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   112篇
  免费   7篇
林业   7篇
农学   6篇
  18篇
综合类   8篇
农作物   5篇
水产渔业   7篇
畜牧兽医   51篇
园艺   3篇
植物保护   14篇
  2022年   9篇
  2021年   1篇
  2020年   2篇
  2019年   4篇
  2018年   4篇
  2017年   5篇
  2016年   3篇
  2015年   2篇
  2014年   4篇
  2013年   21篇
  2012年   6篇
  2011年   10篇
  2010年   7篇
  2009年   3篇
  2008年   3篇
  2007年   1篇
  2006年   4篇
  2005年   6篇
  2004年   2篇
  2003年   7篇
  2002年   4篇
  2001年   2篇
  2000年   2篇
  1999年   3篇
  1991年   1篇
  1988年   1篇
  1985年   1篇
  1977年   1篇
排序方式: 共有119条查询结果,搜索用时 15 毫秒
1.
DAS-ELISA proved to be reliable enough to detect a latent infection by Tomato spotted wilt virus (TSWV) in asymptomatic stock plants of chrysanthemum. A high density of Frankliniella occidentalis, the predominant vector, in the presence of latently infected stock plants resulted in a high incidence of disease in the chrysanthemum production field. The incidence of disease was low when the vector thrips were not abundant in spite of the presence of latently infected stock plants. These results suggest that an infestation of the vector thrips causes severe secondary spread of TSWV originating from latently infected stock plants in chrysanthemum production fields. Received 27 July 2001/ Accepted in revised form 27 November 2001  相似文献   
2.
Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) is widely used as a flame retardant and is known to exhibit anti-androgenic effects in vitro and in vivo. To assess the reproductive toxicity potency of TDCIPP, we investigated the effects of 7 days of TDCIPP oral administration on epididymal sperm motion and concentration in adult male Wistar–Imamichi rats. Thirty-five days after the final administration, sperm parameters were evaluated by computer-assisted sperm analysis. Results showed that sperm swimming progression and vigor and sperm concentration in TDCIPP-treated rats were unexpectedly higher than those in control rats. TDCIPP did not significantly affect the percentage of motile sperms or sperm swimming pattern. These results contribute to the understanding of the biological effects of TDCIPP.  相似文献   
3.
<正>Dear Editor,Rice is an important staple food crop in Asia, but the anaerobic soil conditions in rice fields cause emission of the potent greenhouse gas, methane(CH4)(Le Mer and Roger,2001), and promote the accumulation of arsenic(As) in the grain(Le Mer and Roger, 2001; Khanam et al., 2020).To facilitate sustainable agriculture, using wastewater as an organic fertilizer is essential for reducing wastewater treatment-associated energy consumption and the recycling of wastewate...  相似文献   
4.
Journal of Plant Diseases and Protection - Three isolates of chrysanthemum white rust fungus, Puccinia horiana, were collected from two regions in Hiroshima Prefecture, Japan, in 2017. In an in...  相似文献   
5.
6.
Forty-six isolates of Taylorella equigenitalis were analysed by pulsed-field gel electrophoresis (PFGE) after separate digestion of the genomic DNA with ApaI and with NotI. The isolates had been obtained from horses in six European countries and were classified into 18 genotypes. In Belgium, 2 genotypes were detected in 2 isolates, in England 9 among 15, in Finland 2 in 2, in France 2 among 10, in Sweden 3 among 5, and in Switzerland 3 among 12. Two English isolates and 4 French isolates gave identical PFGE profiles to those of Kentucky 188 from the United States. A common genotype was found in 5 isolates from Belgium and England and also in 10 isolates from France and Switzerland. The analysis of genomic DNA from 12 isolates of T. equigenitalis obtained from male horses in France, Sweden and Switzerland gave no evidence of a sex-related difference in the genomic DNA. Genomic DNA from 11 streptomycin (STM)-susceptible isolates obtained in Sweden and Switzerland were classified into four genotypes by PFGE. Each of the six genotypes determined among the 17 isolates from these two countries had single phenotypes for resistance or susceptibility to STM.  相似文献   
7.
