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91.
葡甘聚糖-胶原蛋白-壳聚糖共混膜(I)   总被引:2,自引:0,他引:2  
用溶液共混法制备了葡甘聚糖-胶原蛋白-壳聚糖(KCCS)共混膜。并用FT-IR,X-RD,SEM及透光率表征了膜的结构,同时测试了膜的抗张强度、断裂伸长率、吸水率、透水汽性、渗透性和吸附性。结果表明:共混膜中葡甘聚糖、胶原蛋白及壳聚糖之间存在着强烈的相互作用和良好的相容性,三者共混明显改善了纯聚合物和二元膜的性能。以共混膜为载体培养内皮细胞,发现共混膜具有良好的细胞相容性,预示着共混膜可作为潜在的组织工程支架材料。  相似文献   
92.
本文采用数值计算手段,模拟普通的圆柱形单孔结构和小孔辅助射流结构在不同吹风比下的流动和换热,侧重通过直观演示气膜孔下游反向对旋涡对(肾形涡)的生成、发展以及相互作用过程,揭示小孔辅助射流改善气膜冷却效果的机理。结果表明:与单孔结构相比,小孔辅助射流结构,由于小孔射流的干涉作用,主孔射流形成的肾形涡的尺度和强度均有较大程度的减小,冷气射流与主流的掺混减弱,对冷气的向上抬升作用减小,避免了冷气穿透主流脱离壁面,大大提高冷效。随着吹风比的增加,与圆柱形单孔相比,气膜冷却效果改善更加明显。  相似文献   
93.
An electrochemically deposited indium(III)-hexacyanoferrate (InHCF) film on glassy carbon and platinum electrodes has been investigated by X-ray photoelectron spectroscopy (XPS). Attempts were made to characterise such a polynuclear inorganic film upon its electrochemical conditioning in both reduced and oxidised forms. The indium ions were unaffected by the oxidation state of the film and were present mainly as In(III). In the oxidised form (i.e. conditioned at +0.90 V) the InHCF is unstable during XPS analysis, with Fe being reduced from FeIII to FeII. Profound alterations were also observed in the chemical form of nitrogen. Although the InHCF film was grown in potassium containing solutions, a very low amount of K+ ions was incorporated into the inorganic lattice. This fact, along with the iron to indium ratio of 0.76±0.06 (n=6), is consistent with a potassium-free structure of `insoluble' In4[Fe(CN)6]3 · xH2O. Yet the stability of InHCF films is not very good, and the electrochemical formation of InFe(CN)6 and KInFe(CN)6 is probably the main cause of the film dissolution.  相似文献   
94.
This is the first study of micro-autoradiography (micro-ARG) for [18F]2-fluoro-2-deoxy- -glucose ([18F]FDG). The localization of [18F]FDG was demonstrated in dendrites of neuron and also in the myelinated axon in mouse normal brain in vivo. The nucleolus was relatively free of label. The counted silver grain numbers in autoradiogram were linearly correlated to the 18F radioactivities in the specimen. The micro-ARG using positron emitting 18F is a very time-saving technique with 4 hours exposure compared with the conventional method using 3H- or 14C-labeled tracers.  相似文献   
95.
Using a flexible piezoelectric film, the authors developed a simple system to determine noninvasively the heart rate of chicken embryos and hatchlings. The film was piezoelectric polyvinylidene fluoride (PVDF), which is sensitive enough to detect cardiogenic ballistic movements of the egg (ballistocardiogram (BCG)) and precordial movements of the hatchling attributable to cardiac contractions (apexcardiogram (ACG)). The BCG could be detected, during the second half of incubation, by placing the egg on the PVDF film on a soft substrate. The detected signal was found to be a measure of movement velocity. The ACG could be measured when the hatchling's chest wall made contact with the PVDF film installed in a box in which the hatchling was confined. The heart rate was counted from the lag time of autocorrelation calculated for a certain time segment (e.g. 2s) of the BCG and ACG recordings.  相似文献   
96.
