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1.
Pastoret Paul-Pierre   《Vaccine》2009,27(46):6435
Vaccination, when available, is undoubtedly the most cost-effective means of preventing and controlling, and even eradicating, infectious diseases. In recent years vaccination has also been used for other purposes in animal health, production and welfare, e.g. immunocastration.Vaccination of animals serves many different purposes, such as controlling animal infections and infestations, thus improving animal health and welfare; controlling anthropozoonoses and food poisoning in humans, thereby protecting public health; solving problems associated with antibiotic and anthelmintic resistance; helping to leave food-producing animals free of chemical residues; protecting the environment and biodiversity and ensuring animal farming sustainability. The problem is nevertheless more complex when facing emerging or re-emerging infections particularly zoonotic ones.  相似文献   
2.
The genetic diversity of two samples of Cestoda (Bothriocephalus funiculus, Renaud and Gabrion, 1984) parasitizing two sympatric teleostean species was assessed using random amplified polymorphic DNA (RAPD). A total of 72Bothriocephalus were analyzed individually, and electrophoretic analysis of the amplification products of 65 primers among the 68 tested revealed monomorphic patterns, reflecting the close genetic relatedness within and between the parasites of the two samples. However, 3 primers showed polymorphic patterns at 6 RAPD sites. Analysis of the distribution of these genomic fragments, assuming random mating, showed strong linkage disequilibria (only 8 genetic combinations were observed among the 32 expected). Two genetic entities displaying a high degree of host specificity were evidence within our two samples ofB. funiculus. This powerful molecular technique can be used as a diagnostic tool in studies concerning the biodiversity of related genetic entities and could have broad applications in parasitology.  相似文献   
3.
A total of 156 commercial canola seed samples were collected from two growing seasons and tested for oil and protein content, glucosinolate concentration and kernel weight. Extracted oil samples were tested for the bioactive compounds: β-carotene (mean = 2.03 mg/kg), lutein (64.7), α-tocopherol (263), γ-tocopherol (378) and δ-tocopherol (8.94). A subset of 52 oil samples were analyzed for fatty acid profile (FAP) and oxidative stability. Canola cultivar was found to be the dominant influence on many traits, particularly carotenoids and tocopherols, indicating potential breeding opportunities. Previously unreported significant correlations were discovered between the two major carotenoids, lutein and β-carotene. Additionally, significant (p < 0.01) negative correlations existed between oil content and: β-carotene (r = −0.33), lutein (r = −0.23), α-tocopherol (r = −0.49), γ-tocopherol (r = −0.22), and δ-tocopherol (r = −0.30). Polyunsaturated fatty acid content was significantly (p < 0.01) positively correlated with carotenoid (r = 0.48) and tocopherol (r = 0.60) concentrations. Oxidative stability showed a weak negative correlation with total tocopherols (r = −0.38, p = 0.01) likely due to the over-riding influence of fatty acid profile on oxidative stability, indicating tocopherols may be more influential from a nutritional perspective rather than oil functionality.  相似文献   
4.
Natural environments may be important for subjective wellbeing, yet evidence is sparse and measures of nature are unspecific. We used linear regression models to investigate the relationship between greenness, biodiversity and blue space and subjective wellbeing in 4,912 adults living in metropolitan Melbourne, Australia. Greenness (overall, private and public) and biodiversity associated with subjective wellbeing. In particular, we highlight the importance of the private greenness-subjective wellbeing association. Our work has implications for urban policy and planning in the context of increased urban densification.  相似文献   
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6.
目的 探索健康人、结核分枝杆菌潜伏感染者和活动性肺结核患者痰液菌群的差异。方法 搜集2016年11月至2017年12月深圳市慢性病防治中心健康体检者53名作为A组,登记确诊的结核分枝杆菌潜伏感染(LTBI)者41例作为B组,初治活动性肺结核患者54例作为C组。研究对象均于清晨空腹状态下收集下呼吸道痰液样本(以干酪痰和黏液痰为佳)3~5ml,共148份。痰液样本提取总DNA,对16S rRNA V4~V5区基因进行高通量测序,并对测序结果进行生物信息学分析。结果 通过对148份痰液样本进行高通量测序分析,获得有效序列14136502.0条,获得操作分类单元(operational taxonomic units,OTU)21712.00个。Alpha多样性分析显示,A组Pielou_e指数为0.85(0.82,0.88),明显高于C组[0.83(0.78,0.86)],差异有统计学意义(H=4.462,P=0.035)。Beta多样性分析发现,三组人群痰液菌群组成存在差异(H=2.027,P=0.002)。菌群组间差异物种分析发现,三组人群在3个门(厚壁菌门、梭杆菌门、螺旋体门)、3个纲(黄杆菌纲、梭杆菌纲、螺旋体纲)、5个目(黄杆菌目、乳杆菌目、梭杆菌目、伯克霍尔德菌目、螺旋体目)、6个科(紫单胞菌科、黄杆菌科、梭杆菌科、纤毛菌科、伯克菌科、螺旋体科)、5个属(二氧化碳噬纤维菌属、卟啉单胞菌属、梭杆菌属、纤毛菌属、密螺旋体属)和2个种(NanceiensisParvula)水平上均存在差异;其中,C组中伯克霍尔德菌目(Burkholderiales)[0.01(0.00,0.02)]和伯克菌科(Burkholderiaceae)[0.01(0.00,0.01)]的丰富度较A组[丰富度分别为0.00(0.00,0.01)和0.00(0.00,0.00)]和B组[丰富度分别为0.00(0.00,0.01)和0.00(0.00,0.00)]明显增加,差异均有统计学意义(C组与A组比较:H值分别为9.733和4.799,P值分别为0.002和0.028;C组与B组比较:H值分别为12.134和8.152,P值均<0.01)。结论 结核分枝杆菌感染未改变人痰液菌群的丰富度,但造成菌群结构组成上产生差异。  相似文献   
7.
