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   38篇
  免费   0篇
农学   1篇
综合类   9篇
水产渔业   2篇
畜牧兽医   23篇
植物保护   3篇
  2013年   1篇
  2012年   1篇
  2010年   2篇
  2006年   1篇
  1998年   1篇
  1997年   1篇
  1995年   2篇
  1994年   2篇
  1993年   2篇
  1992年   1篇
  1990年   2篇
  1988年   1篇
  1986年   2篇
  1980年   1篇
  1963年   4篇
  1958年   5篇
  1957年   2篇
  1956年   4篇
  1955年   1篇
  1954年   2篇
排序方式: 共有38条查询结果,搜索用时 296 毫秒
1.
Interactions between Erysiphe graminis f.sp. tritici and Septoria nodorum on wheat were studied in the greenhouse and in a 2-year field experiment using artificial inoculation. The integrated form of the logistic growth model dy/dt = ry (1 -y/K ), with infection rate r and final accumulated disease K , was fitted to the disease progress data. Septoria nodorum substantially reduced the disease severities of E. graminis , and caused significant reductions of at least 60% in final accumulated disease K of E. graminis. In the field trials, E. graminis increased the final accumulated disease K of S. nodorum. Owing to the extremely low severity of E. graminis , the increase of S. nodorum severity was small, and significance was given in one of the two years only, with an increase in K of roughly 30%. In the pot experiment, final accumulated disease K of S. nodorum remained unchanged, but there was a significant 30% increase in the infection rate r of S. nodorum. The difference between field and pot trials was explained by the climatic conditions in the greenhouse which excluded secondary infections of 5. nodorum , and which are important factors for disease progress in the field.  相似文献   
2.
The cortisone-induced de novo synthesis of liver glucose-6-phosphatase, fructose-1, 6-diphosphatase, aldolase, and lactic dehydrogenase was prevented by injections of Actinomycin D in the rat. In the in vitro assay systems, addition of actinomycin exerted no effect on the enzyme activities examined. The evidence favors the concept that the increased gluconeogenesis induced by corticoids entails at a certain stage an increased rate in the synthesis of gluconeogenic enzymes.  相似文献   
3.
A modified technique for fixation of the deferent ducts to the abdominal wall as a therapy for urinary incontinence caused by urethral sphincter mechanism incompetence (USMI) in male dogs is described, and the results in seven dogs are reported. The goal of this treatment was to achieve an effect similar to colposuspension in female dogs with USMI. An increase in urethral length of an average of 28 mm was obtained (range, 5 to 50 mm, measured radiographically). Preoperatively, the neck of the bladder was located intrapelvically in five of seven dogs. Postoperatively, the neck of the bladder was located intra-abdominally, near the caudo-ventral abdominal wall, in all dogs. After a follow-up period of 12 to 49 months, the response to surgery, based on lack of or decrease of incontinence, was excellent in three dogs, good in another three, and poor in one dog.  相似文献   
4.
Eight cases of pharyngeal mucoceles were diagnosed in 49 dogs with salivary mucoceles over a 7 year period. Five of the eight pharyngeal mucoceles were seen in Miniature Poodles. The presenting complaint in all eight dogs was labored breathing, with or without coughing upon excitement or exercise. Diagnosis was made by aspirating a thick mucoid fluid from the pharyngeal swelling. Treatment consisted of resection of the mandibular and sublingual salivary glands on the affected side and aspiration of the mucocele in all eight dogs, and resection of redundant pharyngeal tissue in five dogs. Time to follow-up ranged from 1.5 to 7.5 years. There were no postsurgical complications or recurrences of the mucocele.  相似文献   
5.
6.
Equilibrium was achieved in centrifugal fields with tobacco mosaic virus by the Beams magnetically suspended ultracentrifuge. An attempt was made to account for the earth's gravitational component by using tilted cells in the rotor. The determinations of particle weight on highly uniform rods of tobacco mosaic virus in the apparent absence of nonideal behavior gave a value of (41.6 +/- 0.1) 10(6).  相似文献   
7.
A weather-based simulation model of population development of Leptinotarsa decemlineata (Colorado beetle) has been extended to include the effects of insecticides. The dynamics of larvae (1st to 4th instar) and the resulting abundance of the adult summer generation has been simulated under the influence of insecticide applications. To describe the mortality caused by different insecticides on the stages of development of L. decemlineata, detailed experimental data are necessary. In this paper, preliminary experience to adapt the SIMLEP computer model to simulate insecticide action on L. decemlineata populations are published for the first time. These investigations aim at developing a more complete model which will be applicable to agricultural practice, not only to predict the dates of density maxima of the developmental stages of L. decemlineata, but also to estimate the need for and the required extent of insecticide applications, i.e. to guarantee optimum results from pesticide treatments.  相似文献   
8.
9.
10.
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