former.

Methods

We therefore integrated the quantitative assessment of risk and hazard by way of a kinetic model that characterizes the development of an adverse event as a series of exponential state-to-state transitions—from stable to unstable to event. This model serves to shift the clinical emphasis from prognosis (the assessment of risk) to treatment (the improvement in outcome). In this context, treatment is well advised (even in low-risk individuals) when the hazard is large (risk is rising), and is less well advised (even in high-risk individuals) when the hazard is small (risk is stable).

Results

The kinetic model outlined here thereby promises to supersede the superficial practice of risk stratification with a more sophisticated strategy of therapeutic triage that allows one to predict the incremental clinical benefit of alternative treatment strategies.     

Type 1 diabetes risk assessment: improvement by follow-up measurements in young islet autoantibody-positive relatives

Aims/hypothesis Combinations of autoantibody characteristics, including antibody number, titre, subclass and epitope have been shown to stratify type 1 diabetes risk in islet autoantibody-positive relatives. The aim of this study was to determine whether autoantibody characteristics change over time, the nature of such changes, and their implications for the development of diabetes.Methods Five-hundred and thirteen follow-up samples from 141 islet autoantibody-positive first-degree relatives were tested for islet autoantibody titre, IgG subclass, and GAD and IA-2 antibody epitope. All samples were categorised according to four risk stratification models. Relatives had a median follow-up of 6.8 years and 48 developed diabetes during follow-up. Survival analysis was used to determine the probability of change in risk category and of progression to diabetes.Results For each stratification model, the majority of relatives (71–81%) remained in the same risk category throughout follow-up. In the remainder, changes occurred both from lower to higher and from higher to lower risk categories. For all four models, relatives aged < 15 years were more likely to change risk category than those aged >15 years (0.001 < p < 0.03). Relatives whose autoantibody status changed from low- to high-risk categories had a higher risk of diabetes than relatives who remained in low-risk categories, and inclusion of autoantibody status during follow-up improved diabetes risk stratification in Cox proportional hazards models (p < 0.001).Conclusions/interpretation Changes in islet autoantibodies are relevant to pathogenesis, and are likely to signal alterations in the disease process. Detection of changes through follow-up measurement will improve diabetes risk stratification, particularly in young individuals.     

子痫前期预测的现状与展望

子痫前期(PE)是妇女孕期特发的多系统疾病,是导致孕产妇和围产儿患病和死亡的主要原因之一。临床发病多出现在妊娠20周以后,其主要临床表现血压升高、水肿、蛋白尿等与众多因素有关,如何从中找到准确预测PE的方法一直是人们研究的重点。本文对PE预测现状作一综述,并对以后的预测研究作一展望。     

Prediction in the timing of pursuit eye movement initiation revealed by cross-axis vestibular–pursuit training in monkeys

The smooth-pursuit system interacts with the vestibular system to maintain the image of a moving target on the fovea. Efficient tracking performance requires information about the velocity and the initiation of target motion. Previous studies in monkeys have shown that training with orthogonal pursuit and whole body rotation results in adapted eye movement direction during chair rotation. In addition, the latency of the pursuit shortens and initial eye velocity increases in a task-dependent manner. To examine whether these adapted eye movements are predictive pursuit, we studied whether our monkeys could predict the timing of smooth eye movement initiation during chair rotation. Two young Japanese monkeys were rotated horizontally in a trapezoidal waveform (20°/s, ±10°) with random inter-trial intervals. A laser spot was moved vertically with the same trajectory at a constant delay ranging from 100 to 700 ms after the onset of the chair motion. The monkeys were required to pursue the spot. After this training, the latencies of pursuit eye movements following the onset of chair motion were examined in the presence of the target motion. The target was also briefly (for 500–700 ms) extinguished at 80 ms after the onset of chair rotation. Pursuit eye movements after training were initiated before the onset of target motion and the latencies were proportional to the delays used for training. The latencies and response magnitudes of pursuit with or without target blanking were similar. The auditory–pursuit training did not induce an initial pursuit response similar to that induced by vestibular–pursuit training. These results indicate that smooth eye movements during the chair rotation after the vestibular–pursuit training included a predictive pursuit component. The monkeys’ estimate of the delays revealed by the latencies of pursuit was shorter by 22–36% than the actual delays.