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221.
研究针对采自上海孙桥农业园区8个不同来源的农田表层土壤样品(旱田、水田、大棚中的不同作物土壤),以辛基酚聚氧乙烯醚(OPEOn)为唯一碳源培养,在好氧条件下,观察其生物降解情况,并初步分离得到了六株OPEOn降解菌株(1个真菌,5个细菌),它们能够不同程度地降解OPEOn,利用气相色谱仪(GC)对降解产物进行了表征和鉴别,分别从3个土壤样品中分离得到的菌株对OPEOn降解得最为彻底,为后续研究工作的深入奠定了生物学基础。  相似文献   
222.
17α-甲基睾酮是一种人工合成雄激素,在水产养殖以及医药行业中广泛使用,其对鱼类的内分泌干扰效应研究工作相对较少.通过甲基睾酮对稀有鲫幼鱼的42天流水暴露,观察了其性腺发育和生物标记物变化.在500ng·L-1甲基睾酮暴露组中幼鱼生长受到抑制(p≤0.05),在50ng·L-1以上暴露组中性腺指数显著增加(p≤0.05),雄性个体比率明显升高.通过组织学观察发现,50ng·L-1以上浓度甲基睾酮暴露后卵巢组织切片中出现了精子细胞,且精子细胞数量随剂量的增加而增加.通过生物标记物卵黄蛋白原测定发现,在50ng·L-1以上浓度甲基睾酮暴露后,稀有鲫幼鱼血清中的卵黄蛋白原水平显著增加(p≤0.05).综合分析,17α-甲基睾酮主要表现出雄激素效应,而其在稀有鲫体内的代谢物则能够应激卵黄蛋白原,对稀有鲫幼鱼的最低可观察效应浓度(LOEC)为50ng·L-1.因此,仅依靠体内卵黄蛋白原应激单项指标不能准确判定化学品是否是环境类雌激素.  相似文献   
223.
Whether general environmental exposures to endocrine disrupting chemicals (including pesticides and dioxin) might induce decreased sex ratios (male/female ratio at birth) is discussed. To address this issue, the authors looked for a space-time clustering test which could detect local areas of significantly low risk, assuming a Bernoulli distribution. As a matter of fact, if the endocrine disruptor hypothesis holds true, and if the sex ratio is a sentinel health event indicative of new reproductive hazards ascribed to environmental factors, then in a given region, either a cluster of low male/female ratio among newborn babies would be expected in the vicinity of polluting municipal solid waste incinerators (MSWIs) (supporting the dioxin hypothesis), or local clusters would be expected in some rural areas where large amounts of pesticides are sprayed. Among cluster detection tests, the spatial scan statistic has been widely used in various applications to scan for areas with high rates, and rarely (if ever) with low rates. Therefore, the goal of this paper was to check the properties of the scan statistics under a given scenario (Bernoulli distribution, search for clusters with low rates) and to assess its added value in addressing the sex ratio issue. This study took place in the Franche-Comté region (France), mainly rural, comprising three main MSWIs, among which only one had high dioxin emissions level in the past. The study population consisted of 192,490 boys and 182,588 girls born during the 1975–1999 period. On the whole, the authors conclude that: (i) spatial and space-time scan statistics provide attractive features to address the sex ratio issue; (ii) sex ratio is not markedly affected across space and does not provide a reliable screening measure for detecting reproductive hazards ascribed to environmental factors.  相似文献   
224.
