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In 2010, a West Nile virus (WNV) epidemic was reported in Central Macedonia, Northern Greece, with 197 neuroinvasive disease (WNND) cases in humans. The following 3 years, WNV spreads to new areas of Greece and human cases reoccurred during the transmission periods. After the initial outbreak, a WNV surveillance system using juvenile backyard chickens was established in Central Macedonia (after the 2011 outbreak) and Eastern Macedonia‐Thrace (after the 2012 outbreak). Sera were screened for the presence of antibodies against WNV using cELISA and serum neutralization test, to monitor the spread of WNV and to assess the correlation between the WNV point seroprevalence in chickens and the incidence rates of human WNND cases in the aforementioned areas. WNV seroprevalence in chickens was 10.4% (95% CI: 7–15) in Central Macedonia (2011) and 18.1% (95% CI: 14–23) in Eastern Macedonia‐Thrace (2012). Seroprevalence in chickens and incidence rates of human WNND cases in Eastern Macedonia‐Thrace were strongly positively correlated (ρ = 0.98, P = 0.005) at the regional unit level, with the incidence of WNND in humans increasing with increasing WNV point seroprevalence in chickens. In Central Macedonia, the correlation was weaker (ρ = 0.68, P = 0.20), apparently due to small number of reported human WNND cases. Another study was also conducted using juvenile backyard chickens in Central Macedonia, aiming to detect early WNV enzootic circulation, before the onset of human cases during 2011 and 2013. The first seroconverted chickens were detected about 1.5 months before the laboratory diagnosis of any human WNND cases in Central Macedonia, for both years. WNV surveillance, using juvenile backyard chickens, was reliable for the identification of areas with WNV enzootic and silent transmission, and for early warning. Timely diffusion of information to public health authorities facilitated the successful implementation of preparedness plans to protect public health.  相似文献   
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人为干扰对生物多样性的影响   总被引:2,自引:0,他引:2  
从景观破碎、保护历史、种群行为机制和种群大小4个方面讨论了人为干扰对生物多样性的影响,以期为生物多样性保护和生态环境恢复提供依据。一般人为轻度干扰会导致生物多样性提高,对比研究武夷山人为干扰甜槠林与郁闭稳定甜槠林结果表明,人为干扰甜槠林高等植物物种丰富度相对于郁闭稳定林分提高了76.32%;但人为干扰甜槠林的群落优势度却远低于郁闭林,故在演替过程中群落物种多样性的增加是生态系统对外界轻度干扰的一种适应,是恢复生态系统稳定性的一种对策,一旦干扰超过其调节能力,将难以恢复为原来的群落类型。生物在其各自进化和适应的过程中由于生态位泛化或特化,许多物种仅局限于非常小的生态位空间,这些物种一旦遭遇到景观破碎则很可能从地球上消失,如黄连和短萼黄连对阴湿条件的适应与要求,导致其濒临灭绝;另一些种类由于在群落中零星分布,如斑叶兰、羽萼悬钩子、浙江红花油茶、多种粗叶木(Lasianthus spp.)和一些紫金牛(Ardisia spp.)等,当生境缩小或受到干扰时则濒临灭绝。地史上古老的地区或自然保护历史较长的地区可能拥有更多的物种。保护历史较长的福建省南靖县和溪南亚热带雨林在1200m2面积内有128种高等植物,同一地带的鼎湖山及和溪周边地区的南亚热带雨林物种丰富度均低于此。许多植物是动物传布植物,动物物种多样性的减少影响了这些植物的传布,生境的改变也影响着植物的传布,另一些物种传布到新区域而不能萌发或完成其生活史。地方种群小于一定数量时其灭绝的可能性也增加。  相似文献   
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Influenza A viruses (IAVs) have both zoonotic and anthroponotic potential and are of public and veterinary importance. Swine are intermediate hosts and ‘mixing vessels’ for generating reassortants, progenies of which may harbour pandemic propensity. Swine handlers are at the highest risk of becoming infected with IAVs from swine but there is little information on the ecology of IAVs at the human–animal interface in Africa. We analysed and characterized nasal and throat swabs from swine and farmers respectively, for IAVs using RT‐qPCR, from swine farms in the Ashanti region, Ghana. Sera were also analysed for IAVs antibodies and serotyped using ELISA and HI assays. IAV was detected in 1.4% (n = 17/1,200) and 2.0% (n = 2/99) of swine and farmers samples, respectively. Viral subtypes H3N2 and H1N1pdm09 were found in human samples. All virus‐positive swine samples were subtyped as H1N1pdm09 phylogenetically clustering closely with H1N1pdm09 that circulated among humans during the study period. Phenotypic markers that confer sensitivity to Oseltamivir were found. Serological prevalence of IAVs in swine and farmers by ELISA was 3.2% (n = 38/1,200) and 18.2% (n = 18/99), respectively. Human H1N1pdm09 and H3N2 antibodies were found in both swine and farmers sera. Indigenous swine influenza A viruses and/or antibodies were not detected in swine or farmers samples. Majority (98%, n = 147/150) of farmers reported of not wearing surgical mask and few (4%, n = 6) reported to wear gloves when working. Most (n = 74, 87.7%) farmers reported of working on the farm when experiencing influenza‐like illness. Poor husbandry and biosafety practices of farmers could facilitate virus transmission across the human–swine interface. Farmers should be educated on the importance of good farm practices to mitigate influenza transmission at the human–animal interface.  相似文献   
5.
