共查询到20条相似文献,搜索用时 62 毫秒
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用光谱法研究光敏剂血卟啉单甲醚对肿瘤细胞光动力作用的分子机制 总被引:1,自引:0,他引:1
测定了光敏剂血卟啉单甲醚对人宫颈癌细胞HeLa光敏作用后的傅里叶红外光谱。结果显示:光敏作用后,HeLa细胞磷酸二酯基团的对称伸缩振动峰1085cm-1和不对称伸缩振动峰1246cm-1蓝移,强度下降:蛋白质酰胺Ⅰ带1656cm-1发生蓝移,酰胺Ⅱ带1546cm-1出现红移;CH2对称伸缩振动峰2858cm-1,峰位蓝移2cm-1,峰值明显减弱:细胞的蛋白质和核酸谱峰面积比值D1085/D1546降低。提示细胞中的DNA、蛋白质和磷脂结构受到损伤。结果表明:DNA、蛋白质和磷脂是血卟啉单甲醚光敏作用的主要靶分子。 相似文献
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单个肝癌细胞的拉曼光谱分析研究 总被引:1,自引:0,他引:1
本工作利用激光镊子拉曼光谱系统研究了人正常肝细胞株(LO2)和肝癌细胞株(SMMC-7721)的单细胞拉曼光谱,对于每个细胞在不同部位测三个点.实验结果显示:正常细胞和癌细胞的平均拉曼光谱存在显著差异;癌细胞谱线强度整体变弱;正常细胞的1658cm-1处峰和1450cm-1处峰的强度比值为0.63,癌细胞的为0.99;癌细胞的核酸、蛋白质、脂类等重要生物分子在结构或含量上都发生了不同的改变.用PCA主成分对单个细胞的平均拉曼光谱进行分析,结果发现PCA可以正确区分出正常细胞和癌细胞.这些结果表明,激光镊子拉曼光谱是判断正常肝细胞和肝癌细胞的有效方法. 相似文献
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在光敏剂浓度和光剂量一定的条件下,利用拉曼光谱技术研究光敏剂不同孵育时间对C6胶质瘤细胞光动力杀伤效应。实验分5个实验组(光敏剂孵育时间1 h,3 h,6 h,9 h和1个对照组),采集5组C6胶质瘤细胞的拉曼光谱。结果显示:与核酸和蛋白质相关的谱线,峰强和峰位都有很大的变化,孵育时间为1 h的谱线,各峰强度变化较小;孵育时间为6 h的谱线,各峰强度变化最大;孵育时间为9 h的谱线,各峰强度变化进入平台期。实验结果表明:在一定的时间范围内,光动力作用对C6胶质瘤细胞光动力杀伤效应,与光敏剂孵育时间成正相关 相似文献
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血卟啉单甲醚细胞内分布的荧光显微成像 总被引:3,自引:0,他引:3
目的 :探索将荧光显微成像应用于血卟啉单甲醚 (HMME)细胞内分布研究 ;方法 :应用倒置荧光显微镜和致冷IC CD分别采集HMME在人体食管癌细胞和鼠肺毛细血管内皮细胞内的荧光显微数字图像 ,并在计算机中进行图像处理 ;结果 :不同浓度和不同时间下 ,HMME在两种细胞中均主要分布于胞浆及其中各细胞器内 ,而在细胞核内几乎无分布 ;结论 :倒置荧光显微镜和高灵敏度致冷ICCD可有效应用于低荧光效率光敏剂细胞内分布研究 ;细胞核不是HMME在两种细胞内的主要定位点 ,因此不是HMME介导光敏损伤的主要靶点 相似文献
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PNQ_3荧光分光光度计测定HpD对胚胎组织的亲和作用 总被引:1,自引:0,他引:1
光敏疗法诊治癌肿已被人们重视和应用,其作用机理是由血卟啉(简称HpD)对癌细胞有较强的亲和力,经特定波长的光激发后,在一系列动力学反应过程中产生单态氧。这种单态氧具有强烈的氧化能力,有杀死癌细胞的作用。Frank在1948年的研究中发现卟啉对胚眙组织和肿瘤组织同样有较强的亲和力。但未见血卟啉衍生物HpD是否也有类似作用的报道。为此本文设想通过用PNQ_3荧光分光光度计测定HpD在胚胎组织中的荧光光谱峰值,籍以阐明其亲和作用,从而为探索光敏疗法终止早期妊娠的可能性提供理论依据。 相似文献
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质粒pUC18DNA的傅立叶变换拉曼光谱研究 总被引:1,自引:0,他引:1
用傅立叶变换拉曼光谱研究了质粒pUC18DNA的结构。其肿氧核糖-磷酸主链中各振动模式产生的谱带强度相对较强,包括884cm^-1处的脱氧核糖-磷酸主链振动谱带、1459cm^-1处的-CH2弯曲振动谱带和2939cm^-1处的C-H伸缩振动谱带等,而各碱基振动谱带的相对强度则非常弱。 相似文献
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活体糖尿病小鼠中单个白细胞的拉曼光谱分析 总被引:1,自引:1,他引:0
利用拉曼光镊并结合多元统计分析方法无损地对活体糖尿病(DM)小鼠中的白细胞(WBC)进行了研究,分别检测了糖尿病和正常小鼠活体中的白细胞拉曼光谱,利用主成分分析(PCA)建立拉曼光谱诊断多元统计算法模型。结果表明,患糖尿病小鼠和正常小鼠白细胞拉曼光谱差别明显,且实验存在较好的重现性。利用PCA统计分析方法得到诊断特异性和灵敏度达到了98%。在活体糖尿病小鼠白细胞中出现较高的蛋白质的特征峰1302cm-1,表明活体糖尿病白细胞中的蛋白质浓度比正常状态高。糖尿病小鼠内的白细胞与正常相比,DNA磷酸骨架基团强度和蛋白质酰胺强度升高,表明DNA双螺旋结构、蛋白质主链和氢键体系发生变化,二级构象改变。 相似文献
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Meihua Shen Wilfred Pau Nicolas Gani Jianping Wen Shashank Deshmukh Thorsten Lill Jian Zhang Hanming Wu Guqing Xing 《半导体技术》2004,29(8)
