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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
4.
Ittel TH; Steinhausen C; Kislinger G; Kinzel S; Nolte E; Sieberth HG 《Nephrology, dialysis, transplantation》1997,12(7):1369-1375
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
5.
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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Zusammenfassung Aus mitteleuropäischen Singvögeln werden die folgenden neuen Menacanthus-Arten beschrieben: M. festivus nov. spec. von Fringilla coelebs, M. pius nov. spec. von Turdus merula, M. polonicus nov. spec. von Turdus pilaris, M. vistulanus nov. spec. von Sylvia borin und M. wipszyckii nov. spec. von Chloris chloris. Die Tatsache, daß das insgesamt aus mehreren Funden und besonders für M. pius nov. spec. aus zahlreichen Exemplaren bestehende, dieser Arbeit zugrunde liegende Untersuchungsmaterial fast ausschließlich Weibchen enthält, wird als Ausgangspunkt für eine Diskussion des Speziesbegriffs bei uniparentalen Mallophagenarten herangezogen. Zur Klärung dieser auch evolutionstheoretisch bemerkenswerten Problematik wird ein Forschungsprogramm für Menacanthus-Arten entwickelt.Mit 10 Textabbildungen 相似文献
8.
Interchromosomal duplications of the adrenoleukodystrophy locus: a phenomenon of pericentromeric plasticity 总被引:13,自引:5,他引:13
Eichler EE; Budarf ML; Rocchi M; Deaven LL; Doggett NA; Baldini A; Nelson DL; Mohrenweiser HW 《Human molecular genetics》1997,6(7):991-1002
A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD)
locus of the X chromosome has duplicated to specific locations near the
pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11.
Comparative sequence analysis reveals 92-96% nucleotide identity,
indicating that the autosomal ALD paralogs arose relatively recently during
the course of higher primate evolution (5-10 million years ago). Analysis
of sequences flanking the duplication region identifies the presence of an
unusual GCTTTTTGC repeat which may be a sequence-specific integration site
for the process of pericentromeric- directed transposition. The breakpoint
sequence and phylogenetic analysis predict a two-step transposition model,
in which a duplication from Xq28 to pericentromeric 2p11 occurred once,
followed by a rapid distribution of a larger duplicon cassette among the
pericentromeric regions. In addition to facilitating more effective
mutation detection among ALD patients, these findings provide further
insight into the molecular basis underlying a pericentromeric-directed
mechanism for non- homologous interchromosomal exchange.
相似文献
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