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1.
Polyploidization and centrosome hyperamplification in inflammatory bronchi   总被引:1,自引:0,他引:1  
OBJECTIVE AND DESIGN: Inflammatory and tumorous bronchi were screened in order to obtain new tumor relevant cytogenetic parameters. MATERIAL OR SUBJECTS: Bronchial cells of 32 patients were cultivated by standard cell culture procedures. METHODS: Tetraploidy and aneuploidy was determined by enumeration of chromosome 7 and 8 versus the number of centrosomes. The resulting data were correlated with histopathological data. RESULTS: Tetra- and aneuploidy of epithelial cells were detectable in 76% of tumor cell cultures, 75% of high grade inflammatory tissues and 40% of non- and low grade-inflammatory tissues. Additionally, we observed centrosome hyper-amplification and multipolar mitoses not only in the tumor but also in the early stages of inflammation. CONCLUSION: Inflammatory bronchi already show tumor-specific features and may consequently represent the preliminary genetic stage of cancer development in bronchi.  相似文献   
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M E Eichler  K M Rich 《Brain research》1989,482(2):340-346
The time course of dependence on nerve growth factor (NGF) for survival in sensory neurons in vitro was examined with microscopic and biochemical methods. Primary dorsal root ganglion (DRG) cultures from embryonic-day-15 (E-15) and day-19 (E-19) rats were maintained with standard dissociated cell culture techniques in the absence of most non-neuronal cells. After various times in culture, neurons were acutely deprived of neurotrophic support by changing to NGF-free medium and adding NGF antiserum to eliminate any residual NGF. Neuronal cultures were examined with phase microscopy; and, their metabolic activity was measured with a protein assay at various time points after NGF deprivation. E-15 neurons grown in culture for 5 days were exquisitely sensitive to acute NGF deprivation. By 12 h after NGF deprivation, neuronal morphology was severely disrupted and the majority of neurons appeared dead. E-15 neurons grown in culture for 8 or 11 days showed progressively less dependence on NGF for survival. These older neurons did not die until 24 and 48 h, respectively, following NGF withdrawal. Neurons grown in culture for 20 days did not show any morphologic changes by phase microscopy up to 4 days after NGF deprivation. Protein incorporation progressively decreased between 12 and 48 h after NGF withdrawal in E-15 neurons grown in culture for 5, 8, or 11 days.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Eosinophilic activation in cystic fibrosis.   总被引:1,自引:1,他引:0       下载免费PDF全文
D Y Koller  M Gtz  I Eichler    R Urbanek 《Thorax》1994,49(5):496-499
BACKGROUND--The neutrophil is a potent contributor to pulmonary destruction in cystic fibrosis. Since eosinophils also possess destructive potential the involvement of eosinophils in cystic fibrosis has been investigated. METHODS--Eosinophil numbers and levels of eosinophil cationic protein (ECP), a marker of eosinophil activation, were determined in the serum of 42 patients with cystic fibrosis and in the sputum of 10 of them. To determine neutrophil activation levels of myeloperoxidase (MPO) were also measured. RESULTS--In cystic fibrosis increased serum levels of ECP were detected compared with healthy non-atopic subjects. Serum ECP levels were not related to the peripheral blood eosinophil count. A strong correlation with ECP concentrations in sputum indicated that the level of ECP in serum was representative of its pulmonary level. Levels of MPO were also increased in cystic fibrosis. A strong correlation was found between MPO and pulmonary function. In addition, ECP was related to arterial oxygen and carbon dioxide tensions. Antibiotic treatment reduced neutrophil activation without effect on ECP levels. CONCLUSIONS--Until now Pseudomonas aeruginosa and neutrophils were held to be primarily responsible for progressive tissue damage in cystic fibrosis. The results of this study suggest that eosinophils might also participate in such pulmonary destruction.  相似文献   
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BACKGROUND: Developments in accelerator mass spectrometry (AMS) now permit the determination of femtogram amounts of 26Al in blood and in various tissues with good precision and free of external contamination. METHODS: In the present study we used trace quantities of 26Al to investigate the intestinal absorption and compartmentalization of aluminium in rats with renal failure (Nx, 5/6 nephrectomy) and in pair- fed controls (C). Single oral doses of 20 ng 26Al were administered to six animals in each group and, subsequently, 24-h post-load 26Al was analysed in serum, urine, bone, liver, and spleen by means of AMS. RESULTS: Serum concentrations of 26Al were significantly lower in uraemic rats compared to controls, whereas urinary excretion was comparable (Nx, 7.11 +/- 5.78 pg/day vs C, 9.46 +/- 6.10 pg/day), suggesting a higher fraction of ultrafiltrable serum 26Al in uraemia. The target tissues of cellular transferrin-mediated 26Al uptake, liver and spleen, tended to show a larger degree of aluminium accumulation in controls (0.26 +/- 0.31 pg/g vs Nx, 0.14 +/- 0.10 pg/g and 0.37 +/- 0.27 pg/g vs Nx, 0.25 +/- 0.27 pg/g respectively). In contrast, in bone, a site of extracellular aluminium deposition, 26Al concentrations were more elevated in uraemia (1.22 +/- 0.59 pg/g vs C: 0.68 +/- 0.30 pg/g). Estimated total 26Al accumulation in all measured target tissues was significantly higher in uraemic rats (28.15 +/- 9.90 pg vs C: 17.03 +/- 7.03 pg) and total recovery of 26Al from tissue and urine was 26.58 +/- 6.74 pg in controls and 35.75 +/- 7.03 pg in uraemic animals, suggesting a fractional absorption of 0.133% and 0.175% respectively. CONCLUSIONS: Our data suggest that fractional absorption from a dietary level dose of 26Al is about 0.13%. Compartmentalization occurs in transferrin-dependent target tissues such as liver and spleen; however, in quantitative terms extracellular deposition in bone is more important. Uraemia has a significant effect on the intestinal absorption and compartmentalization of aluminium. It enhances fractional absorption and increases subsequent extracellular deposition of aluminium in bone. However, at the same time uraemia does not increase transferrin-dependent cellular accumulation of aluminium in liver and spleen.   相似文献   
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Echographic follow-up examinations were performed in 72 patients in whom a choroidal melanoma was treated with (106Ru/106Rh) applicators. The observation period was between 6 and 15 months. Echographic measurement of tumor prominence and assessment of the degree of reflection proved to be important indicators for judging the success of beta radiation therapy. If the prominence diminishes and the degree of reflection increases after treatment, regression of the tumor may safely be assumed to have occurred. Apart from an increase in the prominence of the tumor, a constantly low or even falling level of reflection are signs of a less favorable prognosis.  相似文献   
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