全文获取类型
收费全文 | 323篇 |
免费 | 16篇 |
专业分类
林业 | 32篇 |
农学 | 8篇 |
基础科学 | 5篇 |
85篇 | |
综合类 | 16篇 |
农作物 | 21篇 |
水产渔业 | 21篇 |
畜牧兽医 | 101篇 |
园艺 | 17篇 |
植物保护 | 33篇 |
出版年
2023年 | 3篇 |
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 6篇 |
2019年 | 8篇 |
2018年 | 5篇 |
2017年 | 3篇 |
2016年 | 14篇 |
2015年 | 5篇 |
2014年 | 16篇 |
2013年 | 13篇 |
2012年 | 27篇 |
2011年 | 32篇 |
2010年 | 13篇 |
2009年 | 15篇 |
2008年 | 26篇 |
2007年 | 26篇 |
2006年 | 11篇 |
2005年 | 19篇 |
2004年 | 11篇 |
2003年 | 18篇 |
2002年 | 17篇 |
2001年 | 11篇 |
2000年 | 4篇 |
1999年 | 5篇 |
1998年 | 4篇 |
1997年 | 5篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1993年 | 4篇 |
1991年 | 2篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1981年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有339条查询结果,搜索用时 31 毫秒
81.
82.
Breyer J Wemheuer WM Wrede A Graham C Benestad SL Brenig B Richt JA Schulz-Schaeffer WJ 《Veterinary microbiology》2012,157(1-2):23-31
Prion diseases are diagnosed by the detection of their proteinase K-resistant prion protein fragment (PrP(Sc)). Various biochemical protocols use different detergents for the tissue preparation. We found that the resistance of PrP(Sc) against proteinase K may vary strongly with the detergent used. In our study, we investigated the influence of the most commonly used detergents on eight different TSE agents derived from different species and distinct prion disease forms. For a high throughput we used a membrane adsorption assay to detect small amounts of prion aggregates, as well as Western blotting. Tissue lysates were prepared using DOC, SLS, SDS or Triton X-100 in different concentrations and these were digested with various amounts of proteinase K. Detergents are able to enhance or diminish the detectability of PrP(Sc) after proteinase K digestion. Depending on the kind of detergent, its concentration - but also on the host species that developed the TSE and the disease form or prion type - the detectability of PrP(Sc) can be very different. The results obtained here may be helpful during the development or improvement of a PrP(Sc) detection method and they point towards a detergent effect that can be additionally used for decontamination purposes. A plausible explanation for the detergent effects described in this article could be an interaction with the lipids associated with PrP(Sc) that may stabilize the aggregates. 相似文献
83.
Analyses of recent classical swine fever (CSF) epidemics in the European Union have shown that silent circulation of CSF virus (CSFV) occurs before the first outbreak is detected and this may lead to a large epidemic. However, severity of CSF disease signs may be linked with efficacy of disease transmission, the most severely affected animals having a higher infectivity than the less affected ones. The purpose of this study was to combine disease transmission quantification methods with CSF clinical signs quantification tools to investigate whether clinical signs, considered as infectivity markers, may allow us to calculate reliable estimates for disease transmission parameters. Data from three transmission experiments were used, varying according to the viral strain (Eystrup or Paderborn) and to the contact structure between experimentally inoculated and contact animals (direct or indirect contact). Within- and between-pen basic reproduction ratios (R0) were compared using viraemia data or clinical data. Between-pen R0 estimates were close and not significantly >1, with either strain or computation mode (using viraemia or clinical data). Conversely, within-pen R0s (Paderborn strain) computed using clinical data appeared higher than the estimates obtained using viraemia data. A models comparison (Bayes information criterion) showed a better fit of the clinical-based models, for both strains. This suggests that, in affected herds, the most severely affected animals could play a prominent role in CSFV transmission. 相似文献
84.
85.