目的探讨数字根尖片在术前评估根管内折断器械取出难度和根管侧穿发生中的应用价值。方法应用分角投照技术拍摄的患牙数字根尖片,对2007年4月至2008年10月于烟台市口腔医院特需门诊就诊接受显微超声取根管内折断器械的病例47例进行分析,分析其折断器械在根管内的位置与折断器械取出成功率和根管侧穿发生率的关系。结果当折断器械位于根尖1/3时,应用显微超声技术取出的成功率和根管侧穿发生率分别为36.84%和52.63%,而器械位于根管冠1/3、中1/3时取出成功率分别为90.00%、88.89%,根管侧穿发生率分别为10.00%、11.11%;当折断器械位于弯曲根管以上或以下时器械取出的成功率分别为88.46%和42.86%,根管侧穿的发生率分别为11.54%和47.62%。结论分角投照数字根尖片在术前分析根管内折断器械取出的成功率和根管侧穿的发生具有较高的参考价值,可作为根管内折断器械病例术前难度评估和预测侧穿发生的常规方法。  相似文献   
97.
白内障手术切口对眼表影响的研究   总被引:1,自引:0,他引:1  
张司  李一壮 《国际眼科杂志》2010,10(9):1719-1721
白内障术后部分患者出现术眼角膜知觉的减退、干涩感、异物感、烧灼感等眼部不适症状,以及手术切口对泪膜产生的影响。我们就其病因及发病机制及处理进行系统的分析,期待对临床上白内障手术方法的选择,降低和减少术后并发症有一定的指导意义。  相似文献   
98.
目的:探讨LD-A数码医疗纸介质打印系统在磁共振影像学诊断腔隙性脑梗死方面的临床应用价值。方法:请3名具有5年以上磁共振阅片经验的医师回顾性分析经磁共振确诊为腔隙性脑梗死患者的纸介质打印片和胶片结果。结果:分析100例腔隙性脑梗死患者影像图像,经统计学处理,诊断结论无统计学意义,证明这两种方式读片时结果无显著性差异。结论:LD-A数码医疗影像成像系统在磁共振对于腔隙性脑梗死患者的临床诊断上有应用价值。  相似文献   
99.
X线照片斑点的自相关函数的测试探讨   总被引:2,自引:0,他引:2  
目的:测试X线照片斑点的自相关函数(auto-corelationfunction,ACF)。材料与方法:对Fuji(CaWO4),Fuji(BaFClEu),天津X线胶片(CaWO4)和天津X线胶片(BaFClEu)4种屏-片组合系统,在同一摄影条件下获得X线照片,用显微密度计对其进行扫描取得X线照片的密度分布曲线D(X),作为离散型随机信号来处理,计算出4种屏-片系统的X线照片斑点的ACF值。结果:与BaFClEu组合的X线照片斑点的ACF值比与CaWO4组合的屏片系统的大。结论:BaFClEu增感屏因结构颗粒大,对X线照片影响大(或相关性强),控制X线照片斑点ACF值的主要措施是,使增感屏的颗粒不宜过大。  相似文献   
100.
《Radiography》2023,29(2):408-415
IntroductionRadiographers can accurately report musculoskeletal and chest radiographs, but there is paucity of research comparing the performance of reporting radiographers (RRs) with consultant radiologists when interpreting and reporting abdominal radiographs. This study assessed interobserver agreement in the clinical setting between reporting radiographers and a consultant radiologist compared to an expert gastrointestinal radiologist in a District General Hospital. Major discordant reports affecting patient management were also examined.Methods126 abdominal radiographs reported by 3 RRs in clinical practice were randomly selected and reported by a consultant radiologist and index gastrointestinal radiologist. The reports of the RRs and consultant radiologist were compared against the reports made by the index radiologist for agreement by a colorectal consultant surgeon. All 126 reports were scored as being in either complete agreement, minor disagreement or major disagreement which would have resulted in a change to patient management.ResultsThere was no significant difference in overall agreement between the consultant radiologist (CR) and RRs when compared to the index radiologist (CR: n = 90/126, 71.4% and RRs: n = 94/126, 74.6%. p = 0.57). Major disagreements were found, but there was no significant difference between both groups (CR: n = 23/126, 18.3% and RRs: n = 17/126, 13.5%. p = 0.30).ConclusionRRs can report abdominal radiographs to a comparable level of agreement as a consultant radiologist in the clinical setting. There was no significant difference in reports deemed to affect patient management.Implications for practiceThis study addresses the gap in assessing the performance of RRs reporting abdominal radiographs. This small scale study indicates that radiographers could provide additional support in the reporting of abdominal radiographs. This would help to reduce radiologist workload and enhance the role of the reporting radiographer.ClassificationAgreement between reporting radiographers and radiologists interpreting and reporting abdominal radiographs.  相似文献   
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