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排序方式: 共有250条查询结果,搜索用时 8 毫秒
211.
212.
Because a vascular aetiology has been suggested for the limb and oromandibular defects described after chorionic villus sampling (CVS), to determine whether transabdominal (TA) CVS causes noticeable changes in umbilical artery velocity waveforms in first-trimester pregnancies, the pulsatility index (PI) of the umbilical artery was evaluated before and after TA-CVS in 175 pregnancies sampled between 10·0 and 13·0 weeks' gestation. In 139 uncomplicated pregnancies, the mean PI values (with 95 per cent confidence interval) were before TA-CVS 2·751 (2·692–2·809), after 10 min 2·723 (2·697–2·809), and after 1 h 2·781 (2·722–2·840). There were no significant changes in PI relative to the CVS procedure either in pregnancies with an abnormal result or in those ending in spontaneous abortion. Our data do not support any statistically significant change in umbilical artery PI relative to TA-CVS in first-trimester pregnancies. This procedure, despite its invasive character, does not appear to affect the feto-placental circulation. 相似文献
213.
Debra E Huffman Angela L Gennaccaro Tracy L Berg Glenda Batzer Giovanni Widmer 《Water environment research》2006,78(12):2297-2302
The presence of infectious protozoan pathogens in reclaimed water may present an unacceptable health risk. This study was designed similar to a study reported by Garcia et al. (2002), which detected no infectious Giardia cysts in the final effluent of a tertiary treatment facility as determined by animal infectivity (dose 1000 cysts/gerbil). This study also included evaluation of Cryptosporidium oocyst infectivity. Infectious Giardia cysts were detected in the final effluent with 1 gerbil out of 3 inoculated with 250 cysts from reclaimed water showing signs of infection 15 days postinoculation. None of the Cryptosporidium oocysts concentrated from the reclaimed water samples appeared to be infectious. 相似文献
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215.
Sicily is the largest island in the Mediterranean, and tourism represents the most important income in the regional budget. This is due to a mild climate, to its considerable archaeological and cultural heritage, but above all to the beaches, which host visitors for most of the year. Nevertheless, Sicily has no official Integrated Coastal Zone Management (ICZM) policy and also lacks an overall plan for coastal protection. In 2000, however, driven by the EU, a process of selection of projects based on objective parameters was initiated. Not all of these projects have had the expected results and some are yet to be completed. One of these is Giardini Naxos, Taormina beach, one of the main tourist resorts in Sicily. There, due both to the incorrect position of the port structure and to the rapidly increasing coastal urbanization (second homes, hotels and waterfront), a process of coastal erosion has started, the beach has disappeared, and the promenade has been damaged. To rebuild the shore in order to protect the structures behind it and to restore the coast for beach goers, a submerged barrier (like a reef) was designed to protect an artificial beach replenishment using local and remote sands, mined from the continental platform bottom and compatible both in terms of composition and grain size. Even though the results were excellent during the first stages of the project, towards the end, financial support disappeared and the funds were allocated to other projects. This experience in Giardini Naxos illustrates the ineffectiveness of defensive action in the absence of coastal planning that takes into account the sustainability of interventions on a regional basis both from a structural and an economic standpoint. 相似文献
216.
Lonati G Ozgen S Ripamonti G Cernuschi S Giugliano M 《Journal of the Air & Waste Management Association (1995)》2011,61(11):1273-1280
Measurement campaigns for airborne particles along a pedestrian route in the city center of Milan were performed by means of a portable instrument consisting of an optical particle counter and a global positioning system (GPS) signal receiver. Based on the size-resolved particle number concentration data and on proper density factors experimentally determined for Milan urban area, the mass concentrations were calculated in terms of particulate matter with aerodynamic diameters < or =10 microm (PM10), < or =2.5 pm (PM2.5), and < or =1 microm (PM1). Besides directly measuring the personal exposure to PM throughout the route, the measurement campaigns pointed out small spatial and temporal variations of the concentration ranges in the different urban microenvironments visited along the route as well as very peculiar features of the particles levels in the underground subway. These findings suggested that the personal exposure of pedestrians in the city center could be estimated by simply taking into account the exposure at the open air and in the subway. The comparison between measured and calculated exposures according to the microenvironment-based estimation results in reasonable accordance, even though the estimations tend to slightly underestimate (12%) the actual measured exposure. 相似文献
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218.
Lariophagus distinguendus (Hymenoptera: Pteromalidae) is a generalist solitary ectoparasitoid parasitising immature stages of at least 11 foodstuff beetles from five families, including species developing in seeds of Poaceae and Fabaceae. In this study, we tested the role of visual and olfactory stimuli affecting L. distinguendus host location in the trophic context of Stegobium paniceum (Coleoptera: Anobiidae) infesting chickpeas, Cicer arietinum (Fabales: Fabaceae). When either visual plus olfactory cues or olfactory cues alone were provided, S. paniceum-infested chickpeas were more attractive than uninfested chickpeas to naïve L. distinguendus females. Larval faeces of S. paniceum also evoked strong attraction to female wasps. Uninfested chickpeas covered with host faeces were preferred over uninfested ones without faeces, while infested chickpeas were as attractive as healthy chickpeas plus host faeces. Overall, results demonstrated that L. distinguendus females orient their host-seeking decisions mainly on the basis of faeces-borne olfactory stimuli. Further research is on-going to characterise the volatiles from S. paniceum larval faeces to evaluate their attractiveness towards L. distinguendus females. 相似文献
219.
Matteo Vizzarri Ugo Chiavetta Giovanni Santopuoli Daniela Tonti Marco Marchetti 《Journal of Environmental Planning and Management》2015,58(8):1454-1478
In last decades, numerous efforts have been carried out by the scientific community to assess the multifunctional role of forests in supporting the forest decision-making processes. Recently developed in Italy, the Forest Landscape Management Planning seems to be the most suitable tool to maintain the sustainability balance between forests and local populations. This research identifies and maps different forest ecosystem functions in a mountain Natura2000 Network site by performing a spatial estimation of forest inventory parameters, and implementing a multi-criteria and multi-level approach. Final results on mapping of forest functions show acceptable values of classification accuracy. 相似文献