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21.
Under the intensive agricultural system, direct application of animal slurries to soils can provide a sustainable disposal of these wastes by inducing positive changes in soil quality and fertility. However, how animal wastes quantitatively affect the key nutrients (C, N, P and S) transforming soil enzymes is not clearly known. A greenhouse spinach cultivation study demonstrated that pig slurry, either in raw (RS) or processed (aerobically aged) (PS) form, significantly (p?β-glucosidase (23–39%), urease (59–103%), nitrate reductase (73–103%) and dehydrogenase (27–72%)) and microbial growth in soil as compared to the unamended control. However, it did not significantly (p?>?.05) alter the aryl sulphatase enzyme activity. Slurry applications also significantly improved the macro (N, P and K) and micronutrients (Cu, Mn, Zn and Fe) uptake by spinach plant and hence the yield (2.9–3.38 times higher than control). Similarly, compared to chemical fertilisers the application of pig slurries improved soil biological and biochemical parameters as well as plant nutrients uptake. This study demonstrated the closing of global energy and nutrient cycles through land application of animal wastes without compromising the crop yield.  相似文献   
22.
The ever-increasing use of pesticides in the agricultural and public health has become a major cause of sterility in human and various other animals particularly in males. This study was sought to screen the toxic impacts of cypermethrin (synthetic pyrethroid) on reproduction and development. Twenty-four Wistar male rats divided into four groups were orally administered cypermethrin of daily doses 50, 75, or 100 mg?kg?1 bwt per day for 45 days; and for developmental toxicity, 12 female rats were separated into two groups. Maternal rats (experimental) were administered cypermethrin (100?mg?kg?1) by gavage daily from 6th to 17th day of gestation, and the control group was dosed only vehicle (olive oil). The body weights, fertility index, biochemical, enzymatic, hormonal, and histopathological parameters were the criteria used to evaluate the toxicity of cypermethrin. Study showed significant decline in the weight of testes, epididymises, seminal vesicles, and ventral prostate, and reduction in sperm counts both in epididymises and testes in chemical-treated animals. Pre- and post- fertility test showed 50%, 80%, and 100% negative results after treatment. A significant degenerative reduction in testicular glycogen and sialic acid was also noted. In contrast, protein and cholesterol levels of testes were significantly increased. In addition, acid phosphatase activity was significantly increased, while alkaline phosphatase, testosterone, leutinizing hormone (LH), and follicle stimulating hormone (FSH) levels were diminished. Histology of testes showed degenerative changes in seminiferous tubules. Cypermethrin exposure during gestation produced adverse effects markedly in females and fetuses.  相似文献   
23.
Fertility is declining in many countries and there has been substantial interest in the potential adverse effects of exposure to environmental hazardous chemicals, including pesticides on male reproduction. Organophosphorous compounds (organophosphates, OP) constitute a heterogeneous category of chemicals specifically designed for the control of pests or plant diseases. OP are known to produce reproductive toxicity, resulting in a decrease in the fertility levels of humans and animals. This review article mainly focused on toxicity of some OP such as acephate, chlorpyrifos, diazinon, dimethoate, fenitrothion, malathion, and monocrotophos especially dealing with reproductive toxicity in males. Furthermore, this review deals with mode of action and clinical syndromes of OP. Considerable lab studies on animals concluded that OP produce adverse effects on male reproductive system.  相似文献   
24.
Biological activity of neem seeds, leaves and bark is well-established as feeding deterrent and growth disrupter against insects and other arthropods. Neem is a valuable natural pesticide with low toxicity for vertebrates. However, it has not yet achieved a prominent place among pesticides due to its unstability. Recent studies have focused on newer formulations like microencapsulation, inclusion complexes, microemulsion, and granular formulations to enhance efficacy shelf life. Several studies have been undertaken on the effects of neem on predator, parasitoids, and other beneficial organisms as well as impact on the environment. Biotechnological interventions have been carried out for mass production of the active molecule. Once stable formulations of the active molecules are developed, the farming community will benefit the most due to the low toxicity and marked efficacy of neem insecticides.  相似文献   
25.
