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21.
石油烃污染对海胆胚胎及浮游幼虫生长发育的影响 总被引:2,自引:0,他引:2
为研究石油烃污染对海胆的毒性, 采用海胆胚胎发育技术, 观察0号柴油、船用轻质柴油和船用重质燃料油分散液对马粪海胆胚胎及浮游幼虫生长发育的影响.结果显示, 三种油品分散液使得胚胎发育至2-细胞期、4-细胞期、8-细胞期、16-细胞期、囊胚期的时间延后,这种延后的现象随着发育进程和油品分散液浓度升高而愈发明显.与对照组相比,染毒的海胆浮游幼虫生长速度明显减慢,二腕幼虫及四腕幼虫的体长均变短.三种油品对于海胆胚胎生长发育过程的毒性顺序为:0号柴油>船用轻质柴油>船用重质燃料油. 相似文献
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Dr M. Bergere J. Selva M. Baud M. Volante B. Martin J. N. Hugues F. Olivennes R. Frydman M. Auroux 《黑龙江环境通报》1995,15(9):835-841
We performed fluorescence in situ hybridization (FISH) with a chromosome 18-specific probe on human abnormal cleaved embryos, fertilized either by two spermatozoa and exhibiting three pronuclei (3 PN) or normally fertilized and exhibiting two pronuclei (2 PN) with subsequent severe fragmentation and/or blocking. The aim of the study was to evaluate the incidence of chromosome 18 anomalies among these embryos, in order to evaluate the FISH efficiency on such material and to obtain more precise and complete data than those obtained with classical cytogenetic analysis. For the 3 PN cleaved embryos, FISH confirmed the frequent regulation towards diploidy (25 per cent) and the high frequency of mosaics (53 per cent). For the 2 PN blocked or damaged embryos, FISH permitted chromosome evaluation, which was otherwise impossible with classical cytogenetic techniques: we also found a high mosaic frequency (45 per cent) with these embryos. If this frequency were the same for normally developing embryos, it would be a major obstacle to the reliability of either chromosomal or genetic preimplantation diagnosis. 相似文献
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本研究以模式生物斑马鱼(Danio rerio)为对象,观察在不同浓度Cd Se/Zn S量子点(Cd Se/Zn S QDs)暴露下,斑马鱼胚胎形态发育、氧化应激以及金属硫蛋白MT基因和应激蛋白Hsp70基因表达变化情况.结果表明,Cd Se/Zn S QDs对斑马鱼胚胎72 hpf(hours post fertilization)的半致畸效应浓度(EC50)为316.994 nmol·L-1.QDs暴露影响了斑马鱼胚胎的死亡率、畸形率、孵化率、自主运动频率和体长,以及引起胚胎卵凝集,心包囊肿,脊椎弯曲等多种毒性效应;同时导致斑马鱼体内超氧化物歧化酶(SOD)活性变化以及丙二醛(MDA)含量增加.QDs还诱导斑马鱼MT基因和Hsp70基因表达上调,斑马鱼机体产生一系列自我保护反应来减轻QDs所造成的伤害.这表明:Cd Se/Zn S QDs对斑马鱼胚胎产生了毒性效应,其毒性可能与其核心Cd2+的释放、粒径大小以及氧化应激有关. 相似文献
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High concentrations of metals (cadmium, copper, lead, and zinc) and of lindane were measured in the sediment and in the spawn and tadpoles of Bufo bufo, Rana dalmatina, and Rana ridibunda from two Austrian locations. Residues in spawn suggest maternal transfer. Increase of the metal concentrations from spawn to advanced tadpole stage is explained by the larval microphaguous feeding habits which cause high exposition of the tadpoles to substances concentrating in sediments and suspended particles. Metal and pesticide concentrations in spawn and tadpoles are toxic to various other aquatic organisms and are furthermore considered to be potentially hazardous to the anurans themselves. The results are conform with world‐wide observations of contamination of anuran larvae with heavy metals, and prove the significance of non‐point source chemical exposure due to allochthonous toxicant input by wind load and precipitation. 相似文献
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采用静态法,在实验室控制条件下,观察处理前后的城市污水对斑马鱼胚胎的毒性效应,并探讨其对斑马鱼胚胎可能的毒性机理。结果表明,兰州市安宁区M污水处理厂处理前的污水、处理后接触池出水和接触池出水入黄河排污口水对胚胎均有较高的毒性,其72 h EC50在21.384%~108.492%之间;对处理胚胎孵化成的仔鱼毒性也很明显。上述几种污水均降低斑马鱼胚胎的孵化率,增加胚胎及其孵化仔鱼的畸形。 相似文献
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2,3,7,8-四氯二苯并对二恶英(2,3,7,8-Tetrachlorodibenzo-p-Dioxin,TCDD)是一种持久性环境有机污染物质,它在有机体内的蓄积性引起研究人员的重视。以青鳉胚胎作为实验动物模型,使用原位杂交和定量聚合酶链锁反应(Polymerase Chain Reaction,PCR)技术从分子水平探讨了TCDD对胚胎耳泡的发育及其毒性作用机制。结果表明,TCDD造成青鳉幼鱼耳泡生成障碍。通过原位杂交和q PCR分析表明,TCDD引起软骨发育的变化与SOX9b表达降低有密切的关联。研究认为青鳉胚胎是一种非常敏感的TCDD模式动物,其耳泡软骨发育以及SOX9b基因表达可能是一种二恶英发育毒性的效应标记物。 相似文献
