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191.
192.
Catherine D. Kashork V. Reid Sutton Jill S. Fonda Allen Deborah E. Schmidt Marisa L. Likhite Lorraine Potocki William E. O'Brien Lisa G. Shaffer 《黑龙江环境通报》2002,22(11):1028-1032
It has been previously reported that a low or absent maternal serum unconjugated estriol (uE3) level is associated with placental steroid sulfatase (STS) deficiency. Here we report a correlation between patients who present with a very low or absent maternal serum uE3 and a deletion of the STS gene as assessed by fluorescence in situ hybridization (FISH). We studied nine prenatal cases that presented to the clinical laboratory with an abnormal triple screen, specifically low or absent maternal serum uE3 and a 46,XY karyotype. FISH analysis showed complete deletion of a probe containing the STS gene in six cases and one case had a partial deletion (reduced but not absent signal). The remaining two cases were not deleted for the STS probe. All mothers tested whose fetus showed a deletion were shown to be STS deletion carriers using FISH. Biochemical analysis was performed on 7/9 prenatal specimens. All fetuses deleted for the STS probe were also found to be deficient for STS by biochemical analysis of cultured amniotic fluid (5/5). Of the two fetuses not deleted for the STS probe, one was deficient for STS activity, while the other had a normal result. The abnormal result of enzyme deficiency by biochemical analysis in a non-deletion case likely represents a mutation in the STS gene, not detectable by this FISH assay. Postnatal FISH confirmation of the STS deletion was performed in 1/7 cases. Clinical follow-up was available for 4/9 cases following birth. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
193.
Jonathan J. Waters Sally Walsh Lisa J. Levett Stuart Liddle Yinka Akinfenwa 《黑龙江环境通报》2006,26(10):892-897
A chorion villus sample (CVS) biopsied at 11 weeks' gestation for raised nuchal translucency, revealed monosomy X (presumptive 45,X karyotype) by QF-PCR for rapid aneuploidy testing for chromosomes 13, 18, 21, X and Y. Long-term culture gave the karyotype: 47,XY,+ 21[66]/49,XYY,+ 21,+ 21 [22]. This discrepancy prompted redigestion of the combined residual villus fragments from the original QF-PCR assay. The repeat QF-PCR assay identified the presence of trisomy 21 and a Y chromosome consistent with a 47,XY,+ 21 karyotype. A double non-disjunction event early in embryogenesis in a 47,XY,+ 21 conceptus with subsequent cell lineage compartmentalisation of the three observed cell lines (45,X; 47,XY,+ 21 and 49,XYY,+ 21,+ 21) would account for these results. This is the first reported case to describe complete discrepancy at diagnosis between abnormal karyotypes detected by QF-PCR rapid aneuploidy testing and a cultured karyotype in the same CVS. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
194.
Lisa G. Shaffer 《黑龙江环境通报》2006,26(4):303-307
Carriers of nonhomologous Robertsonian translocations (ROB) are at risk for having offspring with uniparental disomy (UPD). Although risk estimates have been calculated in several independent studies, the estimates have not been optimal because most studies are not of sufficient size and UPD events are rare. However, these collective data have provided the opportunity to derive an overall risk estimate for UPD in the fetus after the prenatal identification of a ROB. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
195.
Filippi L Baba N Inadomi K Yanagi T Hironaka M Nomakuchi S 《Die Naturwissenschaften》2009,96(2):201-211
In recent years, three terrestrial bugs, Adomerus triguttulus and Sehirus cinctus (Cydnidae) and the closely related Parastrachia japonensis (Parastrachiidae), have been the focus of several fascinating studies because of the remarkable, extensive parental care they were found to display. This care includes egg and nymph guarding, production of trophic eggs, unfertilized, low cost eggs that are used as food by newly hatched nymphs, and progressive provisioning of the host seed. In this study, we have investigated yet a third related Asian cydnid, Canthophorus niveimarginatus, with regard to the possible occurrence of some or all of these complex traits in order to assess how widespread these maternal investment patterns are in this group of insects and to better understand the implications of their manifestations from an evolutionary context. Manipulative experiments were carried out in the lab to determine whether females provision nests. Observational and egg removal studies were carried out to determine whether trophic eggs are produced, and, if they are, their possible impact on nymphal success. The findings revealed that C. niveimarginatus does, in fact, progressively provision young, and this species also displays all of the other behaviors associated with extended parental care in subsocial insects. Moreover, unlike the other two related species, which place trophic eggs on the surface of the original egg mass, C. niveimarginatus produces both pre- and post-hatch trophic eggs. Nymphs deprived of access to post-hatch trophic eggs had significantly lower body weight and survival rate than those that fed on them. To our knowledge, this is the first time the production of both pre- and post-hatch trophic eggs has been demonstrated in insects outside the Hymenoptera. In this paper, we qualitatively and quantitatively demonstrate the provisioning behavior and patterns of trophic egg production in C. niveimarginatus. When and how trophic eggs are produced and delivered to young should have important correlations with the ecological and life history constraints under which a species has evolved. Thus, we also discuss the possible ecological and life history factors that favor the evolution of post-hatch trophic eggs. 相似文献
196.
