基于多层次集成学习的骨质疏松辅助诊断研究

目的 原发性骨质疏松是一种起病隐匿、病程较长,在中老年人中高发的疾病,其可引起包括骨折在内的一系列严重症状,是我国中老年人致残致死的主要原因之一。与骨质疏松相关的生理检验指标有很多,如何筛选利用这些指标为诊断服务、建立诊断模型,尚未有成熟、统一的方法。方法 利用人工智能相关技术,对临床骨质疏松患者指标使用多种特征相关性算法进行特征选择,并在此基础上提出了一种多层次的集成学习框架：SAB-SVMKNN算法,其通过将内部同质学习器集成和外部异质学习器集成结合,将集成学习中的Boosting算法和Bagging算法使用Stacking进行集成,构建性能更强,适应性更好地诊断预测模型。结果 使用特征选择从原始数据中的31项临床指标中筛选了对于骨质疏松最重要的8种相关特征,通过这种方式使各模型准确率平均提高了9.2%,且该研究对应的模型准确率提升18.6%,最终达到了94.8%的准确率。结论 特征选择对于临床诊断和骨质疏松疾病的研究具有重要意义,该研究构建的预测模型可以有助于提高医生的诊断准确率。     

Estimation of exposure to toxic releases using spatial interaction modeling

Background  

The United States Environmental Protection Agency's Toxic Release Inventory (TRI) data are frequently used to estimate a community's exposure to pollution. However, this estimation process often uses underdeveloped geographic theory. Spatial interaction modeling provides a more realistic approach to this estimation process. This paper uses four sets of data: lung cancer age-adjusted mortality rates from the years 1990 through 2006 inclusive from the National Cancer Institute's Surveillance Epidemiology and End Results (SEER) database, TRI releases of carcinogens from 1987 to 1996, covariates associated with lung cancer, and the EPA's Risk-Screening Environmental Indicators (RSEI) model.     

Molecular characterization of CTX‐M‐15‐producing clinical isolates of Escherichia coli reveals the spread of multidrug‐resistant ST131 (O25:H4) and ST964 (O102:H6) strains in Norway

Nationwide, CTX‐M‐producing clinical Escherichia coli isolates from the Norwegian ESBL study in 2003 (n=45) were characterized on strain and plasmid levels. Bla_CTX‐M allele typing, characterization of the genetic environment, phylogenetic groups, pulsed field gel electrophoresis (PFGE), serotyping and multilocus sequence typing were performed. Plasmid analysis included S1‐nuclease‐PFGE, polymerase chain reaction‐based replicon typing, plasmid transfer and multidrug resistance profiling. Bla_CTX‐M‐15 (n=23; 51%) and bla_CTX‐M‐14 (n=11; 24%) were the major alleles of which 18 (78%) and 6 (55%), respectively, were linked to ISEcp1. Thirty‐two isolates were of phylogenetic groups B2 and D. Isolates were of 29 different XbaI‐PFGE‐types including six regional clusters. Twenty‐three different O:H serotypes were found, dominated by O25:H4 (n=9, 20%) and O102:H6 (n=9, 20%). Nineteen different STs were identified, where ST131 (n=9, 20%) and ST964 (n=7, 16%) were dominant. Bla_CTX‐M was found on ≥100 kb plasmids (39/45) of 10 different replicons dominated by IncFII (n=39, 87%), FIB (n=20, 44%) and FIA (n=19, 42%). Thirty‐nine isolates (87%) displayed co‐resistance to other classes of antibiotics. A transferable CTX‐M phenotype was observed in 9/14 isolates. This study reveals that the majority of CTX‐M‐15‐expressing strains in Norway are part of the global spread of multidrug‐resistant ST131 and ST‐complex 405, associated with ISEcp1 on transferrable IncFII plasmids.     

