首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   4篇
  免费   0篇
  2篇
畜牧兽医   1篇
园艺   1篇
  2021年   1篇
  2017年   1篇
  2013年   1篇
  1996年   1篇
排序方式: 共有4条查询结果,搜索用时 15 毫秒
1
1.
2.
Genetic Resources and Crop Evolution - The loss of agrobiodiversity is a topic of global impact. On a local scale, Lombardy, in the Alpine macro-Region, has lost more than 78% of its plant...  相似文献   
3.
From November 1990 to June 1991, 2273 Dirofilaria immitis were collected from 175 stray dogs euthanized in the province of Padua. The breed, sex, age and weight of each animal were noted. The worms were counted, sexed, differentiated as adults or fifth-stage larvae and weighed, and their length was measured.The host-parasite relationship in this epidemiological situation was characterized by a high prevalence (67%) together with a low intensity (19) and abundance (13). The frequency distribution of the parasites in the population of dogs followed a negative binomial pattern (K+0.3177), showing a good, stable host-parasite relationship. The major risk of infection was in late July and August, some new infections being established in October and, maybe, in November. The majority of dogs that acquired new infections were young animals, probably because of an immune response in older dogs. However, the prevalences increased (p<0.01) in dogs from 1 to 5 years old, in shepherd and hunting dogs compared to the other breeds, and in large as opposed to small dogs.Microfilaraemia (range 1–1 883 000/ml) correlated, as a trend, with the number of adult filariae, which also correlated with the age and the weight of the dogs (p0.01). No significant correlations were found between the length or weight of the adult filariae and the data from dogs.Abbreviations EDTA ethylenediaminetetracetic acid - L3, L4, L5 third-, fourth- and fifth-stage larvae respectively  相似文献   
4.
A key policy objective of many European Governments and their forestry departments is socially inclusive use of woodlands as use is a pre-requisite to enjoying many of the benefits afforded by woodland. However, access to woodlands is unequally distributed across British society and research suggests disconnect between the facilities provided and their suitability-for-use, given the wide range of reasons for visiting woodland. This research sought to inform woodland management and complement research into barriers to accessing woodland by investigating whether the design and provision of core access facilities may preclude certain user-groups. The research was carried out on the public forest estate of England; although the results are applicable to any woodland where public access is encouraged. The generic findings are applicable also to other greenspace types. Preferences in design were strongly influenced by the instrumentality (functionality) and aesthetic of an item – whether it was in-keeping with the woodland setting. Facility provision and upkeep are also important to woodland users. The study suggests that small changes in facility provision, including greater emphasis on naturalistic and rustic designs, provision of a range of pathway surface types and reducing the urbanisation of woodland, could increase the appeal of woodland to a wider demographic. Woodlands can fulfil a wide range of social functions. Where this is desirable, the woodland (new or existing) should be appropriately designed to reflect these intended roles and functions. This will require a range of facilities sympathetically provided.  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号