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71.
Hydrogen sulfide (H2S) is an endogenous gaseous molecule, functioning as a physiological regulator. This study aimed to investigate the role of H2S in atherosclerosis. Rabbits receiving high cholesterol were given atorvastatin (10 mg/kg/day, orally) or sodium sulfide (1.1 mg/kg/day, intramuscular) 2 weeks after commencement of high-cholesterol diet and continued for 4 weeks. Serum lipid profiles, lipid peroxidation indexed as malondialdehyde, glutathione, superoxide dismutase, the vascular adhesion molecule-1, and aortic vascular endothelial growth factor were determined. Rabbits receiving a high-cholesterol diet showed elevated levels of total serum cholesterol, triglycerides, low-density lipoprotein cholesterol, malondialdehyde and vascular adhesion molecule-1, and aortic vascular endothelial growth factor expression and lower levels of high-density lipoprotein cholesterol, glutathione, and superoxide dismutase. Treatment with atorvastatin and sodium sulfide has beneficial effects on serum lipid profile, oxidative damage, vascular adhesion molecule-1, and aortic expression of vascular endothelial growth factor.  相似文献   
72.
The environmental planning and management of the Assarawat highlands of south-western Saudi Arabia are currently confronted by difficult problems. Deforestation is caused either by natural or intentional forces. Natural factors are limited to lightning fire and drought, while intentional forces include vandalism caused by the burning or cutting of preserved forests. Such vandalism continues despite the tremendous efforts of afforestation and preservation by several government agencies, especially the Ministry of Agriculture and Water, the National Commission for Wildlife Conservation and Development and by the municipalities of the cities and towns in the region. For centuries, local inhabitants of the Assarawat highlands have successfully established environmental planning and management strategies which balanced the settlements' growth and natural resource uses according to Islamic laws, and the tribal self-government of each settlement and tribal region. Following the establishment of the Kingdom of Saudi Arabia in 1932, the land management system started to change from tribal-based, where every tribe used to manage its local territory, to State authority. The creation of the State witnessed the unification of various fragmented tribes of Saudi Arabia into one government. This meant that environmental planning and management moved from local/regional towards a national control. This investigation proposes that the local/regional planning and management practised by the tribes could be viably utilized today. As in the past, the implementation of these practices could protect the natural environment of the locality and region and regularize their exploitation rationally, as long as vernacular people implement them. Today environmental planning and management need to be based on strategies of local requirements that enable the indigenous people to plan and manage the use of the resources.  相似文献   
73.
Environmental Science and Pollution Research - This experiment was conducted to study that effect of a phytogenics (herbal mixture) supplementation as alternative to antibiotics on the growth...  相似文献   
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The kinetics of the degradation of trace nitrobenzene (NB) by a granular activated carbon (GAC) enhanced microwave (MW)/hydrogen peroxide (H2O2) system was studied. Effects of pH, NB initial concentration and tert-butyl alcohol on the removal efficiency were examined. It was found that the reaction rate fits well to first-order reaction kinetics in the MW/GAC/H2O2 process. Moreover, GAC greatly enhanced the degradation rate of NB in water. Under a given condition (MW power 300 W, H2O2 dosage 10 mg/L, pH 6.85 and temperature (60±5)℃), the degradation rate of NB was 0.05214 min-1 when 4 g/L GAC was added. In general, alkaline pH was better for NB degradation; however, the optimum pH was 8.0 in the tested pH value range of 4.0-12.0. At H2O2 dosage of 10 mg/L and GAC dosage of 4 g/L, the removal of NB was decreased with increasing initial concentrations of NB, indicating that a low initial concentration was beneficial for the degradation of NB. These results indicated that the MW/GAC/H2O2 process was effective for trace NB degradation in water. Gas chromatography-mass spectrometry analysis indicated that a hydroxyl radical addition reaction and dehydrogenation reaction enhanced NB degradation.  相似文献   
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77.
Environmental Science and Pollution Research - A study is presented on the enhancement of solar still (SS) performance by using chimney exhaust gases (EGs) passing through chimney channels under...  相似文献   
78.
Environmental Geochemistry and Health - Modeling metal sorption in soils is of great importance to predict the fate of heavy metals and to assess the actual risk driven from pollution. The present...  相似文献   
79.
When in 2010 the world's governments pledged to increase protected area coverage to 17% of the world's land surface, several Central African countries had already set aside 25% of their northern savannas for conservation. To evaluate the effectiveness of this commitment, we analyzed the results of 68 multispecies surveys conducted in the seven main savanna national parks in Central Africa (1960–2017). We also assembled information on potential drivers of large herbivore population trends (rainfall and number of rangers) and on tourist numbers and revenues. In six out of the seven parks, wild large herbivore populations declined dramatically over time, livestock numbers increased severalfold, and tourism, the pillar under a once thriving local wildlife industry, collapsed. Zakouma National Park (Chad) stood out because its large herbivore populations increased, an increase that was positively correlated with rainfall and number of rangers (a proxy for management inputs). With increasing insecurity and declining revenues, governments find themselves confronted with too few resources to protect vast areas. To deal with this conversation overstretch, we propose to extend the repeatedly promoted solutions––scaled up funding, enhanced management––with a strategic retreat, focusing scarce resources on smaller areas to save wildlife in the Central African savannas.  相似文献   
80.
Environmental Chemistry Letters - Lithium batteries are increasingly used to store energy, but are limited by high cost, safety concerns, leaking of electrolytes, and low capacity....  相似文献   
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