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排序方式: 共有5595条查询结果,搜索用时 15 毫秒
41.
Ibrahim Chahoud Ralf Krowke Gerd Bochert Brigitte Bürkle Diether Neubert 《Archives of toxicology》1991,65(1):27-31
Possible effects on the next generation after long-term exposure (subcutaneous administration) of male rats to very high doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were studied. Two dose regimes were applied: TCDD-25 (initial dose: 25 g/kg body wt; maintenance dose: 5 g/kg body wt, once weekly) and TCDD-75 (initial dose: 75 g/kg body wt; maintenance dose: 15 g/kg body wt). Male rats were treated for 10 weeks before mating and then throughout the entire 12 week mating period. They were mated to unexposed virgin females. One group of pregnant females was used for teratological evaluations, and another group was allowed to deliver. No significant differences were observed in the number of implantations or fetuses per litter, and resorption rate, and fetal weight between the controls and TCDD-treated groups. No gross-structural anomalies occurred in any of the fetuses sired by TCDD-treated males. In the TCDD-25 group an increased frequency of two types of variations was observed which also occur in controls: incompletely ossified fingers (TCDD-25=5.1%, controls=2.6%), and incompletely ossified ossa zygomatica (TCDD-25=1.8%, controls=0.5%). In the TCDD-25 group a slight but statistically significant increase was observed in the rate of stillbirths (TCDD-25=1.3%, controls=0.1%), apparently due to an unusually low frequency occurring in the controls (overall historical controls=0.6%). There was no difference in postnatal mortality (TCDD-25=1.3%, controls=1.3%). Taken together, despite the very high doses of TCDD used, the data do not provide evidence for biologically significant paternally-mediated developmental toxicity in the fetuses and newborn. 相似文献
42.
Kluger's Fixateur Interne proved to be an excellent tool not only in spinal trauma for repositioning of impacted fractures and transpedicular stabilization of the dorsal column but also in other forms of thoracic or lumbar instability.After spinal tumor excision from a dorsal approach and vertebral replacement with methylmethacrylate additional stability through dorsal fixation was achieved with this device.Spondylodiscitis, symptomatic spondylolisthesis, spinal instability from degenerative disc disease as well as nonunion following previous surgery could be cured using Kluger's internal fixation. Rare complications, i.e. from broken screws or rods (5%) caused no problems, but some patients required a second operation for readjustment of malpositioned screws which were causing pain or neurological deficit. 相似文献
43.
Petra Heinm?ller Christof Gross Kurt Beyser Claudia Schmidtgen Gerd Maass Michele Pedrocchi Josef Rüschoff 《Clinical cancer research》2003,9(14):5238-5243
PURPOSE: For the first time a large number (563) of non-small cell lung cancer (NSCLC) samples was used to compare three different technologies for the assessment of HER2 status. Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) were used for tumor tissue samples, and ELISA for serum samples. The results were compared with other tumor entities, mainly breast. EXPERIMENTAL DESIGN: Samples (563) from patients suffering from primary advanced or metastatic NSCLC were evaluated. RESULTS: HER2 overexpression was demonstrated using IHC in 20% (83 of 410) of the specimens, whereas 2% (7 of 378) were positive by FISH and 6% (31 of 511) showed elevated serum HER2 levels (>15 ng/ml) by ELISA. Sixty-six specimens were positive by IHC only and 13 by ELISA only, whereas none of the specimens was positive only by FISH. Concordance between all of the techniques was seen for only 3 specimens. Of 7 IHC 3+ specimens, 4 showed gene amplification by FISH, and 3 were positive by ELISA (>15 ng/ml), whereas of 76 IHC 2+ cases only 2 were amplified by FISH, and 4 were positive by ELISA. HER2 positivity by at least one of the three techniques was most common in adenocarcinomas, at 29% (42 of 143). CONCLUSION: Gene amplification and HER2 protein overexpression at the 3+ level appear to be uncommon in NSCLC. The concordance between FISH and IHC 3+ disease was good in this study, in addition, ELISA would have detected several patients without IHC/FISH-positive disease. 相似文献
44.
45.
The T393C polymorphism of the G alpha s gene (GNAS1) is a novel prognostic marker in bladder cancer. 总被引:2,自引:0,他引:2
Ulrich H Frey Andreas Eisenhardt Gerd Lümmen Herbert Rübben Karl-Heinz J?ckel Kurt W Schmid Winfried Siffert 《Cancer epidemiology, biomarkers & prevention》2005,14(4):871-877
The G protein G(alpha)s pathway is linked to proapoptotic signaling in cancer cell lines. To assess the role of the GNAS1 locus encoding G(alpha)s as a genetic factor for disease progression of transitional cell carcinoma (TCC) of the bladder, we genotyped the synonymous T393C polymorphism in 254 patients with TCC (minor allele frequency: 0.43) to examine a potential association between genotypes and disease progression. Using Kaplan-Meier estimates to calculate 5-year probabilities of follow-up, we could show that progression-free survival, metastasis-free survival, and cancer-specific survival was significantly increased in TT genotypes (56%, 84%, 82%) compared with CC genotypes (35%, 53%, 58%). In multivariate Cox proportional hazard analysis, the T393C polymorphism was an independent prognostic factor for clinical outcome. Homozygous CC patients were at highest risk for progression [odds ratio (OR), 1.94; P = 0.020], metastasis (OR, 3.49; P = 0.005), and tumor-related death (OR, 2.49; P = 0.031) compared with TT genotypes. Heterozygous patients had an intermediate risk compatible with a gene-dose effect. Real-time PCR analysis of urothelial tumor tissue as well as adipose and heart tissue revealed that G(alpha)s mRNA expression was highest in TT genotypes, indicating a proapoptotic effect in these genotypes. In conclusion, the GNAS1 T393C status associated with differential G(alpha)s mRNA expression is a novel independent prognostic marker for clinical outcome supporting a functional role of G(alpha)s in bladder cancer progression. 相似文献
46.
