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Lower urinary tract obstruction has a significant impact on neonatal and child health. Pulmonary hyperplasia and renal impairment could be direct or indirect consequences of this condition leading to significant morbidity and mortality. Evaluation of fetuses with suspected lower urinary tract obstruction is performed not only to confirm the diagnosis but also to assess renal prognosis. Ultrasound examination and urinary analysis aid in the evaluation of these fetuses. The decision to perform fetal intervention in these cases is a difficult one. Vesico‒amniotic fetal shunting, open fetal surgery and more recently endoscopic fetal surgery for this condition are available as possible modalities of fetal intervention. Case selection for fetal intervention is extremely important in order to both avoid unnecessary intervention in those unlikely to survive, and also to avoid procedure related complications in fetuses likely to do well without intervention. Vesico‒amniotic shunting has the advantage of bypassing the obstruction, however it is often associated with complications. Open fetal surgery is not usually recommended because of the complications and high fetal loss rate. Endoscopic surgery to visualise and treat the cause of lower urinary tract obstruction has been tried. Fetal endoscopic surgery is in its infancy and endoscopic procedures are limited to a few groups. This current review addresses evaluation, case selection and therapeutic options for lower urinary tract obstruction in utero. It also discusses the limited data against which the efficacy of the various options can be assessed. The current state of fetal intervention is detailed in the present review. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Water governance has emerged as perhaps the most important topic of the international water community in the 21st century, and achieving “good” water governance is now a focus of both policy discourse and innumerable development projects. Somewhat surprisingly in light of this attention, there is widespread confusion about the meaning of the term “water governance”. This paper reviews the history of the term's use and misuse to reveal how the concept is frequently inflated to include issues that go well beyond governance. Further, it highlights how calls to improve water governance often espouse predetermined goals that should instead be the very function of water governance to define. To help overcome this confusion, the paper suggests a more refined definition of water governance and related qualities of good water governance that are consistent with broader notions of the concepts. In light of the substantial resources allocated in its name, this paper's findings show there is significant potential to strengthen efforts at improving water governance. 相似文献
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Selenium status in soils of northern districts of India 总被引:1,自引:0,他引:1
The HG-AAS technique was used to estimate the soil selenium status of the agricultural lands of northern parts of India. The drier lands where lesser rains were received or where less irrigation water was available in Rajasthan and southern parts of the Haryana states had above normal soil selenium levels. These soils were also found to be alkaline. Punjab, Himachal Pradesh and northern parts of the Haryana states had normal levels of selenium in their soils, except with slightly lower selenium levels in a few areas that were affected by floods along the river Yamuna. The results were also confirmed using the ICP-OES technique. 相似文献
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Thawale P Ghosh T Kumar Singh S Singh S Kulkarni A 《Environmental monitoring and assessment》2012,184(4):2575-2591
Feasibility of an irrigation project is evaluated by two criteria viz., reservoir capacity to irrigate its command area and
economic returns by incremental crop production versus capital investment for dam construction. The annual water requirement
of different crops in the command area is estimated and compared with the availability of water from the dam for irrigation
purpose. The annual crop water requirement is estimated as the sum of evapotranspiration for crops and transmission and other
losses. Evapotranspiration is estimated by modified Penman formula. Economics of crop production is analyzed by first estimating
the monetary value of existing crop production under current rain fed conditions and then estimating the incremental production
of irrigated command area for the proposed crop pattern. The proposed cropping pattern is prepared so as to maximize the benefit
of crop production and fodder requirement while maintaining a better crop rotation to improve and maintain physical, chemical,
and biological conditions of the soil. The dam is to be used for irrigation and water supply only. Command area served by
this reservoir will be 76,500 ha. The existing annual agricultural return is Rs. 2995.56 lakhs and with the proposed irrigation
scheme, it is estimated as Rs. 1,77,91.90 lakhs. The incremental annual return would be Rs. 1,47,96.35 lakhs i.e., 642.68%
increase in annual return. 相似文献
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Sanjiv Kumar Venkatesh Merwade 《Journal of the American Water Resources Association》2009,45(5):1179-1196
