全文获取类型
收费全文 | 655篇 |
免费 | 48篇 |
专业分类
林业 | 87篇 |
农学 | 32篇 |
基础科学 | 2篇 |
129篇 | |
综合类 | 41篇 |
农作物 | 11篇 |
水产渔业 | 51篇 |
畜牧兽医 | 285篇 |
园艺 | 12篇 |
植物保护 | 53篇 |
出版年
2023年 | 3篇 |
2022年 | 17篇 |
2021年 | 32篇 |
2020年 | 20篇 |
2019年 | 11篇 |
2018年 | 27篇 |
2017年 | 38篇 |
2016年 | 39篇 |
2015年 | 26篇 |
2014年 | 32篇 |
2013年 | 48篇 |
2012年 | 47篇 |
2011年 | 53篇 |
2010年 | 28篇 |
2009年 | 21篇 |
2008年 | 28篇 |
2007年 | 40篇 |
2006年 | 36篇 |
2005年 | 28篇 |
2004年 | 27篇 |
2003年 | 27篇 |
2002年 | 21篇 |
2001年 | 6篇 |
2000年 | 12篇 |
1999年 | 3篇 |
1998年 | 6篇 |
1997年 | 3篇 |
1996年 | 2篇 |
1993年 | 3篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1971年 | 1篇 |
1969年 | 2篇 |
1968年 | 3篇 |
1967年 | 1篇 |
1913年 | 1篇 |
1906年 | 1篇 |
排序方式: 共有703条查询结果,搜索用时 15 毫秒
691.
Belhadj A Telef N Cluzet S Bouscaut J Corio-Costet MF Mérillon JM 《Journal of agricultural and food chemistry》2008,56(14):5781-5787
The grapevine (Vitis vinifera) is susceptible to many pathogens such as Botrytis cinerea, Plasmopara viticola, Erysiphe necator, and Eutypa lata. Phytochemicals are used extensively in vineyards to reduce pathogen infections, but the appearance of pesticide-resistant pathogen strains and the need for environmental protection require the use of alternative strategies. The phytohormone ethylene is assumed to play a role in the development of disease resistance. In the present study, we have treated grapevine foliar cuttings (Cabernet Sauvignon) with ethylene-releasing ethephon. This resulted in an increase in the number of pathogenesis-related protein (CHIT4c, PIN, PGIP, and GLU) gene copies and in an enhancement of phytoalexin biosynthesis by inducing the PAL and STS genes that correlated with the accumulation of stilbenes (antimicrobial compounds). Moreover, ethephon treatment triggered the protection of grapevine detached leaves and grapevine foliar cuttings against Erysiphe necator, the causal agent of powdery mildew (64% and 70%, respectively). These studies emphasize the major role of ethylene in grapevine defense. 相似文献
692.
693.
Sérgio T. Bosso Jacinta Enzweiler Rômulo S. Angélica 《Water, air, and soil pollution》2008,195(1-4):257-273
The immobilization of lead by the reaction with phosphate bearing materials is a promising remediation method for contaminated soils. Low soluble neo-formed lead-phosphate phases similar to chloropyromorphite [Pb5(PO4)3Cl], can control availability and mobility of lead in the environment, and consequently reduce human exposure, if soils are the main contamination pathway. We used three phosphate source materials [NaH2(PO4)3, commercial superphosphate and phosphate rock] to study lead immobilization in soil and mining waste samples. Products were examined after 1, 3 and 6 months of contact. The samples are from a contaminated area by former Pb mining and smelting activities, in southeastern Brazil, where epidemiological studies showed high lead blood levels in local population. The PBET (physiological based extraction test) bioaccessibility test was used to measure changes in the amount of soluble lead after sample treatment. Results show that the most efficient phosphate source was NaH2(PO4)3, which reduced lead solubility to 92% in acidic gastric conditions after the first month of contact. Superphosphate and phosphate rock also diminished Pb solubility, but the effect was more time dependent. None specific Pb–phosphate phases could be identified by XRD in whole treated samples, but the Pb–Ca–P elemental associations, observed on SEM images and EDS spectra of portions of the samples, combined with the reduced solubility, indicate that more insoluble lead phases were formed after the treatment. Based in these results, the in site phosphate application on soils to induce lead immobilization should be considered as a possible alternative to reduce human exposure at the area. 相似文献
694.