This study investigated the concentrations of Tributyltin (TBT) in water, sediment, and fish muscle samples taken from Kaohsiung Harbor and Kaoping River estuary, Taiwan. TBT concentrations in water and sediment samples ranged from less than 18.5 to 34.1 ng Sn L?1 and from 2.44 to 29.7 ng Sn g?1 weight per weight (w/w), respectively. Concentrations in the TBT‐contaminated fish muscle samples ranged from 10.8 to 79.6 ng Sn g?1 w/w. The TBT concentrations in fish muscle were higher than those in water and sediment samples. The fish muscle/water TBT bioconcentration factor (BCF) ranged from 590 to 3363 L kg?1. Additionally, the water samples were assessed for androgenic activity with an MCF7‐AR1 human breast cancer cell line. The androgenic activity ranged from 0.94 to 3.1 ng‐dihydrotestosterone per litre water (ng‐DHT L?1). Higher concentrations of TBT in water and sediment samples occurred in the dry season, but the androgenic activity had higher values in the rainy season.  相似文献   
225.
Endocrine disrupting compounds (EDCs), pharmaceuticals and personal care products (PPCPs) have attracted much attention due to widespread contamination in aquatic environment. In this study, we determined 13 EDCs and PPCPs in fish blood, bile and muscle by using gas chromatography-mass spectrometry (GC-MS). The limits of quantitation (LOQ) were in the ranges of 0.23–2.54, 0.22–2.36 ng·mL−1, and 0.24–2.57 ng·g−1 dry weight (dw) for fish blood, bile and muscle, respectively. Recoveries of target compounds spiked into sample matrices and passed through the entire analytical procedure ranged from 65% to 95%, from 60% to 92% and from 62% to 91% for blood, bile and muscle, respectively. The methods were applied to the analysis of fish from a lake in California. Target compounds were relatively low in bile, and only bisphenol A (BPA) and diclofenac were measurable near the LOQ. Seven of 13 compounds were detected in blood, with total concentrations up to 39 ng·mL−1. Only BPA was frequently found in muscle, with mean concentration of 7.26 ng·g−1 dw. The estimated daily intake of BPA through fish consumption for U.S. resident was significantly lower than the tolerable daily intake recommended by the European Food Safety Authority. This study showed that the exposure to the bisphenol A from fish diet is unlikely to pose a health risk.  相似文献   
226.
《环境化学》2012,31(6)
甲状腺激素在脊椎动物新陈代谢、生长发育与繁殖等生理过程中起着重要的调节作用.环境污染物种类和数量不断增加,其中有很多污染物具有环境内分泌干扰的作用.甲状腺对环境污染物具有极敏感的反应,污染物不仅会引起滤泡及滤泡细胞大小、滤泡细胞数量和滤泡腔中胶质含量的改变,影响到甲状腺激素合成、分泌、转运以及代谢中多种酶的表达和活性变化,还参与和甲状腺激素的竞争性结合,进而影响到机体中由甲状腺激素调节的各项生理功能,甚至会导致机体趋于死亡.由于两栖类幼体——蝌蚪的变态发育阶段直接受到甲状腺激素的调控,现已被确认为筛选和研究环境内分泌干扰物的首选生物检测指示动物.  相似文献   
227.
两栖动物生殖内分泌系统(如性别分化、性腺发育、第二性特征)对性激素的敏感性,使得该类动物可用于研究内分泌干扰物(Endocrine Disrupting Chemicals,EDCs)对生殖内分泌系统的干扰作用.两栖动物非洲爪蟾是发育生物学研究的经典模型动物,多年来积累的有关其生殖内分泌的资料可以为生殖内分泌干扰的研究提供参考.论文分析了非洲爪蟾作为评价生殖内分泌干扰作用模型动物的理论基础,总结了评价生殖内分泌干扰作用目前使用的几个指标(性别分化、性腺形态、性腺组织学结构、性激素水平、卵黄蛋白原表达等生物标记),综述了非洲爪蟾在评价酚类化合物、阿特拉津、多氯联苯等几种EDCs的生殖内分泌干扰作用中的应用,最后讨论了非洲爪蟾作为一种评价EDCs生殖内分泌干扰作用的模型动物目前存在的问题.毫无疑问,非洲爪蟾是生殖内分泌干扰研究的良好模型动物,为促进该模型动物更好的应用,需要加强非洲爪蟾生殖生物学和内分泌学的研究.  相似文献   
228.
