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991.
Marc Bonnard Ig‐Chun Eom Jean‐Louis Morel Paule Vasseur 《Environmental and molecular mutagenesis》2009,50(1):60-67
Polluted soil sampled from a former coking plant in Lorraine (France) was studied for its genotoxicity and reproductive effects on the Eisenia fetida earthworm. Genotoxicity was investigated by means of the single‐cell gel electrophoresis (comet) assay on the coelomocytes of earthworms after 4 and 10 days of exposure to the soil. DNA damage and a decline in the number of coelomocytes extruded from earthworms were observed at coking plant soil concentrations of 20 and 40% (w/w) in ISO soil. These soil concentrations had previously been shown to significantly reduce cocoon and juvenile productions after 28 and 56 days of earthworm exposure, respectively. The results showed that genotoxic pollutants in the tested soil were still bioavailable despite the age of the contaminated soil. Similar values of the no‐observed‐effect concentration (NOEC) corresponding to 10% of the contaminated soil and of the lowest soil concentration tested inducing effects (LOEC) corresponding to 20% of the contaminated soil were obtained from reproductive and genotoxicity endpoints. Among the soil pollutants measured, polycyclic aromatic hydrocarbons (PAHs) appeared to be the most likely source of the genotoxicity recorded, although effects of metals could not be excluded. Measurement of genotoxicity in earthworms could complement the existing standardized tests used in the ecotoxicological assessment of the risk associated with contaminated soils. Environ. Mol. Mutagen., 2009. © 2008 Wiley‐Liss, Inc. 相似文献
992.
Anthony E. Archibong Frank Inyang Aramandla Ramesh Michael Greenwood Tultul Nayyar Prapaporn Kopsombut Darryl B. Hood Alfred M. Nyanda 《Reproductive toxicology (Elmsford, N.Y.)》2002,16(6)
The objective of this study was to evaluate the effect of subacute exposure to inhaled benzo(a)pyrene (BaP) on fetal survival and luteal maintenance using timed-pregnant Fisher 344 rats. Prior to assignment of pregnant rats to treatment and control groups, numbers of implantation sites were determined on gestation day (GD) 8 via midventral laparotomy. Subsequently, animals were assigned randomly to three treatment groups and two control groups. Treatment consisted of subacute exposure of rats via inhalation to BaP 25, 75, and 100 μg/m3, 4 h daily for 10 days (GD-11–20). Control animals were either sham exposed to carbon black (CB) to control for inert BaP carrier or remained unexposed (UNC). Blood samples were collected on days 15 and 17 of gestation via sinus orbital veini-puncture for plasma. Number of pups per litter was determined postpartum and fetal survival rate was expressed as a percentage of the corresponding implantation sites. Radioimmunoassays were used to determine plasma progesterone, estrogen, and prolactin (indirect measurement of decidual luteotropin) concentrations. Fetal survival among BaP-treated rats declined in a dose-dependent manner (25 μg/m3, 78.3% per litter; 75 μg/m3, 38.0% per litter; 100 μg/m3, 33.8% per litter; P<0.05) compared with CB (96.7% per litter) and UNC (98.9% per litter). Plasma progesterone, estrogen, and prolactin concentrations also declined as a result of subacute exposure of rats to BaP compared to controls. These data suggest that inhaled BaP compromised fetal survival and consequently luteotropic activity in the exposed animals. 相似文献
993.
994.
复方卡托普利片的药代动力学及生物等效性评价 总被引:1,自引:0,他引:1
目的:研究两种复方卡托普利片的药代动力学及生物等效性。方法:采用柱前衍生化高效液相色谱法测定10名志愿受试者单剂量口服50mg两种复方卡托普利片后血中卡托普利血药浓度的变化情况,数据经 3p87药代动力学程序处理结果:两种片剂药时曲线下面积分别是(864.30±169.99)(ng/mL)×h与(853.38±165.77)(ng/mL)×h,达峰时间分别为(0.91 ±0.27)h与(0.91 ±0.26)h,峰浓度分别是(285.00±37.36)ng/mL与(279.80± 32.77)ng/mL结论:配对t检验与双单侧t检验结果表明:二者药时曲线下面积、峰浓度及达峰时间均无显著性差异(P>0.05),为生物等效制剂。 相似文献
995.
