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1.
王宇  朱菁  张慧国 《应用激光》2005,25(3):209-210
目的:寻求鼠脑肿瘤注血卟啉后光敏诊治最佳时间。方法:在注HPD后不同时间对正常脑组织和脑肉瘤组织用氙离子激光激发荧光,采用OMA系统分析观察两组的荧光变化。结果:显示注药3小时后小鼠正常脑组织血卟啉荧光峰明显下降而脑肉瘤组织仍保持较高血卟啉浓度。结论:注药后4~5小时是最佳的鼠脑肿瘤光敏诊断及光动力学治疗的时间。  相似文献   

2.
目的:探讨光活化BPD-MA对膀胱癌细胞线粒体膜通透性转运孔的影响。方法:应用流式细胞仪分析光活化BPD-MA后膀胱癌细胞线粒体膜通透性转运孔(permeability transition pore,PTP)的开放状况。结果:激光活化BPD—MA光动力作用后线粒体前向光散射(forward light scatter,FSC)分布峰位置由低道数往高道数移动,FSC增大,线粒体膨胀;Rhodamine123荧光分布峰位置由高道数往低道数移动,荧光强度降低,线粒体膜电位下降;90°侧向光散射(90°light scatter,SSC)分布峰位置由低道数往高道数移动,SSC增大,线粒体颗粒性状发生改变。表明激光活化BPD-MA光动力作用诱导人膀胱癌细胞株BIU-87线粒体膜PTP孔开放,而单纯激光照射和单纯光敏剂BPD-MA处理均无明显影响。结论:激光活化BPD-MA光动力作用导致的PTP开放可能是BPD-MA光动力诱导人膀胱癌细胞株BIU-87凋亡的机制之一。  相似文献   

3.
目的:观察局部氧疗联合封闭负压引流干预促进豚鼠Ⅲ期压疮创面愈合的疗效,并优化其工作参数。方法:实验分疗效对比实验和参数优化实验两部分。疗效对比实验:选取20只清洁级雄性白色豚鼠,在左侧大转子处构建Ⅲ期压疮创面。20个创面随机分为五组:A组(持续-125mmHg负压治疗320min后给予5L/min的局部氧疗160min)、B组(-125mmHg负压治疗40min,5L/min的局部氧疗20min,交替8次)、C组(-125mmHg负压治疗40min后暂停20min,重复8次)、D组(5L/min的局部氧疗20min后暂停40min,重复8次)、E组(对照组)。在创面形成第0、1、3、7、11测量创面面积,计算创面面积收缩率。参数优化实验:构建23只Ⅲ期压疮豚鼠模型,采用均匀实验设计和多元回归分析,考察局部氧疗联合封闭负压引流干预方法的负压强度、氧流量、一小时内局部氧疗的工作时间和干预频次对日平均创面面积收缩率的影响。结果:在相同时相点,局部氧疗和封闭负压引流联合干预组创面面积收缩率均高于单纯负压、氧疗或空白组(P〈0.001),且交替运行方式优于序贯运行方式。最优工作参数为干预频次12次/13、一小时内局部氧疗干预时间50min、封闭负压引流负压强度-125mmHg和局部氧疗氧流量10L/min。结论:局部氧疗和封闭负压引流联合干预方法能显著促进豚鼠Ⅲ期压疮创面愈合。均匀设计和回归模型可以对实验结果进行高精度预测,优化了工作参数。  相似文献   

4.
章沐曦  李立 《激光杂志》2010,(3):86-87,89
目的:研究黄芩苷对兔tenon囊成纤维细胞增殖及TGF-β1表达的影响,初步探讨其对青光眼术后滤过瘢痕的治疗作用。方法:以体外培养的兔tenon囊成纤维细胞为实验对象,分别加入含不同浓度(15,30,45,60μg/m1)黄芩苷培养24,48,72h后采用MTT法检测药物对细胞的抑制率;采用流式细胞术及半定量逆转录聚合酶链反应法(RT-PCR)检测30μg/ml黄芩苷作用48h后成纤维细胞周期情况及TGF-β1的mRNA的变化;结果:MTT法显示黄芩苷各实验组与对照组抑制率间比较差异有显著性;流式细胞术显示黄芩苷将细胞阻抑于G1期;RT-PCR显示药物作用后细胞中TGF-β1的mRNA含量显著降低。结论:黄芩苷可抑制体外培养的兔Tenon囊成纤维细胞增殖,其作用可能跟下调TGF-β1的表达有关。  相似文献   

