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91.
用Nd:YAG倍频光532.0nm泵浦DCM染料输出的632.8nm激光作激发源,通过时间分辨法测得离体人肺腺癌,鳞癌及正常组织的特征峰荧光寿命分别为5.1,5.6和6.3ns实验结果表明:肿瘤组织的荧光寿命总小于正常组织的荧光寿命,这种方法将有可能用于精确诊断和定位肿瘤。  相似文献   
92.
The purpose of this study was to develop a simple and sensitive CE‐UV method to quantify erlotinib and metabolites in urine. Following liquid–liquid extraction, erlotinib, and metabolites were separated with a BGE whose composition was phosphate buffer (pH 2.5, 65 mM) with 0.5% Tween 20. The applied voltage was 22 kV, capillary temperature 25°C and the sample injection was performed in the hydrodynamic mode. All the analyses were carried out in a fused silica capillary with an internal diameter of 75 μm and a total length of 37 cm. The detection of target compounds was performed at 240 nm. The calibration was linear in the range 0.15–20 mg/L for erlotinib and metabolites. Inter‐and intraday imprecision were less than 4%. This simple, sensitive, accurate, and cost‐effective method can be used in routine clinical practice to monitor erlotinib concentrations in urine from nonsmall cell lung cancer patients.  相似文献   
93.
Pressurized CEC (pCEC) coupled with ESI‐QTOF‐MS using a sheathless interface was applied for metabolomics to develop an alternative analytical method for metabolic profiling of complex biofluid samples such as urine. The hyphenated system was investigated with mixed standards and pooled urine samples to evaluate its precision, repeatability, linearity, sensitivity, and selectivity. The applied voltage, mobile phase, and gradient elution were optimized and applied for the analysis of urinary metabolites. Multivariate data analysis was subsequently performed and used to distinguish lung cancer patients from healthy controls successfully. High separation efficiency has been achieved in pCEC due to the EOF. For metabolite identification, the pCEC‐MS separation mechnism was helpful for discriminating the fragment ions of glutamine conjugates from co‐eluted metabolites. Three glutamine conjugates, including phenylacetylglutamine, acylglutamine C8:1, and acylglutamine C6:1 were identified among 16 differential urinary metabolites of lung cancer. Receiver‐operating‐characteristic analysis of acylglutamine C8:1 resulted in an area‐under‐curve value of 0.882. Overall, this work suggests that this pCEC‐ESI‐QTOF‐MS method may provide a novel and useful platform for metabolomic studies due to its superior separation and identification.  相似文献   
94.
吕昕  王悦红  周建英 《应用数学》2015,37(2):117-119,123
目的 探讨甲状腺转录因子-1(TTF-1)、肺表面活性物质A(SPA)的表达与Ⅱ期肺腺癌患者术后复发及生存的相关 性。方法 收集经根治手术治疗的104 例Ⅱ期原发性肺腺癌患者资料,采用免疫组化法综合染色强度和阳性细胞所占比例进行半定量测定肿瘤组织的TTF-1、SPA 表达,分析两者与患者术后复发及生存的相关性。结果 TTF-1 阳性表达患者术后2 年复发率较阴性表达患者低[61.2%(60/98)vs 83.3%(5/6)],术后生存期较长[(26.00±1.89)个月vs(22.00±8.76)个月],但差异均无统计学意义(均P>0.05)。SPA 阳性表达患者术后2年复发率较阴性表达患者明显为低[54.8%(34/62)vs 79.2%(19/24)],术后生存期明显较长[(30.00±1.41)个月vs(21.00±2.18)个月],差异均有统计学意义(均P<0.05)。结论 SPA 阳性表达预示Ⅱ期原发性肺腺癌患者术后2年复发率低,生存期长。TTF-1 表达与Ⅱ期肺腺癌患者术后复发及生存有一定的相关性。  相似文献   
95.
刘开泰  陆妙珍  褚宇东 《应用数学》2015,37(4):283-286,294
目的 研究三叶因子1(TFF1)在肺癌组织及肺癌细胞株中的表达、甲基化状态及其功能。方法 选取98 例非小细胞肺癌患者手术切除的肺癌组织,采用RT-PCR、MSP 检测TFF1 在肺癌组织中的表达与甲基化状态,分析其与患者临床特点的相关性,以及检测肺癌细胞株H23、H1299、L78、H446、H157 及95D 中TFF1 的表达和甲基化状态以及5-aza-2''-deoxycytidine(DAC)处理后细胞株中TFF1 表达的变化。TFF1 转染H23 细胞株,MTT 法及克隆形成实验检测其增殖能力和克隆能力的变化,细胞凋亡实验及Western blot 检测凋亡相关蛋白Caspase3 表达水平。结果 TFF1 在肺癌组织中的甲基化率为56.1%(55/98)。TFF1 甲基化与肺癌患者的TNM 分期和淋巴结转移显著相关(P<0.001)。TFF1 在H23 和H157 中无表达,在H1299、H446 及95D 中表达较低,在L78 中表达较高。DAC 处理后,细胞株TFF1 表达的变化分别为表达恢复(H23、H157),表达增强(H1299,H446,95D)和无明显改变(L78)。恢复表达TFF1 后,H23 细胞株的增殖及克隆形成能力明显减弱(P<0.05),细胞凋亡率和凋亡相关蛋白Caspase3 活性片段的表达明显增加。结论 TFF1 在肺癌组织中的甲基化状态与肺癌的TNM 分期和转移密切相关。TFF1 在肺癌细胞中的表达受DNA 甲基化的调控。肺癌细胞株H23 中恢复表达TFF1 可以抑制其增殖和克隆能力,促进其凋亡。  相似文献   
96.
