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1.
In clinical and epidemiological studies, there is a growing interest in studying the heterogeneity among patients based on longitudinal characteristics to identify subtypes of the study population. Compared to clustering a single longitudinal marker, simultaneously clustering multiple longitudinal markers allow additional information to be incorporated into the clustering process, which reveals co-existing longitudinal patterns and generates deeper biological insight. In the current study, we propose a Bayesian consensus clustering (BCC) model for multivariate longitudinal data. Instead of arriving at a single overall clustering, the proposed model allows each marker to follow marker-specific local clustering and these local clusterings are aggregated to find a global (consensus) clustering. To estimate the posterior distribution of model parameters, a Gibbs sampling algorithm is proposed. We apply our proposed model to the primary biliary cirrhosis study to identify patient subtypes that may be associated with their prognosis. We also perform simulation studies to compare the clustering performance between the proposed model and existing models under several scenarios. The results demonstrate that the proposed BCC model serves as a useful tool for clustering multivariate longitudinal data.  相似文献   
2.
目的观察芪莲化积合剂对肝癌H22荷瘤小鼠的抗肿瘤作用。方法建立肝癌H22荷瘤小鼠实体瘤模型,将24只小鼠分为3组,对照组(生理盐水组)、芪莲化积合剂组和5-氟脲嘧啶(5-Fu)组各8只。通过测定荷瘤小鼠的瘤重、抑瘤率观察芪莲化积合剂剂对肿瘤生长的影响,采用RT-PCR技术检测miRNA122的表达情况。结果芪莲化积合剂能使肝癌H22荷瘤小鼠的瘤重减少,显著低于对照组(P<0.05);胸腺指数、脾指数的比较,芪莲化积合剂较对照组明显升高(P<0.05);在miRNA122的表达上,芪莲化积合剂较对照组明显升高(P<0.05)。结论芪莲化积合剂具有明显的抗肿瘤作用,其作用机制可能与miRNA122的表达有关。  相似文献   
3.
目的:观察清热化湿通腑汤联合奥曲肽治疗急性胰腺炎(AP)患者的效果。方法:选取86例AP患者为研究对象,按照随机数字表法分为对照组与研究组各43例。对照组经静脉注射奥曲肽治疗,研究组在对照组基础上联合清热化湿通腑汤治疗。比较两组疗效、症状缓解时间、炎性因子[白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、超敏C反应蛋白(hs-CRP)]水平。结果:研究组治疗总有效率高于对照组,差异有统计学意义(P<0.05);研究组治疗后胃肠功能恢复时间、血淀粉酶恢复时间、尿淀粉酶恢复时间、体温恢复时间均短于对照组,IL-6、TNF-α、CRP水平均低于对照组,差异有统计学意义(P<0.05)。结论:清热化湿通腑汤联合奥曲肽治疗AP患者,可提高治疗总有效率,缩短症状缓解时间,以及降低炎性因子水平,效果优于单纯奥曲肽治疗。  相似文献   
4.
目的 观察消瘤通腑散膏摩防治化学治疗后消化道反应的疗效。方法 将60例化学治疗患者随机分为治疗组和对照组各30例,治疗组在化学治疗期间使用消瘤通腑散膏摩联合常规西医对症处理,对照组仅予常规西医对症处理,比较两组患者化学治疗后恶心、呕吐及便秘的情况。结果 治疗组在延迟性呕吐观察期总有效率高于对照组(P<0.05),且可以降低恶心、呕吐发生的程度(P<0.05),但在急性呕吐观察期优势不明显(P>0.05)。治疗组防治化学治疗后便秘的有效率高于对照组,差异有统计学意义(P<0.05)。结论 消瘤通腑散膏摩可以有效改善化学治疗后的延迟性呕吐及便秘症状,提高患者的生活质量。  相似文献   
5.
目的:探讨应用中药通腑承气汤加减方治疗术后早期炎症性肠梗阻的临床疗效。方法:选取本院胃肠外科2018年3月—2020年3月84例术后早期炎症性肠梗阻患者,随机分为常规组与中药组,每组42例。对比两组疗效、胃肠功能康复与不良反应及治疗前后血清炎性因子指标[超敏C反应蛋白(hsCRP)、肿瘤坏死因子-α(TNF-α)、白细胞介素-8(IL-8)、降钙素原(PCT)]。结果:治疗后,中药组临床总疗效88.10%(37/42),显著高于常规组71.43%(30/42),常规组和中药组通腑承气汤组肠鸣音恢复、腹部症状(腹痛腹胀)消失、肛门排气与胃管撤离时间分别为(3.56±0.87)d vs(2.14±0.43)d、(5.79±1.02)d vs(3.58±0.84)d、(4.69±1.10)d vs(3.05±0.97)d、(6.43±1.78)d vs(4.09±1.12)d,差异有统计学意义(P<0.05);常规组与中药组不良反应总发生率分别为4.76%(2/42)、7.14%(3/42),差异无统计学意义(P>0.05)。治疗前,两组血清hsCRP、TNF-α、IL-8与PCT水平差异均无统计学意义(P>0.05);治疗后,中药组血清hsCRP、TNF-α、IL-8与PCT水平均低于常规组,分别为(30.43±8.76)vs(61.26±11.32)mg/L、(24.75±9.86)vs(43.07±12.14)ng/mL、(67.64±21.32)vs(98.77±28.96)pg/mL、(70.06±15.34)vs(125.63±19.48)pg/mL,差异有统计学意义(P<0.05)。结论:临床上将中药通腑承气汤用于术后早期炎症性肠梗阻患者,不仅可缩短患者胃肠功能康复所需的时间与减轻炎性反应,提高临床疗效,且不良反应未见明显增多,安全性尚可,有一定的临床使用及推广价值。  相似文献   
6.
