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61.
Aihong Liu Kangning Sun Jiafeng Yang Dongmei Zhao 《Journal of nanoparticle research》2008,10(8):1303-1307
The aim of this study was to evaluate the lung toxicity of multi-wall carbon nanotubes (MWCNTs). The present work exposed
MWCNTs into the rats in intratracheal instillation administration modes. We systematically studied the distribution of nanoparticles
in vivo, target organs and time-effects of nanotoxicity, dose-effects of nanotoxicity, etc. These results indicate that under
the conditions of this test, pulmonary exposures to MWCNTs in rats by intratracheal instillation produced a series of multiple
lesions in a dose-dependent and time-dependent manner, evidence of a foreign tissue body reaction. 相似文献
62.
Elvira M. Gaspar Ana F. Lucena J. Duro da Costa H. Chaves das Neves 《Journal of chromatography. A》2009,1216(14):2749-2756
The gas chromatographic profiles of exhaled air from lung cancer patients have been investigated. The breath from healthy volunteers, smokers and non-smokers, and lung cancer patients without treatment and under radio and/or chemotherapy, was collected using Tedlar bags. Different profiles for healthy people and cancer patients could be recognized by multivariate analysis and significant diagnostic compounds could be established. Target compounds showed to be linear and branched hydrocarbons between C14 and C24. Solid phase microextraction (SPME) coupled to gas chromatography mass spectrometry GC–(TOF)-MS was used. The method showed good precision (RSD below 26%) and limit of detection ranged from 0.04 to 8.0 ppb. These findings show a high potential for establishment of laboratorial screening methods. Validation studies in a larger number of patients are being done. 相似文献
63.
Horng‐Jyh Harn Yi‐Lin Chen Po‐Cheng Lin Yeung‐Leung Cheng Shin‐Chun Lee Tzyy‐Wen Chiou Hsueh‐Hui Yang 《中国化学会会志》2010,57(2):180-188
To explore the potential tumor markers for lung adenocarcinoma, two‐dimensional gel electrophoresis (2DE) coupled with nano‐LC/MS/MS was used to analyze the differentially expressed proteins in 10 surgical resected lung adenocarcinoma tissues. 16 proteins were significantly different between the cancer tissue and adjacent normal tissue. Galectin‐1, peroxiredoxin II (Prx II), proapolipoprotein, glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), aldolase A, enolase 1, neuropolypeptide h3, Prx V, cyclophilin A, vimentin, protein disulfide isomerase (PDI), tropomyosin 3 (TPM 3), glutathione S‐transferase Pi (GST‐Pi), manganese superoxide dismutase (MnSOD), and cofilin 1 were up‐regulated in the cancer tissue. On the other hand, profilin was down‐regulated in the cancer tissue. Among these proteins, six proteins were validated by Western blot analysis. The identified proteins contributing to the spectrum of cancer progression may be used as potential diagnostic biomarkers for lung adenocarcinomas. 相似文献
64.
表面增强拉曼光谱已经展示了其在低浓度体液的检测方面的优势。对21例肺癌患者和22例正常人的唾液进行了检测和区分。肺癌患者在多处波数位的峰强较正常人有所下降,只有少数峰强度上升且幅度较小。这些峰主要归属为蛋白质和核酸,表明肺癌患者唾液中这些成分的含量较正常人为少。主成分分析法(PCA)和线性辨别分析(LDA)被用于两组数据的降维和区分,所得结果准确度为84%,灵敏度为94%,特异性为81%。 相似文献
65.
肺癌患者血清硒含量的测定及临床意义 总被引:1,自引:0,他引:1
测定40例肺癌患者的血清硒水平,并与健康对照组比较。结果表明,肺癌患者血清硒水平显著低于健康对照组,肺癌患者不同病期及病理类型间血清硒含量无统计学差异。揭示与其他很多肿瘤一样,肺癌患者血清硒水平显著降低,但不可作为判断病期及预测有无转移的指标。硒水平亦与病理类型无关。 相似文献
66.
