基于增强图卷积神经网络的病毒形态识别方法研究

背景 透射电子显微镜（TEM）是检测病毒的重要手段,传统TEM检测常依靠专家手工观察,操作步骤繁琐,且已有机器学习方法易受到背景、噪声的影响,导致病毒检测方法准确率差、效率低且耗时长。 目的 探讨增强图卷积神经网络（EGCN）对TEM图像中的病毒形态自动识别问题,以提高TEM病毒检测的效率。 方法 EGCN模型利用卷积神经网络（CNN）提取像素间的局部特征信息,并结合样本特征之间的最近邻关系利用图卷积网络（GCN）进行图特征学习。在模型优化中联合优化群体超分类损失和分类交叉熵损失以提高EGCN模型对病毒类别信息特征的提取能力,较CNN对TEM病毒图像特征具备更强的特征提取能力。 结果 通过不同方法在15类TEM病毒图像数据集上开展实验,EGCN达到3.40%的top-1错误率、1.88%的top-2错误率、96.65%的精确度和96.60%的召回率,并通过一系列对比实验表明EGCN模型可以有效避免TEM图像中背景、噪声等的影响,提高对病毒识别的准确率。 结论 EGCN可以有效解决病毒形态识别任务,为病毒的诊断提供重要的参考价值。     

Glycation of extracellular matrix proteins impairs migration of immune cells

The immune response during aging and diabetes is disturbed and may be due to the altered migration of immune cells in an aged tissue. Our study should prove the hypothesis that age and diabetes‐related advanced glycation end products (AGEs) have an impact on the migration and adhesion of human T‐cells. To achieve our purpose, we used in vitro AGE‐modified proteins (soluble albumin and fibronectin [FN]), as well as human collagen obtained from bypass graft. A Boyden chamber was used to study cell migration. Migrated Jurkat T‐cells were analyzed by flow cytometry and cell adhesion by crystal violet staining. Actin polymerization was determined by phalloidin‐Alexa‐fluor 488‐labeled antibody and fluorescence microscopy. We found that significantly fewer cells (50%, p = 0.003) migrated through methylglyoxal modified FN. The attachment to FN in the presence of AGE‐bovine serum albumin (BSA) was also reduced (p < 0.05). In ex vivo experiments, isolated collagen from human vein graft material negatively affected the migration of the cells depending on the grade of AGE modification of the collagen. Collagen with a low AGE level reduced the cell migration by 30%, and collagen with a high AGE level by 60%. Interaction of the cells with an AGE‐modified matrix, but not with soluble AGEs like BSA‐AGE per se, was responsible for a disturbed migration. The reduced migration was accompanied by an impaired actin polymerization. We conclude that AGEs‐modified matrix protein inhibits cell migration and adhesion of Jurkat T‐cells.     

我院2年间骨科髋关节置换术预防性应用抗菌药物的临床评价

目的:评价我院骨科髋关节置换术预防性应用抗菌药物整治活动的效果,以期逐步扩大抗菌药物专项整治成效,建立长效管理机制。方法:随机抽取我院骨科行髋关节置换术患者182例,其中2010年4月-2011年4月(整治活动前组)90例,2011年11月-2012年11月(整治活动后组)92例。对患者的自然情况、抗菌药物使用品种、使用时机、使用疗程等进行汇总及评价,并将结果应用SPSS 18.0软件进行统计分析,比较两组患者预防性应用抗菌药物的合理性。结果:开展抗菌药物专项整治后,抗菌药物预防性应用主要药物由第3代头孢菌素(31.11%)变为第1代头孢菌素(54.35%),其他各类药物的使用率均有显著下降(P<0.01);预防用药时机由大于术前2 h(58.89%)变为切皮前0.5² h(88.04%);用药疗程由平均(11.91±3.87)d变为(4.07±2.32)d;抗菌药物平均总费用下降71.06%。经过整治活动后药物选择不合理、术前用药不合理、更换药物不合理以及联合用药不合理的情况均有显著下降(P<0.01)。结论:抗菌药物专项整治活动后,我院骨科髋关节置换术预防性应用抗菌药物合理性得到明显改善,抗菌药物合理应用的长效管理机制已逐步建立。     