<正>咳喘合剂是杭州市红十字会医院的临床经验方,由蜜麻黄、蜜款冬花、蜜紫菀、浙贝、黄芩、前胡、甘草等12味中药组成,具有宣肺平喘,止咳化痰的功效,临床用于小儿急慢性支气管炎、哮喘、过敏性咳嗽及上呼吸道感染、感冒后痒咳等症。为了规范咳喘合剂的提取工艺,确保制剂的疗效,根据处方中药物各组分的理化性质及药理特点,结合中医临床用药经验,采用正交实验法对咳喘合剂进行了提取工  相似文献   
7.
Diagnosis of motor neurone disease (MND) includes detection of small, involuntary muscle excitations, termed fasciculations. There is need to improve diagnosis and monitoring of MND through provision of objective markers of change. Fasciculations are visible in ultrasound image sequences. However, few approaches that objectively measure their occurrence have been proposed; their performance has been evaluated in only a few muscles; and their agreement with the clinical gold standard for fasciculation detection, intramuscular electromyography, has not been tested. We present a new application of adaptive foreground detection using a Gaussian mixture model (GMM), evaluating its accuracy across five skeletal muscles in healthy and MND-affected participants. The GMM provided good to excellent accuracy with the electromyography ground truth (80.17%–92.01%) and was robust to different ultrasound probe orientations. The GMM provides objective measurement of fasciculations in each of the body segments necessary for MND diagnosis and hence could provide a new, clinically relevant disease marker.  相似文献   
8.
A mixture model is described, which accommodates different Markov processes governing disease progression in a finite set of latent classes. We give special attention to the setting in which individuals are examined intermittently and transition times are consequently interval censored. A score test is developed to identify genetic markers associated with class membership. Simulation studies are conducted to validate the algorithm, assess the finite sample properties of the estimators, and assess the frequency properties of the score tests. A permutation test is recommended for settings when there is concern that the asymptotic approximation to the score test is poor. An application involving progression in joint damage in psoriatic arthritis (PsA) provides illustration and identifies human leukocyte antigen markers associated with unilateral and bilateral sacroiliac damage in individuals with PsA.  相似文献   
9.
This paper introduces a test of superiority of new anti-infective drug B over comparator drug A based on a randomized clinical trial. This test can be used to demonstrate assay (trial) sensitivity for noninferiority trials and rigorously tailor drug choice for individual patients. Our approach uses specialized baseline covariates XA,XB, which should predict the benefits of drug A and drug B, respectively. Using a response surface model for the treatment effect, we test for superiority at the (XA,XB) point that is most likely to show superiority. We identify this point based on estimates from a novel half-blind pseudo likelihood, where we augment a blinded likelihood (mixed over the treatment indicator) with likelihoods for the overall success rates for drug A and drug B (mixed over XA,XB). The augmentation results in much better estimates than those based on the mixed blinded likelihood alone but, interestingly, the estimates almost behave as if they were based on fully blinded data. We also develop an analogous univariate method using XA for settings where XB has little variation. Permutation methods are used for testing. If the “half-blind” test rejects, pointwise confidence interval can be used to identify patients who would benefit from drug B. We compare the new tests to other methods with an example and via simulations.  相似文献   
10.
Background: Maltreated children experience a variety of adverse outcomes including substance use problems. Although previous research indicated that there may be distinct trajectories of substance use among these youth, studies have examined them as if they were a single homogeneous group. Objectives: The goals of this study were to explore substance use trajectories among child welfare-involved youth and to identify characteristics that distinguish substance use trajectories. Methods: Data from the National Survey of Child and Adolescent Well-Being (NSCAW II) were used. Multilevel latent growth mixture modeling (MLGMM) was performed using a subsample of 625 youth from ages 11–17 years investigated for maltreatment in 2008–2009. Measures included self-reported use of substance use during the previous 30 days, demographic characteristics, maltreatment history, placement in out-of-home care, and behavioral health problems. Results: MLGMM identified two distinct substance use trajectory classes including High Stable Substance Use and Rapid Progression Use. Findings suggest that the experience of physical abuse is the key factor that distinguishes the two groups. When the effects of class-specific covariates were examined, results suggest that involvement in substance use behavior and its escalation vary between groups and are affected by youth’s different previous experiences. Conclusions/Importance: The results have important implications for understanding individual differences in substance use behavior over time and how these differences were shaped by youth’s experiences of family adversity. Study findings may be helpful for developing and enhancing the effectiveness of interventions targeted at decreasing substance use behaviors in child welfare-involved youth.  相似文献   
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