Comparison of sandy soils suppressive or conducive to ectoparasitic nematode damage on sugarcane 总被引:1,自引:0,他引:1
ABSTRACT Two South African sandy soils, one suppressive and the other conducive to ectoparasitic nematode damage on monoculture sugarcane, were compared. Analysis of field transects indicated that the suppressive soil displayed a comparatively higher population of the weak ectoparasite Helicotylenchus dihystera, whose predominance among ectoparasitic nematodes is known to limit yield loss caused by more virulent phytonematodes. Soil type was identical at both sites (entisols), but the suppressive soil had a higher organic matter content and a lower pH, which correlated with H. dihystera population data. In contrast, microclimatic differences between the two field sites were unlikely to be responsible for the suppressive or conducive status of the soils, as shown in a greenhouse experiment. The two soils exhibited a bacterial community of the same size but with different genetic structures, as indicated by automated ribosomal intergenic spacer analysis (RISA). The number of culturable fluorescent pseudomonads was higher for the conducive soil, probably because extensive root damage caused by ectoparasitic nematodes favored proliferation of these bacteria. This study shows that apparently small differences in soil composition between fields located in the same climatic area and managed similarly can translate into contrasted nematode communities, ectoparasitic nematode damage levels, and sugarcane yields. 相似文献
86.
The Brucella genome at the beginning of the post-genomic era 总被引:1,自引:0,他引:1
Michaux-Charachon S Jumas-Bilak E Allardet-Servent A Bourg G Boschiroli ML Ramuz M O'Callaghan D 《Veterinary microbiology》2002,90(1-4):581-585
The year 2002 began with the publication of the first complete genome sequence for a Brucella species, that of the two replicons of B. melitensis 16M. Hopefully in 2002, the complete genome of B. suis 1330, and, perhaps, a B. abortus strain will be published. This is the culmination of over 30 years investigation of the composition, structure, organisation and evolution of the Brucella genome. Brucella research must now adapt to the new challenges of the post-genomic era. 相似文献
87.
Single-step purification and evaluation of recombinant BP26 protein for serological diagnosis of Brucella ovis infection in rams 总被引:1,自引:0,他引:1
Zygmunt MS Baucheron S Vizcaino N Bowden RA Cloeckaert A 《Veterinary microbiology》2002,87(3):213-220
To investigate the value of the BP26 protein in the serological diagnosis of ovine brucellosis caused by Brucella ovis, recombinant BP26 protein was produced in Echerichia coli and purified for use in an indirect enzyme-linked immunosorbent assay (I-ELISA). The majority of the recombinant protein was recovered from the supernatant of sonicated recombinant E. coli cells in a soluble form. This facilitated the purification of the recombinant BP26 protein which was achieved by using ion-exchange chromatography. After one step of purification, the purity of the recombinant BP26 protein was analyzed by using SDS-PAGE, Coomassie blue staining, and Western blot with a monoclonal antibody (MAb) directed against the BP26 protein. The degree of purity appeared satisfactory so that it could be directly used in I-ELISA. Although the recombinant BP26-ELISA appeared less useful than I-ELISA using the B. ovis hot saline (HS) extract as antigen, the high number of sera from B. ovis infected rams found positive (90%) in the recombinant BP26-I-ELISA indicated that the BP26 protein may be an additional suitable antigen for serological diagnosis of B. ovis infection in rams. 相似文献
88.
89.
Van de Maele I Savary-Bataille K Gielen I Daminet S 《The Canadian veterinary journal. La revue veterinaire canadienne》2008,49(3):283-286
An Akita Inu, living in Belgium, was presented with unusual clinical manifestations of acute babesiosis that included neurological signs and pancytopenia. Diagnosis was made by identifying Babesia canis in the blood smear. Neurological signs resolved after treatment with imidocarb diproprionate. Normalization of hematological abnormalities was gradual over 5 months. 相似文献
90.
Lecollinet S Richardson J 《Comparative immunology, microbiology and infectious diseases》2008,31(2-3):167-190
Natural infection of domestic cats by the feline immunodeficiency virus (FIV) causes acquired immunodeficiency syndrome (AIDS). FIV is genetically related to human immunodeficiency virus (HIV), and the clinical and biological features of infections caused by feline and human viruses in their respective hosts are highly analogous. Although the obstacles to vaccinating against FIV and HIV would seem to be of comparable difficulty, a licensed vaccine against feline AIDS is already in widespread use in several countries. While this seemingly major advance in prevention of AIDS would appear to be highly instructive for HIV vaccine development, its message has not been heeded by investigators in the HIV field. This review endeavours to relate what has been learned about vaccination against feline AIDS, and to suggest what this may mean for HIV vaccine development. 相似文献