山莴苣苦素改善FFA诱导的HepG2细胞脂肪变性及氧化应激的研究

目的:研究山莴苣苦素对游离脂肪酸(FFA)诱导的HepG2细胞脂肪变性的改善作用,并初步探讨其可能作用机制.方法:观察山莴苣苦素对HepG2细胞活力的影响.采用FFA诱导培养HepG2细胞,构建脂肪变性模型(NAFLD体外模型),并用山莴苣苦素干预72h后,检测各组细胞内脂滴数量、甘油三酯(TG)和总胆固醇(TC)含量...     

脾动脉阻断联合射频消融术治疗脾功能亢进的疗效观察

【摘要】 目的 总结脾动脉球囊阻断联合脾脏射频消融术（RFA）治疗肝硬化门静脉高压型脾功能亢进的有效性及经验。方法 在脾动脉球囊阻断状态下对15例脾功能亢进患者行经皮穿刺脾脏RFA,RFA平均时间为（46．4±5．4）min。术后3 d、1周、1个月、3个月和6个月监测血常规,术后1个月复查腹部CTA。结果 1例患者术后出现左侧大量血性胸腔积液,给予止血及胸腔积液引流后好转,其余患者未发生严重并发症。RFA后1个月行腹部CTA检查示RFA毁损范围占脾脏总体积的比率为34．3％～71.8％,平均（56.20±13.09）％。术前血细胞计数示:白细胞为（3.88±1.75）×109/L,红细胞（4.06± 0.37）×1012/L,血小板（48.14±11.33）×109/L。RFA术后1个月复查示:白细胞（5.62±1.61）×109/L,血小板（132.29±33.20）×109/L;与术前相比,血小板和白细胞显著升高（P<0．05）。结论 脾动脉球囊阻断联合RFA治疗肝硬化门静脉高压型脾功能亢进具有较高的安全性,且近期疗效可靠。     

基于平台的煤矿液压支架管理系统设计

为了加大煤矿的生产产量,企业使用的机械设备越来越多,在这些设备中液压支架的使用受到越来越多的重视,它能够改善和提升煤矿生产和运输设备的效率,同时也减轻了工作人员的劳动强度。文章介绍了煤矿液压支架控制器的控制原理,探讨了基于平台的液压支架管理系统的设计。     

Line and point cluster models for spatial health data

Spatial cluster modelling of small area disease incidence and mortality has previously focused on clusters where excess risk is distributed around fixed points, and the aim is the reconstruction of these points (cluster centers). Often there is a need to assess clusters of a different form, such as around roads or river systems. These clusters are often linear or can be approximated by combinations of several linear segments. In this paper the recovery of point and line clusters is considered jointly. An example application is given where both linear or point clustering could be present.     

7-取代喹唑啉酮共振异构化的量子化学计算

采用量子化学中的密度泛函理论方法(DFT),在B3LYP/6-31G*水平和标准状况(298.15K,101.325kPa)下分别计算了7-取代喹唑啉酮和其异构体的热化学参数(Hθ,Gθ).频率计算表明,优化的结构均为稳定的构型;热化学方程计算结果说明,通常情况下该类化合物均以7-取代喹唑啉酮的形式存在.     

哈萨克文信息处理现状中的若干问题探讨

通过信息领域术语的规范化及翻译、文字输入法原则和键盘布局、语料库建设与语料管理、机器翻译以及文字转换等方面的信息化建设的现状和进展为例,就目前开发和研究哈萨克文信息处理中存在的若干问题进行探讨。     

Layer-by-layer films of chitosan,poly(vinyl sulfonic acid), and platinum for methanol electrooxidation and oxygen electroreduction

We describe an approach for manipulation of biodegradable chitosan and poly(vinyl sulfonic acid) (PVS) in layer-by-layer (LBL) film adsorbed onto gold via ionic attraction. H₂PtCl₆ was deposited onto the LBL film, with chitosan/PVS layers serving as templates to yield metallic platinum. In electrochemical experiments this LBL film exhibited electrochemical stability, low permeability to methanol and conduction/diffusion of proton to maintain the electrolytic connection. The Pt/chitosan/PVS electrode also displayed electroreduction of molecular oxygen. With these features, this Pt/chitosan/PVS film may be used between the catalyst layer and the proton exchange membrane (PEM) in direct methanol fuel cells (DMFC) and biofuel cells.     

Theoretical study of structural,electronic and thermal properties of Zn1−xBexS ternary alloy

The structural, the electronic and the thermal properties of Zn_1?xBe_xS ternary alloy have been calculated using the full-potential linearized-augmented plane wave (FP-LAPW) method. The exchange and correlation potential is treated by the generalized-gradient approximation (GGA) using the Perdew–Burke–Ernzerhof (PBE) parameterization. Moreover, the Engel–Vosko GGA formalism is also applied to optimize the corresponding potential for band structure calculations. The ground state properties such as lattice constants and bulk modulus are in good agreement with numerous experimental and theoretical data. The thermodynamic stability of this alloy was explained by calculating the phase diagram. The quasi harmonic Debye model, using a set of total energy versus volume calculations obtained with FP-LAPW method is applied to study the thermal and vibrational affects. Temperature effect on the lattice parameter, thermal expansion coefficient, heat capacity and Debye temperature is determined from the non-equilibrium Gibbs function.     

Microscopic investigations and pharmacognostic techniques for the standardization of the fruits of Rosa laxa Retz

Rosa laxa Retz., a shrub belonging to the family Rosaceae, is widely distributed in the northern foothills of the Tianshan Mountains in Xinjiang, China. The fruits of R. laxa (FRL) has antibacterial, hypolipidemic, and antioxidant effects. In this study, FRL was subjected to pharmacognostic identification of its source, morphology, microscopic characteristics, and physicochemical properties. The microscope showed that the cross-sectional features of FRL were obvious, and the FRL powder contained vessel, parenchyma cells, exocarp cells, pollen grains, and cluster crystals. Scanning electron microscopy (SEM) analysis results show that numerous villi and many small particles (particle size of 5–50 μm) were observed in the FRL powder, and there are many gullies on the surface of the particles. In addition, the secondary metabolites of FRL were characterized via ultraviolet–visible (UV–Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and thin-layer chromatography (TLC). Results showed that FRL contains various secondary metabolites, including flavonoids, phenolic acids, glycosides, and tannins. Water as the extraction solvent had the highest extraction rate and the contented of total flavonoids was 2.88 mg/g, and the contented of total polyphenols was 54.89 mg/g. Moreover, TLC identification revealed that it contains catechin and tiliroside. These parameters of FRL, which are reported herein, are important to the development of the pharmacognostic standards, as well as in the identification and quality control of FRL.