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Background
Congenital cytomegalovirus (cCMV) is the most common congenital infection worldwide. cCMV can lead to severe long-term sequelae, including neurological impairment and developmental delay. We performed a systematic review of clinical practice guidelines containing recommendations concerning serological screening for CMV during pregnancy.Method
We performed a search of MEDLINE, Turning Research into Practice (TRIP) database and the grey literature for clinical practice guidelines or consensus statements published in the English language from Jan 2010 to June 2022. The quality of the included guidelines was assessed using the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument. Textual synthesis was used to summarise and compare the recommendations on CMV serological screening in pregnancy.Results
Eleven guidelines and two consensus statements were included. None recommended universal serological screening for CMV in pregnant women; five recommended screening for high-risk women (those with frequent contact with young children). The overall quality of the guidelines varied; most were medium or low.Conclusions
Although clinical practice guidelines do not actively recommend routine serological screening in pregnancy, most did not meet standard processes for development and predated the emerging data on valaciclovir as a potential intervention. Existing recommendations are underpinned by limited, low-level evidence, exposing the lack of robust data in this area of practice. Further high-level evidence and methodologically robust guidelines are needed to guide clinical practice in this rapidly changing field. 相似文献33.
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Application of the New Keystone-Species Concept to Prairie Dogs: How Well Does It Work? 总被引:6,自引:0,他引:6
Natasha B. Kotliar 《Conservation biology》2000,14(6):1715-1721
Abstract: It has been suggested that the keystone-species concept should be dropped from ecology and conservation, primarily because the concept is poorly defined. This prompted Power et al. (1996) to refine the definition: keystone species have large effects on community structure or ecosystem function (i.e., high overall importance), and this effect should be large relative to abundance (i.e., high community importance). Using prairie dogs ( Cynomys spp.) as an example, I review operational and conceptual difficulties encountered in applying this definition. As applied to prairie dogs, the implicit assumption that overall importance is a linear function of abundance is invalid. In addition, community importance is sensitive to abundance levels, the definition of community, and sampling scale. These problems arise largely from the equation for community importance, as used in conjunction with removal experiments at single abundance levels. I suggest that we shift from the current emphasis on the dualism between keystone and nonkeystone species and instead examine how overall and community importance vary (1) with abundance, (2) across spatial and temporal scales, and (3) under diverse ecological conditions. In addition, I propose that a third criterion be incorporated into the definition: keystone species perform roles not performed by other species or processes. Examination of how these factors vary among populations of keystone species should help identify the factors contributing to, or limiting, keystone-level functions, thereby increasing the usefulness of the keystone-species concept in ecology and conservation. Although the quantitative framework of Power et al. falls short of being fully operational, my conceptual guidelines may improve the usefulness of the keystone-species concept. Careful attention to the factors that limit keystone function will help avoid misplaced emphasis on keystone species at the expense of other species. 相似文献
36.
Patricia A. Fair Hing-Biu Lee Jeff Adams Colin Darling Grazina Pacepavicius Mehran Alaee Gregory D. Bossart Natasha Henry Derek Muir 《Environmental pollution (Barking, Essex : 1987)》2009,157(8-9):2248-2254
The presence of triclosan, a widely-used antibacterial chemical, is currently unknown in higher trophic-level species such as marine mammals. Blood plasma collected from wild bottlenose dolphins (Tursiops truncatus) in Charleston, SC (CHS) (n = 13) and Indian River Lagoon, FL (IRL) (n = 13) in 2005 was analyzed for triclosan. Plasma concentrations in CHS dolphins ranged from 0.12 to 0.27 ng/g wet weight (mean 0.18 ng/g), with 31% of the sampled individuals having detectable triclosan. The mean IRL dolphin plasma concentrations were 0.072 ng/g wet weight (range 0.025–0.11 ng/g); 23% of the samples having detectable triclosan. In the CHS area, triclosan effluent values from two WWTP were both 190 ng/L and primary influents were 2800 ng/L and 3400 ng/L. Triclosan values in CHS estuarine surface water samples averaged 7.5 ng/L (n = 18) ranging from 4.9 to 14 ng/L. This is the first study to report bioaccumulation of anthropogenic triclosan in a marine mammal highlighting the need for further monitoring and assessment. 相似文献
37.
Andrew Simon Natasha Pollen Eddy Langendoen 《Journal of the American Water Resources Association》2006,42(1):99-113
Over the past 35 years, a trend of decreasing water clarity has been documented in Lake Tahoe, attributable in part to the delivery of fine grained sediment emanating from upland and channel erosion. A recent study showed that the Upper Truckee River is the single largest contributor of sediment to Lake Tahoe, with a large proportion of the sediment load emanating from streambanks. This study combines field data with numerical modeling to identify the critical conditions for bank stability along an unstable reach of the Upper Truckee River, California. Bank failures occur during winter and spring months, brought on by repeated basal melting of snow packs and rain‐on‐snow events. Field studies of young lodgepole pines and Lemmon's willow were used to quantify the mechanical, hydrologic, and net effects of riparian vegetation on streambank stability. Lemmon's willow provided an order of magnitude more root reinforcement (5.5 kPa) than the lodgepole pines (0.5 kPa); the hydrologic effects of the species varied spatially and temporally and generally were of a smaller magnitude than the mechanical effects. Overall, Lemmon's willow provided a significant increase in bank strength, reducing the frequency of bank failures and delivery of fine grained sediment to the study reach of the Upper Truckee River. 相似文献
38.