The IST registry

Intracoronary brachytherapy has been established in Europe and the US as an evidence-based treatment of in-stent restenoses. The objective of the IST Registry is to register all patients treated in Germany with intracoronary radiation and to observe the clinical outcome for a duration of 5 years. The required set of data for each patient is kept to a minimum to encourage participation. All data are entered online. In the internet, each participating site can, at any time, check their most important parameters and compare them with those of other sites. Presently, the Novoste System is used in 58 catheter labs and the Guidant System in 16, while several sites use both. The requirements regarding radiation safety in intracoronary application of gamma radiation are very strict in Germany, so the Cordis-Gamma System is used in only one German lab. In a first analysis of 332 radiated stenoses, it was observed that late vessel occlusion could occur even after 6-month administration of clopidogrel (in addition to ASA)--without new stents being implanted within the brachytherapy session. Clopidogrel should thus be administered in addition to aspirin for at least a year. Ca. 270 patients per month receive intracoronary radiation in Germany, so the IST Registry will provide important data regarding long-term observation and a foundation for future negotiations with insurance companies potentially bearing the costs. At present, neither the physician's service nor the material costs are reimbursed. The IST Registry can furthermore be used as a comparative database regarding long-term outcome following implantation of antiproliferative-coated stents.     

Rapid prenatal diagnosis of beta thalassemia using DNA amplification and nonradioactive probes

We used in vitro DNA amplification by the polymerase chain reaction and nonradioactive probes for prenatal diagnosis of beta thalassemia in Chinese from the Guangdong province. Exact molecular diagnoses were made in all 20 fetuses studied over a 6-month period. We conclude that this method of prenatal diagnosis for beta thalassemia is a viable approach in many parts of the world where this disease is common.     

On social polarization and ordinal variables: the case of self-assessed health

Social polarization refers to the measurement of the distance between different social groups, defined on the basis of variables such as race, religion, or ethnicity. We propose two approaches to measuring social polarization in the case where the distance between groups is based on an ordinal variable, such as self-assessed health status. The first one, the ‘stratification approach’, amounts to assessing the degree of non-overlapping of the distributions of the ordinal variable between the different population subgroups that are distinguished. The second one, the ‘antipodal approach’, considers that the social polarization of an ordinal variable will be maximal if the individuals belonging to a given population subgroup are in the same health category, this category corresponding either to the lowest or to the highest health status. An empirical illustration is provided using the 2009 cross-sectional data of the European Union Statistics on Income and Living Conditions (EU-SILC). We find that Estonia, Latvia, and Ireland have the highest degree of social polarization when the ordinal variable under scrutiny refers to self-assessed health status and the (unordered) population subgroups to the citizenship of the respondent whereas Luxembourg is the country with the lowest degree of social polarization in health.     

鞍山市铁东区公共场所使用化妆品存在的主要卫生问题及对策

目的了解鞍山市铁东区公共场所使用化妆品卫生问题,保障使用者身体健康。方法对2013年度鞍山市铁东区卫生防疫站辖区内监管的公共场所随机抽检化妆品,对公共场所使用化妆品单位数及比例,化妆品标签标识卫生问题等进行描述。结果住宿业化妆品使用情况为56%,其他三种场所100%使用。化妆品标签标识检查住宿业合格率最低,仅为50%。国产特殊用途化妆品持有效证件率仅为65%,普通的仅为62%。标签标识问题突出,进货渠道复杂。化妆品抽检合格率低。结论公共场所的化妆品卫生质量令人担忧。     

鞍山市铁东区公共场所卫生基层问题及解决建议

笔者作为基层卫生监督工作人员经过十多年的公共场所卫生监督工作,通过对鞍山市铁东区公共场所卫生监督情况进行分析。发现当前存在许多公共场所卫生监督执法困难和难题,主要表现为卫生监督队伍薄弱,新兴公共场所剧增,公共场所执法依据不确定性（无法可依）等问题。笔者提出相应的解决建议,应转变卫生监督观念,提高监督管理质量。     

肝细胞生长因子对人脐带间充质干细胞增殖、黏附及迁移影响的体外研究

目的：探讨肝细胞生长因子( HGF)对人脐带间充质干细胞( hUCMSCs)增殖、黏附及迁移能力的影响。方法按照不同腺病毒感染 hUCMSCs 分为实验组( Ad-GFP-HGF )和对照组( Ad-GFP )。以最佳感染复数转染hUCMSCs,观察细胞形态变化以及GFP蛋白的表达。比较各组细胞增殖能力、黏附能力及迁移能力。 Western Bolt检测各组细胞HGF的表达水平。结果对照组和实验组均出现了GFP的表达,实验组hUCMSCs的增殖、黏附及迁移能力均较对照组增强(P<0．05)。实验组细胞HGF的表达水平显著高于对照组(P<0．05)。结论 HGF的高表达能明显促进hUCMSCs的增殖、黏附和迁移。