| 摘要 | 第3-5页 |
| Abstract | 第5-7页 |
| Chapter 1 Review | 第10-18页 |
| 1.1 Sources of Lead in the Environment | 第10-11页 |
| 1.2 Effects of lead on aquatic ecosystems | 第11-12页 |
| 1.3 Toxicity effects of lead | 第12-14页 |
| 1.3.1 Toxicity effects of lead on thyroid gland | 第12页 |
| 1.3.2 Toxicity effects of lead on skeletal system | 第12-14页 |
| 1.4 Characterization of oxidative stress and thyroid hormone-dependent genes | 第14-18页 |
| 1.4.1 Characterization of HSP, SOD and GPX | 第14-16页 |
| 1.4.2 Characterization of Dio2,Dio3, TRα and TRβ | 第16-18页 |
| Chapter 2 Toxicity of lead to Bufo gargarizans embryos:Chronic Effects onmalformation, oxidative stress and thyroid hormone-dependent genesexpression | 第18-34页 |
| 2.1 Introduction | 第18-20页 |
| 2.2 Material and methods | 第20-23页 |
| 2.2.1 Animals husbandry | 第20页 |
| 2.2.2 Water quality | 第20页 |
| 2.2.3 Determination of 96-h lethal concentration | 第20页 |
| 2.2.4 Chronic toxicity experiment for B. gargarizans embryos | 第20-21页 |
| 2.2.5 Scanning electron microscopy | 第21页 |
| 2.2.6 Reverse transcription into cDNA and qRT-PCR | 第21-23页 |
| 2.2.7 Statistical analysis | 第23页 |
| 2.3 Results | 第23-30页 |
| 2.3.1 Water quality | 第23页 |
| 2.3.2 Acute toxicity for the determination of 96 h LC50 | 第23-24页 |
| 2.3.3 Embryos malformation | 第24-26页 |
| 2.3.4 Effects of Pb on developmental stage, total length and weight of embryos | 第26-28页 |
| 2.3.5 Effect of Pb on SOD, GPX and HSP90 expression of B. gargarizans embryos atGs 22 | 第28-29页 |
| 2.3.6 Effects of Pb on Dio2, Dio3, TRα and TRβ expression in B.gargarizansembryos at Gs 22 | 第29-30页 |
| 2.4 Discussion | 第30-34页 |
| Chapter 3 Chronic toxicity of lead on larvae growth, development andmetamorphosis in Bufo gargarizans | 第34-58页 |
| 3.1 Introduction | 第34-35页 |
| 3.2 Materials and methods | 第35-38页 |
| 3.2.1 Embryo and tadpole maintenance | 第35-36页 |
| 3.2.2 Preparation of exposure solutions | 第36页 |
| 3.2.3 Sublethal toxicity test for B. gargarizans larvae | 第36页 |
| 3.2.4 Mortality, deformities, development and metamorphosis | 第36-37页 |
| 3.2.5 Histological measurements of thyroid gland | 第37页 |
| 3.2.6 Determination of the skeletal development | 第37-38页 |
| 3.2.7 Reverse transcription into cDNA and qRT-PCR | 第38页 |
| 3.2.8 Statistical analysis | 第38页 |
| 3.3 Results | 第38-53页 |
| 3.3.1 Mortality and malformation in B. gargarizans larvae | 第38-40页 |
| 3.3.2 Growth and general development | 第40页 |
| 3.3.3 Metamorphosis and size at metamorphic climax | 第40-42页 |
| 3.3.4 Effects of Pb on histopathological changes of thyroid | 第42-47页 |
| 3.3.5 Effect of Pb on bone formation | 第47-52页 |
| 3.3.6 Effect of Pb on expression of deiodinase and thyroid hormone receptor mRNAsin B. gargarizans larvae at Gs 42 | 第52-53页 |
| 3.4 Discussion | 第53-58页 |
| Chapter 4 Conclusion | 第58-60页 |
| References | 第60-76页 |
| 致谢 | 第76-78页 |
| 攻读硕士学位期间研究成果 | 第78页 |