Abstract: Impact of watershed subdivision and soil data resolution on Soil Water Assessment Tool (SWAT) model calibration and parameter uncertainty is investigated by creating 24 different watershed model configurations for two study areas in northern Indiana. SWAT autocalibration tool is used to calibrate 14 parameters for simulating seven years of daily streamflow records. Calibrated parameter sets are found to be different for all 24 watershed configurations, however in terms of calibrated model output, their effect is minimal. In some cases, autocalibration is followed by manual calibration to correct for low flows, which were underestimated during autocalibration. In addition to normal validation using four years of streamflow data for each calibrated parameter set, cross‐validation (using a calibrated parameter set from one model configuration to validate observations using another configuration) is performed to investigate the effect of different model configurations on streamflow prediction. Results show that streamflow output during cross‐validation is not affected, thus highlighting the non‐unique nature of calibrated parameters in hydrologic modeling. Finally, parameter uncertainty is investigated by extracting good parameter sets during the autocalibration process. Parameter uncertainty analysis suggests that significant parameters show very narrow range of uncertainty across different watershed configurations compared with nonsignificant parameters. Results from recalibration of some configurations using only six significant parameters were comparable to that from calibration using 14 parameters, suggesting that including fewer significant parameters could reduce the uncertainty arising from model parameters, and also expedite the calibration process. 相似文献
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Selenium status in food grains of northern districts of India 总被引:2,自引:0,他引:2
The selenium status in the food grains of the agricultural lands of northern parts of India was estimated by using the HG-AAS technique. The areas where lesser rains were received or less irrigation water was available in northern Indian states viz. Rajasthan and southern parts of the Haryana had higher selenium levels in food grains. Punjab, Himachal Pradesh and northern parts of the Haryana states had normal levels of selenium in their food grains, except for slightly lower selenium levels in a few areas that were affected by floods along the river Yamuna. 相似文献
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Ajay Kumar Meena Parveen Bansal Sanjiv Kumar M. M. Rao V. K. Garg 《Environmental monitoring and assessment》2010,170(1-4):657-660
Popularity of herbal drugs is increasing all over the world because of lesser side effects as compared to synthetic drugs besides it cost effectiveness and easy availability to poor people particularly in developing countries. Keeping in view the increased market demand of herbal drugs, it is essential to ensure their chemical quality prior to use. Raw drugs and herbs are usually collected from different places, which might be contaminated with various contaminants. It is pertinent to estimate the levels of heavy metals and other micronutrients, which could be affected by their presence in the surrounding environments. Heavy metals are known to pose a potential threat to terrestrial and aquatic biota. Keeping this in view, samples of ten plants or plant parts used in drug making were collected from local markets of Punjab for heavy metal and micronutrient estimation. It was found that the samples were contaminated having cadmium, lead, chromium, iron, manganese, and zinc. The highest mean level of cadmium (23.1 μg/kg) was found in Haritaki sample. Chromium concentration of the plant samples ranged between 7.25 and 1.34 μg/kg with the highest values was in Daruharidra and lowest in Pippali. The levels of these heavy metals were within permissible limits 相似文献
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The Isipingo lagoon and estuary, situated to the south of the Durban metropolitan area, on the east coast of South Africa,
has been subjected to intense environmental degradation. Historical events, such as the building of a major airport and the
development of an industrial township, have contributed to the reduction in water flow from 102 × 106 m3/yr to 3 × 106m3/yr between 1952 and 1969. Current environmental issues such as water quality, litter, noise, air pollution, and solid waste
dumping are described. A rehabilitation and management program that seeks to address these issues is proposed. The main objectives
of this program are: the improvement of the water flow, the improvement of the water quality, and the curtailment of the destruction
of littoral zone elements. The rehabilitation proposal is summarized by means of a flow chart, which lists short-, medium-,
and long-term actions and identifies parties and/or organizations responsible for implementing the actions. A two-tier management
structure is proposed, with the first level comprising an environmental monitoring committee, consisting of organizations
with scientific expertise who would function in a watchdog capacity, monitoring restoration efforts and intervening where
actions are contrary to the objectives of the rehabilitation program. The second level would consist of an estuarine management
committee, which would be responsible for evaluating the restoration program and modifying objectives where necessary. 相似文献