Rob Swart Natasha Marinova 《Mitigation and Adaptation Strategies for Global Change》2010,15(6):531-549
Climatic changes more rapid and extreme than assessed by the IPCC cannot be excluded, because of the possibility of positive earth system feedbacks and thresholds. Do today’s policy makers have to take these into account, and if so, are the options different from those considered today? The paper briefly summarizes the types of extreme climatic changes noted in the literature and then evaluates the options to address them in a what-if manner. Different from other studies, which usually look at only one type of measure, we consider a broader portfolio of options: drastic emissions reduction programmes, drawing greenhouse gases from the atmosphere (“carbon dioxide removal”), “emergency cooling” through influencing the radiative balance of the atmosphere (“solar radiation management”), and finally adaptation beyond the options considered seriously today. Politics will have to decide on the choice or mix of “emergency” measures, but research can ensure that such decisions are based on the best scientific information. If through concerted international efforts to mitigate greenhouse emissions low stabilization levels could be reached, such decisions may never have to be made. However, research in support of some form of a “plan B” is now warranted, focusing on those options that have the most positive ratio between potential effectiveness and feasibility on the one hand, and environmental and political risks on the other hand. Such plan should not be limited to one set of options such as geo-engineering and should explicitly take into account not only the relationships between the options but also the wide variety in characteristics of the individual options in terms of effectiveness, feasibility, environmental risks, and political implications. 相似文献
39.
Maria A. van Noordwijk Natasha Arora Erik P. Willems Lynda P. Dunkel Rahmalia N. Amda Neneng Mardianah Corinne Ackermann Michael Krützen Carel P. van Schaik 《Behavioral ecology and sociobiology》2012,66(6):823-834
Female philopatry in mammals is generally associated with ecological and sometimes social benefits, and often with dispersal by males. Previous studies on dispersal patterns of orangutans, largely non-gregarious Asian great apes, have yielded conflicting results. Based on 7?years of observational data and mitochondrial and nuclear DNA analyses on fecal samples of 41 adult Bornean orangutans (Pongo pygmaeus wurmbii) from the Tuanan population, we provide both genetic and behavioral evidence for male dispersal and female philopatry. Although maternally related adult female dyads showed similar home-range overlap as unrelated dyads, females spent much more time in association with known maternal relatives than with other females. While in association, offspring of maternally related females frequently engaged in social play, whereas mothers actively prevented this during encounters with unrelated mothers, suggesting that unrelated females may pose a threat to infants. Having trustworthy neighbors may therefore be a social benefit of philopatry that may be common among solitary mammals, thus reinforcing female philopatric tendencies in such species. The results also illustrate the diversity in dispersal patterns found within the great-ape lineage. 相似文献
40.
Typhenn A. Brichieri-Colombi Natasha A. Lloyd Jana M. McPherson Axel Moehrenschlager 《Conservation biology》2019,33(1):33-39
With the loss of biodiversity accelerating, conservation translocations such as reintroductions are becoming an increasingly common conservation tool. Conservation translocations must source individuals for release from either wild or captive-bred populations. We asked what proportion of North American conservation translocations rely on captive breeding and to what extent zoos and aquaria (hereafter zoos) fulfill captive breeding needs. We searched for mention of captive breeding and zoo involvement in all 1863 articles included in the North American Conservation Translocations database, which comprises journal articles and grey literature published before 2014 on conservation translocations in Canada, the United States, Mexico, the Caribbean, and Central America before 2014 as identified by a comprehensive literature review. Conservation translocations involved captive breeding for 162 (58%) of the 279 animal species translocated. Fifty-four zoos contributed animals for release. The 40 species of animals bred for release by zoos represented only 14% of all animal species for which conservation translocations were published and only 25% of all animal species that were bred for releases occurring in North America. Zoo contributions varied by taxon, ranging from zoo-bred animals released in 42% of amphibian conservation translocations to zero contributions for marine invertebrates. Proportional involvement of zoos in captive-breeding programs for release has increased from 1974 to 2014 (r = 0.325, p = 0.0313) as has the proportion of translocation-focused scientific papers coauthored by zoo professionals (from 0% in 1974 to 42% in 2013). Although zoos also contribute to conservation translocations through education, funding, and professional expertise, increasing the contribution of animals for release in responsible conservation translocation programs presents a future conservation need and opportunity. We especially encourage increased dialogue and planning between the zoo community, academic institutions, and governments to optimize the direct contribution zoos can make to wildlife conservation through conservation translocations. 相似文献