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261.
松花江甲基汞污染危害的环境流行病学研究   总被引:5,自引:0,他引:5       下载免费PDF全文
调查了从第二松花江饮马河口至第一松花江同江全长1271km沿江重点人群受甲基汞污染危害的情况。查出慢性中毒2人,观察对象18人,甲基汞吸收120人。受害者症状轻微,基本稳定,无明显自觉症状。发汞和甲基汞较汞污染治理前有显著下降,说明治理取得了显著的健康效益。但少数人体内仍有过量的汞和甲基汞蓄积,为防止敏感者受害,每周食松花江鱼量不应超过2kg。文中还对诊断、受害者的年龄、性别和发病江段作了讨论。  相似文献   
262.
上海地区果树根癌病发生与土壤环境的关系   总被引:1,自引:0,他引:1  
果树根癌病(致病菌为根癌土壤杆菌Agrobacterium tumefaciens)目前在上海地区大面积发生,严重危害桃(Amygdalus persicaL.)、梨(Pyrus bretschneideri Rehd.)、苹果(Malus pumila Mill.)等果树的生长。本文采用化学分析及微生物培养等方法,研究了上海地区桃树和梨树根癌病的发生与土壤因子(土壤含水量、pH值、有机质含量),土壤细菌以及与不同果树品种之间的关系。结果表明:土壤含水量、pH值、有机质含量、土壤中微生物的多样性和微生物总体数目与病害的发生没有显著的相关性,但是土壤中存在的个别菌种对病害的发生有显著的影响,初步分析显示Agrobacterium sp.和Bacillus sp.对根癌病的发生具有抑制作用,而Psuedomonas sp.对根癌病的发生可能具有一定的促进作用。同时不同果树品种的病害发生率之间有显著性的差异。  相似文献   
263.
高东 《生态环境》2010,19(8):1999-2003
农业集约化生产方式加速了农业生态系统单一化的进程,导致系统平衡破坏,病、虫、草害频发。在以农业生态环境改善和修复为手段的农业可持续生产和发展的模式中,以农作物多样性的合理布局来提高农业生物多样性水平和控制病、虫、草害的实践,显示出其强大的生命力,即将不同物种的作物或同一作物的不同品种按一定的组合方式和栽种模式进行合理的间栽和套作,将病、虫、草害的发生控制在可以承受的范围内。构建水生动物、水生植物与水稻共存的稻作系统,利用物种多样性、遗传多样性控制有害生物,是农业可持续发展的重要途径。本文综述了国内外稻田物种多样性、遗传多样性利用模式的研究进展,论述了稻田物种多样性、遗传多样性对稻作生态系统的改善,特别是水稻病、虫、草的控制效果及作用机理。  相似文献   
264.
为定量评估突发公共卫生事件下的公交暴露风险,基于公交线网、交通分析区及新型冠状病毒肺炎(COVID-19)疫情信息等多源数据,考虑公交站点、交通分析区及疫情场所3种研究尺度,集成公交网络结构拓扑模型、公交网络中心性模型及核密度分析等空间分析方法,提出公交暴露风险的多尺度辨识方法,并以深圳市为例进行验证。结果表明:公交站点暴露风险在空间上呈现多中心—圈层结构,较高及高暴露风险站点多为交通枢纽、商场等,占比达26.40%;较高及高暴露风险交通分析区主要分布在工业、商业聚集区及居民点密集区,占比达32.84%;较高及高暴露风险疫情场所主要集中在城市核心区域,占比为28.92%。  相似文献   
265.
The purpose of this study is to estimate the environmentally attributable costs associated with diseases and disabilities in Oregon. We utilised actual Oregon data on disease rates and costs whenever available. If state-specific data were not available, we extrapolated from national estimates. We then used environmentally attributable fractions to estimate the environmentally attributable costs. The estimated environmentally attributable costs are the following: adult and childhood asthma: $29.6M; adult cardiovascular disease: $342.4M; adult and childhood cancer: $130.5M; childhood lead poisoning: $866.2M; birth defects: $3.0M; and childhood neurobehavioural disorders: $185M. Policymakers and researchers in other states are encouraged to apply the methods we have presented here to calculate the environmentally attributable costs associated with diseases and disabilities in their state. Knowing that many of the environmental contributors to disease are often preventable, policymakers are encouraged to make environmental public health a top priority.  相似文献   
266.
