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   675篇
  免费   16篇
  国内免费   2篇
林业   28篇
农学   22篇
基础科学   4篇
  74篇
综合类   125篇
农作物   13篇
水产渔业   11篇
畜牧兽医   348篇
园艺   13篇
植物保护   55篇
  2023年   5篇
  2020年   8篇
  2019年   4篇
  2018年   7篇
  2017年   7篇
  2016年   7篇
  2014年   7篇
  2013年   23篇
  2012年   41篇
  2011年   64篇
  2010年   21篇
  2009年   19篇
  2008年   31篇
  2007年   33篇
  2006年   25篇
  2005年   26篇
  2004年   21篇
  2003年   14篇
  2002年   15篇
  2001年   23篇
  2000年   15篇
  1999年   17篇
  1998年   8篇
  1997年   6篇
  1996年   7篇
  1995年   14篇
  1994年   8篇
  1992年   10篇
  1991年   15篇
  1990年   14篇
  1989年   10篇
  1988年   13篇
  1987年   8篇
  1986年   14篇
  1985年   6篇
  1984年   12篇
  1983年   11篇
  1982年   7篇
  1981年   8篇
  1980年   7篇
  1979年   4篇
  1978年   4篇
  1976年   5篇
  1975年   5篇
  1974年   4篇
  1973年   4篇
  1972年   6篇
  1971年   5篇
  1970年   11篇
  1967年   4篇
排序方式: 共有693条查询结果,搜索用时 15 毫秒
611.
The purpose of this study was to provide an initial assessment of the potential biologic activity of toceranib phosphate (Palladia?, Pfizer Animal Health, Madison, NJ, USA) in select solid tumours in dogs. Cases in which toceranib was used to treat dogs with apocrine gland anal sac adenocarcinoma (AGASACA), metastatic osteosarcoma (OSA), thyroid carcinoma, head and neck carcinoma and nasal carcinoma were included. Clinical benefit (CB) was observed in 63/85 (74%) dogs including 28/32 AGASACA [8 partial response (PR), 20 stable disease (SD)], 11/23 OSAs (1 PR and 10 SD), 12/15 thyroid carcinomas (4 PR and 8 SD), 7/8 head and neck carcinomas [1 complete response (CR), 5 PR and 1 SD] and 5/7 (1 CR and 4 SD) nasal carcinomas. For dogs experiencing CB, the median dose of toceranib was 2.8 mg kg(-1) , 36/63 (58.7%) were dosed on a Monday/Wednesday/Friday basis and 47/63 (74.6%) were treated 4 months or longer. Although these data provide preliminary evidence that toceranib exhibits CB in dogs with certain solid tumours, future prospective studies are necessary to define its true activity.  相似文献   
612.
613.
614.
615.
616.
617.
618.
Inconsistent results of ethephon in field experiments in olive (Olea europaea L.) are attributed to climatic differences and irrigation regimes.Physical measurements, using 14C-2-chloroethyl phosphonic acid (14C-CEPA) at pH 6.3 indicated 60% degradation within 5 h at 40° C. Rate of degradation at 20, 30, 40 and 50° C at relative humidities of 37 or 70% was higher than at similar temperatures at 3 or 93% relative humidities. Temperature-dependent degradation of ethephon was similar on the surface of detached leaves, intact plants or in the glass test tube.Non-irrigated trees responded better than irrigated trees to ethephon treatment. Uptake and translocation of 14C-CEPA as a function of the water content was measured in a model system of detached branches. Uptake of 14C-CEPA was increased and translocation decreased in partially desiccated branches. The increased uptake and decreased translocation in desiccated branches is in accordance with the response of non-irrigated trees in the field.  相似文献   
619.
In connection with the measuring of parameters of the protein metabolism in parallel experiments, the energy metabolism of 6 chickens (origin Tetra B) in the live weight range between approximately 100 and 1,800 g was determined under conditions of restricted energy supply. 3 animals each received a feed mixture containing 20% (animal group 1) and 38% (animal group 2) crude protein. The amount of feed was daily increased by 1.5 g DM. The digestibility of energy and nitrogen was independent of the age. 66.3 +/- 3.3% and 64.0 +/- 5.0% resp. of the metabolisable energy were utilised for protein and fat retention. The energy maintenance requirement, determined at a live weight of 2,000 g, was independent of protein supply and averaged in the two animal groups 434 +/- 40 kJ metabolisable energy/kg live weight 0.75 . d. The result of multiple regression was, for the growth period investigated, an energy maintenance requirement of 403 +/- 32 kJ metabolisable energy/kg live weight 0.75 . d. 1.77 and 1.38 J metabolisable energy resp. were required for 1 J protein or fat retention. The energy requirement for protein retention was independent of the degree of protein supply. The results from the measuring of energy metabolism are discussed in connection with the kinetic parameters of protein metabolism ascertained in parallel experiments.  相似文献   
620.
Psychomotor seizures (temporal lobe epilepsy) were diagnosed in a dog based on history, clinical findings and electroencephalography. Long-term seizure control was achieved with carbamazepine, despite serum drug concentrations which were low to unmeasurable. It is suggested that serum levels of carbamazepine are not a useful guide to clinical efficacy in the dog, that an unmeasured metabolite of carbamazepine may account for the anti-convulsant activity and that carbamazepine may be potentially useful in treating certain canine seizure disorders.  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