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   211篇
  免费   22篇
林业   17篇
农学   6篇
  49篇
综合类   5篇
农作物   21篇
水产渔业   7篇
畜牧兽医   83篇
园艺   5篇
植物保护   40篇
  2023年   2篇
  2022年   4篇
  2021年   8篇
  2020年   11篇
  2019年   13篇
  2018年   11篇
  2017年   9篇
  2016年   11篇
  2015年   17篇
  2014年   6篇
  2013年   8篇
  2012年   17篇
  2011年   14篇
  2010年   15篇
  2009年   7篇
  2008年   18篇
  2007年   13篇
  2006年   12篇
  2005年   10篇
  2004年   6篇
  2003年   6篇
  2002年   5篇
  2001年   1篇
  2000年   2篇
  1996年   1篇
  1992年   1篇
  1983年   2篇
  1980年   1篇
  1978年   1篇
  1977年   1篇
排序方式: 共有233条查询结果,搜索用时 0 毫秒
1.
To control downy mildew of sweet basil (Ocimum basilicum L.), incited by Peronospora belbahrii Thines, a number of compounds were tested in 2011 and 2012 under glasshouse conditions. These included copper-based fungicides, biocontrol agents, and compounds previously reported to induce resistance in plants to pathogens. Results were compared with those provided by fungicides registered for downy mildew control in Italy. The tested compounds were used alone or applied in rotation in spray programs. In all trials, the greatest reduction in disease incidence and severity was found with treatments that included metalaxyl-M?+?copper hydroxide, a mineral fertilizer ‘Alexin’, mandipropanid, and azoxystrobin. The glucohumates activator complex and acibenzolar-S-methyl also provided significant disease control (P?<?0.05). The mineral fertilizer Alexin, the glucohumates activator complex and acibenzolar-S significantly reduced disease incidence and severity 20 days after the last treatment compared with the untreated control (P?<?0.05). Among the copper-based products, the greatest reductions in disease incidence and severity were provided by copper hydroxide with terpenic alcohols and copper oxychloride?+?copper hydroxide. The mineral fertilizer Kendal and prohexadione-Ca, as well as mustard oil, partially reduced disease incidence and severity compared with the untreated control (P?<?0.05), whereas the biocontrol agent Bacillus subtilis QST 713 and thyme oil extract were not effective in two out of three trials. When different combinations of various products used in rotation were tested, effective control was found either using a rotation of fungicides with compounds that can induce resistance, as well as by using rotation with different resistance-inducing compounds on their own.  相似文献   
2.
尖镰孢菌枯萎病是意大利西北部芝麻菜栽培品种(Eruca vesicaria)和野生品种(Diplotaxis spp.)上的重要病害之一,常引起严重的损失。为评价芝麻菜品种对尖镰孢菌枯萎病的抗性,2004年6~11月,选用了44个栽培及野生品种资源在玻璃温室进行抗性试验,使用浓度为1×10~6cfu/ mL的孢子悬浮液蘸根法人工接种30天苗龄的芝麻菜幼苗,以分离自芝麻菜两个不同野生品种的菌株Fus.Ruc.9A/02和Fus.Ruc.13/03,以及分离自栽培和野生品种的32个菌株混合(MIX),分别作为抗病试验接种体,每次接种试验设A、B、C三个重复。整个试验重复进行2次。调查病害引起的死苗率(%)和病情指数(DI),作为评价芝麻菜品种抗性差异的两项指标。研究结果显示,这两项指标间的相关性极显著(P<0.01),即表明可采用其中一项指标评价芝麻菜品种对尖镰孢菌枯萎病的抗性。供试的44个栽培及野生芝麻菜品种中,多数品种抗尖镰孢茵茵株Fus.Ruc.13/ 03,而对菌株Fus.Ruc.9A/02及菌株混合MIX表现为易感性,而且这些易感品种在菌株Fus.Ruc.9A/02及菌株混合MIX两试验中的抗性表现较为一致,Fus.Ruc.9A/02和MIX的毒性也更强于Fus.Ruc.13/03菌株。芝麻菜品种12/03和品种20/03高抗菌株混合MIX,品种6/03和品种7/04高抗菌株Fus.Ruc.9A/02,而品种9/02、2/03、5/03、6/03、7/03、9/03、11/03、12/03、20/03、21/03、24/03、3/04、6/04、7/04和11/04高抗菌株Fus.Ruc.13/03。  相似文献   
3.
A number of N2-alkyl and N2-acyl derivatives of guanosine 5'-phosphate (GMP) have been synthesized and tested for their synergistic effect with monosodium L-glutamate (MSG), the prototypical substance imparting umami taste to savory-based foods. Capacities to enhance the taste intensity of MSG (gamma values) were estimated through subjective comparisons of MSG/nucleotide mixtures in water with appropriate solutions of MSG alone. Assuming beta = gamma[nucleotide]/gamma[IMP], beta values of the N2-substituted GMPs were found in the range 1.2-5.7. Such values appear to be related to the chain length of the substituent in the 2-position of the purine nucleus and dependent on the replacement of a CH 2 group with an S atom and/or with an alpha-CO group. These findings indicate that the exocyclic NHR group of the guanine moiety is actively implicated in the synergism between GMP derivatives and MSG. Theoretical calculations suggest that an anti conformation is probably assumed by ribonucleotide molecules interacting with umami receptors.  相似文献   
4.
5.
6.
7.
Tropical Animal Health and Production - A cross-sectional study was conducted to determine the seroprevalence and the risk factors associated with C. burnetii infection in cattle in the state of...  相似文献   
8.
BACKGROUND: Pituitary apoplexy in humans is a clinical syndrome resulting from sudden infarction, hemorrhage, or both in a normal or an adenomatous pituitary gland. OBJECTIVE: Describe a clinical syndrome in dogs similar to pituitary apoplexy in humans. ANIMALS: Four dogs exhibiting a sudden onset of neurologic signs. METHODS: A retrospective study was used, including clinical examination, computed tomography (CT), postmortem examination, and histopathology of the brain. Pituitary tissue from 3 of the dogs was subjected to immunocytochemistry. RESULTS: Four dogs (2 Mongrels, 1 Bordeaux Dog, and 1 Cocker Spaniel; median age, 11 years; median body weight, 20.5 kg) presented with acute neurologic signs including depression (n = 3), behavioral changes (n = 1), vision loss (n = 1), seizures (n = 1), and collapse (n = 1). CT disclosed suprasellar infarction, hemorrhage, or both associated with a pituitary macroadenoma in 3 dogs and a frank hemorrhage in a nonadenomatous pituitary gland in 1 dog. CT findings were correlated with postmortem findings, and pituitary apoplexy was confirmed by histopathology and immunocytochemistry of the pituitary tissue. CONCLUSIONS AND CLINICAL IMPORTANCE: This study provides histopathologic evidence of pituitary apoplexy in dogs. The results are relevant for future diagnosis and treatment of pituitary disease in dogs.  相似文献   
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