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Sjaan Koppel Amanda N. Stephens Kristie L. Young Phuong Hua Richard Chambers Craig Hassed 《Traffic injury prevention》2018,19(5):480-487
Objectives: This study investigated the relationship between self-reported aberrant driving behaviors, mindfulness, and self-reported crashes and infringements.Methods: Three hundred and eighteen participants (M = 46.0 years, SD = 13.7 years; female: 81.8%) completed an online survey that assessed aberrant driving behaviors, mindfulness (including regular mindfulness meditation [MM]), and self-reported crashes and infringements during the past 2 years. Structural equation modeling (SEM) was used to examine the relationship between self-reported aberrant driving behaviors and mindfulness simultaneously, as well as with participants' age and estimated kilometers driven over the past year.Results: The results of the SEM showed that mindfulness was negatively related to each self-reported aberrant driving behavior, with the strongest relationships being between mindfulness and driving-related lapses (?0.58) and errors (?0.46). Participants who practice MM had significantly fewer crashes in the past 2 years and reported significantly fewer driving-related violations and lapses compared to participants who did not practice MM (crashes: 9.3% vs. 18.8%, P < .05; violations: M = 6.66 [SD = 3.44] vs. M = 7.68 [SD = 4.53], P < .05; errors: M = 5.17 [SD = 3.44] vs. M = 6.19 [SD = 4.12], P < .05).Conclusions: More research is needed to understand whether MM results in more mindful and attentive drivers or whether individuals who practice MM may have other traits or behaviors that are linked to improved safety. 相似文献
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采用斑马鱼胚胎毒性测试方法,研究了PFOA/PFOS对斑马鱼的急性毒性和生命早期阶段生长发育的影响.结果表明,PFOS/PFOA对斑马鱼有明显毒性作用,LC50(48 h)分别为1 005 mg/L和107 mg/L,LC50(96 h)分别为499 mg/L和71 mg/L.PFOS/PFOA抑制斑马鱼胚胎发育,可导致胚胎发育畸形,甚至死亡,高浓度(>240 mg/L)PFOS损伤细胞膜,导致胚胎分裂中的细胞发生自溶而卵凝结死亡,抑制胚胎原肠胚的形成.在各种亚致死效应中,脊柱畸形对PFOS暴露最敏感,其EC50=9.14 mg/L,PFOA暴露最敏感亚致死性毒理学终点为96 h孵化,对应EC50=328.0 mg/L.PFOA/PFOS导致胚胎发育延迟,具有发育毒性. 相似文献
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In Patagonia, enhanced levels of ultraviolet radiation (UVR) are affecting not only the southernmost territories but the northern as well, and there is a growing body of evidence indicating effects on terrestrial and aquatic communities. Anurans occur along a wide geographical gradient in Patagonia and are common in shallow waters, usually breeding during spring when seasonal UV-B radiation is at its highest level. In this paper we analyse the effective irradiances (I) experienced in nature by eggs and embryos of the patagonian anurans Pleurodema bufoninum, Pleurodema thaul and Bufo spinulosus papillosus, considering water and egg jelly optical properties. Besides, we determine photoprotective pigments in eggs and embryos of the different species, and ontogenetic shifts in pigment concentration. Finally, we studied the effects of natural and enhanced levels of UV-B on eggs of P. bufoninum aiming to evaluate the role of the jelly envelope in screening the damaging radiation. The evidence gathered in this work shows that natural and enhanced UV-B levels did not induce significant changes on the survivorship but incremented the occurrence of malformations. Also, the species experiencing high levels of exposure presented high concentrations of melanin suggesting that exposure to sunlight triggers photoprotection by pigments. Collectively our results suggest that the studied species bear certain levels of adaptation to cope with high ambient UVR conferred by environmental and biological factors. 相似文献