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Alya Limayem Elizabeth M. Martin 《Journal of environmental science and health. Part. B》2013,48(2):124-133
Antibiotics are frequently used in agricultural systems to promote livestock health and to control bacterial contaminants. Given the upsurge of the resistant fecal indicator bacteria (FIB) in the surface waters, a novel statistical method namely, microbial risk assessment (MRA) was performed, to evaluate the probability of infection by resistant FIB on populations exposed to recreational waters. Diarrheagenic Escherichia coli, except E. coli O157:H7, were selected for their prevalence in aquatic ecosystem. A comparative study between a typical E. coli pathway and a case scenario aggravated by antibiotic use has been performed via Crystal Ball® software in an effort to analyze a set of available inputs provided by the US institutions including E. coli concentrations in US Great Lakes through using random sampling and probability distributions. Results from forecasting a possible worst-case scenario dose-response, accounted for an approximate 50% chance for 20% of the exposed human populations to be infected by recreational water in the U.S. However, in a typical scenario, there is a 50% chance of infection for only 1% of the exposed human populations. The uncertain variable, E. coli concentration accounted for approximately 92.1% in a typical scenario as the major contributing factor of the dose-response model. Resistant FIB in recreational waters that are exacerbated by a low dose of antibiotic pollutants would increase the adverse health effects in exposed human populations by 10 fold. 相似文献
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Ecology of Chytridiomycosis in Rainforest Stream Frog Assemblages of Tropical Queensland 总被引:5,自引:0,他引:5
Abstract: In the wet tropics of Queensland, Australia, eight species of stream-dwelling frogs have experienced population declines. Some declines were associated with an emerging infectious disease of amphibians (chytridiomycosis) caused by the fungus Batrachochytrium dendrobatidis. We examined the spatial and temporal pattern of infection prevalence in a sample of frog populations. Infected adults and tadpoles of all species were found, and infections occurred at every site. Infection prevalence varied among species and was always < 10.0% in adults but ranged from 0.75 to 76.0% in tadpoles. In this system tadpoles and adults of some species may act as disease reservoirs, experiencing avirulent infections, whereas other hosts (declining species) experience virulent infections. Infection prevalence was higher during the cool, dry winter season (May to September) and at high elevations (600–800 m), suggesting regulation by environmental conditions, including temperature and precipitation. We found no relationships between infection prevalence and mean body condition, fluctuating asymmetry of hind limbs, population density, or the presence of metamorphosing tadpoles and juvenile frogs. Although it is not certain whether chytridiomycosis was responsible for past frog population declines in the wet tropics of Queensland, the pathogen is now endemic. Our data indicate that at the landscape level, environmental conditions have strong effects on host-pathogen dynamics. These effects interact with species-specific behavior or immune function and may be important underlying determinants of chytridiomycosis epizootics and emergence. 相似文献
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R. Achiron MD O. Pinhas-Hamiel S. Lipitz Z. Heiman B. Reichman S. Mashiach 《黑龙江环境通报》1994,14(7):523-526
Cytomegalovirus is the most common cause of congenital viral infection. In utero infection is usually suspected in patients with growth-retarded fetuses or when maternal illness precipitates serological investigations. A case is presented where routine ultrasound examination at 30 weeks' gestation in an asymptomatic patient demonstrated mild fetal ventriculomegaly. Transvaginal ultrasound enabled the visualization of intraventricular adhesions and small periventricular cysts. The suspected diagnosis of in utero cytomegalovirus infection was confirmed by the presence of IgM antibodies in fetal blood and subsequently by isolation of the virus from the infant's urine. The presence of mild fetal ventriculomegaly should prompt transvaginal brain imaging. 相似文献
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《环境科学学报(英文版)》2023,35(7):128-138
Bacterial infections have become a great threat to public health in recent years. A primary lysozyme is a natural antimicrobial protein; however, its widespread application is limited by its instability. Here, we present a poly (N-isopropylacrylamide) hydrogel inverse opal particle (PHIOP) as a microcarrier of lysozyme to prolong and enhance the efficiency against bacteria. This PHIOP-based lysozyme (PHIOP-Lys) formulation is temperature-responsive and exhibits long-term sustained release of lysozyme for up to 16 days. It shows a potent antibacterial effect toward both Escherichia coli and Staphylococcus aureus, which is even higher than that of free lysozyme in solution at the same concentration. PHIOPs-Lys were demonstrated to effectively inhibit bacterial infections and enhance wound healing in a full-thickness skin wound rat model. This study provides a novel pathway for prolonging the enzymatic activity and antibacterial effects of lysozyme. 相似文献
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医院室内空气质量直接影响着院内每个人的身体健康,对医院空气进行定期监测是预防和控制医院感染的重要措施。对中国南部沿海某城市10所医院门诊空气质量状况进行了调查。结果发现,所调查门诊中室内二氧化碳、一氧化碳和可吸入颗粒物浓度均达至良好级别。但是,分别有两家门诊的室内温度和相对湿度未能达到良好级别,而且有8家门诊的空气中细菌总数未能达到良好级别。因此,本文建议相关医院采取相应的措施加强对门诊室内空气质量(尤其是细菌数量)的控制。 相似文献
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