Cancer-testis genes are coordinately expressed and are markers of poor outcome in non-small cell lung cancer. 总被引:5,自引:0,他引:5
Ali O Gure Ramon Chua Barbara Williamson Mithat Gonen Cathy A Ferrera Sacha Gnjatic Gerd Ritter Andrew J G Simpson Yao-T Chen Lloyd J Old Nasser K Altorki 《Clinical cancer research》2005,11(22):8055-8062
PURPOSE: Cancer-testis genes mapping to the X chromosome have common expression patterns and show similar responses to modulators of epigenetic mechanisms. We asked whether cancer-testis gene expression occurred coordinately, and whether it correlated with variables of disease and clinical outcome of non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Tumors from 523 NSCLC patients undergoing surgery were evaluated for the expression of nine cancer-testis genes (NY-ESO-1, LAGE-1, MAGE-A1, MAGE-A3, MAGE-A4, MAGE-A10, CT7/MAGE-C1, SSX2, and SSX4) by semiquantitative PCR. Clinical data available for 447 patients were used to correlate cancer-testis expression to variables of disease and clinical outcome. RESULTS: At least one cancer-testis gene was expressed by 90% of squamous carcinoma, 62% of bronchioloalveolar cancer, and 67% of adenocarcinoma samples. Statistically significant coexpression was observed for 34 of the 36 possible cancer-testis combinations. Cancer-testis gene expression, either cumulatively or individually, showed significant associations with male sex, smoking history, advanced tumor, nodal and pathologic stages, pleural invasion, and the absence of ground glass opacity. Cox regression analysis revealed the expression of NY-ESO-1 and MAGE-A3 as markers of poor prognosis, independent of confounding variables for adenocarcinoma of the lung. CONCLUSIONS: Cancer-testis genes are coordinately expressed in NSCLC, and their expression is associated with advanced disease and poor outcome. 相似文献
47.
Wobst I Schiffmann S Birod K Maier TJ Schmidt R Angioni C Geisslinger G Grösch S 《Biochemical pharmacology》2008,76(1):62-69
Dimethylcelecoxib (DMC), a derivative of celecoxib, has been developed to distinguish between the COX-dependent and COX-independent anti-carcinogenic effects of celecoxib. Although DMC has been shown to have no COX-inhibitory activity, it is important to ensure that DMC has no other influence on prostaglandin production. Interestingly, in this study we show that DMC inhibits PGE(2) production in vitro in the low micromolar range in different cancer cell lines. This effect can be at least partly explained by our findings that DMC inhibits microsomal prostaglandin E synthase-1 (mPGES-1) activity in a cell-free assay. Moreover, it prevents mPGES-1 up-regulation after stimulation of HeLa cells with IL-1beta and TNFalpha. Conversely, DMC has no effect on the expression levels of COX-1, COX-2, cytosolic PGES (cPGES) or mPGES-2 in these cells. However, in the cell-free assay DMC inhibits mPGES-1 to a maximum of 65% only and concentrations needed for inhibition of mPGES-1 activity are about 10-fold higher than needed for inhibition of PGE(2) production in cell culture. This suggests that DMC also has an impact on other proteins involved in PGE(2) production. In cell culture experiments the anti-proliferative effect of DMC, measured by the WST-1 assay, seems not to be dependent on PGE(2) inhibition, as DMC was equally effective in unstimulated HeLa cells as well as in stimulated HeLa cells, and the addition of external PGE(2) did not reverse the anti-proliferative effect of DMC in HCA-7 cells. We conclude that DMC is not a suitable non-prostaglandin-inhibiting control substance for research purposes. 相似文献
48.
Gerd Habelmann 《Journal of molecular medicine (Berlin, Germany)》1940,19(47):1211-1214
Ohne Zusammenfassung 相似文献
49.
Elbel Nippe Dubitscher Beil Mueller B. Peters Gerd Notz-Schwarz I. v. Krber Gerstenberg Hebestreit Steiger Estler Bergerhoff Lochtkemper Graf Romberg Whrer Kanitz Sjvall Einar Klauer Wachholz L. 《International journal of legal medicine》1940,33(4):311-319
International Journal of Legal Medicine - 相似文献
50.