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81.
AIM: To detect the membrane surface morphology of cancer cells treated with artesunate (ART) under atomic force microscope (AFM). METHODS: Human gastric cancer SGC-7901 cells were cultured and treated with different concentrations of ART for 24 h. The membrane surface morphology, three-dimensional structures and ultrastructural changes of SGC-7901 cells were observed under AFM. The apoptosis of SGC-7901 cells was detected by flow cytometry. RESULTS: The AFM images revealed that the cell nuclear area was full and the surface of cell membrane was flat and smooth in control group. Compared with control group, the cell nuclear area collapsed and suffered atrophy, and the membrane surface had more pores in ART treatment groups. More pores were observed and the diameter of the pores was increased with the increase in ART concentration. The cell membrane ultrastructure showed that the particles in control group had an intensive distribution, some were cord-shaped and some gathered into a mass. The particles in ART treatment groups were fewer and distributed sparsely. Moreover, there were obvious lacunae in the surface of cell membrane. Quantitive measurement found that the height of cell nucleus area was decreased, and the surface root mean square roughness (Rq) and the surface average roughness (Ra) became smaller in ART treatment groups compared with control group. The apoptotic rates of the cells in ART treatment groups were increased with the increase in ART concentration, and were all significantly higher than that in control group. CONCLUSION: Our findings emphasize the significance of AFM in exploring the changes of the membrane surface morphology at nano-scale resolution following the treatment with anticancer drugs, which could not only identify the specific characteristics of morphological changes of the tumor cells, but also provide micromorphological references to reveal the mechanisms of anticancer drugs. 相似文献
82.
极细链格孢激活蛋白对大豆光合特性、叶绿素荧光参数及产量的影响 总被引:1,自引:0,他引:1
为探讨激活蛋白对大豆生长、产量的影响,以大豆冀豆17为研究对象,利用光合仪与称重法测量了不同浓度极细链格孢激活蛋白(1,2,3,4,5,6μg/m L)处理后大豆的光合特性、叶绿素荧光参数及产量。结果表明,随着施用的极细链格孢激活蛋白浓度的增加,大豆叶绿素含量、净光合速率、气孔导度、蒸腾速率、最大光化学量子效率(Fv/Fm)、有效量子效率(ΦPSⅡ)和光化学猝灭系数(q P)呈先上升后下降的趋势。施用1,2,3,4μg/m L浓度的极细链格孢激活蛋白不仅提高了大豆叶绿素含量,而且增加了大豆叶片的净光合速率、气孔导度、蒸腾速率,同时还能提高叶绿素荧光的最大光化学量子效率(Fv/Fm)、有效量子效率(ΦPSⅡ)和光化学猝灭系数(q P)。其中以3,4μg/m L浓度的处理效果最好。施用更高浓度的激活蛋白(5,6μg/m L),上述光合特性与叶绿素荧光促进效果下降或者消失。施用中浓度激活蛋白(3,4μg/m L)大豆产量增加了11.21%~14.76%。结果表明,喷洒合适浓度的极细链格孢激活蛋白是一种促进大豆增产的有效措施。 相似文献
83.
土壤肥力对高产小麦品种烟农1212旗叶叶绿素荧光特性和产量的影响 总被引:1,自引:0,他引:1
为了解土壤肥力对小麦旗叶叶绿素荧光特性和籽粒产量的影响,以高产小麦品种烟农1212为材料,比较分析了常年小麦产量水平为12 000和9 000kg·hm-2的高低两种土壤肥力条件下麦田土壤贮水消耗量、小麦旗叶叶绿素含量、叶绿素荧光参数、叶面积指数和籽粒灌浆速率的差异。结果表明:(1)高肥力下小麦全生育期60~100cm土层土壤贮水消耗量显著高于低肥力。(2)相对于低土壤肥力,高土壤肥力显著增加了小麦旗叶开花后21~35d的叶绿素相对含量和实际光化学效率(ΦPSⅡ)、开花后28d和35d的最大潜在光化学效率(Fv/Fm)、光化学猝灭系数(qp)以及开花后14~35d相对电子传递速率(ETR)。高土壤肥力下小麦在孕穗期、开花期、开花后21~35d具有较高的叶面积指数。(3)高土壤肥力可显著提高灌浆中后期的籽粒灌浆速率,显著增加籽粒产量及其构成因素、水分利用效率和氮肥偏生产力。由此可见,高土壤肥力能够改善小麦光合能力,有利于产量形成,进而提高产量和促进水肥高效利用。 相似文献
84.
[目的]建立一种检测8-羟基喹啉铜的方法.[方法]采用自制合成的吖啶酮衍生物10-甲基-3-硝基-吖啶酮(MAT)作为增强型荧光信号探针,建立8-羟基喹啉铜的测定方法.[结果]在最佳条件下荧光增强值与8-羟基喹啉铜的浓度在5×10-9 ~5 ×10-5 mol/L范围内成良好的线性关系,检测限为6×10-10 mol/L.[结论]该方法灵敏度高、检测范围宽,结果令人满意,可用于实际样品中8-羟基喹啉铜含量的直接测定. 相似文献
85.