5.
目的:研究Ar^ 激光对兔眼虹膜凝固的效果。方法:用波长532nm、功率300mW、光斑直径500μm、脉宽0.2S的Ar^ 激光分别对家兔的滴药眼和未滴药眼的虹膜近瞳孔缘处进行环状光凝固。结果:光凝固后,立即测出点药眼和未点药眼的PGE含量和瞳孔径数值差别不大,但两眼前房水混浊消退时间差别显著,结论:Ar^ 激光对虹膜凝固有临床效果。  相似文献   

6.
本文研究心房特殊颗粒(ASG)中的钙释放是否能促进颗粒内容的分泌.冷冻超薄切片技术和磷钨酸-乙醇(EPTA)特殊染色技术制备大鼠心房切片.X射线显微定量分析采用Hall连续谱法,用以测量在肾上腺素处理后15、30、60和120 min时ASG中钙含量的变化.用形态计量法的数密度作为判断ASG分泌状态的指标.结果显示心房特殊颗粒在生理状态下钙浓度高达80 mmol/公斤*干重.在肾上腺素注射后ASG的数密度逐渐下降,并于注射后60 min时下降至最低;ASG中的钙含量亦逐渐减低,但于注射后30 min即达最低,由此可见ASG钙含量的下降出现早于颗粒数的下降.推想肾上腺素处理引起的钙释放可能成为一种信号,启动心房肽的分泌,因此ASG在心房心肌细胞中可能具有细胞内钙库机能.本文同时讨论了Hall连续谱法近年来在生物试样定量分析中的应用和发展.  相似文献   

7.
目的:探讨不同治疗剂量高强度聚焦超声(high intensity focused ultrasound,HIFU)对兔眼晶状体组织形态和弹性变化的影响。方法:184只兔眼球随机分为空白组和HIFU组,空白组未给予HIFU辐照,HIFU组选取功率1、2W分别辐照时间3、5、8、10、15、20、25s;功率3,4、5W分别辐照时间3、5、8、10、15s;辐照完后进行组织学观察以及弹性变化检测。结果:当HIFU剂量较小时,组织学观察可见晶状体辐照区形态规则,呈水滴状;当剂量增大达到一定程度时,辐照区形态不规则,可见空化效应所致大小不等的空泡。HIFU辐照晶状体后导致晶状体弹性发生变化,空白对照组、1W、3s和15s组,2W、15s组,3—5W、8s组两两比较差异无统计学意义(P〉0.05),余各组晶状体变化量均明显低于空白对照组,差异有统计学意义(P〈0.05)。结论:HIFU辐照兔眼晶状体可影响其弹性变化,在一定的能量下空化效应可恢复晶状体的弹性。  相似文献   

8.
目的:探讨汉防己甲素(Tet)对离体兔眼角膜基质细胞抑制增殖作用,及其对增殖率和凋亡率的作用程度比较。方法:选用原代及传代兔角膜基质细胞,实验组加入含不同浓度Tet的培养液,对照组加入含等量PBS的培养液。通过免疫细胞化学技术了解细胞的PCNA表达来枪测细胞增殖情况,计算增殖率并测定变化;流式细胞仪(FCM)测定细胞周期和凋亡率的变化。结果:Tet质量浓度为2μg/ml,3μg/ml,4μg/ml时,作用48h,随着Tet浓度的增大,PCNA阳性细胞数明显减少,角膜基质细胞的增殖率呈递减趋势,存在剂量一效应关系(P〈0.05);FCM结果显示,随着Tet的浓度增大,实验组G0/G1期细胞增加,细胞删期阻滞在G1期,见细胞凋亡峰,凋亡率也随浓度增大而升高(P〈0.05);Tet对增殖率影响的曲线斜率绝对值明显大于对调亡率作用的斜率绝对值,结论:Tet对角膜基质细胞的PCNA的表达具有明显抑制作用,随Tet浓度增大,角膜基质细胞的增殖率下降,Tet通过将细胞阻滞在G1期而发挥其抗增殖作用,且存在剂量效应关系;Tet诱导细胞凋亡,且也存在剂量效应关系,随浓度增大,凋亡率增加;在2μg/ml.3μm/ml,4μg/ml的浓度内,Tet对角膜基质细胞同时具有抑制增殖和诱导凋亡作用,但以抑制增殖作用为主.  相似文献   