This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration. 相似文献
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White organic light-emitting devices based on fac tris(2- phenylpyridine) iridium sensitized 5,6,11,12-tetraphenylnap -hthacene 总被引:1,自引:0,他引:1
We have fabricated the white organic light-emitting devices (WOLEDs) based on 4,4' -bis(2,2 -diphenyl vinyl)-1,1' - biphenyl (DPVBi) and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene (rubrene). The device structure is ITO/2T-NATA (20 nm)/NPBX (20 nm)/CBP: x%Ir(ppy)3:0.5% rubrene (8 nm)/NPBX (5 nm)/DPVBi (30 nm)/Alq(30 nm)/LiF(0.5 nm)/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris (2-phenylpyridine) iridium [Ir(ppy)3], acts as a yellow light-emitting layer, and N,N' -bis- (1-naphthyl)- N,N' -diphenyl -1, 1' -biphenyl-4,4' -diamine (NPBX) acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir (PPY)3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V. 相似文献
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Complete approach to automatic identification and subpixel center location for ellipse feature 总被引:1,自引:0,他引:1
XUE Ting WU Bin SUN Mei YE Sheng-hua 《光电子快报》2008,4(1):51-54
To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction. 相似文献
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Credence Systems Corporation 《半导体技术》2004,29(9)
Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V. 相似文献
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It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer (LDV). 相似文献
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Zhang Xinsheng 《中国通信》2014,(1)
正Happy New Year!As we step into a new year,we take a look back at the key feature topics covered in China Communications over the past 12 months and set out our expecta- 相似文献
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正For a long time,optical and wireless systems/net-works are developed in separate communities witha few attempts for in-depth convergence.In fact,it prom-ises many advantages to combine the optical and wire-less technologies in the levels of systems and networks.Recently,both academia and industry have made manyefforts to enter a new phase of development to take op-tical and wireless systems as fully integrated networks.To provide high bandwidth and reliable service for bothfixed and mobile users,a well-designed network must 相似文献
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