ATP生物荧光肿瘤体外药物敏感性检测在口腔癌化疗中的应用

目的探讨肿瘤体外药敏实验ATP生物荧光法(ATP-TCA)在口腔癌化疗中的应用。方法应用ATP生物荧光肿瘤体外药物敏感性检测法,检测48例口腔癌组织对6种常用化疗方案的敏感性。结果组织标本的可评估率为92.0%。口腔癌对TAT DDP最敏感,体外有效率为83.3%,其次为5-Fu DDP(75.0%),BLM(54.2%),DDP(60.4%),MTX(45.8%),5-Fu(62.5%)。化疗药物对口腔癌的杀伤作用具有较强的个体差异性。结论TP生物荧光肿瘤体外药物敏感性检测法敏感性高、稳定性好、简便、快速、检测结果可靠,可用于临床制定个体化的化疗方案。     

原发性肝细胞癌患者外周血单个核细胞中HBV-DNA含量检测的意义

目的:了解原发性肝细胞癌(PHCC)患者外周血单个核细胞(PBMC)中乙型肝炎病毒核酸(HBV-DNA)的整合情况,以揭示其在HCC发病机制中的作用。方法:应用荧光定量聚合酶链反应(FQ-PCR)技术检测32例HCC患者和45例慢性乙型肝炎(CHB)患者血清和PBMC中HBV-DNA含量,引物和探针设计选择HBVC区的DNA序列。结果:HCC组和CHB组患者血清中HBV-DNA阳性率分别为62.5%(20/32)和46.7%(21/45)、HBV-DNA均值(不含阴性)分别为105.50±1.52和105.05±1.45copies/ml,PBMC中HBV-DNA阳性率分别为87.5%(28/32)和51.1%(23/45)(P<0.01)、HBV-DNA均值(不含阴性)分别为104.51±1.32和104.05±1.05copies/ml;HCC组血清和PBMC中HBV-DNA阳性率相比较有统计学差异(62.5%比87.5%,P<0.05);HCC组和CHB组血清和PBMC中HBV-DNA同时阳性时,其HBV-DNA含量均呈正相关(P<0.01)。结论:HCC患者PBMC中存在HBV-DNA整合的现象;作为临床预测HCC发生的风险指标,PBMC中HBV-DNA含量的检测与穿刺肝组织相比具有轻创或无创的优点。     

DC-SIGNR基因多态性与丙型肝炎病毒载量的相关性研究

目的了鹪丙型肝炎患者DC-SIGN／DC-SIGNR基因颈区重复序列的遗传多态性分布，探讨DC-SIGNR基因多态性与丙型肝炎病毒（HCV）载量的关系。方法采用PCR结合DNA测序对300例丙型肝炎患者DC—SIGNR重复序列多态性进行基因分型和测序分析；同时检测了患者的HCV病毒载量。结果该研究发现携带7等位基因（中等的）的患者、其HCV病毒载量水平低于携带9等位基因（较长的）的患者（P〈0.05），此外7／7基因型的患者组其HCV病毒载量水平低于9／7基因型的患者组，两组的差异有统计学意义（P〈0．05）、提示HCV病毒更易与携带较长DC—SINGR等位基因的患者结合。结论DC-SIGNR遗传多态性可能与HCV病毒在个体内的复制有关。     

宫腹腔镜联合应用诊治输卵管性不孕的临床研究

目的:探讨宫腔镜、腹腔镜联合诊治输卵管阻塞性不孕的效果。方法:对诊断为不孕症的病人,首先进行输卵管通液术,对于通液结果为输卵管不通者,应用76%的泛影葡胺行子宫、输卵管造影。对诊断为双侧输卵管阻塞者则宫腔镜与腹腔镜联合应用,宫腔镜下观察宫腔内、输卵管、子宫口是否存在病变,做选择性输卵管插管通液术,腹腔镜直视下观察输卵管阻塞度及阻塞部位,并做相应手术。结果:双侧通畅15例,一侧通对侧阻塞9例,一侧通而不畅对侧通畅6例,双侧阻塞2例。均较单用宫腔插管通液效果好。结论:宫、腹腔镜联合能充分利用二者的优点,相互补充,明确输卵管阻塞的部位和程度,对输卵管复通有一定临床价值。     

5''-磷酸胞苷体外抗氧化作用的研究

近年来的研究表明,5'-核苷酸具有提高免疫力、促生长、抗氧化、促进机体损伤修复、减少细胞凋亡、减轻炎性反应等功能[1-4].但关于5'-核苷酸的抗氧化作用机制尚无系统研究.本研究分析体外条件下5'-磷酸胞苷(5'-CMP)的清除活性氧能力及其对氧化损伤小鼠脾细胞的修复作用,旨在阐明其可能的作用机制.