全文获取类型
收费全文 | 1536篇 |
免费 | 88篇 |
国内免费 | 3篇 |
专业分类
林业 | 183篇 |
农学 | 55篇 |
基础科学 | 8篇 |
315篇 | |
综合类 | 219篇 |
农作物 | 73篇 |
水产渔业 | 121篇 |
畜牧兽医 | 493篇 |
园艺 | 47篇 |
植物保护 | 113篇 |
出版年
2024年 | 2篇 |
2023年 | 9篇 |
2022年 | 20篇 |
2021年 | 55篇 |
2020年 | 52篇 |
2019年 | 43篇 |
2018年 | 42篇 |
2017年 | 49篇 |
2016年 | 46篇 |
2015年 | 50篇 |
2014年 | 40篇 |
2013年 | 58篇 |
2012年 | 130篇 |
2011年 | 127篇 |
2010年 | 63篇 |
2009年 | 59篇 |
2008年 | 128篇 |
2007年 | 99篇 |
2006年 | 98篇 |
2005年 | 102篇 |
2004年 | 80篇 |
2003年 | 70篇 |
2002年 | 57篇 |
2001年 | 22篇 |
2000年 | 16篇 |
1999年 | 15篇 |
1998年 | 14篇 |
1997年 | 7篇 |
1996年 | 6篇 |
1995年 | 9篇 |
1994年 | 6篇 |
1993年 | 7篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1978年 | 1篇 |
1967年 | 1篇 |
1965年 | 1篇 |
1960年 | 1篇 |
1955年 | 1篇 |
1940年 | 1篇 |
1929年 | 1篇 |
排序方式: 共有1627条查询结果,搜索用时 15 毫秒
1.
Marine Ollier Vincent Talle Anne‐Laure Brisset Zo Le Bihan Simon Duerr Marc Lemmens Ellen Goudemand Olivier Robert Jean‐Louis Hilbert Hermann Buerstmayr 《Plant Breeding》2019,138(1):69-81
Fusarium head blight (FHB) is a cereal disease of major importance responsible for yield losses and mycotoxin contaminations in grains. Here, we introduce a new measurement approach to quantify FHB severity on grains based on the evaluation of the whitened kernel surface (WKS) using digital image analysis. The applicability of WKS was assessed on two bread wheat and one triticale grain sample sets (265 samples). Pearson correlation coefficients between Fusarium‐damaged kernels (FDK) and WKS range from r = 0.77 to r = 0.81 and from r = 0.61 to r = 0.86 for the correlation between deoxynivalenol (DON) content and WKS. This new scoring method facilitates fast and reliable assessment of the resistance to kernel infection and shows significant correlation with mycotoxin content. WKS can be automated and does not suffer from the “human factor” inherent to visual scorings. As a low‐cost and fast approach, this method appears particularly attractive for breeding and genetic analysis of FHB resistance where typically large numbers of experimental lines need to be evaluated, and for which WKS is suggested as an alternative to visual FDK scorings. 相似文献
2.
Marc Govaerts Peter Verhaert Frans Jongejan Bruno M Goddeeris 《Veterinary parasitology》2002,104(2):103-117
The immunodominant 33/35kDa antigen of a Theileria isolate from West Java, Indonesia, was characterised and immuno-affinity purified by use of a monoclonal antibody, KUL-a4, and was shown to be representative of the T. orientalis/sergenti/buffeli group. The aminoterminal sequence of the purified 35kDa peptide (20 residues) was determined by automated Edman degradation and found to correspond to the predicted amino acid sequence of a prospective p33 gene previously sequenced from the same isolate. The cleavage site of a putative signal peptide was identified and conforms the (-3, -1) rule for signal peptidases. The existence of dimeric and trimeric forms of the p33/35 antigen is hypothesised from Western blot profiles. KUL-a4 appeared specific for the T. orientalis/sergenti/buffeli group. It did not recognise in indirect fluorescence antibody test (IFAT), intraerythrocytic bodies of Anaplasma marginale or piroplasms and schizonts of T. mutans, T. parva and T. annulata, whereas cattle antisera raised to these species showed cross-reactivity in IFAT. It however, appeared weakly cross-reactive in Western blot and ELISA, with the 34kDa piroplasm antigen of one T. annulata (Gharb) isolate. The present study indicates that the isolated antigen belongs to the p33/34 antigen family described within the T. sergenti/orientalis/buffeli group, and documents the group-specificity of one of its epitopes. 相似文献
3.
