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   338篇
  免费   4篇
综合类   12篇
水产渔业   1篇
畜牧兽医   327篇
植物保护   2篇
  2020年   2篇
  2018年   2篇
  2017年   2篇
  2014年   3篇
  2013年   64篇
  2010年   3篇
  2009年   1篇
  2008年   1篇
  2006年   2篇
  2003年   3篇
  2002年   1篇
  1999年   1篇
  1998年   6篇
  1997年   2篇
  1996年   3篇
  1995年   1篇
  1994年   1篇
  1993年   3篇
  1992年   1篇
  1991年   3篇
  1990年   1篇
  1983年   1篇
  1976年   8篇
  1975年   2篇
  1974年   1篇
  1972年   1篇
  1971年   1篇
  1970年   2篇
  1969年   2篇
  1968年   15篇
  1967年   2篇
  1966年   6篇
  1965年   2篇
  1964年   7篇
  1963年   7篇
  1962年   3篇
  1961年   2篇
  1960年   26篇
  1959年   10篇
  1957年   21篇
  1956年   12篇
  1955年   26篇
  1954年   23篇
  1944年   10篇
  1943年   5篇
  1942年   6篇
  1941年   19篇
  1940年   6篇
  1927年   5篇
  1925年   1篇
排序方式: 共有342条查询结果,搜索用时 687 毫秒
121.
Abstract

Extract

Sir,—We should like to take this opportunity to congratulate Messrs Cordes, Dodd and O'Hara (1964 Cordes, D. O., Dodd, D. C. and O'Hara, P. J. 1964. N.Z. vet J., 12: 9595. [Taylor &; Francis Online] [Google Scholar]) on their excellent article on bovine mycotic abortion and pneumonia in New Zealand, and at the same time mention certain complementary features of these conditions as noted in Tasmania.  相似文献   
122.
123.
Extract

Sir, — Diagnostic parasitologists are often required to examine autolysed gastro-intestinal tracts. Such specimens are aesthetically unpleasant and fragmentation of worms may have occurred, making it impossible either to identify or count them. Autolysis often occurs following collection while the specimen is in transit to the laboratory.  相似文献   
124.
Extract

Sir, — Four suckling piglets have been examined at this laboratory from a Taranaki herd in which sudden death, chorea and convulsions were the clinical features.  相似文献   
125.
Extract

Sir, — Recently I read with interest a letter by Fowler in the January–February 1976 issue of the Journal.  相似文献   
126.
Abstract

Extract

Sir, — We wish to record the presence of the tick Rhipicephalus sanguineus on a dog imported from Australia. This tick is mainly parasitic on dogs although on rare occasions it has been collected from non-canine hosts (Roberts, 1965 Roberts, F. H. S. 1965. The taxonomie status of the species of the genera Rhipicephalus (Koch) and Boophilus (Curtice) occurring in Australia. Aust. J. Zool., 13: 491523.  [Google Scholar]). Experimentally it has been shown capable of transmitting a wide variety of serious diseases but its role as a natural vector of many of them is unknown. In Australia it has been demostrated as being naturally infected with Coxiella burnetii (Smith, 1942 Smith, D. J. W. 1942. Studies on the epidemiology of Q Fever. Aust. J. exp. Biol. med. Sci., 20: 295296.  [Google Scholar]) and is recorded from all continents and some oceanic islands lying between latitudes 50°N and 36°S (Roberts, 1970 Roberts, F. H. S. 1970. Australian ticks, 8787. CSIRO.  [Google Scholar]). Auckland falls within this boundaries and therefore it is not unreasonable to suggest that R. sanguineus could become established in New Zealand.  相似文献   
127.
Extract

Sir,—I should like to make a request to interested veterinarians for live specimens of the rare condition in sheep — testicular feminization.  相似文献   
128.
129.
Sensitivity of boreal forest carbon balance to soil thaw   总被引:6,自引:0,他引:6  
We used eddy covariance; gas-exchange chambers; radiocarbon analysis; wood, moss, and soil inventories; and laboratory incubations to measure the carbon balance of a 120-year-old black spruce forest in Manitoba, Canada. The site lost 0.3 +/- 0.5 metric ton of carbon per hectare per year (ton C ha-1 year-1) from 1994 to 1997, with a gain of 0.6 +/- 0.2 ton C ha-1 year-1 in moss and wood offset by a loss of 0.8 +/- 0.5 ton C ha-1 year-1 from the soil. The soil remained frozen most of the year, and the decomposition of organic matter in the soil increased 10-fold upon thawing. The stability of the soil carbon pool ( approximately 150 tons C ha-1) appears sensitive to the depth and duration of thaw, and climatic changes that promote thaw are likely to cause a net efflux of carbon dioxide from the site.  相似文献   
130.
Shear-wave splitting across the fast-spreading East Pacific Rise has been measured from records of SKS and SKKS phases on the ocean-bottom seismometers of the Mantle Electromagnetic and Tomography (MELT) Experiment. The direction of fast shear-wave polarization is aligned parallel to the spreading direction. Delay times between fast and slow shear waves are asymmetric across the rise, and off-axis values on the Pacific Plate are twice those on the Nazca Plate. Splitting on the Pacific Plate may reflect anisotropy associated with spreading-induced flow above a depth of about 100 km, as well as a deeper contribution from warm asthenospheric return flow from the Pacific Superswell region.  相似文献   
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