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341.
固体发酵提高水生植物发酵产物蛋白含量的研究 总被引:7,自引:1,他引:7
采用微生物固体发酵技术对伊乐藻(Elodea nuttalli)、苦草(Vallinmeria spiralis)和喜旱莲子草(Alterranthera philoxerides)3种高等水生植物进行单细胞蛋白生产的研究,分析单一菌种和混合菌种发酵过程中水生植物粗蛋白含量和纤维素酶活的变化过程.研究结果表明,与单一霉菌发酵相比,利用霉菌与酵母混合发酵,可明显提高发酵产物粗蛋白产量,其中以黑曲霉(Aspergillus niger)与产朊假丝酵母(Candida utilis)混合发酵苦草的粗蛋白含量最高,产物中粗蛋白含量最高可达39.88%,粗蛋白增加率为84.2%,使其有可能成为鱼、家禽和家畜的蛋白饲料来源.因此,利用固体发酵处理水生植物可以实现水生植物的资源化. 相似文献
342.
Aimin Long Chundi Li Shaoyong Chen Wen Yan Aicui Dang Yuanyue Cheng Dongwei Lu 《环境科学学报(英文版)》2010,22(7):975-981
Time-dependent Zn and Cd accumulation and metallothionein like protein (MTLP) induction in the digestive glands of mussels, Perna virdis, were measured under different exposure conditions. The initial uptake rate at start of chase (ρ0) and mean residence time (τ) were calculated to determine the physiological response of organisms and their potential detoxification mechanisms. It was found that in digestive glands, Zn had obviously higher ρ0 and shorter mean residence time than Cd, indicating that these two metals had different accumulation dynamics even though they were very close in the periodic element table. MTLP levels in digestive glands varied from 0.51 to 1.05 μg/g ww (wet weight). The MTLP level increased continuously when mussels were exposed to low and middle levels of Zn and Cd media, and reached maximal levels at day 4, then decreased when they were exposed to high level Zn and Cd solutions. With regard to the fraction of Zn and Cd accumulated in the digestive glands, the ratios of soluble metal to total metal decreased continuously after exposure in low and middle levels of Zn and Cd media, and decreased continuously in the first 4 days and then to level off when mussels were exposed to media with high concentration of Zn and Cd. Results suggested that both MTLP induction and metal insolubilization were detoxification processes in digestive glands of mussels. 相似文献
343.
酸水解法提取剩余污泥蛋白质的条件优化 总被引:3,自引:0,他引:3
为充分提取污水污泥中的细胞蛋白,实现污泥的增值利用,以青岛市李村河污水处理厂剩余污泥为材料,采用酸水解法提取剩余污泥中的蛋白质. 经正交试验综合考察了水解温度、水解时间、反应体系pH和固液比(污泥样品质量(g)/加水体积(mL))等因素对剩余污泥蛋白质提取率的影响. 结果表明:水解温度和反应体系pH对蛋白质提取率的影响较大;通过试验获得的提取污泥蛋白质的最优工艺条件是水解温度为121 ℃,水解时间为5 h,反应体系pH为1.25,固液比为1∶3.0.在上述条件下,剩余污泥蛋白质提取率可达62.71%,水解后的剩余残渣经干燥后测定可知,其质量相对于原污泥样品质量(干重)削减率达到30.49%. 试验证明,选用该法不仅可以达到破解剩余污泥细胞并释放蛋白质的目的,还可以使污泥减量. 相似文献
344.
微囊藻毒素-LR污染饮水的健康风险及其机制 总被引:1,自引:0,他引:1
水体富营养化导致藻类繁殖和水华暴发从而使得藻类释放大量藻毒素,已经演变成为严重的公共卫生问题之一。微囊藻毒素通过饮水严重危害动物和人类的健康安全,最主要的靶器官是肝脏,从而造成肝细胞功能缺陷,比如黄疸和磷酸化活性改变。这些毒性效应主要表现为对磷酸酶的抑制和蛋白磷酸酶活性的调节。综上,微囊藻毒素会造成组织结构损伤、凋亡,即使在低浓度下,也会影响细胞周期,导致肿瘤发生。 相似文献
345.
利用苏云金芽胞杆菌S-层蛋白CTC表面展示系统研究在细胞表面展示鸡毒霉形体粘附素蛋白PMGA1.2的可行性及其免疫原性,为研制能常温长期保藏和运输的禽用口服疫苗奠定基础.用部分pmga1.2基因(pmga1.2p)代替S-层蛋白ctc基因中部且位于表面锚定序列slh下游的片段,构建了2个融合基因ctc-pmga1.2p和csa-ctc-pmga1.2p(csa表csaAB操纵元,其与S-层蛋白牢固地锚定到细胞表面密切相关);将含融合基因的重组质粒电转化入苏云金芽胞杆菌无质粒突变株BMB171中,获得了2个重组菌株BCCG(含ctc-pmga1.2p和携带csaAB操纵元的质粒)和CG(含csa-ctc-pmga1.2p).血凝和血凝抑制试验结果显示,2个重组菌株均成功地在细胞表面展示了重组蛋白PMGA1.2P;小鼠免疫学实验证实,2个重组菌株所展示的重组蛋白均具有免疫原性,其中,重组菌株CG的免疫效果优于BCCG.结果表明,苏云金芽胞杆菌S-层蛋白CTC表面展示系统可被用来研制热稳定性禽用口服疫苗. 相似文献
346.