9.
激光辐照对不同饵料微藻生长的影响   总被引:5,自引:0,他引:5  
利用Nd:YAG激光(波长1.06μm,功率5W,照射时间0.5-3min)和Ar 激光(波长:488nm,功率70mw,照射时间5-20min)分别照射角毛藻和叉鞭金藻,辐照后进行细胞增殖和生长速率的测定。实验结果表明:照射剂量为1min的Nd:YAG激光及剂量为5min的Ar 激光对叉鞭金藻有较明显的促长效果,这两种激光处理组的细胞增殖量在辐照后的两天内较对照组分别高42.9%和48.1%,但这种促长效果随时间的推移逐渐消失。不同剂量的两种激光辐照角毛藻后,在延滞期均出现生长抑制现象,但进入指数生长期或传代培养后,剂量为1min的Nd:YAG激光及剂量为10min的Ar 激光对角毛藻有明显的促长效果,其中在指数生长期1min剂量的Nd:YAG激光处理可促长27.0%,传代培养后10min的Ar 激光处理组生长速率提高达51.2%。本文对不同激光及不同激光参数条件下,两种饵料藻的耐受性及生长特性的差异也进行分析探讨。本实验结果不仅证实了已有研究的推论,还展示出激光技术在饵料藻种选育中的应用前景。  相似文献   

10.
利用HF酸处理提高石英玻璃355nm激光诱导损伤阈值,通过优化HF溶液浓度以及石英玻璃表面的酸处理时间,石英玻璃的透过率和损伤阈值均有所提高,均随HF酸浓度以及酸处理时间的增加呈现先增加后下降变化。实验结果表明质量分数10%的HF浓度刻蚀60 min后石英玻璃的激光损伤阈值为15.17 J/cm2,相比酸处理前提高了167.5%。对比分析了相同激光能量密度作用下有无HF酸处理石英玻璃表面损伤面积变化,最后给出了HF酸处理提高石英玻璃的激光诱导损伤阈值机制。  相似文献   

11.
BPD-MA光动力作用对膀胱癌细胞凋亡及bcl-2蛋白表达的影响   总被引:3,自引:0,他引:3  
目的:研究激光活化BPD-MA光动力诱导肿瘤细胞凋亡及其可能机制。方法:应用流式细胞仪分析BPD-MA光动力作用后细胞凋亡及免疫组化染色检测凋亡相关蛋白bcl-2蛋白表达水平。结果:激光活化BPD-MA光动力实验组人膀胱癌细胞株BIU-87凋亡发生率达26.11±2.59%,与对照组相比,差异非常显著性(P<0.01);光动力作用后膀胱癌细胞线粒体相关调控蛋白bcl-2表达显著低于对照组(P<0.05)。结论:激光活化BPD-MA光动力作用具有诱导人膀胱癌细胞株BIU-87凋亡的生物效应,而线粒体相关调控蛋白bcl-2表达水平的降低可能是激光活化BPD-MA光动力诱导人膀胱癌细胞株BIU-87凋亡的重要机制之一。  相似文献   

12.
为了研究光动力抑癌作用机制,采用流式细胞仪和TUNEL法检测激光光敏化BPD-MA后人膀胱癌细胞株BIU-87细胞凋亡的发生状况.激光光敏化BPD-MA后人膀胱癌细胞株BIU-87组细胞凋亡发生率明显增高,许多细胞核呈棕黄色,高倍镜下可见细胞核内有大量棕褐色颗粒,与阳性对照中凋亡细胞核的特征相符合,而对照组此种细胞少见.TUNEL阴性对照中细胞核均呈蓝色.结果表明,激光激活BPD-MA光动力作用明显诱导人膀胱癌细胞株BIU-87细胞发生凋亡,这可能是其抑癌作用机制之一.  相似文献   

