视网膜色素上皮DNA蓝光损伤及维生素E的保护作用

目的：探讨维生素E对视网膜色素上皮DNA蓝光损伤的保护作用。方法：视网膜色素上皮细胞分为3组：正常组（不照光），实验组（蓝光照射40min），维生素E组（蓝光照射同时给予维生素E）。采用火箭电泳的方法对各组视网膜色素上皮DNA损伤进行分析。结果：各组火箭电泳尾部DNA含量分别为18．44％，54．42％和22．16％。各组差异有显著性意义（P＜0．01）。结论：蓝光能对视网膜色素上皮的DNA产生损伤，维生素E对损伤能起到一定的保护作用。     

Comparison of two methods of estimation of low density lipoprotein cholesterol, the direct versus friedewald estimation

Current recommendations of the Adult Treatment Panel and Adolescents Treatment Panel of National Cholesterol Education Program make the low-density lipoprotein cholesterol (LDL-C) levels in serum the basis of classification and management of hypercholesterolemia. A number of direct homogenous assays based on surfactant/solubility principles have evolved in the recent past. This has made LDL-C estimation less cumbersome than the earlier used methods. Here we compared one of the direct homogenous assays with the widely used Friedewald’s method of estimation of LDL-C to see the differences and correlation. We used direct homogenous assay kit to estimate serum LDL-C and high-density lipoprotein cholesterol (HDL-C). Serum Triglyceride (TG) and Total Cholesterol (TC) was estimated and using Friedewald’s formula LDL-C was calculated. The LDL-C level obtained by both methods in 893 fasting serum samples were compared. The statistical methods used were paired t-test and Pearson’s correlation. There was significant difference in the mean LDL-C levels obtained by the two methods at the TG levels <200 mg/dl (p<0.02) and TC levels >150 mg% (p<0.001). The correlation coefficient (r) between Friedewald’s and direct assay estimation was 0.88. Friedewald’s method classified 23.5 % of patients as high cardiac risk whereas there were 17.58% by direct assay. Both had good correlation even though the serum triglyceride and total cholesterol levels affect the difference in LDL-C estimated by both methods. Taking into account the cost and performance, Friedewald’s method is as good or even better for classifying and managing patients.     

碱性苦味酸法和酶法测血清肌酐的方法学比较

[目的]了解酶法和碱性苦味酸法测定血清肌酐结果的偏倚大小,对两种方法进行比较.[方法]用生化仪器OLYMPUSAU1000分别进行酶法和碱性苦味酸法测定血清肌酐.对两种方法进行重复性实验、相关性实验、线性比较和回收试验.[结果]酶法和碱性苦味酸法的重复性实验数据(x±s)266±2.77μmol／L和273.5±3.30μmol／L,其变异系数分别为1.04％、1.21％;两者的回归方程式yJaffe=1.01X二步酶法-1.28;酶法的线形范围远大于碱性苦味酸法;在回收试验中两者的回收率分别为98.5％、94.5%.[结论]酶法和苦味酸法有较好的相关性,酶法比碱性苦味酸法线性范围宽,特异性和灵敏度高,测定重复性好,是比较理想的方法.临床上酶法将逐渐代替苦味酸法测定血清肌酐.     

素质与素质教育:理性拷问与多元建构

素质教育要突破当下被边缘化的困境,首先要对素质教育作出比较科学的定义,要对素质教育作出比较科学的定义,又必须首先对素质作出比较科学的定义。所谓素质是指:内化在个体身上的,由知识、能力和技能构成的能够迅速地发现和解决现实生活中的难题,并创造出个体或社会所需要的物质或精神产品的品质。     

稀土和磷对过共晶Al-Si合金的复合变质作用

The effect of rare earth (RE) elements on the morphologies and sizes of Si phases in the hypereutectic Al-Si alloys modified with P was investigated.The results show that the addition of La element to the hypereutectic Al-Si alloys can enhance the effect of P element on the modification of the primary Si phases.In the multiplex modification of RE-P,the primary Si phase is refiner and the shape of the eutectic Si is changed from long needle-like to short rod-like.Moreover,the agglomeration rate of the primary Si phase is slowed greatly.Even the melt is held for 6 h,the average size of the primary Si phase is still satisfied.The results analyzed by scanning electron microscope (SEM) indicate that La is richer at A1-Si interface than that inα-Al or primary Si phase.The higher the La content in the Al-Si interface,the smaller the primary Si phase.     

小区级数字视频服务器的设计与实现

研究了VOD系统的关键系统之一的视频服务器系统,提出了低复杂度视频服务器的全套实现方案。系统复用后传输流符合相应DVB规范并可以被机顶盒正确接收。本视频服务器方案有很好的性价比,提供了灵活的用户接口界面,可以方便的嵌入实用系统。     

Kinetic analysis of γ-glutamyltransferase reaction process for measuring activity via an integration strategy at low concentrations of γ-glutamyl p-nitroaniline

At 0.12 mmol/L γ-glutamyl p-nitroaniline (GGPNA), an improved integrated method was developed for kinetic analysis of γ-glutamyltransferase (GGT) reaction process and the integration with the classical initial rate method to measure serum GGT. For the improved integrated method, an integrated rate equation, which used the predictor variable of reaction time and considered inhibitions by both GGPNA and products, was nonlinearly fit to GGT reaction processes. For the integration strategy, classical initial rates were estimated when GGPNA consumption percentages were below 50%; otherwise, maximal reaction rates of GGT were estimated by the improved integrated method and converted into initial rates according to the differential rate equation at 0.11 mmol/L GGPNA. The integration strategy was validated using optimized GGT kinetic parameters and 10-s intervals to record reaction curves within 8.0 min. By the integration strategy, there was a linear response from 0.9 to 32.0 U/L GGT, coefficients of variation were below 3.5% for GGT from 8.0 to 32.0 U/L (n=5), and GGT activities in clinical sera responded linearly to their classical initial rates at 2.00 mmol/L GGPNA with an expected slope. Therefore, the integration strategy was successful in measuring GGT at 0.12 mmol/L GGPNA.     

Stomatocyte structural color-barcode micromotors for multiplex assays

Artificial micromotors have a demonstrated value in the biomedical area. Attempts to develop this technology tend to impart micromotors with novel functions to improve the values. Herein, we present novel structural color-barcode micromotors for the multiplex assays. We found that, by rapidly extracting solvent and assembling monodispersed nanoparticles in droplets, it could form stomatocyte colloidal crystal clusters, which not only showed striking structural colors and characteristic reflection peaks due to their ordered nanoparticles arrangement, but also provided effective cavities for the integration of functional elements. Thus, the micromotors with catalysts or magnetic elements in their cavities, as well as with the corresponding structural color coding, could be achieved by using the platinum and ferric oxide dispersed pre-gel to fill and duplicate the stomatocyte colloidal crystal clusters. We have demonstrated that the self-movement of these structural color-barcode micromotors could efficiently accelerate the mixing speed of the detection sample and greatly increase the probe–target interactions towards faster and more sensitive single or multiplex detection, and the magnetism of these barcode micromotors enables the flexible collection of the micromotors, which could facilitate the detection processes. These features make the stomatocyte structural color-barcode micromotors ideal for biomedical applications.     

工程硕士培养及管理特点分析

工程硕士的培养目标是培养工程实践者。社会经济的发展催生了工程硕士这一教育形式的产生,高等院校顺应社会发展需要,针对工程硕士培养的特点,培养工程技术领域掌握前沿科学知识同时具有综合管理素质的高层次、复合型人才。为在职人员提供进一步深造的机会同时满足社会对高素质人才的需求。