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411.
为有效引导和管控突发公共卫生事件网络舆情,考虑社会相关性和网络群体间情绪状态转移的不确定性,基于社会燃烧理论研究突发公共卫生事件网络情绪传播机制.首先基于社会燃烧理论分析网络用户群体的社会影响因素,建立未燃-阴燃-燃烧-抑燃-稳定(UDBFS)网络情绪传播模型和考虑干预措施的网络情绪传播模型;然后以新冠肺炎(COVID... 相似文献
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413.
Ben Mepham 《Journal of Agricultural and Environmental Ethics》2001,14(3):339-347
The 2001 Foot and Mouth Diseaseoutbreak in the UK has had widespread adverseeffects – on the farming community, thetourist industry, millions of farm animals, theenvironment, and citizens' quality of life.This report summarizes the course of theepidemic and then questions the ethicalvalidity of the procedure chosen to eradicatethe disease, namely, the slaughter of millionsof animals. It is argued that the utilitarianbasis of the mass slaughter program isunjustified even in its own terms, and thatrespect for certain deontological principlesmerits increased attention in public policy.The long-term interests of UK citizens, theviability of British farming, and theconservation of the countryside all depend onurgent, critical decisions that should beinformed by a broader conception of the role ofethics in agriculture. 相似文献
414.
A pregnant woman has two children affected by moderately severe Hb H disease due to compound heterozygosity of South-east Asian deletion and Constant Spring mutation. In her third pregnancy, transabdominal chorionic villus sampling was performed at the tenth gestational week to obtain fetal DNA. The polymerase chain reaction was used for detection of both the South-east Asian deletion and the Constant Spring mutation. Hb H disease was diagnosed in the fetus. After genetic counselling, the couple elected to have the pregnancy terminated. 相似文献
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416.
KELSEY J. RIPP MELANIE BERGER JANE CHEN JUSTIN DITTMEIER MAGGIE GOTER STEPHEN T. MCGARVEY ELIZABETH RYAN 《Conservation biology》2013,27(6):1378-1388
At local scales, infectious disease is a common driver of population declines, but globally it is an infrequent contributor to species extinction and endangerment. For species at risk of extinction from disease important questions remain unanswered, including when does disease become a threat to species and does it co‐occur, predictably, with other threats? Using newly compiled data from the International Union for Conservation of Nature (IUCN) Red List, we examined the relative role and co‐occurrence of threats associated with amphibians, birds, and mammals at 6 levels of extinction risk (i.e., Red List status categories: least concern, near threatened, vulnerable, endangered, critically endangered, and extinct in the wild/extinct). We tested the null hypothesis that the proportion of species threatened by disease is the same in all 6 Red List status categories. Our approach revealed a new method for determining when disease most frequently threatens species at risk of extinction. The proportion of species threatened by disease varied significantly between IUCN status categories and linearly increased for amphibians, birds, and all species combined as these taxa move from move from least concern to critically endangered. Disease was infrequently the single contributing threat. However, when a species was negatively affected by a major threat other than disease (e.g., invasive species, land‐use change) that species was more likely to be simultaneously threatened by disease than species that had no other threats. Potential drivers of these trends include ecological factors, clustering of phylogenetically related species in Red List status categories, discovery bias among species at greater risk of extinction, and availability of data. We echo earlier calls for baseline data on the presence of parasites and pathogens in species when they show the first signs of extinction risk and arguably before. La Amenaza de Enfermedades Incrementa a Medida que las Especies se Aproximan a la Extinción 相似文献
417.
The purpose of this paper is to explore the use of computer models, including artificial intelligence systems, in the context of risk assessment and management for wildfowl diseases. In particular, the paper focuses on avian cholera and botulism in U.S. wildfowl, which are a source of continuing concern to the U.S. Fish and Wildlife Service (USFWS). Severe outbreaks occur frequently, and some have been estimated to claim the lives of as many as 300 000 waterfowl. A potentially valuable support to the USFWS would be a set of models that assist in recognizing situations with high risk of an outbreak, assessing the anticipated severity of an outbreak, and advising on possible preventive measures. The USFWS has already initiated development of several potentially useful models. This paper reviews these as well as other related efforts, within the overall context of risk management for avian botulism and cholera. 相似文献
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419.
Prenatal diagnosis of Gaucher disease, the most prevalent glycolipid storage disease, is based on a reliable enzyme assay of cells from amniocentesis or chorionic villous samples. However, this method cannot differentiate among the various forms of the disease. This report details four cases of prenatal diagnosis of Gaucher disease, three of which predate the use of molecular diagnosis. DNA mutation analysis to determine the genotype was predictive of the phenotypic status of the fetus and conformed to the genotype of an affected proband where available. 相似文献
420.
遥感和GIS在森林病虫害监测管理中的应用模式 总被引:20,自引:1,他引:19
介绍了遥感技术,地理信息系统技术在森林病虫害监测管理中的应用模式,以及整个系统的集成。在整个系统中遥感用于获取森林病虫害信息,地理信息系统用于管理和处理森林病虫害信息。同时,也说明了全球定位系统可用于定位采集地面数据和导路。 相似文献