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排序方式: 共有1671条查询结果,搜索用时 15 毫秒
1.
D. Lothschütz M. Jennewein S. Pahl H.F. Lausberg A. Eichler W. Mutschler R.G. Hanselmann M. Oberringer 《Inflammation research》2002,51(8):416-422
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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Death of sensory ganglion neurons after acute withdrawal of nerve growth factor in dissociated cell cultures 总被引:1,自引:0,他引:1
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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Wolfdieteich Eichler 《Parasitology research》1940,12(1):94-94
Ohne Zusammenfassung 相似文献
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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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Wolfdietrich Eichler 《Parasitology research》1939,11(2-3):205-214
Ohne Zusammenfassung 相似文献
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Many different strategies are used to recruit students into scientific research careers, including neuroscience research. These strategies are rarely based on knowledge about students; instead, activities are selected based on their ease of implementation. The goal of the LEARN Project is to encourage high school students into mental health science research using the theme of learning and memory. One intervention the authors developed is five Web-based biographies introducing students to contemporary neuroscientist role models studying learning and memory. To guide the design of this intervention, the authors created a survey to determine where students obtain career information and who and what influences their career selection. In a convenience sample of 124 students, the authors found that almost all students use the Internet for information about careers, in addition to consulting family members and teachers. Students' career selections are influenced most by family members, teachers, and people already in the field. The most important factors students look for in their future career are money, fun, and a good match between current interests and future careers. The data affirm the value of outreach efforts that go beyond students to include a broader audience of parents and teachers who play a critical role in career selection. 相似文献
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C Eichler A Hertel P K Lommatzsch P Fuhrmann 《Klinische Monatsbl?tter für Augenheilkunde》1987,190(1):17-20
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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