13.
低功率激光对细胞质膜通透性及细胞功能的影响   总被引:4,自引:0,他引:4  
目的:探索低功率激光对细胞质膜通透性及细胞功能的影响。方法:以波长为632.8nm,功率密度为5.4mW/cm~2的氦氖激光照射人外周血淋巴细胞15、30、60分钟,并采用钙荧光指示剂Fura—2/Am定量测试法检测淋巴细胞内游离钙浓度和质膜Ca~(2+)—Mg~(2+)—ATP酶活性变化。结果:照射后淋巴细胞内游离钙浓度明显低于正常(P<0.05);同时细胞膜Ca~(2+)—Mg~(2+)—ATP酶活性增加(P<0.05);而且照射后细胞内游离钙浓度降低与质膜上Ca~(2+)—Mg~(2+)—ATP酶的激活呈负相关。结论:低功率激光照射激活细胞膜Ca~(2+)—Mg~(2+)—ATP酶活性,使细胞膜对钙通透性发生变化,且影响到细胞内Ca~(2+)贮存,造成细胞膜通透性和细胞功能的改变。  相似文献   

14.
本文对在等离子体刻蚀工艺中,功率、压强、气体比例重要参数对a-Si刻蚀均一性的影响进行了研究。采用PECVD成膜、RIE等离子体刻蚀,并通过台阶仪和光谱膜厚测定仪对膜厚进行表征。结果表明压强在10~15Pa,功率在5 500~6 500 W的参数区间,a-Si刻蚀均一性波动不大,适合工业化生产。a-Si刻蚀速率及刻蚀均一性对气体比例较为敏感,SF6∶HCl=800∶2 800mL/min时a-Si刻蚀均一性为最佳。四角排气方式对维持等离子体浓度作用明显,有利于刻蚀均一性的提升。四周排气方式会破坏等离子体浓度进而破坏a-Si刻蚀的均一性。  相似文献   

15.
Water channel aquaporin 5 (AQP5) is present in the apical membrane of the salivary gland acinar cells. We examined changes of AQP5-distribution during the fusion process of secretory granule membranes into the apical membrane and subsequent recovery process in the mouse parotid gland by administering isoproterenol (IPR) in vivo. We performed immunoperoxidase, immunofluorescence and immunoelectron microscopy. In the basal state, AQP5 was localized mainly in the apical membrane of the acinar cell. It was also present in the basolateral membrane to a lesser extent. When IPR was administered to mice, dot-like, vesicle-like and vacuole-like labeling for AQP5 was seen in the subapical regions by light microscopy. By immunoelectron microscopy, AQP5 was localized at both the apical and basolateral plasma membranes in the basal state. At 5 and 30 min after the IPR-administration, acinar lumen became enlarged and small invaginations formed by fusion of secretory granules were seen. AQP5 was positive along the apical plasma membrane and its small invaginations. At 60 min, large invaginations of the lumen were formed. AQP5 remained positive in the membrane of these large invaginations. At 6 h, large invaginations disappeared and AQP5 was localized in the apical plasma membrane. AQP5 was restricted to plasma membranes and continuous invaginations formed by the exocytosis of secretory granules. AQP5 was not detected in the cytoplasm. These observations show that AQP5 does not seem to be endocytosed during the membrane recycling process following the exocytosis.  相似文献   

16.
The in situ morphology change upon thermal annealing in bulk heterojunction blend films of regioregular poly(3‐hexylthiophene) (P3HT) and 1‐(3‐methoxycarbonyl)‐propyl‐1‐phenyl‐(6,6)C61 (PCBM) is measured by a grazing incidence X‐ray diffraction (GIXD) method using a synchrotron radiation source. The results show that the film morphology—including the size and population of P3HT crystallites—abruptly changes at 140 °C between 5 and 30 min and is then stable up to 120 min. This trend is almost in good agreement with the performance change of polymer solar cells fabricated under the same conditions. The certain morphology change after 5 min annealing at 140 °C is assigned to the on‐going thermal transition of P3HT molecules in the presence of PCBM transition. Field‐emission scanning electron microscopy measurements show that the crack‐like surface of blend films becomes smaller after a very short annealing time, but does not change further with increasing annealing time. These findings indicate that the stability of P3HT:PCBM solar cells cannot be secured by short‐time annealing owing to the unsettled morphology, even though the resulting efficiency is high.  相似文献   