Gancel AL Grimplet J Sauvage FX Ollitrault P Brillouet JM 《Journal of agricultural and food chemistry》2006,54(17):6212-6218
Fusion of citrus diploid parental protoplasts generates allotetraploid hybrids which do not retain their parental traits with regard to leaf aroma compound biosynthesis. The aim of this study was thus to examine hybrid leaf proteomes in comparison with their parents. Leaf soluble proteins from two citrus allotetraploid hybrids (mandarin + lime and mandarin + kumquat) and their diploid parents (mandarin, lime, and kumquat) were submitted to 2-D gel electrophoresis. Leaf proteome maps of the tetraploid hybrids were compared with those of their parents on the basis of the presence/absence of spots and of their spot relative volumes. The two allotetraploid hybrid maps were found closer to that of their mandarin parent than to those of their nonmandarin parents in terms of the presence/absence of spots as well as at a quantitative level. This approach has to be related to the already observed dominance of mandarin in allotetraploids with regard to volatile compound biosynthesis in leaves. 相似文献
695.
Inhaled fluticasone reduces bronchial responsiveness and airway inflammation in cats with mild chronic bronchitis 总被引:4,自引:0,他引:4
Kirschvink N Leemans J Delvaux F Snaps F Jaspart S Evrard B Delattre L Cambier C Clercx C Gustin P 《Journal of Feline Medicine and Surgery》2006,8(1):45-54
This study investigated the effect of inhaled fluticasone on lower airway inflammation and bronchial responsiveness (BR) to inhaled carbachol in cats with very mild, chronic bronchitis (n = 5) that were compared with healthy cats serving as controls (n = 6). Chest radiographs, BR tests performed non-invasively by barometric whole body plethysmography (BWBP) and bronchoalveolar lavage (BAL) were performed before and after treatment. BR was quantified by calculating the concentration of carbachol inducing bronchoconstriction (C-Penh300%), defined as a 300% increase of baseline Penh, an index of bronchoconstriction obtained by BWBP. BAL fluid was analyzed cytologically and the oxidant marker 8-iso-PGF2alpha was determined. At test 1, healthy cats and cats with bronchitis were untreated, whereas for test 2 inhalant fluticasone (250 microg once daily) was administrated for 2 consecutive weeks to cats with bronchitis. Control cats remained untreated. Inhaled fluticasone induced a significant increase in C-Penh300% and a significant decrease of BAL fluid total cells, macrophages, neutrophils and 8-iso-PGF2alpha in cats with bronchitis, whilst untreated control cats did not show significant changes over time. This study shows that a 2-week fluticasone treatment significantly reduced lower airway inflammation in very mild bronchitis. BR could be successfully monitored in cats using BWPB and decreased significantly in response to inhaled fluticasone. 8-Iso-PGF2alpha in BAL fluid was responsive to treatment and appeared as a sensitive biomarker of lower airway inflammation in cats. 相似文献
696.
Júlia de Souza Lira Santos Eliane Teixeira Mársico Môsar Lemos Miguel Antônio Cinquini Flávio Alves da Silva Yasmin Bugini Dutra 《Journal Of Aquatic Food Product Technology》2018,27(1):48-60
The effect of Ultraviolet radiation type C (UV-C) radiation (0.100 ± 0.010 J/cm2) on shelf life of Arapaima gigas fillets stored at 4 ± 1°C for 18 days was investigated. The samples were analyzed for total aerobic mesophilic bacteria (TAMB) counts; total aerobic psychrotrophic bacteria (TAPB) counts; Enterobacteriaceae; purge loss; pH; lipid oxidation; total volatile bases (TVB-N); ammonia; biogenic amines (BAs); and L*, a*, and b* values. UV-C radiation increased (P < 0.05) the generation time of all bacterial groups evaluated, increasing the shelf life by 2 days. UV-C-treated fillets showed lower (P < 0.05) L* values, purge loss, pH, TVB-N, ammonia, and BAs levels than their control counterparts throughout the storage period. Moreover, UV-C treatment did not result (P > 0.05) in detrimental effects on lipid oxidation or a* and b* values. UV-C at 0.100 J/cm2 demonstrated a good potential for use in A. gigas fillets and, therefore, it could be applied at industrial scale. 相似文献
697.