INTRODUCTION: The purpose of the study reported here was to develop and pilot test a comprehensive battery of assessment instruments for older drivers that would be inexpensive and easy to administer so that it could be used in longitudinal studies. METHOD: The resulting battery was developed by selecting a set of validated assessment instruments and combining them into a package, with a total acquisition cost of less than $900. As part of this battery, three questionnaires were developed utilizing items from established questionnaires with minor modifications. The battery was pilot tested with a convenience sample of 38 drivers aged 65 years or older. RESULTS: Results showed that the entire battery required less than one hour to complete. Data from the assessment outcomes fell within normative ranges. Feedback from subjects indicated that the battery was acceptable, free of problems, presented tasks in a good order, and was not too long. CONCLUSIONS: Based on study findings, the assessment battery appeared to be low-cost, transportable, easy to administer, easy for subjects to complete, provides a comprehensive assessment of a person's physical health, mental health, and driving behaviors, and would serve as a valuable data collection tool for a longitudinal study of older drivers. Such a longitudinal study is needed in order to answer some of the most important questions about older driver safety and mobility. 相似文献
197.
Australian owlet-nightjars (Aegotheles cristatus; ~50?g) are one of only a few avian species that roost in cavities year-round and regularly enter torpor. Cavity roosts act as thermal buffers, and roost type likely affects energy expenditure of small birds. We used radiotelemetry to locate diurnal winter roost sites of owlet-nightjars in central Australia and to measure body (T (b)) and skin (T (skin)) temperature. We also recorded ambient temperature inside (T (IN)) and outside roosts. Individual owlet-nightjars used one to seven different roosts (tracking time 3-10?weeks), selecting either rock crevices (four birds) or tree hollows (four birds), or switching between the two roost types (seven birds). Rock crevices (T (IN) +9°C to +33°C) were warmer and thermally more stable than tree hollows (T (IN) -4.0°C to +37°C). Torpor, often expressed by a reduction of T (skin)/T (b) by >10°C for 3-4?h at dawn, was influenced by roost selection; torpor use in tree hollows was almost twice that in rock crevices. Despite the potential energy savings accrued from roosting in well-insulated cavities, owlet-nightjars roosted in tree hollows more often (65% bird days, n?=?398) than in rock crevices (35% bird days, n?=?211). Lower costs of arousal from torpor via passive rewarming and basking and decreased risk of predation are two possible explanations for the preference to roost in tree hollows. We provide the first evidence for the influence of cavity roost selection on torpor use in a free-ranging bird and show that roost selection and thermal biology are strongly interrelated in determining energy expenditure. 相似文献
198.
Le Thuy Minh Pham Phuong Thi Nguyen Truong Quang Nguyen Trung Quang Bui Minh Quang Nguyen Hoa Quynh Vu Nam Duc Kannan Kurunthachalam Tran Tri Manh 《Environmental science and pollution research international》2022,29(31):46767-46777
Environmental Science and Pollution Research - Seven parabens including methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), iso-propylparaben (iPrP), butylparaben (BuP), benzylparaben... 相似文献
199.
This paper presents an agile participatory urban soundscape planning process model, which is proposed as a prerequisite on which to build and reference the efficacy of urban soundscape planning. The model was developed through data synthesis and analysis and mapping engagement with diverse stakeholders across four applied soundscape projects in Brighton and Hove, UK. To the best of the authors’ knowledge, the model is the first of its kind in applied soundscape practice. The data was collected through semi-structured interviews with key stakeholders and document analysis of published resources. The framework used for the analysis of the findings comprised four core urban planning stages: goals and objectives, engagement (e.g. prediction/modelling/design/planning), implications, evaluation. The study found that when integrating soundscape planning with core urban planning stages it was necessary to first identify the appropriate stakeholders in relation to the project context. It was found that these stakeholders could be wide-ranging and unexpected, thereby reinforcing the appropriateness of incorporating an agile approach in the resulting model. The study also found that users’ perceptions are central to soundscape practice and need to be considered at each stage of a planning process to produce an effective and sustainable outcome. A variety of specific events, appropriate to the requirements of the stakeholders, are important for engaging planning authorities, users and other stakeholders at different stages. This study also demonstrated that an evidence-based evaluation method is recommended in an agile participatory urban soundscape planning process to assess stakeholders’ engagement at each stage and to inform and guide subsequent steps in the planning process relevant to the local context(s). 相似文献
200.
Benjamin J. Koch Catherine M. Febria Muriel Gevrey Lisa A. Wainger Margaret A. Palmer 《Journal of the American Water Resources Association》2014,50(6):1594-1607
A comprehensive synthesis of data from empirically based published studies and a widely used stormwater best management practice (BMP) database were used to assess the variability in nitrogen (N) removal performance of urban stormwater ponds, wetlands, and swales and to identify factors that may explain this variability. While the data suggest that BMPs were generally effective on average, removal efficiencies of ammonium (NH4), nitrate (NO3), and total nitrogen (TN) were highly variable ranging from negative (i.e., BMPs acting as sources of N) to 100%. For example, removal of NO3 varied from (median ±1 SD) ?15 ± 49% for dry ponds, 32 ± 120% for wet ponds, 58 ± 210% for wetlands, and 37 ± 29% for swales. Across the same BMP types, TN removal was 27 ± 24%, 40 ± 31%, 61 ± 30%, and 50 ± 29%. NH4 removal was 9 ± 36%, 29 ± 72%, 31 ± 24%, and 45 ± 34%. BMP size, age, and location explained some of the variability. For example, small and shallow ponds and wetlands were more effective than larger, deeper ones in removing N. Despite well‐known intra‐annual variation in N fluxes, most measurements have been made over short time periods using concentrations, not flow‐weighted N fluxes. Urban N export is increasing in some areas as large storms become more frequent. Thus, accounting for the full range of BMP performance under such conditions is crucial. A select number of long‐term flux‐based BMP studies that rigorously measure rainfall, hydrology, and site conditions could improve BMP implementation. 相似文献