英汉语言中动物喻人有同亦有异,其异同集中反映在褒贬义、引申义、习语和表达方式上,应根据中西文化的差异,正确把握它们的异同。  相似文献   
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文章在简述城市污水河流概况的基础上,介绍了城市污水河流目前存在的问题。针对城市污水河流五大问题,以人水和谐为指导,本着统一规划,综合治理,按照改善环境与防洪排水相结合、维护自然生态与满足行洪排水要求相结合、生态湿地与滞洪蓄洪相结合的三大原则,给出相应的五大建议措施。城市污水河流水系实施生态治理不仅对城市发展主题具有巨大的提升和促进作用,而且将有助于改善当地的水体环境和沿河的投资环境,促进该地区社会、经济的可持续发展,实现人水和谐,为城市污水河流改善治理提供参考。  相似文献   
7.
Salmonella enterica is a common food‐borne pathogen with occasional multidrug resistance (MDR). Salmonella genomic island (SGI1) is a horizontally transmissible genomic island, containing an MDR gene cluster. All Salmonella serotypes are public health concern, although there is an additional concern associated with those that harbour SGI1. In Iran, there are no data on the presence of SGI1 variants in Salmonella isolates. The present study was conducted to identify MDR‐ and SGI1‐carrying Salmonella strains isolated from various sources and to compare their genetic relatedness between human and animal sources. In total, 242 Salmonella isolates collected from chicken, cattle, and humans from 2008 through 2014 were studied. The isolates were tested for resistance to 14 antimicrobials via the disc diffusion method. They were also tested for the presence of SGI1 variants via PCR, and genetic relatedness was evaluated based on pulsed‐field gel electrophoresis (PFGE). Resistance to at least one antimicrobial agent was observed in 132 (54%) Salmonella isolates (n = 242), while more than 40% of the isolates showed MDR. Based on PCR analysis, eight variants of SGI1, including SGI1, SGI1‐B, SGI1‐C, SGI1‐D, SGI1‐F, SGI1‐I, SGI1‐J and SGI1‐O, were found in both human and animal isolates. Statistical analysis revealed no significant difference in the prevalence of SGI1 variants between human and animal isolates (p > 0.05). Macrorestriction PFGE analysis of the isolates with the same SGI1 variant and resistance patterns revealed genetic relatedness ranging from 70% to 100% among human and animal isolates. According to our review, this is the first documentation of SGI1 in Salmonella isolates in Iran. The presence of similar SGI1 variants in both humans and animals, along with their related PFGE patterns, suggests that food‐producing animals may be a source of MDR Salmonella isolates in Iran.  相似文献   
8.
Long chain polyunsaturated fatty acids (LC-PUFAs) are important mediators in improving and maintaining human health over the total lifespan. One topic we especially focus on in this review is omega-3 LC-PUFA docosahexaenoic acid (DHA). Adequate DHA levels are essential during neurodevelopment and, in addition, beneficial in cognitive processes throughout life. We review the impact of DHA on societal relevant metabolic diseases such as cardiovascular diseases, obesity, and diabetes mellitus type 2 (T2DM). All of these are risk factors for cognitive decline and dementia in later life. DHA supplementation is associated with a reduced incidence of both stroke and atherosclerosis, lower bodyweight and decreased T2DM prevalence. These findings are discussed in the light of different stages in the human life cycle: childhood, adolescence, adulthood and in later life. From this review, it can be concluded that DHA supplementation is able to inhibit pathologies like obesity and cardiovascular disease. DHA could be a dietary protector against these metabolic diseases during a person’s entire lifespan. However, supplementation of DHA in combination with other dietary factors is also effective. The efficacy of DHA depends on its dose as well as on the duration of supplementation, sex, and age.  相似文献   
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Like humans, many companion animals experience a gradual decline in skeletal muscle mass and function during later years of life. This process, analogous to sarcopenia in humans, increases risk for morbidity and mortality. Periods of reduced activity due to injury or illness, followed by an incomplete recovery, can accelerate the loss of muscle mass and function. Emerging research from human studies suggests that moderate amounts of high-quality protein may attenuate the loss of muscle, while preventing accumulation of fat during periods of disuse. Whey protein is a consumer-friendly and readily available source of high-quality protein. It supports skeletal muscle maintenance during normal aging and may also provide anabolic support during periods of illness, injury, and recovery. Ongoing research efforts continue to refine our understanding of how protein quality, quantity, and meal timing can be optimized to support retention of muscle mass and function during aging. Priority research areas include supplementation with high-quality protein during illness/injury to stimulate anabolism by targeting molecular mechanisms that regulate skeletal muscle metabolism.  相似文献   
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