Identifying obstacles and ranking common biological control research priorities for Europe to manage most economically important pests in arable,vegetable and perennial crops
下载免费PDF全文
![点击此处可从《Pest management science》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Jay Ram Lamichhane Monika Bischoff‐Schaefer Sylvia Bluemel Silke Dachbrodt‐Saaydeh Laure Dreux Jean‐Pierre Jansen Jozsef Kiss Jürgen Köhl Per Kudsk Thibaut Malausa Antoine Messéan Philippe C Nicot Pierre Ricci Jérôme Thibierge François Villeneuve 《Pest management science》2017,73(1):14-21
EU agriculture is currently in transition from conventional crop protection to integrated pest management (IPM). Because biocontrol is a key component of IPM, many European countries recently have intensified their national efforts on biocontrol research and innovation (R&I), although such initiatives are often fragmented. The operational outputs of national efforts would benefit from closer collaboration among stakeholders via transnationally coordinated approaches, as most economically important pests are similar across Europe. This paper proposes a common European framework on biocontrol R&I. It identifies generic R&I bottlenecks and needs as well as priorities for three crop types (arable, vegetable and perennial crops). The existing gap between the market offers of biocontrol solutions and the demand of growers, the lengthy and expensive registration process for biocontrol solutions and their varying effectiveness due to variable climatic conditions and site‐specific factors across Europe are key obstacles hindering the development and adoption of biocontrol solutions in Europe. Considering arable, vegetable and perennial crops, a dozen common target pests are identified for each type of crop and ranked by order of importance at European level. Such a ranked list indicates numerous topics on which future joint transnational efforts would be justified. © 2016 Society of Chemical Industry 相似文献
698.
699.
Marcela Carvalho Andrade Alex Antônio da Silva Regis de Castro Carvalho Juliana de Andrade Santiago Alisson Marcel Souza de Oliveira David Merrill Francis Wilson Roberto Maluf 《Genetic Resources and Crop Evolution》2018,65(6):1671-1685
Pest resistance in Solanum galapagense has been associated with the presence of type IV glandular trichomes and allelochemicals. Knowledge of the genetic factors involved in determining the presence and type of trichomes may assist in the process of gene introgression for development of pest resistant tomato cultivars. In this study, we sought to identify QTLs associated with the presence of type IV trichomes in an F2 population derived from the interspecific cross of Solanum lycopersicum TOM-684?×?S. galapagense accession LA1401. Two QTLs contributing to type IV trichome occurrence and density were detected, one major QTL (gal.IV-2), responsible for 35.22% of phenotypic variation, was located on chromosome 2. The other QTL (gal.IV-3) was located on chromosome 3, and explained 23.35% of the phenotypic variation in the F2 population. These QTLs were responsible for 26.44 and 3.37% of the variation observed in a progeny derived from a backcross to TOM-684. The same QTLs were also associated with type II?+?III non-glandular trichomes, whose densities were negatively correlated to those of type IV trichomes, suggesting that the loci found may have pleiotropic effects for high type IV/low type II?+?III trichome densities. Our results indicate that the inheritance for type IV trichomes can be explained by a few genetic factors affecting the presence of a gland and the density of trichomes. These results further suggest a revision to trichome classification used for tomato may be appropriate. 相似文献
700.
Natália R. Barboza Mônica M. Cordeiro Pricila A. Santos Pollyana S. Queiroz Versiane A. Leão Renata Guerra-Sá 《Water, air, and soil pollution》2018,229(1):19
Bioremediation is a method of removing manganese from wastewaters, and many bacterial species with a role in manganese bioremediation have been identified over several decades. Using K medium with Mn(II), a bacterial consortium was obtained from water sample collected from a mine drainage in southeastern Brazil (Minas Gerais, Brazil), and the isolates were identified as Klebsiella oxytoca using both biochemical and 16S rRNA phylogenetic analysis. Among such isolates, sample SA8 was tested for its manganese removal capability during a week-long experiment in K medium amended with manganese sulfate. Growth of isolate SA8 produced an increase in pH concomitantly to Mn(II) removal, which was not observed in the abiotic control. Manganese removal occurred through oxidation as confirmed by reaction with leucoberbelin blue, and therefore, a new potential application for K. oxytoca in mine water bioremediation is proposed. 相似文献