Audio recordings were made while six vocally untrained individuals read sentences aloud after breathing to three different lung volume levels-typical, high, and low. A perceptual experiment was conducted on these speech samples. The perceptual experiment consisted of a two-alternative forced-choice design, in which listeners heard matched pairs of sentences and were asked to identify which sentence in the pair departed from normal sounding speech. The results of the perceptual experiment showed that listeners can accurately discriminate between speech produced at both lung volume extremes. The percentage of correct identification was higher for speech produced at low lung volumes than that for high lung volumes. Factors such as order of presentation and removal of SPL as an acoustic cue made little difference in the ability of listeners to discriminate lung volume level from the speech signals. 相似文献
67.
Analyses of exhaled air by means of electronic noses offer a large diagnostic potential. Such analyses are non-invasive; samples can also be easily obtained from severely ill patients and repeated within short intervals. Lung cancer is the most deadly malignant tumor worldwide, and monitoring of lung cancer progression is of great importance and may help to decide best therapy. In this report, twenty-two patients with diagnosed lung cancer and ten healthy volunteers were studied using breath samples collected several times at certain intervals and analysed by an electronic nose. The samples were divided into three sub-groups; group d for survivor less than one year, group s for survivor more than a year and group h for the healthy volunteers. Prediction models based on partial least square and artificial neural nets could not classify the collected groups d, s and h, but separated well group d from group h. Using artificial neural net, group d could be separated from group s. Excellent predictions and stable models of survival day for group d were obtained, both based on partial least square and artificial neural nets, with correlation coefficients 0.981 and 0.985, respectively. Finally, the importance of consecutive measurements was shown. 相似文献
68.
Branko Vukovi? Dario Faj Vanja Radoli? & Josip Planini? 《Isotopes in environmental and health studies》2013,49(2):169-176
Lung-cancer risk to the general population from indoor radon remains controversial, although studies of radon exposure have established that radon decay products have been a cause of lung cancer among miners. For the case group of patients, suffering from lung cancer, and the control group distributions of the number of homes with high indoor levels of radon were compared with the log-normal distribution, the empirical frequency distribution of the control group obeyed the theoretical log-normal distribution. Using the ratio of frequencies of the case group to the control groups, or the relative frequencies, an association between the relative frequencies and indoor radon concentrations was found, and a positive correlation coefficient was obtained, thus enabling the rate of lung cancer to be estimated for certain indoor radon concentrations. The significant difference between the mean radon levels for the case sample and the control led to the conclusion that patients with lung cancer lived in homes with radon concentrations which were significantly higher than those of Osijek’s inhabitants for the control sample. 相似文献
69.
Joseph S. Six Theodore Hughes-Riley David M.L. Lilburn Alan C. Dorkes Karl F. Stupic Dominick E. Shaw Peter G. Morris Ian P. Hall Galina E. Pavlovskaya Thomas Meersmann 《Magnetic resonance imaging》2014
Hyperpolarized 83Kr has previously been demonstrated to enable MRI contrast that is sensitive to the chemical composition of the surface in a porous model system. Methodological advances have lead to a substantial increase in the 83Kr hyperpolarization and the resulting signal intensity. Using the improved methodology for spin exchange optical pumping of isotopically enriched 83Kr, internal anatomical details of ex vivo rodent lung were resolved with hyperpolarized 83Kr MRI after krypton inhalation. Different 83Kr relaxation times were found between the main bronchi and the parenchymal regions in ex vivo rat lungs. The T1 weighted hyperpolarized 83Kr MRI provided a first demonstration of surface quadrupolar relaxation (SQUARE) pulmonary MRI contrast. 相似文献
70.
傅里叶变换红外光谱法研究肺组织切片 总被引:4,自引:1,他引:3
采用傅里叶变换红外光谱(FTIR)仪并借助OMNI采样器直接、快速地测定了正常肺组织及肺癌组织的红外光谱,通过研究表明,正常肺组织与肺癌组织样品的红外光谱在峰位、峰强及峰形等方面均存在明显而有规律的红外光谱差异,这反映了组织中的蛋白质、核酸和脂类等生物分子在不同性质的组织中含量上的差异。研究表明,FTIR可从分子水平上揭示正常肺组织和肺癌组织的特性,能对正常肺组织和肺癌组织的良、恶性的鉴别提供丰富而可靠的结构信息。 相似文献