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41.
Franz Kronecker 《Naunyn-Schmiedeberg's archives of pharmacology》1883,16(5-6):344-360
Ohne Zusammenfassung 相似文献
42.
Dr. Franz Hofmeister 《Naunyn-Schmiedeberg's archives of pharmacology》1883,16(5-6):393-439
Ohne Zusammenfassung 相似文献
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Metabolic activation to a mutagen of 3-hydroxy-trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene, a secondary metabolite of benzo[a]pyrene 总被引:2,自引:0,他引:2
Glatt Hansruedi; Seidel Albrecht; Ribeiro Odartey; Kirkby Charles; Hirom Paul; Oesch Franz 《Carcinogenesis》1987,8(11):1621-1627
3-Hydroxy-trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (3-OH-BP-7,8-diol)wag isolated from arylsulfatase/ß-glucuronidase-treatedbile of rats to which 3-hydroxybenzo[a]pyrene (3-OH-BP) hasbeen administered. This triol was investigated for mutagenicityin Salmonella typhimurium (reversion to histidine prototrophyof strains TA 97, TA 98, TA 100 and TA 1537) and in V79 Chinesehamster cells (acquisition of resistance to 6-thioguanine).When no exogenous metabolizing system was added the triol wasinactive, while 3-OH-BP showed weak mutagenic effects with allfour bacterial strains. In the presence of NADPH-fortified postmitochondrialsupernatant fraction (S9 mix) of liver homogenate from Aroclor1254-treated rats, the mutagenicity of 3-OH-BP was potentiated,and the triol was activated to a mutagen(s). In the presenceof S9 mix, the triol was 518 times more mutagenic than3-OH-BP in strains TA 97, TA 100 and TA 1537, but both compoundsshowed similar mutagenic potencies with strain TA 98. Thesestrain differences strongly suggest that the mutagenicity of3-OH-BP in the S9 mix-mediated test was not exclusively dueto metabolites of 3-OH-BP-7, 8-diol. Trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene(BP-7,8-diol), like the triol, showed mutagenic effects onlyin the presence of S9 mix. Strain TA 1537 was reverted by thetriol but not by the diol. In the other bacterial strains thediol was more mutagenic than the triol, the difference in potencybeing largest in strain TA 100 (2.5-to 10-fold, depending onthe experimental conditions). In V79 cells, the diol was a potentmutagen, while the triol showed only very weak mutagenic effects.However the triol was more cytotoxic than the diol. High cytotoxicityof the triol was observed even in the absence of S9 mix. Theresults of the present study demonstrate that metabolites of3-OH-BP-7, 8-diol) are biologically-active derivatives of benzo[a]pyrene.Comparison of the mutagenic effectiveness in different bacterialstrains also reveals that metabolites of 3-OH-BP-7, 8-diol andof BP-7, 8-diol substantially differ in the kind of geneticalterations they evoke. 相似文献
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The bis-pyridinium dioxime HLö 7 is considered to possess promising therapeutic properties in the treatment of organophosphate poisoning. Acute circulatory and respiratory effects of HLö 7 and HI 6 were therefore compared in anaesthetized guinea-pigs. Female Pirbright white guinea-pigs were anaesthetized with urethane and the carotid artery, jugular vein and trachea were cannulated. Saline or atropine, 10 mg/kg, or HLö 7 or HI 6 (30 or 100 μmol/kg, each) or atropine plus oxime were injected intravenously after base line measurements. Respiratory and circulatory parameters were recorded for 60 min., then blood was drawn for AChE measurement. Injection of HLö 7 or HI 6 alone resulted in a temporary, dose-dependent hypotension, an almost unchanged heart rate and a slight respiratory stimulation. A more severe hypotension appeared after the administration of atropine plus HLö 7 or HI 6. In these groups heart rate and respiration were markedly stimulated. Measurement of AChE activity in blood samples revealed no impairment by HLö 7 or HI 6 with or without atropine. These results suggest that HLö 7 has only transient effects on the cardiorespiratory system after intravenous administration and its safety regarding acute circulatory and respiratory toxicity is comparable to HI 6. 相似文献
48.
[目的]探讨聚乙烯颗粒对人单核细胞分泌促炎因子与抗炎因子的影响.[方法]用Ceridust 3615 颗粒(聚乙烯颗粒)(平均直径14.27,6.39,1.74,1.01,0.54和0.28 μm)分别刺激人单核细胞,颗粒体积与细胞数的比例为100:1和10:1.在颗粒刺激细胞24 h后,运用ELISA检测培养上清液中的促炎因子(白介素-1β,白介素-6和细胞坏死因子α)及抗炎因子(白介素-10)的表达.[结果]Ceridust 3615 颗粒可刺激单核细胞分泌白介素-1β(IL-1β)、白介素-6(IL-6)和细胞坏死因子α(TNFα),但未能引起白介素-10(IL-10)的表达.颗粒比例增高可促使单核细胞分泌更多的IL-6和TNFα,却减少IL-1β分泌,对IL-10的分泌则无影响.个体差异使巨噬细胞对同种颗粒的刺激产生不同的反应,其差异可达到30倍.[结论]个体差异是影响人工关节寿命的重要因素,聚乙烯颗粒可刺激单核细胞产生炎因子但对产生抗炎因子(IL-10)的作用不明显,提示促炎因子与抗炎因子的不平衡或许是人工关节松动不断进展的另一重要因素. 相似文献
49.
Early detection of prosthetic-hip loosening. Comparison of low- and high-viscosity bone cement 总被引:1,自引:0,他引:1
In 1987, we reported the 1-year migration of the prosthetic components in 16 hips followed by roentgen stereophotogrammetry after fixation with either low- or high-viscosity cement. We now report the migration of these prosthetic components during another 2 postoperative years. Eight acetabular components, four in each group, migrated cranially; and four femoral components, three in the low-viscosity and one in the high-viscosity group, migrated distally. All but two migrations were obvious 4 months postoperatively, which indicates that what is called late loosening is the result of late detection rather than of late occurrence of loosening. Low-viscosity cement did not provide improved prosthetic fixation. 相似文献
50.