湿热交换过滤器的功能及其并发症研究进展

背景 湿热交换过滤器是一类用于代替上呼吸道和鼻功能的人工装置,具有一定程度的保温、保湿和滤过功能.目的 概述湿热交换过滤器及其并发症,为临床医师的合理选择和使用提供参考.内容 通过总结大量的临床和实验室研究文献,客观地讲述呼吸过滤器的三大功能及其影响因素,同时也详细地介绍了可能发生的并发症.趋向 随着临床和实验室研究的深入,湿热交换过滤器会得到进一步的改进和完善.     

Microclimate and development of pressure ulcers and superficial skin changes

This study aims to evaluate the microclimate and development of pressure ulcers and superficial skin changes. A prospective cohort study was conducted in an acute care ward in Indonesia. Risk factors for pressure ulcers and superficial skin changes were identified based on the Bergstrom Braden conceptual model. Microclimate data were collected every 3 days for 15 days while the development of pressure ulcers and superficial skin changes was observed every day. Pressure ulcers and superficial skin changes were developed in 20 of the 71 participants. Total mean difference in skin temperature was higher for patients with pressure ulcers and superficial skin changes (0·9 ± 0·6°C) compared with controls (0·6 ± 0·8°C) (P = 0·071). Binary logistic regression predictor values for pressure ulcers and superficial skin changes were 0·111 for type of sheet and 0·347 for Braden Scale results. In conclusion, difference in skin temperature seems to be a predictor for pressure ulcer development and superficial skin changes, while synthetic fibre sheets are able to maintain a beneficial microclimate.     

表面水分和不同种类的手套对于硅橡胶印模材聚合时间的影响

目的:本文研究了表面水分和不同种类的手套对于硅橡胶印膜材料聚合时间的影响.方法:使用3种手套:一次性聚乙烯塑料薄膜手套,灭菌橡胶医用手套(无粉),以及橡胶检查手套(预撒粉),分别在潮湿和干燥环境下手动混合DENT SILICONE-PLUS重体型硅橡咬印模材,并记录其硬化时间.结果:干燥情况下使用塑料薄膜手套时,橡胶印模材聚合时间最短,平均2分10秒;乳胶材料和表面水分均可延长聚合时间,达到3～分钟时间;而预撒粉则可显著延长聚合时间,超过1小时.结论:临床运用硅橡胶制取印模时,建议使用一次性聚乙烯塑料薄膜手套在干燥环境下进行操作,预撒粉的橡胶检查手套必须更换,以避免操作失败.     

快速水分测定法测定光慈姑药材水分含量

目的:考察快速水分测定法的影响因素,为其替代烘干法测定光慈姑药材的水分含量提供科学依据。方法:通过研究光慈姑药材的粒度、测定温度及样品质量,得出最优快速水分测定条件,并在最优条件下与烘干法测定结果进行对比。结果:快速水分测定法在最优条件粒度80目以下、温度155℃、样品质量3.0 g,所测光慈姑药材水分与烘干法差异无统计学意义。结论:快速水分测定法操作简便、测定迅速,可替代烘干法测定光慈姑药材的水分含量。     

甘油浓度对红细胞冻干保存效果的影响

目的探讨甘油浓度浓度对红细胞冷冻干燥保存的回收率、溶血率及残余水含量的关系。方法以甘油浓度分别为3%、6%、9%、12%、15%、18%、21%(w/v)的冻干保护剂处理红细胞,冻干,用显微镜观察细胞形态、血细胞计数仪检测细胞数、分光光度计测定游离血红蛋白量,分析细胞复水后红细胞计数、溶血情况。用热重法测定冻干红细胞水分含量,分析不同保护剂组红细胞的水分含量变化情况。结果复水后红细胞形态正常,甘油浓度为9%、12%、15%时,红细胞回收率分别为(77.08±9.41)%、(84.37±3.42)%、(80.21±9.20)%,红细胞溶血率分别为(19.82±2.23)%、(17.66±1.17)%、(15.86±2.23)%,相应的冻干红细胞残余水分含量为(19.43±1.36)%、(22.89±1.57)%、(26.17±1.09)%。结论保护剂中甘油浓度影响红细胞冻干保存的效果;甘油浓度为(9-15)%时对冻干保存的红细胞损伤较小;冻干红细胞残余水分含量随保护剂中甘油浓度的增高而增高。     

星点设计-效应面法优选糖肾宁颗粒的成型工艺

目的:优选糖肾宁颗粒的成型工艺。方法:以成型性、溶解性、吸湿性及吸湿后外观为指标,通过单因素试验确定辅料种类,采用星点设计-效应面法优选辅料配合比例、用量、润湿剂浓度等成型工艺参数。结果:最佳成型工艺为提取物-糊精-甘露醇(4∶3∶3),加入75%乙醇制软材,干燥温度55℃。总评"归一值"(overall desirability,OD)平均值0.786,与模型方程理论预测值(0.78)的偏差0.8%。制备的颗粒剂合格收率88.44%,溶化时间0.5 min,临界相对湿度约70%,休止角34.8度,堆密度0.49 g·m L-1。结论:优选的成型工艺稳定可行,制备的糖肾宁颗粒具有合格率高、溶化性好、抗吸湿性强的特征,为该制剂的大生产提供参考。     

Effects of Loaded End Distance and Moisture Content on the Behavior of Bolted Connections in Squared and Round Timber Subjected to Tension Parallel to the Grain

This article presents the results of static tests on bolted connections in squared and round timber with inserted steel plates. The experiment evaluates structural timber connections with different distances between the fastener and the loaded end at different moisture contents. Specimens were loaded by tension parallel to the grain and load–deformation diagrams were recorded. Fifty-six specimens with three different distances between the fastener and the loaded end, at different moisture contents, were tested. The results were statistically evaluated using regression analysis, complemented with load–deformation curves, and compared with calculations according to the valid standard for design of timber structures. A decrease in the evaluated load-carrying capacity with increasing moisture content was confirmed experimentally. A slight increase in the evaluated load-carrying capacity with increasing fastener distance from the loaded end was found.     

Ultrasonic measurement of the effects of light irradiation and presence of water on the polymerization of self‐adhesive resin cement

Self‐adhesive resin cements are useful in restorations because they reduce the number of clinical steps involved in the restoration process. This study evaluated, using ultrasonic measurements, the influence of light irradiation and the presence of water on the polymerization behavior and elastic modulus of a self‐adhesive resin cement. A self‐adhesive resin cement (RelyX Unicem 2 Automix) or a resin cement (RelyX ARC) was inserted into a transparent mold on a sample stage, and the presence of water and effect of light‐irradiation were evaluated. The transit time of a sonic wave through the cement disk was divided by the specimen thickness to obtain the sonic velocity, and longitudinal and shear waves were used to determine the elastic modulus. When the resin cements were light‐irradiated, the sonic velocity rapidly increased and plateaued at 2,500–2,700 m s^?1. When the cements were not irradiated, the rates of increase in the sonic velocity were reduced. When water was applied to the sample stage, the sonic velocity was reduced. The elastic modulus values of the specimens ranged from 9.9 to 15.9 GPa after 24 h. The polymerization behavior of self‐adhesive resin cements is affected by the polymerization mode and the presence of water.