17.
采用电感耦合等离子体(ICP)刻蚀系统,研究了氧等离子体表面处理对AlGaN/GaN HEMT欧姆接触电阻的影响。利用能量色散X射线光谱仪、光致发光谱和原子力显微镜以及电学测试设备对处理前后样品进行表征分析。结果表明,在最佳的氧等离子体处理条件(ICP功率250 W,射频功率60 W,压强0.8 Pa,氧气流量30 cm3/min,时间5 min)下,欧姆接触电阻为0.41Ω·mm,比参照样品接触电阻降低了约69%。分析认为经过氧等离子体处理后,在近表面处产生了一定数量的N空位缺陷,这些N空位表现为浅能级施主掺杂,有利于欧姆接触的形成。通过采用氧等离子体表面处理工艺制备的AlGaN/GaN HEMT,在+2 V的栅极偏压下获得了0.77 A/mm的最大漏极饱和电流。  相似文献   

18.
By adding a few percent of chlorine to oxygen plasma, the anodization rate of Si was enhanced; for example, the rate was doubled for oxygen containing 3-percent chlorine. With a chlorine concentration of 1.5 percent, the density of trap states at the Si-SiO2interface was reduced from 7×1011/cm2.eV to 5×1011/cm2.eV at the midgap of Si; after annealing at 800°C in argon for 60 min, it was reduced to 8 × 1010/cm2.eV, and did not return to the original value after heating the specimen to 800°C. The density and capture cross section of traps in plasma-anodic oxide were also measured using the constant-current avalanche-injection method. The number of electron traps with small cross sections in plasmaanodic SiO2films was reduced by annealing them at 800°C in argon, but SiO2films which were anodized in oxygen/chlorine plasma showed an increase of trap density under the same annealing condition.  相似文献   

19.
The feasibility of characterization of human blood fibrinogen levels using optical coherence tomography (OCT) was investigated. Three groups of blood samples were reconstituted of red blood cells: 1) phosphate-buffered saline; 2) plasma with its intrinsic fibrinogen removed and commercial fibrinogen added; and 3) native plasma with various fibrinogen levels (0-12?g/L). OCT signal slope (OCTSS) of blood was extracted from OCT depth-reflectivity profiles. Effects of hematocrit (HCT) and blood flow on OCTSS of the blood under various fibrinogen concentrations were also studied. The results of blood flowing at 5?mm/s showed that OCTSS of all the three groups at HCT of 40% decreases with the increasing fibrinogen concentration up to a certain level, i. e., >8, 6, and 4?g/L for groups 1, 2, and 3, respectively. The blood of group 2 at HCTs of 30%, 40%, and 50% had a rapid decrease in OCTSS in the range of fibrinogen concentration of 0-2, 0-6, and 0-10?g/L, respectively. OCTSS value of blood flowing at 2.5?mm/s was lower than that at 5?mm/s at each fibrinogen concentration. In conclusion, OCTSS has a strong correlation with plasma fibrinogen concentration, and has the potential to identify the abnormal level of human blood fibrinogen.  相似文献   

20.
By adding a few percent of chlorine to oxygen plasma, the anodization rate of Si was enhanced; for example, the rate was doubled for oxygen containing 3-percent chlorine. With a chlorine concentration of 1.5 percent, the density of trap states at the Si-SiO/sub 2/ interface was reduced from 7 X 10/sup 11//cm/sup 2//spl dot/eV to 5 X 10/sup 11//cm/sup 2/ /spl dot/eV at the midgap of Si; after annealing at 800/spl deg/C in argon for 60 min, it was reduced to 8 X 10/sup 10//cm/sup 2//spl dot/eV, and did not return to the original value after heating the specimen to 800/spl deg/C. The density and capture cross section of traps in plasma-anodic oxide were also measured using the constant-current avalanche-injection method. The number of electron traps with small cross sections in plasma-anodic SiO/sub 2/ films was reduced by annealing them at 800/spl deg/C in argon, but SiO/sub 2/ films which were anodized in oxygen/chlorine plasma showed an increase of trap density under the same annealing condition.  相似文献   

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