Allergic reactions to raw, pasteurized, and homogenized/pasteurized cow milk: a comparison

Five children aged 12-40 months with IgE-mediated adverse reactions to cow milk (immediate onset clinical pattern of cow milk allergy) were orally challenged double-blind in random order with three different milk preparations processed from the same batch of milk 1) raw untreated cow milk, 2) pasteurized cow milk, 3) homogenized and pasteurized cow milk, and 4) Nutramigen (a commercial hypoallergenic infant formula based on hydrolysed casein) as placebo. Skin prick tests with the same preparations were also performed. On oral challenge the three different processed milk types provoked significant and similar allergic reactions in each child, and no adverse reactions followed the challenge with placebo (Nutramigen). Skin prick test with the same milk products were positive in all children and comparable to the results with an extract of purified raw cow milk protein (Soluprick), whereas Nutramigen did not elicit any skin reactions. A tendency towards a lower threshold of reaction and larger skin reactions induced by the processed milk preparations might indicate an increased ability of pasteurized and homogenized/pasteurized milk to evoke allergic reactions in patients allergic to milk.     

基于“药辅合一”理念的Pickering乳技术提升儿科用药羚珠散中石菖蒲挥发油热稳定性的研究

目的 在“药辅合一”理念下导入Pickering乳技术,提升儿科用药羚珠散中石菖蒲挥发油的稳定性。方法 对羚珠散各饮片粉末进行初步表征,确定稳定剂。通过成乳量、包油量和乳剂形态筛选出最佳稳定剂质量浓度、油水比和制备方法。并使用近红外光谱（nearinfraredspectroscopy,NIRS）分析石菖蒲油在Pickering乳中的包裹状态。比较不同时间下各组别挥发油的保有量、丙二醛和过氧化物的含量。再通过GC-MS分析其中成分的变化趋势。结果 筛选出珍珠粉作为Pickering乳的稳定剂,珍珠粉质量浓度为65 mg/mL,油水比9∶11为最优成乳条件,高压均质法为最优的制备方法,NIRS分析可知石菖蒲挥发油被珍珠粉包裹,Pickering乳液中没有形成新的化学键。对比各组在不同时间段下石菖蒲油的保有率和其中丙二醛和过氧化物含量,可知40℃放置1、3、8 h的Pickering乳剂相比于石菖蒲挥发油组有更高的保有率和更低的氧化程度。GC-MS分析结果表明,相比于石菖蒲挥发油组,Pickering乳组挥发性成分的稳定性显著提高。结论 在“药辅合一”理念下Pickering乳可用于含油固...     

以茶皂素为天然乳化剂制备水飞蓟素纳米乳及其理化性质考察

目的 以茶皂素为天然乳化剂制备水飞蓟素纳米乳（silymarin nanoemulsion,SM-NE）。方法 使用高速剪切联合高压均质法制备SM-NE,以平均粒径、粒度多分散系数（polydispersity index,PDI）、分层指数和外观为主要评价指标,采用单因素试验对处方和制备工艺进行优化;以摩尔增溶比（molar solubilization ratio,MSR）和胶束-水分配系数（K_m）作为评价指标探究了茶皂素对水飞蓟素的增溶能力;对最佳处方和工艺制备的SM-NE进行了理化性质和稳定性考察。结果 SM-NE的最佳处方为水飞蓟素用量0.15%,茶皂素用量为0.3%,油相用量为5%,最佳制备工艺为剪切速率16 000 r/min,剪切时间3 min,均质压力为100 MPa,均质次数为8次;茶皂素对水飞蓟素增溶参数值MSR和K_m分别为0.011 1和2.31;制得的SM-NE的平均粒径为（204.1±2.8）nm,PDI为0.058±0.007,电导率为（117.8±0.9）μs/cm,pH值为7.31±0.10,浊度为（59.75±1.10）cm^-1,水飞蓟素溶解度为（1.22±0.05）mg/mL;稳定性结果显示,SM-NE具有良好的离心稳定性和储存稳定性。结论 以茶皂素为天然乳化剂成功制备了稳定的SM-NE,茶皂素是一种潜在的用于水飞蓟素新型绿色纳米制剂生产的天然增溶剂。     

Stochastic Multiscale Heat Transfer Analysis of Heterogeneous Materials with Multiple Random Configurations

This study presents a new stochastic multiscale analysis approach to analyze the heat transfer performance of heterogeneous materials with random structures at different length scales. The heterogeneities of the materials are taken into account by periodic layouts of unit cells, consisting of randomly distributed inclusion dispersions and homogeneous matrix on the microscale and mesoscale. Based on the reiterated homogenization, a novel unified micro-meso-macro stochastic multiscale formulation is established and the scale gap is correlated by means of two-scale asymptotic expansions. Also, the stochastic multiscale formulae for computing the effective thermal property and temperature field are derived successively. Then, the stochastic prediction algorithm coupled with the finite element method is brought forward in details. The accuracy of the implemented stochastic multiscale analysis is verified by comparing the results against the experimental data for three scales heterogeneous materials with several different material combinations. The comparison demonstrates the usability of the proposed stochastic multiscale method for the determination of the thermal behaviors. This study offers a unified multiscale framework that enables heat transfer behavior analysis of heterogeneous materials with multiple random configurations.     

