Hydration of surfactant-modified and PEGylated cationic cholesterol-based liposomes and corresponding lipoplexes by monitoring a fluorescent probe and the dielectric relaxation time

For the optimization of plasmid DNA (pDNA)-cationic lipid complexes and lipoplex delivery, proper indexes of the physicochemical properties of lipoplexes are required. In general, the characteristics of lipoplexes are defined by particle size and zeta-potential at various mixing ratios of cationic liposomes and pDNA. In this study, we characterized the hydration level of surfactant-modified and PEGylated cationic cholesterol-based (OH-Chol) liposomes and their lipoplexes by monitoring both the fluorescent probe laurdan and the dielectric relaxation time. Fluorescence measurement using laurdan detected hydration of the headgroup of lipids in surfactant-modified liposomes and PEGylated DOTAP-liposomes, but hardly any fluorescence was detected in PEGylated OH-Chol-liposomes because the PEG layers may extend and cover the fluorescent maker. On the other hand, the measurement of dielectric relaxation time of water molecules revealed total hydration, including hydration of the PEG layer and the headgroup of cationic lipids. Furthermore, we found an inverse correlation between hydration level and cellular uptake of PEGylated lipoplexes (R=0.946). This finding indicated that the dielectric relaxation time of water molecules provides an important indicator of hydration of liposome and lipoplexes along with the fluorescence intensity of laurdan.     

Vitallium 2000与钛合金铸造支架义齿的临床应用比较

目的评估Vitallium2000铸造支架义齿的临床应用效果。方法把175例牙列缺损的患者通过80例Vitalli—UIll2000支架义齿和95例钛合金支架义齿修复,比较两组患者的满意度。结果Vitallium2000支架义齿与钛合金支架义齿相比而言,患者在美观性、舒适度、语言功能方面的满意度高（P〈0．05）。结论Vitallium2000铸造支架义齿临床修复效果优于钛合金。     

Authentication and Self-Correction in Sequential MRI Slices

One of the new challenges of Information Technology in the medical world is the protection and authentication of a variety of digital medical files, datasets, and images. In this work, the ability of magnetic resonance imaging (MRI) slice sequences to hide digital data is investigated and more specifically the case that the hidden data are the regions of interest (ROI) of the MRI slices. The regions of non-interest (RONI) are used as cover. The hiding capacity of the whole sequence is taken into account. Any ROI-targeted tampering attempt can be detected, and the original image can be self-restored (under certain conditions) by extracting the ROI from the RONI.     

Using JPEG 2000 Interactive Protocol to Stream a Large Image or a Large Image Set

The electronic health record (EHR) is expected to improve the quality of care by enabling access to relevant information at the diagnostic decision moment. During deployment efforts for including images in the EHR, a main challenge has come up from the need to compare old images with current ones. When old images reside in a different system, they need to be imported for visualization which leads to a problem related to persistency management and information consistency. A solution consisting in avoiding image import is achievable with image streaming. In this paper we present, evaluate, and discuss two medical-specific streaming use cases: displaying a large image such as a digital mammography image and displaying a large set of relatively small images such as a large CT series.     

Comparison of the safety and immunogenicity of ACAM1000, ACAM2000 and Dryvax in healthy vaccinia-naive adults

Currently, more than half of the world's population has no immunity against smallpox variola major virus. This phase I double-blind, randomized trial was conducted to compare the safety and immunogenicity of two clonally derived, cell-culture manufactured vaccinia strains, ACAM1000 and ACAM2000, to the parent vaccine, Dryvax^®. Thirty vaccinia-naïve subjects were enrolled into each of three groups and vaccines were administered percutaneously using a bifurcated needle at a dose of 1.0 × 10⁸ PFU/mL. All subjects had a primary skin reaction indicating a successful vaccination. The adverse events, 4-fold neutralizing antibody rise and T cell immune responses were similar between the groups.     

