全文获取类型
收费全文 | 285篇 |
免费 | 22篇 |
专业分类
林业 | 19篇 |
农学 | 9篇 |
基础科学 | 8篇 |
69篇 | |
综合类 | 10篇 |
农作物 | 29篇 |
水产渔业 | 28篇 |
畜牧兽医 | 89篇 |
园艺 | 11篇 |
植物保护 | 35篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 7篇 |
2021年 | 8篇 |
2020年 | 14篇 |
2019年 | 15篇 |
2018年 | 18篇 |
2017年 | 12篇 |
2016年 | 9篇 |
2015年 | 9篇 |
2014年 | 10篇 |
2013年 | 22篇 |
2012年 | 17篇 |
2011年 | 20篇 |
2010年 | 12篇 |
2009年 | 10篇 |
2008年 | 18篇 |
2007年 | 11篇 |
2006年 | 16篇 |
2005年 | 10篇 |
2004年 | 7篇 |
2003年 | 11篇 |
2002年 | 11篇 |
2001年 | 5篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1977年 | 3篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1968年 | 1篇 |
1935年 | 1篇 |
排序方式: 共有307条查询结果,搜索用时 31 毫秒
11.
12.
Cohen Abigail L. Illan Javier Gutierrez Pfeiffer Vera W. Wohleb Carrie H. Crowder David W. 《Journal of pest science》2022,95(1):315-325
Journal of Pest Science - Long-term monitoring networks that generate data on pest abundance are the foundation of integrated pest management. Monitoring can estimate local risk from pests and... 相似文献
13.
The first records of the invasive pest Drosophila suzukii in the South American continent 总被引:1,自引:0,他引:1
Maríndia Deprá Jean Lucas Poppe Hermes José Schmitz Daniela Cristina De Toni Vera L. S. Valente 《Journal of pest science》2014,87(3):379-383
This paper presents the first report of the occurrence of Drosophila suzukii (Diptera: Drosophilidae) in South America. Several samples were collected during various seasons in 2012 and 2013, and a significant number of individuals were obtained and identified. Based on the data recorded during each sampling campaign, including the locality, temperature, time of year, and number of individuals collected, several conclusions were drawn about the development of this invasion in southern Brazil. 相似文献
14.
15.
Geuns JM Malheiros RD Moraes VM Decuypere EM Compernolle F Buyse JG 《Journal of agricultural and food chemistry》2003,51(4):1095-1101
In intubation experiments (643-1168 mg per animal), most of the stevioside administered to chickens was recovered unchanged in the excreta, and only about 2% was converted into steviol. Neither stevioside nor steviol could be found in the blood. In chronic studies (667 mg of stevioside/kg of feed) with laying hens and meat-type chickens, no significant differences were found in feed uptake, weight gain, and feed conversion as the result of stevioside administration. The egg production and egg composition of laying hens were not influenced. Most of the stevioside taken up was found untransformed in the excreta, and about 21.5% or 7.3% was converted to steviol by meat-type chickens or laying hens, respectively. No stevioside or steviol could be detected in the blood or in the eggs of the different groups of animals. In anaerobic incubation experiments with chicken excreta, only a 20% conversion of stevioside into steviol was found. No harmful effects were observed in the chronic stevioside supplementation experiments nor in the intubation experiments in which very high stevioside doses were given. 相似文献
16.
M. G. Vizcarra Mendoza C. Martínez Vera F. V. Caballero Domínguez 《Biosystems Engineering》2003,86(4):441-446
The physical characteristics, thermodynamic and transport properties of amaranth seeds relevant to the modelling and simulation of the drying processes of these seeds were studied. The water activity as a function of the temperature and moisture content was modelled by means of the Henderson's expression from water activity experimental data. The desorption–vaporisation heat was also calculated. From the solution to Fick's second law for a spherical geometry and assuming equilibrium conditions at the solid–gas interface, an effective diffusion coefficient was evaluated from experimental drying curves obtained in a moisture chamber. The effect of taking into account more than one term in the Fourier series solution was analysed and it is concluded that the diffusion coefficient corresponding to two terms in the series leads to better agreement with the experimental results for short times. 相似文献
17.