Influence of Boundary Conditions on Numerical Homogenization of High Performance Concrete

Concrete is the most widely used construction material nowadays. We are concerned with the computational modelling and laboratory testing of high-performance concrete (HPC). The idea of HPC is to enhance the functionality and sustainability of normal concrete, especially by its greater ductility as well as higher compressive, tensile, and flexural strengths. In this paper, the influence of three types (linear displacement, uniform traction, and periodic) of boundary conditions used in numerical homogenization on the calculated values of HPC properties is determined and compared with experimental data. We take into account the softening behavior of HPC due to the development of damage (micro-cracks), which finally leads to failure. The results of numerical simulations of the HPC samples were obtained by using the Abaqus package that we supplemented with our in-house finite element method (FEM) computer programs written in Python and the homogenization toolbox Homtools. This has allowed us to better account for the nonlinear response of concrete. In studying the microstructure of HPC, we considered a two-dimensional representative volume element using the finite element method. Because of the random character of the arrangement of concrete’s components, we utilized a stochastic method to generate the representative volume element (RVE) structure. Different constitutive models were used for the components of HPC: quartz sand—linear elastic, steel fibers—ideal elastic-plastic, and cement matrix—concrete damage plasticity. The numerical results obtained are compared with our own experimental data and those from the literature, and a good agreement can be observed.     

利用微透析技术进行青藤碱贴剂的生物等效性研究

目的：研究不同制剂工艺的青藤碱凝胶贴剂的生物等效性，探讨微透析技术在生物等效性研究中的可行性和优越性。方法：以不同工艺制备青藤碱的普通凝胶贴剂和脂质体凝胶贴剂，以裸鼠为实验动物进行经皮给药后，分别采用组织匀浆法及微透析法对青藤碱的体内药量的进行测定。结果：组织匀浆法的测定结果显示出经过20h以上的时间后，脂质体凝胶贴剂比普通凝胶贴剂具有更高的皮肤局部剩余药量；而微透析法的检测结果则显示出在整个测定过程中，脂质体凝胶贴剂比普通凝胶贴剂具有更高的皮肤局部瞬间药量，且皮肤局部药时曲线与国际上报道的大多数经皮吸收情况相符。结论：青藤碱的脂质体凝胶贴剂比普通凝胶贴剂具有更高的局部生物利用度，且脂质体可能存在贮库效应；微透析技术可用于制剂的生物利用度及生物等效性研究。     

2种方法制备银杏内酯长循环固体脂质纳米粒的比较

目的:研究银杏内酯AB长循环固体脂质纳米粒(GAB-LSLN)的制备方法,并探讨GAB-LSLN的主要理化性质。方法:分别采用超声法和高压乳匀法制备GAB-LSLN。在电镜下观察其形态,测定其粒径、Zeta电位和包封率,并在室温下放置4周,观察GAB-LSLN的稳定性。结果:超声法制备的GAB-LSLN在透射电镜下呈片状存在,形态不规则;高压乳匀法制备的GAB-LSLN呈球状,形态规则。超声法和高压乳匀法制备的GAB-LSLN粒径分别为(219.6±14.3)nm和(173.9±10.4)nm(P<0.001);Zeta电位分别为(—21.12±1.03)mv和(—27.43±2.14)mV(P<0.001),包封率分别为(85.05±0.67)%和(92.49±0.88)%(P<0.001)。高压乳匀法制备的GAB-LSLN室温放置4周后,粒径无显著增加(P>0.05)。结论:高压乳匀法制备GAB-LSLN具有粒径小、稳定性和包封率高的特点,优于超声法。     

齐墩果酸纳米悬浮液的制备

 目的探讨运用高压匀质技术制备齐墩果酸纳米悬浮液的可行性。方法以纳米粒粒径及多分散指数为指标,研究各影响因素如压力、循环次数、表面活性剂种类及用量对纳米悬浮液的影响。并研究纳米化齐墩果酸的溶解度及体外溶出行为。结果匀质压力是决定纳米粒粒径的最主要因素,增加循环次数可以使纳米粒的单分散性增加,表面活性剂对维持体系稳定性起着不可忽视的作用。纳米化齐墩果酸的溶解度及药物溶出速率得到明显提高。结论高压匀质技术可以成功用于制备齐墩果酸纳米悬浮液。     

《住院医师规范化培训基地认定标准》和《住院医师规范化培训内容与标准》修订的解读

住院医师规范化培训(住培)是医学生成长为合格医生的必由之路。自2014年国家全面推行住培,儿科住培工作总体进展顺利,取得有目共睹的成绩。为进一步适应住培现状,符合全国儿科培训需求,提高儿科培训质量,儿科专业委员会组织专家代表集思广益,对儿科《住院医师规范化培训基地认定标准》和《住院医师规范化培训内容与标准》两个标准进行适当修订。修订标准遵循两个标准的延续性、可及性、先进性和一致性原则。主要聚焦降低基地规模、提出专业组概念、灵活专业轮转、强化分层培训等,以期在床位规模等不提高前提下,能提高基地培养住培学员临床科研和教学等综合能力。相信通过良好政策引导和支持、医教协同,儿科住培体系将为儿科医学人才培养提供坚实基础。     

硫酸氢氯吡格雷亚微乳注射液的制备及其性质考察

目的:制备硫酸氢氯吡格雷亚微乳注射液,并对其性质进行考察。方法:以注射用大豆油和注射用中链脂肪酸三酰甘油为混合油相,以蛋黄卵磷脂、泊洛沙姆188和聚山梨酯-80为复合乳化剂,采用高压均质法制备硫酸氢氯吡格雷亚微乳注射液,通过粒度和粒度分布、Zeta电位、pH值、渗透压和含量测定以及稳定性考察等对其性质进行研究。结果:制备的乳剂外观为乳白色,略带蓝色乳光。3批样品的粒径分别为(158±22)、(160±22)和(161±33)nm,平均Zeta电位为(-37.70±0.79)mV,平均pH值为(7.51±0.03),平均渗透压为(279.33±0.58)mmol.kg-1,平均含量为(99.19±1.68)%,在(6±2)和(25±2)℃条件下放置6个月稳定。结论:制备工艺可行,制剂理化性质稳定,符合静脉注射要求。