Potatoes are part of the staple food of Andean populations. Although there are more than 200 Andean potato varieties, only a few are cultivated at present, which endangers the biodiversity of the region. The objective of this paper was to characterize seven varieties of Andean potatoes (Collareja, Runa, Churqueña, Señorita, Imilla Colorada, Imilla Negra and Revolución) and to determine their phenotypic, functional and nutritional properties. The different varieties of Andean potatoes show differences in their agronomic properties, such as area of production and altitude yield per hectare, pest resistance and sowing and harvesting seasons. They are adapted to different altitudes, which influence their agronomic characteristics. Yield varies between 8000 and 18,000 kg/ha according to the variety. They present a diversity of forms, sizes and colors. The energy content ranges from 315 to 424 kJ/100 g, with these values being higher than those of the reference variety (239 kJ/100 g). Vitamin C content ranges from 10.5 mg/100 g found in Revolución varieties to 15.6 mg/100 g in Collareja potatoes; the vitamin C content in Spunta lies within this range (13.3 mg/100 g of potato). Increased knowledge of the nutritional, agronomic and functional properties of Andean potato varieties will contribute to the preservation of a biodiversity that is part of Argentina's regional heritage.  相似文献   
8.
罗布泊地区沙生植物根际放线菌多样性及生物活性的研究   总被引:2,自引:0,他引:2  
目的研究罗布泊地区沙生植物根际放线菌多样性及其生物活性,以期发现新药用微生物资源。方法采用2种分离方法,6种分离培养基,从两种沙生植物24份根际土样中分离放线菌;对其中131株放线菌发酵液及乙酸乙酯提取液采用抗菌、杀线虫模型进行活性筛选,并根据活性测定结果结合菌株形态特征对其中66株进行16S rRNA基因序列分析。结果共分离到放线菌154株,53株在其中一个或两个活性筛选模型中都显示为阳性,总阳性率为40.46%,16S rRNA基因序列分析表明这66株放线菌分布在12个属,除了优势菌链霉菌(Streptomyces)外,还发现了拟诺卡氏菌属(Nocardiopsis),拟无枝酸菌属(Amycolatopsis),疣孢菌属(Verrucosispore),喜冷杆菌属(Cryobacterium),异壁放线菌属(Actinoalloteichus),假诺卡氏菌属(Pseudonocardia),普氏菌属(Prauserella),链单孢菌属(Streptomonospora),贫养杆菌属(Modestobacter),放线产孢菌属(Actinomycetospora),芽生球菌属(Blastococcus)等稀有放线菌属,菌株CA15-2与GenBank数据库中最近种Nocardiopsis nikkonensis YU1183-22T(GenBank登录号:AB491226)的相似性约为94%,可能为潜在的新属或新种。结论罗布泊地区沙生植物根际存在较为丰富的放线菌资源并能产生多种活性次级代谢产物,值得进一步的研究。  相似文献   
9.
Nutrients, bioactive non-nutrients and anti-nutrients in potatoes   总被引:2,自引:0,他引:2  
Globally, potatoes account for only about 2% of the food energy supply, yet they are the predominant staple for many countries. In developed countries, potatoes account for 540 kJ (130 kcal) per person per day, while in developing countries, it is only 170 kJ (42 kcal) per person per day. In addition to energy, which is derived almost entirely from their carbohydrate content, many varieties of potatoes contribute nutritionally important amounts of dietary fibre (up to 3.3%), ascorbic acid (up to 42 mg/100 g), potassium (up to 693.8 mg/100 g), total carotenoids (up to 2700 mcg/100 g), and antioxidant phenols such as chlorogenic acid (up to 1570 mcg/100 g) and its polymers, and anti-nutrients such as α-solanine (0.001–47.2 mg/100 g); and lesser amounts of protein (0.85–4.2%), amino acids, other minerals and vitamins, and other beneficial and harmful bioactive components. Nutrient content depends on a number of factors, with variety being among the most important. Potato biodiversity is vast, with more than 4000 known varieties. Most belong to the species Solanum tuberosum, but another 10 species are cultivated and 200 wild species have been identified. Modern agricultural practices and climate change are contributing to the loss of potato biodiversity, and thus the loss of the genes coding for nutrient biosynthetic pathways. Knowledge of differences in nutrient composition of potatoes related to their genetic diversity will help guide strategies that may contribute to reducing biodiversity loss and improving food and nutrition security.  相似文献   
10.
蚊蝇等病媒生物不仅可以通过叮咬或污染食物而影响和危害人类的正常生活,还可以通过多种途径传播一系列的重要传染病。到目前为止,国内对蚊蝇等病媒生物监测的分析方法主要有卡方检验、月频数(密度)图以及立体构成图等,为制定科学的病媒生物防控策略提供了可靠的数据支持;然而对于蚊蝇等病媒生物监测的分析方法仍需进一步研究和探讨。现就圆形分布法及生物多样性指标在蚊蝇等病媒生物监测中的应用进行综述,希望能为病媒生物的防控提供更多的科学数据。  相似文献   
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