LI Quan-feng WANG Xiao-ming ZHU Shi-jun AI Jing GAO Huan-huan XU Chang-qing 《园艺学报》2001,17(7):690-691
AIM:To examine the effect of compound salvae-dropping-pill (CSDP) on intracellular free calcium in cultured rat myocardial cells subjected to hypoxia and reoxygenation.METHODS:The Fluo- 3/AM was applied to probe intracellular calcium concentration and the fluorescent intensity was detected using laser confocal microscopy technique.RESULTS:Fluorescent intensity in hypoxia plus CSDP group was significantly lower (1 217.78±312.07) than that of hypoxia group (1 509±508.48), and the Fluorescent intensity of hypoxia/reoxygenation plus CSDP group was also markedly lower (1 567.91±577.61) than that of hypoxia/reoxygenation group (1 617.60±477.53).CONCLUSION:The cultured rat myocardial cells could be effectively protected by administration of CSDP in case of hypoxia and reoxygenation through decreasing the intracellular calcium concentration. 相似文献
86.
Association of Helicobacter with cholangiohepatitis in cats 总被引:1,自引:0,他引:1
Greiter-Wilke A Scanziani E Soldati S McDonough SP McDonough PL Center SA Rishniw M Simpson KW 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(4):822-827
Infection with Helicobacter spp. is increasingly linked with hepatobiliary inflammation and neoplasia in people and in a variety of animals. We sought to determine if Helicobacter species infection is associated with cholangiohepatitis in cats. Deoxyribonucleic acid was extracted from tissue blocks from cats with cholangiohepatitis (32), noninflammatory liver disease (13), and cats with normal liver histology (4). Deoxyribonucleic acid was polymerase chain reaction-amplified with 2 sets of Helicobacter genus-specific primers, gel purified, and sequenced. Polymerase chain reaction-positive hepatic tissue was further examined with Steiner's stain, immunocytochemistry for Helicobacter species, and eubacterial fluorescent in situ hybridization. Gastric tissues of cats with known Helicobacter infection status served as controls for deoxyribonucleic acid extraction and sequence comparison. Helicobacter species were detected in 2/32 cats with cholangiohepatitis, and 1/17 controls. Sequences had 100% identity with Helicobacter species liver, Helicobacter pylori, and Helicobacter fenelliae/cinaedii in a cat with suppurative cholangitis, Helicobacter species liver, Helicobacter pylori, and Helicobacter nemistrineae in a cat with mild lymphocytic portal hepatitis, and Helicobacter bilis in a cat with portosystemic vascular anomaly. In contrast, sequences from gastric biopsies showed highest homology (99-100%) to "Helicobacter heilmannii," Helicobacter bizzozeronii, Helicobacter felis, and Helicobacter salomonis. Fluorescent in situ hybridization revealed a semicurved bacterium, with Helicobacter-like morphology, in an intrahepatic bile duct of the cat with suppurative cholangitis. This study has identified Helicobacter deoxyribonucleic acid in 2/32 cats with cholangiohepatitis and 1/13 cats with noninflammatory liver disease. Deoxyribonucleic acid sequences of hepatic Helicobacter species were distinct from those found in the stomach and are broadly consistent with those identified in cat intestine and bile, and hepatobiliary disease in people and rodents. 相似文献
87.
[目的]为研究毛竹光能转化过程中荧光特性。[方法]利用IMAGING-PAM对生长良好的毛竹叶片进行荧光成像反应试验,分别进行荧光成像、诱导以及快速光曲线的研究。[结果]毛竹各荧光参数存在着大小不一的异质性,除PSII最大量子产量(Fv/Fm)、叶片吸光系数(Abs)外其他参数均存在较大的异质性。异质性以相对电子传递速率(rETR)最大,其次是PSII实际量子产量(Y)、光化学淬灭(qP)、非光化学淬灭(NPQ)、Abs、Fv/Fm。毛竹叶片叶脉NPQ明显高于叶肉部分,而叶脉qP则明显低于叶肉部分。从荧光诱导曲线可以看出,Y、qP、NPQ和rETR均很低,此后均逐渐达到稳态。其中,Y、rETR、qP均为一直升高并达到稳态,NPQ则有一个先升高再降低逐步达到稳态的过程。Fv/Fm处于0.8以下,这说明该植株可能处于亚健康状态,受到某种因子的胁迫。从快速光曲线的测定可以看出,毛竹半饱和光强(Ik)为148,初始斜率(α)为0.215 541,最大潜在相对电子传递速率(rETRmax)为31.9。[结论]该研究能够为毛竹高产栽培、高效利用提供基础支撑。 相似文献
88.
89.
Obiective:Observing the expression changes of serum proteome in model rats after intervention of the Granules of Eliminating Phlegm and Removing Blood Stasis (豁痰祛瘀颗粒 also known as GEPRB),screenin... 相似文献
90.
[目的]建立贝类折光马尔太虫荧光定量PCR检测方法。[方法]根据基因库中折光马尔太虫的基因保守序列,设计合成了一对引物和一条TaqMan探针,建立检测折光马尔太虫的荧光定量PCR方法,将建立的荧光定量PCR检测方法与常规PCR检测对比。[结果]所建立的荧光定量PCR方法灵敏度可达40个拷贝/μl,比常规PCR灵敏度高100倍,对派琴虫、单孢子虫、嗜水气单胞菌、荧光假单胞菌、副溶血弧菌、溶藻弧菌、河弧菌和拟态弧菌等病原体的检测结果为阴性。[结论]研究建立的折光马尔太虫荧光定量PCR方法具有特异、敏感、快速、定量、重复性好等优点,可用于临床上折光马尔太虫感染的检测。 相似文献