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131.

Objective

To ascertain the perinatal outcomes for an apparently isolated exomphalos detected by prenatal ultrasound.

Method

Our dataset captures cases from 614 321 births in the Wessex region of England and the Channel Isles on all cases of pre- or postnatally diagnosed exomphalos from 1994 to 2015. Ascertainment was >95%.

Results

Three hundred and thirty five cases were reported to the register: 28 (8%) were not detected prenatally, 18 (6%) had already died in utero, 169 (55%) cases were found to have additional anomalies on first tertiary ultrasound scan and one case was lost to follow-up. Therefore 119 (39%) cases had an apparently isolated exomphalos. Of the 119 cases with only an exomphalos detected on first tertiary ultrasound scan, 25 (21%) had a chromosome abnormality. Of those with a normal or untested karyotype, 61% were confirmed to be an isolated anomaly after birth, 13% had an additional heart abnormality, 9% had Beckwith-Wiedemann syndrome and 11% had additional problems diagnosed postnatally.

Conclusion

Our large population-based dataset with an average of 1 year's postnatal follow-up suggests that more than one-third of apparently isolated prenatal cases of exomphalos will have an additional finding detected after birth. These data should help assist clinicians in their prenatal counseling.
  相似文献   
132.
Title II of the 1972 “Clean Water Act” provided for a potentially massive federal construction grant program for the construction of publicly owned wastewater treatment plants. Part of this subsidy accrues to municipalities and the remainder to industry. The regulations for these federal grants are somewhat perplexing and it is not obvious who will benefit and by how much. The objective of this article is to quantify the subsidies received by municipalities and industry and estimate the effect on the distribution of income under certain assumptions. It is concluded that these federal construction grants are likely to redistribute income from the middle-income classes to primarily the very rich.  相似文献   
133.
The amount of off-site pesticide spray drift from aerial and ground applications was determined at 26 sites across Ontario. These were conducted along transects, parallel and at right angles to the flight path during aerial spray applications and at right angles to the direction of ground spray applications. All sites monitored were where commercial spray operations were in progress. The aerial applications involved both fixed wing aircraft and helicopters and the ground applications involved concentrated air-blast machines and high and low pressure boom sprayers. Deposits of spray drift outside the target area were common to all spray equipment monitored. All except low-pressure boom spraying equipment resulted in measurable spray drift to 80 m off-target with appreciable deposits up to 30–40 m. In a forest spray operation, where insecticide release was the highest, measurable residues were found up to 120 m off-target. The amount of chemical deposited off-target varied with the chemical, the climatical conditions and the equipment used. With a low-pressure boom sprayer, serious drift was confined to 9 m off-target and measurable residues to 15 m.  相似文献   
134.
Experimental studies were performed under controlled environmental conditions to determine the deposition and subsequent allocation of carbon-14, following a short-term fumigation of major British crops with 14CO2. The deposition velocities varied between 0.075 and 1.32 cm3 g-1 s-1 and 0.0008 and 0.157 cm s-1 on weight and area bases, respectively. The primary sites of deposition were leaves, although other organs, e.g. ears and pods, were increasingly important as the crops developed. Activity was allocated post-deposition to those crop components actively growing at the time of deposition. The allocation was generally completed 24 h after fumigation, the exceptions to this being those crops where reproductive organs developed after the fumigation. A single exponential function was the best fit for the loss of activity from the crops. The data are discussed in the context of modelling carbon-14 contamination of crops following radioactive discharges.  相似文献   
135.
Some natural resource investments are unique from a capital theory point of view because they do not create a new income stream, but rather alter the rate of change of an existing stream of income or social benefit. The marginal conditions for such investments are explored and possible incentive methods are examined for the case of soil conservation expenditures.  相似文献   
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ABSTRACT: A loafing or sacrifice lot is an area located outside of the free stall barn, where a dairy herd spends several hours per day. Sacrifice lots are usually denuded of vegetation and have high concentrations of manure and urine that can contribute significant amounts of sediment, nutrients, and pathogens to nearby surface waters. In this study, stream water quality impacted by direct runoff from a sacrifice lot was monitored for a period of 20 months. Ambient stream water quality was monitored by grab sampling upstream and downstream of the sacrifice lot. During runoff events, stream water quality downstream of the sacrifice lot was monitored with an automatic sampler. Laboratory analyses were conducted for total suspended solids and nutrients (nitrogen and phosphorus compounds). A grass filter strip (GFS) was installed as a buffer downslope of the sacrifice lot 10 months into the study period. The impact of the buffer strip on the standardized pollutant concentrations and loads was evaluated using the non-parametric Wilcoxon test. The Wilcoxon test indicated that there was no significant difference (α= 0.05) in the standardized yield of sediment and dissolved pollutants before and after the GFS installation, except for phosphate-phosphorus and filtered total phosphorus concentrations, and sediment-bound total phosphorus and total kjeldahl nitrogen loads that decreased significantly. However, load decrease could have been partially caused by the smaller rainfall volumes after the GFS installation as compared to the existing condition.  相似文献   
139.
Testosterone was measured in maternal plasma (58 samples), amniotic fluid (71 samples) and fetal plasma (55 samples) in 79 patients between 15 and 23 weeks' gestation. Maternal plasma testosterone levels were unrelated to fetal sex. Amniotic fluid testosterone was significantly higher in male than female fetuses but did not reliably predict fetal sex. A correct diagnosis of fetal sex was made by testosterone assay of pure fetal plasma in 39 out of 40 males and in 15 out of 15 females using 1.70 nmol/1 as the cut-off value. This investigation is not the method of choice for routine fetal sexing but may be of value in fetuses suspected of having certain endocrine disorders.  相似文献   
140.
Gas-cooled nuclear power plants in the UK release sulphur-35 during their routine operation. The gas is in the form of COS which can be readily assimilated by vegetation. It is therefore necessary to be able to model the uptake of such releases in order to quantify any potential contamination of the food chain. To develop such models experimental data are required. A series of experiments was undertaken to determine the rate of deposition, the partition and subsequent loss of sulphur-35 in crops exposed to CO(35)S. The mass normalised deposition rate was similar for the range of crops tested, while the partition of the (35)S paralleled the growth of crop components. There was no significant loss of radioactivity other than that expected from radioactive decay.  相似文献   
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