Three isolates of Chrysanthemum stem necrosis virus (CSNV) were obtained from chrysanthemum plants in distinct regions of Japan in 2006 and 2007. All the original host plants showed severe necrotic symptoms on the leaves and stems. Amino acid sequence data of the nucleocapsid protein genes of the three isolates (CbCh07A, TcCh07A, and GnCh07S) showed high identities with those of two other CSNV isolates, HiCh06A L1 from Japan and Chry1 from Brazil. Furthermore, for the first time the complete nucleotide sequence of the S RNA was determined for CSNV (isolate HiCh06A). In phylogenetic analysis based on the non-structural protein genes from the genus Tospovirus, HiCh06A L1 was placed in the same genetic group as Tomato spotted wilt virus (TSWV) and Impatiens necrotic spot virus. Host range examination for isolates HiCh06A L1 and CbCh07A showed that green pepper (cv. ‘Kyoyutaka’, ‘Saitamawase’, ‘Tosakatsura’, ‘L3 sarara’ and ‘L3 miogi’) and tomato (cv. ‘Sekaiichitomato’) were systemically susceptible hosts, whereas TSWV-resistant Solanaceae species, Capsicum chinense, Lycopersicon peruvianum and a TSWV-resistant cultivar of green pepper (cv. TSR miogi), were resistant.  相似文献   
8.
The relationship between cellular breakdown and the activities of some cell-wall degrading enzymes (endocellulase, exocellulase, polygalacturonase, pectin methylesterase and β-galactosidase) was investigated in the watercored tissue of Japanese pear fruit, Pyrus serotina Rehder var. ‘Culta’ Rehder, cultivar ‘93-3’. In watercored tissue at an early stage, endocellulase activity, especially neutral form, was higher than that in healthy tissue. As the symptom of the watercore developed, polygalacturonase and β-galactosidase activities in the watercored tissue increased compared with those in healthy tissue. This indicated that in tissues at an early stage of watercore, these cell-wall degrading enzymes were activated, and operative in the breakdown of the cell wall. However, exocellulase and pectin methylesterase were not activated in the watercored tissue. The breakdown of cellular tissue was also supported by the fact that the DNA and protein contents decreased in the watercored tissue. Invertase activity decreased in the watercored tissue, compared with healthy tissue, and it was suggested that its decrease could be one of the causes of sucrose accumulation in the watercored tissue.  相似文献   
9.
A 4-year-old Beagle dog was presented for investigation of a left pelvic limb gait abnormality. Neurolocalisation indicated a lumbar (L2 to L5) spinal cord lesion. On magnetic resonance imaging (MRI), an intramedullary mass was demonstrated at L3. The mass was partially removed under general anaesthesia and a diagnosis of ependymoma was made on histological examination. The dog was treated with postoperative orthovoltage x-ray radiation (total dose; 44 Gy given in 11 fractions over a 4 week period) combined with low dose carboplatin (25 mg/m2). The dog was alive 16 months after surgery without further neurological deficits. No further tumour growth was detected on subsequent MRI evaluations.  相似文献   
10.
Objective-To evaluate effects of extracellular lactate on viability, shape change, lactate metabolism, and reactive oxygen species (ROS) production in equine polymorphonuclear leukocytes (PMNs). Sample-PMNs isolated from equine venous blood samples. Procedures-PMNs were incubated with 0 to 300mM lactate for 30 minutes before each experiment. Viability was assessed via trypan blue exclusion. Shape change was assessed via flow cytometry and light microscopy. Relative quantification of monocarboxylic acid transporter and lactate dehydrogenase lactate dehydrogenase (LDH) isotype mRNAs was performed with a real-time PCR assay. Effects of lactate at a pH of 7.4 to 6.0 on ROS production in response to phorbol 12-myristate 13-acetate, opsonized zymosan, or N-formyl-methionyl-leucyl-phenylalanine was assessed by luminol-dependent chemiluminescence. Results-Lactate had no effect on viability of PMNs but did alter their size and density. Monocarboxylic acid transporter 1 and lactate dehydrogenase B mRNA values were not altered. Monocarboxylic acid transporter 4 and lactate dehydrogenase A mRNA values were significantly decreased. Lactate incubation of cells significantly decreased PMN-derived luminol-dependent chemiluminescence and induced different sensitivities to stimulants (phorbol 12-myristate 13-acetate, opsonized zymosan, and N-formyl-methionyl-leucyl-phenylalanine). The response ratio to N-formyl-methionyl-leucyl-phenylalanine revealed that PMNs were primed by incubation with up to 50mM lactate, significantly increasing the production of ROS. Incubation with lactate and acidic pH caused a synergistic effect on ROS production. Conclusions and Clinical Relevance-Extracellular lactate potentially has a direct effect on the capacity to produce ROS by equine PMNs, which may be associated with alterations in innate immune functions within a short period after high-intensity exercise.  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