实施ISO9001 6年回顾

回顾实施ISO9001质量管理体系对医院关键指标的影响,总结保持ISO9001质量管理体系的主要做法.统计关键指标;回顾如何保持ISO9001质量管理体系的完整性、持续性、适宜性、有效性、创新性.实施ISO9001质量管理体系明显改善了医院主要业绩指标;坚持"原则"才能保持体系的完整性,驱动"三审"才能保持体系的持续性,适时改版才能保持体系的适宜性,持续改进才能保持体系的有效性,联系实际才能保持体系的创新性.精心构建、实施和保持ISO9000质量管理体系,以患者为导向,充分尊重和依靠员工,就一定能谱写医疗质量管理的新篇章.     

放射免疫法免疫比浊法及免疫试纸定性法检测尿微量白蛋白比较分析

目的比较3种尿微量白蛋白检测方法即免疫试纸定性法(Micral-Test)、免疫比浊法(DCA2000分析仪)和放射免疫法检测结果的一致性,评价其诊断价值。方法2003年9月至2005年5月收集中山大学附属第一医院应用Micral-Test试纸结果阳性或可疑阳性的133例糖尿病患者,留取随机尿和过夜8h尿进行Micral-Test试纸定性法、放射免疫法和DCA2000分析仪3种方法检测尿微量白蛋白。结果(1)放射免疫法尿微量白蛋白浓度质量(Alb)和尿微量白蛋白排泄率(AER)的检测值明显低于DCA2000分析仪(P<0.01),后者AER的灵敏度和特异度分别为100%和86.2%,κ=0.812。(2)随机尿和过夜尿的Micral-Test试纸判读结果ROC曲线下面积(AUC):0.900对0.934。(3)随机尿尿微量白蛋白与尿肌酐比值(ACR)和Alb的AUC分别为0.952对0.923;而过夜尿ACR和Alb的AUC分别为0.965对0.958。结论3种尿微量白蛋白检测方法的诊断价值均较高。Micral-Test试纸适用于尿微量白蛋白初步筛选,尿ACR尚不能代替尿AER作为诊断标准,DCA2000分析仪较放射免疫法精确。     

基于兴趣区的编码方法探讨

目的探讨JPEG2000标准中基于兴趣区的编码方法，重点讨论了标准中的最大上移方法。方法最大上移方法缩放兴趣区的系数，使得属于兴趣区的所有信息在码流中放在背景区的信息之前。改变图像的量化方式和码流截断点的位置，就能获得不同质量的兴趣区和背景区。结果在低比特率(大约小于0．05bpp)时，兴趣区和背景区具有近似的图像质量。随着比特率的增加，兴趣区的质量迅速提高。结论最大上移方法处理任意形状的兴趣区时，不需要编码形状，解码器既不用解码形状，也不需要生成兴趣区掩膜，因此更加简单。     

急性中毒患者的相关因素分析与救护

目的探讨急性中毒患者的相关因素和救护。方法对98例急性中毒病人有关资料进行回顾性分析计数归类,应用χ^2进行统计学处理。结果本组患者服用毒类类别、发病季节与其生活区域有显著差异（P〈0.01）;服毒原因与性别有显著差异（P〈0.001）;急性中毒以服毒自杀的青壮年居多,而误服者以农村留守儿童为主。结论加强农村农药及镇静催眠药物的管理和对留守儿童人文关怀,加强社区女性人群及季节性健康教育是控制急性中毒发生的有效措施。     

ASIA2000标准信度初步分析

目的测定ASIA2000标准的重测信度和评测者间一致性。方法对我院2004年4月在院的脊髓损伤患者按照入选标准筛选出25例进行信度分析，由同一检查者于第1次记录后1周使用ASIA2000标准进行再次评定，测定重测信度。同一组患者由另一名专科医师于第1次记录后24h进行检查，测定评定者间一致性。结果重测信度为，针刺觉评分、触觉评分、运动评分的Pearson相关系数均〉0．90（P〈0．05）；残损分级和损伤完全性测定的Kappa值分别为0．787和0．756（P〈0．05）；评测者间一致性为，针刺觉评分、触觉评分、运动评分的Pearson相关系数均〉0．85（P〈00．05）；残损分级和损伤完全性测定的Kappa值分别为0．802和0．764（P〈0．05）。结论ASIA2000标准各项目具有较高的重测信度和评测者间一致性。