In its role as a competitive producer of phosphate and potash Jordan has not suffered noticeably from the Resource Curse over the past 50 years. However, the effects on its economy because of its geographical proximity to major oil-producing states have been both positive and negative. It is arguable that an oil resource curse has applied to Jordan.  相似文献   
267.
268.
Predicting and preventing outbreaks of infectious disease in endangered wildlife is problematic without an understanding of the biotic and abiotic factors that influence pathogen transmission and the genetic variation of microorganisms within and between these highly modified host communities. We used a common commensal bacterium, Campylobacter spp., in endangered Takahe (Porphyrio hochstetteri) populations to develop a model with which to study pathogen dynamics in isolated wildlife populations connected through ongoing translocations. Takahe are endemic to New Zealand, where their total population is approximately 230 individuals. Takahe were translocated from a single remnant wild population to multiple offshore and mainland reserves. Several fragmented subpopulations are maintained and connected through regular translocations. We tested 118 Takahe from 8 locations for fecal Campylobacter spp. via culture and DNA extraction and used PCR for species assignment. Factors relating to population connectivity and host life history were explored using multivariate analytical methods to determine associations between host variables and bacterial prevalence. The apparent prevalence of Campylobacter spp. in Takahe was 99%, one of the highest reported in avian populations. Variation in prevalence was evident among Campylobacter species identified. C. sp. nova 1 (90%) colonized the majority of Takahe tested. Prevalence of C. jejuni (38%) and C. coli (24%) was different between Takahe subpopulations, and this difference was associated with factors related to population management, captivity, rearing environment, and the presence of agricultural practices in the location in which birds were sampled. Modeling results of Campylobacter spp. in Takahe metapopulations suggest that anthropogenic management of endangered species within altered environments may have unforeseen effects on microbial exposure, carriage, and disease risk. Translocation of wildlife between locations could have unpredictable consequences including the spread of novel microbes between isolated populations.  相似文献   
269.
Island populations are vulnerable to introduced pathogens, as evidenced by extinction or population decline of several endemic Hawaiian birds caused by the malaria parasite, Plasmodium relictum (order Haemosporida). We analyzed blood samples from 363 birds caught near Guantánamo Bay, Cuba, for the presence of haemosporidian infections. We characterized parasite lineages by determining nucleotide variation of the parasite's mitochondrial cyt b gene. Fifty‐nine individuals were infected, and we identified 7 lineages of haemosporidian parasites. Fifty individuals were infected by 6 Haemoproteus sp. lineages, including a newly characterized lineage of Haem. (Parahaemoproteus) sp. CUH01. Nine individuals carried the P. relictum lineage GRW4, including 5 endemic Cuban Grassquits (Tiaris canorus) and 1 migratory Cape May Warbler (Setophaga tigrina). A sequence of the merozoite surface protein gene from one Cuban Grassquit infected with GRW4 matched that of the Hawaiian haplotype Pr9. Our results indicate that resident and migratory Cuban birds are infected with a malaria lineage that has severely affected populations of several endemic Hawaiian birds. We suggest GRW4 may be associated with the lack of several bird species on Cuba that are ubiquitous elsewhere in the West Indies. From the standpoint of avian conservation in the Caribbean Basin, it will be important to determine the distribution of haemosporidian parasites, especially P. relictum GRW4, in Cuba as well as the pathogenicity of this lineage in species that occur and are absent from Cuba.  相似文献   
270.
以某物探公司为例,分析阐述了物探行业心脑血管疾病高发的主要原因,从完善体检筛查、合理安排工作、改善工作条件、应急能力建设、宣传健康知识等方面,探讨了预防石油物探企业员工心脑血管疾病的措施。  相似文献   
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