生物检测标志物和分析方法 总被引:6,自引:0,他引:6
有四种分子水平的生物检测标志物在当前研究环境因素-基因变异-疾病之间相关性的分子生物学领域中起着重要的作用,它们是生物大分子样品的DNA加合物,蛋白质加合物、8-羟基脱氧鸟苷、生物排泄筘的烷基化脱氧嘌呤,因为DNA的特殊作用,DNA加合物作为生物标志物倍受重视,DNA加合物的分析方法有荧光法(灵敏度达1加合物/10^5-6正常核酸),免疫法(灵敏度达1加合物/10^6-8正常核酸),^32P后标记 相似文献
347.
活性污泥胞外聚合物中蛋白质的探针分析方法 总被引:2,自引:0,他引:2
应用微相吸附-光谱修正技术(Microsurface adsorption-spectral correction,简称MSASC),利用刚果红(Congo Red,简称CR)探针测定了活性污泥胞外聚合物(Extracellular polymeric substances,简称EPS)中蛋白质(Protein)的含量,与常用的Folin酚法比较,结果一致,蛋白加标回收率为94.5%~107.1%,相对标准偏差(RSD)<4.5%.对反应机理的分析和产物结合常数的计算结果表明,在pH 2.21时CR-Protein作用符合Langmuir单分子层吸附理论,产物的结合比79∶1,结合常数K=2.17×106,聚集形式为Protein·CR79,摩尔吸收系数ε664r=8.50×105L·mol-1·cm-1. 相似文献
348.
Phytotoxicity of cadmium on growing Arachis hypogaea L. seedlings was studied. Seeds were exposed to 25, 50, and 100 μmol/L CdCl2 concentrations, for a period of 10, 15, 20 and 25 d. The extent of damage to chlorophyll, protein, proline, nitrate and nitrite reductase, antioxidant enzyme activity in leaves and roots were evaluated after 10 d of cadmium stress. The higher concentration of cadmium (100 μmol/L) resulted (leaves and roots) total chlorophyll 91.01%, protein 79.51%, 83.61%, nitrate reductase 79.39%, 80.72% and nitrite reductase 77.07%, 75.88% activity decreased with increase in cadmium concentrations and exposure periods. Cadmium caused significant changes in the activity of antioxidative enzymes. Contrastingly Cd treated plant tissues showed an increase in proline 159.87%, 239.6%, gluthion reductase (GR) 337.72%, 306.14%, superoxide disumutase (SOD) 688.56%, 381.72%, ascorbate peroxidase (APX) 226.47%, 252.14%, peroxidase (POD) 72.19%, 60.29% and catalase (CAT) 228.96%, 214.74% as compared to control. Cadmium stress caused a significant increase in the rate of SOD activity in leaves and roots of plant species. Results show the crop A. hypogaea is highly sensitive even at very low cadmium concentrations. 相似文献
349.
Xiaoshan Zhou Wan Wei Xiaoran Duan Hui Zhang Xiaolei Feng Tuanwei Wang 《Journal of environmental science and health. Part. B》2020,55(6):525-529
AbstractTelomere length was found to be associated with omethoate exposure and polymorphisms in certain genes among occupational workers. However, whether the polymorphisms in telomere-binding protein genes influence telomere length remains unclear. To explore the correlation between telomere length and polymorphisms in telomere-binding protein genes, telomere length in peripheral blood leukocytes was determined by real-time quantitative polymerase chain reaction in 180 omethoate-exposed workers and 115 healthy controls. Polymorphisms in 10 pairs of alleles were detected using flight mass spectrometry or polymerase chain reaction–restriction fragment length polymorphism technique. The results showed that individuals with GG genotype in TRF1 rs3863242 had longer telomere lengths than those with AG?+?AA genotype in the control group (p?=?0.005). The multiple regression analysis suggested that both omethoate exposure (b?=?0.526, p?<?0.001) and TRF1 rs3863242 GG (b?=?0.220, p?=?0.002) were related to a longer telomere length. In conclusion, GG genotype in TRF1 rs3863242 is linked to prolongation of telomere length, and individuals with GG genotype are recommended to strengthen health protection in a Chinese occupational omethoate-exposed population. 相似文献
350.
David N. Skilleter 《毒物与环境化学》2013,95(4):301-312
An involvement of the immune system has been implicated in many of the whole animal effects of beryllium (Be) and its compounds and thus lymphocytes are a relevant cell model to study some of the cellular and molecular actions of the metal. Recent results indicate micromolar concentrations of Be salts are weakly mitogenic to lymphocytes in vitro probably as a result of direct interactions with the cell membranes. Furthermore evidence has been obtained that high affinity lymphocyte Be‐binding may be predictive of the potential to express delayed Be hypersensitivity in vivo. Although sub mitogenic concentrations of Be salts may actually activate accessory (macrophage type) cells, concentrations normally mitogenic to lymphocytes were found to inhibit their proliferative response to accessory cell dependent mitogens as a result of a Be2+ concentration dependent destruction of the adherent cell population. Higher concentrations of Be salts proved cytostatic to lymphocytes possibly by the established property of intracellularly accumulated Be2+ to inhibit cell division. Lymphocyte proliferation can be related to increases in protein phosphoryl‐ation capacity which in vitro can be inhibited by Be2+ and preliminary evidence indicates that tyrosine phosphorylation may be particularly sensitive. 相似文献