Luc Van Ham Marc Vandevelde Miek Desmidt Mulenda Tshamala Luc De Schaepdrijver Daniel Mattheeuws 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(4):290-292
A central axonopathy in 2 male and 1 female Scottish Terrier puppies from 3 different but related litters is reported. Clinical signs consisting of severe whole-body tremors and ataxia were first detected at the age of 10 to 12 weeks. They worsened with activity and excitement and diminished during rest or sleep. Two dogs also had paraparesis. In 1 dog the neurological deficits progressed over several months. Neuropathological examination revealed widespread axonal changes, vacuolation, and gliosis in the white matter of the central nervous system. 相似文献
4.
The heterogenicity of Cowdria ruminantium stocks: cross-immunity and serology in sheep and pathogenicity to mice 总被引:2,自引:0,他引:2
J L Du Plessis L Van Gas J A Olivier J D Bezuidenhout 《The Onderstepoort journal of veterinary research》1989,56(3):195-201
Ten stocks of Cowdria ruminantium (Ball 3, Breed, Comoro, Germishuys, Kümm, Kwanyanga, Mali, Mara, Nonile and Welgevonden) were compared from a cross-immunity, serological and mouse pathogenicity point of view. They were found to differ in varying degrees. Except for the Ball 3, Comoro and Germishuys stocks that were similar but not identical, there was no pattern in the antigenic diversity of the 10 stocks. The Welgevonden stock emerged as the stock that elicits an immunity against most of the South African stocks. The inability of the reference Ball 3 stock to protect sheep against no fewer than 6 other stocks questions the advisability of retaining this stock as the vaccine stock. The antigenic diversity of the 10 stocks could not be correlated with the antibody levels detected with the indirect fluorescent antibody test, since the sera against all 10 stocks reacted positively to the Kümm stock antigen and the variation in titres was not stock-related. 相似文献
5.
6.
Mouillot Florent Ratte Jean-Pierre Joffre Richard Moreno Jose Manuel Rambal Serge 《Landscape Ecology》2003,18(7):665-674
Based on recent needs to accurately understand fire regimes and post-fire vegetation resilience at a supra-level for carbon cycle studies, this article focusses on the coupled history of fire and vegetation pattern for 40 years on a fire-prone area in central Corsica (France). This area has been submitted since the beginning of the 20th century to land abandonment and the remaining land management has been largely controlled by frequent fires. Our objectives were to rebuild vegetation and fire maps in order to determine the factors which have driven the spatial and temporal distribution of fires on the area, what were the feed backs on the vegetation dynamics, and the long-term consequences of this inter-relationship. The results show a stable but high frequency of small fires, coupled with forest expansion over the study period. The results particularly illustrate the spatial distribution of fires according to topography and vegetation, leading to a strong contrast between areas never burnt and areas which have been burnt up to 7 times. Fires, when occuring, affect on average 9 to 12% of the S, SE and SW facing slopes (compared to only 2 to 5% for the N facing slopes), spread recurrently over ridge tops, affect all the vegetation types but reburn preferentially shrublands and grasslands. As these fire-proning parameters have also been shown to decrease the regeneration capacity of forests, this study highlights the needs in spatial studies (both in terms of fire spread and vegetation dynamic) to accurately apprehend vegetation dynamic and functionning in fire-prone areas.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
7.
Anna R M Gelzer Marc S Kraus 《Veterinary Clinics of North America: Small Animal Practice》2004,34(5):1127-44, vi
Atrial fibrillation (AF) is the most common clinically important arrhythmia in veterinary medicine. Electrical cardioversion of AF to sinus rhythm is feasible, but pharmacologic rate control is an effective and achievable treatment strategy for most veterinary patients. Recent human trials suggest that rate control and rhythm control are almost equally beneficial. Nevertheless, AF can be a challenging arrhythmia to manage, because most affected animal shave numerous other concurring problems associated with the underlying heart disease that dictate or influence the clinician's choice of treatment and monitoring strategy for each patient. 相似文献
8.