Lead (Pb) is a heavy metal, known to induce oxidative stress and produce damage to the antioxidant defence system ultimately leading to cell death. Antioxidants such as epigallocatechin 3-gallate (EGCG), a green tea polyphenol, was shown to play a protective role during Pb-exposure. In this study, human SH-SY5Y neuroblastoma cells were exposed to different concentrations (0.01–10?µM) of Pb for 48?h to determine effects on the viability of cells. It was observed that IC50 was at 5?µM and at this concentration the cells exhibited a significant increase in caspase-3 activity, an indicator of apoptosis at least by 10-fold and the decrease of 59.4% in glutathione (GSH) content. The total cellular prostaglandin-E2 (PGE2) level was found to be elevated at least 10-fold upon Pb exposure. However, the effects of Pb on cells pre-incubated with 50?µM EGCG followed by 5?µM Pb showed 40% inhibition in cell viability, 17.3% decrease in caspase-3 activity, 23% increase in GSH content, and 11.4% fall in PGE2 levels when compared with cells exposed to Pb only. Data suggest that EGCG exerted a significant protection to cell viability in preventing cell death and elevation in levels of GSH in cells exposed to Pb. However, EGCG did not elicit any significant effect on release of PGE2 indicating the nature of EGCG as an effective anti-apoptotic, antioxidant, and anti-inflammatory agent.  相似文献   
26.
This paper presents the status of sustainable livelihood security index (SLSI) of Karnataka, the most drought prone state in the Southern part of India. Computation of ecological security index, economic efficiency index and social equity index, and finally SLSI were carried out at the district level for the entire state, using empirical data. The selected indicators were first normalised, and then using estimated weights, indices were computed. The results indicate that the state has a very low SLSI with only 27.6% of total geographical area (TGA) and 21.7% of population being placed in the ‘sustainable’ and ‘highly sustainable’ categories (covering 10 districts) while only 34% of the TGA covering six districts falls in the ‘moderately sustainable’ category. The remaining area, confined mostly to the northern parts of the state, comprising 14 districts (51.8% of the state’s TGA) is categorised as ‘less sustainable’ and ‘very less sustainable’ exposing 44.4% (27.14 million) of state’s population to the perils of uncertain rainfall, high soil erosion rates, high social inequality and poor resource use efficiency. There is an urgent need to reorient development programmes and prioritise development investments in these vulnerable districts so that they are provided resources and opportunities to improve their ecological (more forest cover and less soil erosion), economic (higher agricultural productivity) and social (improved health and education facilities and rural infrastructure) status and achieve sustainable levels of livelihood.  相似文献   
27.
Journal of Polymers and the Environment - In this study, we prepared Poly (vinyl alcohol) (PVA)/Guar gum (GG) based nanocomposite films with a different weight ratio of silver nanoparticles (AgNPs)...  相似文献   
28.
29.
Abstract

Fusarubin analogues of Fusarium oxysporum f. sp. ciceris were investigated for antifungal activity in vitro against five soil borne phytopathogenic fungi. 3-O-Methyl-8-O-methyl-fusarubin was inhibitory towards S. sclerotiorum (EC50 0.33?mmol L?1) and Sclerotium rolfsii (EC50 0.38?mmol L?1). A structure–antifungal activity relationship of fusarubin analogues was established from their activity performance. Possible mechanism of action of these compounds was studied using molecular docking and simulations against three target enzymes which revealed receptor ligand binding affinity. Docking of 3-O-methyl-8-O-methyl-fusarubin into the succinate dehydrogenase site revealed formation of salt bridge, hydrogen bond, π–anion, π–alkyl, and Van der Waals interactions.  相似文献   
30.
Exposure to environmental pollutants is known to be harmful to health, in general, and to lungs in particular. In this respect, traffic police are at particular risk due to the nature of their job, since they are exposed to emissions from the vehicles. Here, we show that in the traffic police of Hyderabad city, India, the plasma levels of lipid peroxides are high, whereas the concentrations of the nitric oxide are low. In addition, the levels of various antioxidants in the RBC lysate such as catalase, superoxide dismutase and glutathione peroxidase were found to be low with no significant alteration in plasma ceruloplasmin levels. These results suggest that exposure to air pollutants, a major portion of which is due to emissions from the vehicles, can increase oxidant stress, decrease the levels of antioxidants and nitric oxide. This imbalance in the oxidant/antioxidant system may lead to lung damage and is likely to cause respiratory problems in individuals exposed to air pollution.  相似文献   
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