对165例慢性肺心病急性发作期患者和40例健康人的血清钾水平进行了分析,并比较了165例慢性肺心病急性发作期患者在不同血清钾水平下心律失常发生率。结果显示,慢性肺心病急性发作期患者血清钾水平低于健康人,P<0.01,具有显著差异;而在慢性肺心病急性发作期患者中,低钾血症者心律失常发生率高于清钾正常者,P<0.05,有显著差异。说明慢性肺心病急性发作期患者低钾血症多见,而血清钾降低增加慢性肺心病患者心律失常的发生。  相似文献   
97.
According to experience in voice therapy and singing pedagogy, breathing habits can be used to modify phonation, although this relationship has never been experimentally demonstrated. In the present investigation we examine if lung volume affects phonation. Twenty-four untrained subjects phonated at different pitches and degrees of vocal loudness at different lung volumes. Mean subglottal pressure was measured and voice source characteristics were analyzed by inverse filtering. The main results were that with decreasing lung volume, the closed quotient increased, while subglottal pressure, peak-to-peak flow amplitude, and glottal leakage tended to decrease. In addition, some estimates of the amount of the glottal adduction force component were examined. Possible explanations of the findings are discussed.  相似文献   
98.
王东  曹利平 《应用数学》2013,35(14):1322-1325
目的探讨肝癌术后发生肺部并发症的相关因素分析,以期为减少或避免术后肺部并发症的发生提供思路。方法选取行肝癌根治术的肝癌患者105例,其中22例(观察组)术后发生肺部并发症,83例(对照组)术后未发生肺部并发症。比较两组患者的一般资料(性别、年龄、吸烟指数、高血压病史、呼吸系统病史、糖尿病史、术前2周呼吸道感染史、肺部听诊情况)、术前检查结果(肿瘤位置、肿瘤大小、侵犯门静脉、侵犯肝静脉、门静脉癌栓、门静脉宽度、胆红素水平、白蛋白水平、凝血酶原时间、腹水、Child评分、Child分级、ALT、AST、GPT、AFP、血红蛋白水平、血小板、血氧饱和度、ASA分级)以及手术信息(手术切口、手术方式、手术时间、麻醉时间、术中输血量)。对上述比较差异有统计学意义的相关因素,采用非条件二元多因素Logistic回归分析其与肝癌术后肺部并发症的相关性。结果单因素分析显示:低蛋白血症、手术时间、麻醉时间及术中输血量是肝癌术后发生肺部并发症(胸腔积液、肺炎)的危险因素(P<0.05或0.01)。多因素Logistic回归分析结果显示术前白蛋白水平是发生术后肺部并发症的独立危险因素(P<0.05)。结论术前白蛋白水平是肝癌术后肺部并发症的独立危险因素。  相似文献   
99.
N-ortho, meta and para-(ferrocenyl)benzoyl dipeptide esters 2-10 were prepared by coupling ferrocenyl benzoic acids 1(ortho, meta and para) to the dipeptide ethyl esters GlyAbu(OEt) 2-4, GlyNva(OEt) 5-7 and GlyNle(OEt) 8-10 in the presence of N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride and 1-hydroxybenzotriazole. The compounds were fully characterized by a range of NMR spectroscopic techniques, mass spectrometry and cyclic voltammetry. The cytotoxicity of 3, 6 and 9 versus H1299 lung cancer cells were 10.5 μM, 19.1 μM and 18.9 μM, respectively, whereas N-{meta-(ferrocenyl)-benzoyl}-glycine-l-alanine ethyl ester 11 and N-{para-(ferrocenyl)-benzoyl}-glycine-l-alanine ethyl ester 12 gave IC50 values of 4.0 and 6.6 μM, respectively. Therefore, an increase in alkyl chain length of the second amino acid also increases the IC50 values. Cell cycle analysis of N-{ortho-(ferrocenyl)-benzoyl}-glycine-l-alanine ethyl ester 13 suggests a block in the G2/M phase of the cell cycle.  相似文献   
100.
Molecular interaction forces, operative in microscopic foam films obtained from the isolated hydrophobic fractions of porcine lung surfactant (AS-B) are investigated by monitoring film thickness h as a function of electrolyte concentration (C el) and direct measurements of disjoining pressure/thickness (Π(h)) isotherms. The steep decrease of the common film thickness with the increase of C el evidences the action of long-range electrostatic surface forces. The experimental h(C el) curve indicates that non-Derjaguin-Landau-Verwey-Overbeek (DLVO) repulsive forces are operative at C el where common black (CBF) and Newton black films (NBF) are obtained including the physiologically relevant C el=0.14 mol dm−3 NaCl. The action of additional non-DLVO forces is corroborated by the comparison of the experimentally measured Π(h) isotherm with the DLVO theory. Considering the presence of proteins in AS-B and the formation of lipid-protein complexes it is inferred that steric type forces are operative in CBF and NBF.  相似文献   
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