脂质比值与代谢综合征的关联及预测价值评价：基于多阶段横断面研究

背景 随着代谢性疾病发病率的上升,代谢综合征(MS)的预防与控制引起广泛的关注。而脂质比值是重要的筛查指标之一,与MS之间的关系成为热点研究话题。目的 基于贵州省多阶段横断面研究人群分析三酰甘油/高密度脂蛋白胆固醇(TG/HDL-C)、总胆固醇/HDL-C(TC/HDL-C)、低密度脂蛋白胆固醇/HDL-C(LDL-C/HDL-C)及非高密度脂蛋白胆固醇(non-HDL-C)与MS发病风险的关联及预测价值评价。方法 回顾性选取贵州省参与2010年全国疾病监测地区慢性病及危险因素调查、2013年中国慢性病及其危险因素监测、2015年中国成人慢性病与营养监测和2018年中国成人慢性病与营养监测的21 727例自然人群为研究对象,收集研究对象的基线资料,根据是否患有MS将研究对象分为MS组(n=4 981)和非MS组(n=16 746)。绘制受试者工作特征曲线(ROC曲线)分别评价男性和女性TG/HDL-C、TC/HDL-C、LDL-C/HDL-C和non-HDL-C对MS的预测价值。通过Delong检验比较脂质比值预测MS发生的ROC曲线下面积(AUC)的差异。采用多因素Logistic回...     

煤直接液化浆态反应器内气-浆流动与反应的CFD模拟

以褐煤直接液化小试反应器为研究对象,将反应器内气-液-固三相流动简化为气-浆两相流动,使用Fluent 14.0及双流体模型,模拟预测高温、高压条件下气-浆两相流动及反应的耦合过程。对反应器内等温流场进行了三维瞬态模拟,结果表明：反应器内总体气含率较低,约为0.016 5;气-浆流速较低,且壁面附近浆液回流和返混显著;浆液在反应器内平均停留时间约为70 min,与液化反应所需时间匹配。使用Matlab最小二乘曲线拟合方法,获得褐煤在430℃、10 MPa下的液化反应速率常数,通过用户自定义函数（UDF）将动力学参数导入Fluent求解器,对反应器内流动和反应过程耦合求解。结果显示：反应器出口处煤的转化率约为89.25%,沥青质（PAA）和油气（OG）产率分别为26.33%和61.81%,与测量值吻合。此数学模型及数值方法有望应用于中试及工业装置,指导液化工艺优化和反应器的设计放大。     

骆驼蓬生物碱乳膏剂的质量标准研究

摘 要 目的： 初步建立骆驼蓬生物碱乳膏剂的质量控制方法。方法: 按照《中国药典》2010年版一部附录有关制剂通则要求,对制剂进行一般质量检查。以去氢骆驼蓬碱和骆驼蓬碱为指标,采用薄层色谱法对乳膏剂进行薄层色谱鉴别。以去氢骆驼蓬碱、骆驼蓬碱、鸭嘴花碱为指标,采用高效液相色谱法对制剂进行含量测定。结果: 检查项目均符合《中国药典》要求。薄层色谱中供试品在与对照品相同位置上显相同颜色斑点。去氢骆驼蓬碱、骆驼蓬碱和鸭嘴花碱分别在3.440～110.000 μg·ml^-1、3.340～107.000 μg·ml^-1和1.380～22.000 μg·ml^-1浓度范围内线性关系良好,平均回收率分别为98.1% (RSD=1.75%, n=6)、99.8% (RSD=1.78%,n=6)和99.3% (RSD=1.95%,n=6)。结论:所建立的质量控制方法符合方法学要求,为最终制定骆驼蓬生物碱乳膏剂质量标准奠定了试验基础。     

The clinical pattern differentiates ANCA-positive infective endocarditis patients from ANCA-associated vasculitis patients: a 23 years’ retrospective cohort study in China and follow-ups

Clinical Rheumatology - Patients with infective endocarditis (IE) may present rheumatic manifestations concurrent with various autoantibodies and thus mimic antineutrophil cytoplasmic antibody...     

Interaction of oxalic acid with methylamine and its atmospheric implications

Oxalic acid, which is one of the most common dicarboxylic acids, is expected to be an important component of atmospheric aerosols. However, the contribution of oxalic acid to the generation of new particles is still poorly understood. In this study, the structural characteristics and thermodynamics of (C₂H₂O₄)(CH₃NH₂)_n (n = 1–4) were investigated at the PW91PW91/6-311++G(3df,3pd) level of theory. We found that clusters formed by oxalic acid and methylamine are relatively stable, and the more the atoms participating in the formation of a ring-like structure, the more stable is the cluster. In addition, via the analysis of atmospheric relevance, it can be revealed that clusters of (C₂H₂O₄)(CH₃NH₂)_n (n = 1–4) have a noteworthy concentration in the atmosphere, which indicates that these clusters could be participating in new particle formation. Moreover, by comparison with (H₂C₂O₄)(NH₃)_n (n = 1–6) species, it can be seen that oxalic acid is more readily bound to methylamine than to ammonia, which promotes nucleation or new particle formation. Finally, the Rayleigh scattering properties of clusters of (C₂H₂O₄)(CH₃NH₂)_n (n = 1–4) were investigated for the first time to determine their atmospheric implications.

Oxalic acid, which is one of the most common dicarboxylic acids, is expected to be an important component of atmospheric aerosols.