996.
中药口腔溃疡复合膜为一中药新剂型,由药膜与覆盖膜构成。对不同配方和材料的成膜性,粘附性及释药性的比较表明,以PVA17-88-CMCNa(1:1)为药膜基质,PVA17-88为覆盖膜材料较为理想。 相似文献
997.
本文观察了高血压病(EH)患者的红细胞钠离子转运和血浆内源性类洋地黄物质(EDLC)的变化及硝苯啶和哌唑嗪对其影响,结果:EH患者红细胞的钠泵功能和Na~+-K~+内向协同转运明显低于正常,血浆EDLC显著升高,但其与钠泵非平行改变。经降压治疗,EH患者的钠泵和EDLC明显改善。本文对钠离子转运与EH的关系,及降压药物对其作用作了初步探讨。 相似文献
998.
用自制的水杨醛肟和邻羟基苄胺,设计合成了生物营养素-水杨醛缩邻羟基苄胺合二氧化钼类配合物,并对其组成和结构进行了测定与分析。 相似文献
999.
P. Brust R. Bauer B. Walter R. Bergmann F. FÜchtner G. Vorwieger J. Steinbach B. Johannsen U. Zwiener 《International journal of developmental neuroscience》1998,16(5):2063
Available information on the dopamine (DA) metabolism of the immature brain is rare. In order to establish a useful animal model we have performed PET experiments in anesthetized neonatal pigs using 6-[[18]F]-fluoro-L-DOPA (FDOPA) as tracer. In this study, we have simultaneously determined the cerebral blood flow and the rate constant of FDOPA conversion by the aromatic amino acid decarboxylase, the ultimate enzyme in the synthesis of dopamine. The estimated values of FDOPA decarboxylation in the basal ganglia were similar to values calculated in adult animals and humans. However, in contrast to those studies a significant decarboxylation was also found in the frontal cortex and the cerebellum. HPLC analysis of brain samples also revealed extensive and rapid metabolism of FDOPA in the five investigated brain regions. At 8 min after tracer injection about 80% of FDOPA was already converted to FDA and its metabolites. Surprisingly, a rather high fraction (16fn221%) of [[18]F]-fluoro-3-methoxytyramine was found which may indicate a low storage capacity of vesicular DA at this perinatal stage. It is suggested that the findings are related to the ontogenetic development of the dopaminergic system. The knowledge of the regulation of the DA metabolism in the immature brain may have implications for the understanding of neurodevelopmental effects of perinatal oxygen deprivation. 相似文献
1000.
C. H. Marvin L. Allan B. E. McCarry D. W. Bryant 《Environmental and molecular mutagenesis》1993,22(2):61-70
Highly contaminated sediment from the Hamilton Harbour area of western Lake Ontario was examined using a bioassay-directed fractionation methodology. A sediment sample was extracted using a Soxhlet apparatus and the resulting extract was fractionated into compound classes using an alumina clean-up step and high performance liquid chromatographic techniques. The resulting fractions were subjected to bioassays using TA98- and TA100-like strains modified by the inclusion of genes for the activating enzymes nitroreductase and O-acetyl-transferase. The majority of the mutagenic activity displayed by the sample extract was found to be present in the fraction containing the polycyclic aromatic hydrocarbons (PAH). Extracts of the PAH-containing fraction displayed dramatically higher responses with the TA100 type strains with metabolic activation. Further separation of the PAH-containing fraction showed the majority of the biological activity coeluted with PAH having molecular masses of 276, 278, and 302 amu. © 1993 Wiley-Liss, Inc. 相似文献