Marc Lemmens Hermann Buerstmayr Rudolf Krska Rainer Schuhmacher Heinrich Grausgruber Peter Ruckenbauer 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(3):299-308
Fusarium head blight (FHB) is an important disease of wheat, which can result in the contamination of grains with mycotoxins such as deoxynivalenol (DON). Artificial inoculation of flowering ears with conidial suspensions is widely used to study FHB diseases. Our goal was to compare four inoculation treatments in which a conidial suspension was sprayed on flowering ears and to study the effect of the application of moisture during kernel setting and filling with a mist-irrigation system. Ten wheat genotypes were inoculated with a DON-producing Fusarium culmorum strain. Inoculation treatments varied in time of application of the inoculum (morning or evening) and in the method of controlling humidity during inoculation (bagging or mist irrigation). A wet season was simulated with a mist-irrigation system, keeping the crop canopy wet for at least 26 days after flowering. The severity of FHB symptoms (area under disease progress curve (AUDPC)), yield loss and DON contamination in the grains were determined. AUDPC data obtained with the different inoculation treatments were highly correlated (r=0.85–0.95). Mist irrigation after inoculation resulted in a higher mean disease severity, but in a overall lower toxin contamination as compared to the non-irrigated treatments. Genotypic differences in DON accumulation were present: for one wheat line toxin contamination significantly increased when irrigated, while two genotypes accumulated significantly less toxin. The closest relationships (r=0.73–0.89) between the visual symptoms and the DON content were obtained under moderate mean infection pressure. This relation between visual symptoms and the DON content deteriorated at higher infection levels. 相似文献
9.
Trevor J. Gilliland Paolo Annicchiarico Bernadette Julier Marc Ghesquière 《Grass and Forage Science》2020,75(3):227-241
Herbage production is regarded as having environment-friendly credentials. However, as the ruminant production it supports is facing major challenges on sustainability, environmental footprint and human health concerns, EU herbage cultivar testing must contribute to the solutions. Before new cultivars can be sold in a member state (MS) and gain EU-wide marketing, they must pass official tests to prove they are both novel (distinct, uniform and stable, DUS) with improved value for cultivation and use (VCU). Herbage species present specific challenges, as their allogamy imposes a wide within-cultivar variation that adds complexity to DUS tests and their “value” is only realized in ruminant produce. Current VCU systems measure production, chemical composition and disease/stress tolerances, often on large numbers of candidate cultivars, but prohibitive labour costs and logistics mean that animal intake, ruminant output or environmental benefits cannot be measured directly. Furthermore, some candidate cultivars with proven superior VCU fail DUS even though the non-distinct comparison is with a significantly lower performing registered cultivar. To resolve these problem cases, a “vmDUS” distinctness tool is proposed, which uses molecular markers but conforms to UPOV-declared principles. A short overview of current grassland research shows smart proxy measures of animal value can easily and quickly be adopted into an integrated pan-European (EU-VCU) test network. The proposed EU-VCU scheme will reallocate test resources to conduct these additional tests by placing MS in data sharing collaborations, while retaining their national listing authority. The benefits to all stakeholders from adopting these new testing procedures are considered. 相似文献
10.
Lien VANDE MAELE Marc HEYNDRICKX Dominiek MAES Nele DE PAUW Maxime MAHU Marc VERLINDEN Freddy HAESEBROUCK An MARTEL Frank PASMANS Filip BOYEN 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):325-328
The antibacterial potential of organic acids and essential oil components against Brachyspira
hyodysenteriae, the causative pathogen of swine dysentery, was evaluated. Minimum inhibitory
concentrations (MIC) of 15 compounds were determined at pH 7.2 and pH 6.0, using a broth microdilution assay.
In addition, possible synergism was determined. MIC values for the three tested strains were similar. For
organic acids, MIC values at pH 6.0 were lower than at pH 7.2. B. hyodysenteriae was most
sensitive to cinnamaldehyde and lauric acid, with MIC values <1.5 mM. Most antibacterial effects of binary
combinations were additive, however, for thymol and carvacrol, synergism could be observed. In
vitro results demonstrate the antibacterial action of certain essential oil components and organic
acids against B. hyodysenteriae. 相似文献