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61.
62.
对黄姜种质资源、化学成分及组织培养研究概况进行了综述.为下一步开展相关研究提供依据.  相似文献   
63.
The levels and distributions of polybrominated diphenyl ethers (PBDEs) in chicken tissues from an electronic waste (e-waste) recycling area in southeast China were investigated. Human dietary intake by local residents via chicken muscle and eggs was estimated. The mean PBDEs concentrations in tissues ranged from 15.2 to 3138.1 ng/g lipid weight (lw) and in egg the concentration was 563.5 ng/g lw. The results showed that the level of total PBDEs (PPBDEs) in the chicken tissue was 2–3 orders of magnitude higher than those reported in the literature. The large di erence of PPBDEs concentrations between tissues confirmed that the distribution of PBDEs in tissues depend on tissue-specificity rather than the “lipid-compartment”. BDE-209 was the predominant congener (82.5%– 94.7% of PPBDEs) in all chicken tissues except in brain (34.7% of PPBDEs), which indicated that deca-BDE (the major commercial PBDE formulation comprising 65%–70% of total production) was major pollution source in this area and could be bioaccumulated in terrestrial animals. The dietary PBDEs intake of the local residents from chicken muscle and egg, assuming only local bred chickens and eggs were consumed, ranged from 2.2 to 22.5 ng/(day kg body weight (bw)) with a mean value of 13.5 ng/(day kg bw), which was one order of magnitude higher than the value reported in previous studies for consumption of all foodstu s.  相似文献   
64.
Some fish‐kills in Basque rivers were studied by gill tissue analysis: Samples were wet digested and the solution was analyzed by atomic absorption spectroscopy. In three cases, the cause was linked to the effluents of an aluminium anodizing factory, cyanide caused one kill and copper wastes were related with another. Three cases were attributed to natural reasons and one of the kills was of unknown origin.  相似文献   
65.
Heavy metals pollution in aquatic environments is a major problem contributing to human health issues. The study of these pollutants through bioindicators such as the oyster Crassostrea iredalei is important for (1) determining the levels and sources and (2) regulating the quantity of pollutants. The concentrations of cadmium (Cd), manganese (Mn), copper (Cu), zinc (Zn), and lead (Pb) in tissues of C. iredalei, sediment and surrounding water was measured, and data was analyzed to determine the relationship between sampling periods and between oyster tissue, sediment, and water. The highest concentration of metals in oyster tissue was Zn, followed by Cu, Mn, Cd, and Pb. Concentrations of Cd, Cu, and Zn exceeded the maximum level allowed according to the Malaysian Food Act of 1983, which is equivalent to the WHO recommended levels of heavy metals in organisms used for consumption. The highest metal concentration in sediment was Mn followed by Zn, Pb, Cu, and Cd. Concentrations of heavy metals in surrounding water were Zn, Pb, Cu, Mn, and Cd. There was no correlation between metal concentration in oyster tissue and in sediment for all five metals.  相似文献   
66.
Effects of synthetic pyrethroid insecticide α-cypermethrin were investigated following intradermal dose (5–50 mM) of cypermethrin to male albino Wistar rats. Glucose, protein, cholesterol, triglycerides, urea, uric acid, creatinine, hemoglobin, blood RBC, and WBC content were determined 6 h after pesticide administration. Biochemical parameters and blood cell count changed significantly in treated rats at all doses. Low-dose cypermethrin affected early biochemical changes in rats.  相似文献   
67.
采用Western blot和实时荧光定量RT-PCR方法,研究不同强度不同时间冷刺激后大鼠心脏、大脑、睾丸和肺脏中冷诱导RNA结合蛋白(CIRP)的表达情况.结果表明:常温(20℃±1℃)下大鼠4种组织中均存在一定的CIRP的表达;急性冷刺激组(-10℃±1℃、-4℃±1℃、0℃±1℃、4℃±1℃)心脏、大脑和睾丸中CIRP mRNA表达在冷刺激0~6 h呈上升趋势,6 h时达到最高值,随后呈下降趋势,肺脏中CIRP mRNA表达在0~6 h呈下降趋势,在6 h时达到最低值,随后呈上升趋势;慢性冷应激组(10℃±1℃)大鼠心脏、大脑和睾丸3种组织中CIRP mRNA在不同时间点(1周、2周、3 W周)的表达均高于正常对照组(P>0.05),肺脏CIRP mRNA表达均低于对照组(P>0.05),并且同一组织不同时间点之间差异不显著(P>0.05).可见冷刺激后CIRP的表达存在一定规律并且表现出组织特异性,可能与组织保护特异性有关.  相似文献   
68.
通过研究发育期大鼠脑单胺类神经递质质量比及单胺氧化酶活性,探讨环境暴露水平的六溴环十二烷对发育期大鼠的神经毒性作用。选择10μg/kg、50μg/kg、100μg/kg、300μg/kg的剂量对新生3 d大鼠进行暴露,饲养42 d后断头取脑组织,测定多巴胺(DA)、去甲肾上腺素(NE)、5-羟色胺(5-HT)的质量比及单胺氧化酶(MAO)的活性。结果表明,在10~100μg/kg的暴露剂量范围,DA质量比随暴露剂量的升高而下降,NE质量比呈现上升趋势,5-HT质量比则极显著性升高(p<0.01);与此同时,MAO的活性随剂量增加而升高,在100μg/kg剂量出现显著性升高(p<0.05)。而300μg/kg的剂量作为较高暴露水平的参照,只对DA产生显著性影响(p<0.05)。DA、5-HT、NE的质量比及MAO活性的变化可能在大鼠的中枢神经系统的发育障碍中发挥了重要作用,并且环境暴露水平的HBCD对发育期大鼠脑具有低剂量高效应的毒性反应特征。  相似文献   
69.
70.
以斑马鱼(Danio rerio)为受试鱼种,研究了磷石膏浸出液对水生生物的急性毒性及亚致死浓度下对斑马鱼肝脏、肌肉和鳃中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GPx)和丙二醛(MDA)的影响,以及96 h后肝脏和鳃组织病理变化.结果表明,磷石膏浸出液中总磷、氟化物和Cd、Cr、Pb、Hg浓度超出地表水V类水标准,其对斑马鱼的毒性较强,96 h半数致死浓度(LC50)为6.5%(体积分数).慢性毒性实验显示,随暴露时间延长,各组织内3种抗氧化酶活性变化趋势不完全一致,但高浓度(0.65%和3.25%)暴露后期(72 h和96 h)几乎均受到显著抑制,其中,SOD对浸出液的敏感性最高;MDA含量变化规律较为一致,随浸出液浓度增加而升高,肝脏、肌肉和鳃中MDA最高含量均出现在72 h,分别是空白对照组的1.8、1.6和2.1倍,至96 h时略有降低,但仍显著高于对照组.各浓度组暴露96 h后,肝细胞窦间隙扩大,肝巨噬细胞增多,细胞核固缩,部分细胞质空泡化,组织水肿;鳃组织出现上皮细胞增生、脱落,鳃丝充血,鳃小片弯曲变形等现象.综上,未加处理的磷石膏浸出液已超出斑马鱼耐受极限,任其排入环境具有潜在的生态风险.  相似文献   
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