Lavelli V 《Journal of agricultural and food chemistry》2002,50(26):7704-7708
The phenol content and antioxidant activity of extra virgin olive oils (EVOOs) differing in their origins and degradation degrees were studied. The o-diphenolic compounds typical of olive oil, namely, the oleuropein derivatives hydroxytyrosol (3',4'-dihydroxyphenylethanol, 3',4'-DHPEA), the dialdehydic form of elenolic acid linked to 3',4'-DHPEA (3',4'-DHPEA-EDA), and an isomer of oleuropein aglycon (3',4'-DHPEA-EA), were analyzed by HPLC. The antioxidant activity was studied by (a) the xanthine oxidase (XOD)/xanthine system, which generates superoxide radical and hydrogen peroxide; (b) the diaphorase (DIA)/NADH/juglone system, which generates superoxide radical and semiquinonic radical; and (c) the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) test. Results showed that EVOOs with a low degradation level (as evaluated by acidity, peroxide number, and spectroscopic indices K(232), K(270), and deltaK according to the EU Regulation) had a higher content of 3',4'-DHPEA-EDA and a lower content of 3',4'-DHPEA than oils having intermediate and advanced degradation levels. EVOOs with a low degradation degree were 3-5 times more efficient as DPPH scavengers and 2 times more efficient as inhibitors of the XOD-catalyzed reaction than oils with intermediate and advanced degradation levels. The DIA-catalyzed reaction was inhibited by EVOOs having low or intermediate degradation levels but not by the most degraded oils. 相似文献
18.
19.
Tadokoro S Shattil SJ Eto K Tai V Liddington RC de Pereda JM Ginsberg MH Calderwood DA 《Science (New York, N.Y.)》2003,302(5642):103-106
Control of integrin affinity for ligands (integrin activation) is essential for normal cell adhesion, migration, and assembly of an extracellular matrix. Integrin activation is usually mediated through the integrin beta subunit cytoplasmic tail and can be regulated by many different biochemical signaling pathways. We report that specific binding of the cytoskeletal protein talin to integrin beta subunit cytoplasmic tails leads to the conformational rearrangements of integrin extracellular domains that increase their affinity. Thus, regulated binding of talin to integrin beta tails is a final common element of cellular signaling cascades that control integrin activation. 相似文献
20.
Muccilli V Lo Bianco M Cunsolo V Saletti R Gallo G Foti S 《Journal of agricultural and food chemistry》2011,59(22):12226-12237
The primary structures of high molecular weight glutenin subunits (HMW-GS) of 5 Triticum durum Desf. cultivars (Simeto, Svevo, Duilio, Bronte, and Sant'Agata), largely cultivated in the south of Italy, and of 13 populations of the old spring Sicilian durum wheat landrace Timilia (Triticum durum Desf.) (accession nos. 1, 2, 3, 4, 7, 8, 9, 13, 14, 15, SG1, SG2, and SG3) were investigated using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and reversed-phase high performance liquid chromatography/nanoelectrospray ionization mass spectrometry (RP-HPLC/nESI-MS/MS). M(r) of the intact proteins determined by MALDI mass spectrometry showed that all the 13 populations of Timilia contained the same two HMW-GS with 75.2 kDa and 86.4 kDa, whereas the other durum wheat cultivars showed the presence of the expected HMW-GS 1By8 and 1Bx7 at 75.1 kDa and 83.1 kDa, respectively. By MALDI mass spectrometry of the tryptic digestion peptides of the isolated HMW-GS of Timilia, the 1Bx and 1By subunits were identified as the NCBInr Acc. No AAQ93629, and AAQ93633, respectively. Sequence verification for HMW-GS 1Bx and 1By both in Simeto and Timilia was obtained by MALDI mass mapping and HPLC/nESI-MSMS of the tryptic peptides. The Bx subunit of Timila presents a sequence similarity of 96% with respect to Simeto, with differences in the insertion of 3 peptides of 5, 9, and 15 amino acids, for a total insertion of 29 amino acids and 25 amino acid substitutions. These differences in the amino acidic sequence account for the determined Δm of 3294 Da between the M(r) of the 1Bx subunits in Timilia and Simeto. Sequence alignment between the two By subunits shows 10 amino acid substitutions and is consistent with the Δm of 148 Da found in the MALDI mass spectra of the intact subunits. 相似文献