环境内分泌干扰化合物干扰胰岛素分泌潜在作用机理   总被引:2,自引:1,他引:1  
不断升高的糖尿病发病率在全球范围内引起广泛关注,流行病学调查显示糖尿病发病率的增加与环境内分泌干扰化合物使用量增大之间存在显著相关,环境内分泌干扰化合物可能增加糖尿病发病风险,是影响糖尿病的危险因素。在此背景下,综述了环境内分泌干扰化合物暴露与糖尿病发病之间的流行病学关系;环境内分泌干扰化合物暴露对胰岛β细胞胰岛素分泌的调节、高胰岛素效应及其潜在的作用机理,表明影响胰岛素分泌是环境内分泌干扰化合物调节代谢,诱发糖尿病的重要作用机制。  相似文献   
229.
Effluents from wastewater treatment plant (WWTP) have been reported to have a broad spectrum of endocrine disrupting compounds (EDCs). The majority of studies have focused on the occurrence of estrogenic activity, while ignoring nuclear hormone receptors (NRs) pathways. In the present study, a battery of in vitro yeast bioassays and a cell bioassay, including antagonistic and agonistic effects on estrogen receptor (ER), androgen receptor (AR), progesterone receptor (PR), estrogen- related receptor (ERR) and aryl hydrocarbon receptor (AHR), were conducted to evaluate the removal efficien- cies of EDCs by different treatment processes of a WWTP located in Beijing. Estrogenic, anti-estrogenic, anti- androgenic, anti-progesteronic, anti-ERR and the activa- tion of AHR activities were detected in samples from all treatment processes and the receiving water. The concen- tration of estrogenic contaminants with estradiol (E2) equivalent concentrations ranged from 0.82 x 10-9 to 3.54 x 10 9g Ee_EQ.L-1. The concentration of anti-estrogenic contaminants with 4-hydroxytamoxifen (4-OHT) equiva- lent concentrations ranged from 1.24 × 10-6 to 2.36 x 10-6 g 4-OHT-EQ.L-1. The concentration of anti-androgenic contaminants ranged from 2.21 x 10-s to 3.52 × 10-6g flutamide-EQ. L-1. The concentration of anti-progesteronic contaminants ranged from 3.15 x 10^-5 to 2.71 x 10^-4g RU486-EQ. L-1. The concentration of anti-ERR contami- nants ranged from 7.09 x 10-5 to 6.50 x 104 g 4-OHT-EQ × L^-10. The concentration of AHR activators ranged from 1.7 × 10-10 to 3.4 × 10^-10g TCDD-EQ-L-1. These processes including secondary clarifier, coagulation, as well as coal and sand filtration could eliminated 67.2% of estrogenic contaminants, 47.0% of anti-estrogenic contaminants, 98.3% of anti-androgenic contaminants, 88.4% of anti- progesteronic contaminants, 65.4% of anti-ERR contami- nants and 46.9% of AHR activators. WWTP effluents contain multiple receptor disruptors may have very complex adverse effects on exposed organisms.  相似文献   
230.
Bo Lü 《毒物与环境化学》2013,95(5):1027-1034
In order to determine the effects of nonylphenol (NP) on endocrine regulation-associated gene expression profiles in whole brain of F1 generation rats, mRNA extracted from the brain of 2-day old F1 generation rats whose F0 male generation was treated with NP. The mRNA was then reversely transcribed to cDNA and labeled with cy5 and cy3 fluorescence. Subsequently, cDNA probes were hybridized to the Mouse40S cDNA microarray and the fluorescent signals of cy5 and cy3 were scanned and analyzed. Sixteen genes were identified which expressed differently, including 13 that were down-regulated in which 4 were related to brain regulation of endocrine function. Data suggest that NP mainly affects metabolism and synthesis of steroid hormone in various ways and disturbs the reproductive function of male rats when administered perinatally.  相似文献   
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