全文获取类型
收费全文 | 615篇 |
免费 | 36篇 |
专业分类
林业 | 106篇 |
农学 | 19篇 |
基础科学 | 2篇 |
86篇 | |
综合类 | 95篇 |
农作物 | 24篇 |
水产渔业 | 33篇 |
畜牧兽医 | 254篇 |
园艺 | 2篇 |
植物保护 | 30篇 |
出版年
2021年 | 7篇 |
2020年 | 8篇 |
2019年 | 7篇 |
2018年 | 12篇 |
2017年 | 9篇 |
2016年 | 10篇 |
2015年 | 7篇 |
2014年 | 15篇 |
2013年 | 14篇 |
2012年 | 30篇 |
2011年 | 27篇 |
2010年 | 18篇 |
2009年 | 15篇 |
2008年 | 29篇 |
2007年 | 36篇 |
2006年 | 25篇 |
2005年 | 16篇 |
2004年 | 16篇 |
2003年 | 10篇 |
2002年 | 19篇 |
2000年 | 9篇 |
1999年 | 10篇 |
1998年 | 9篇 |
1996年 | 7篇 |
1995年 | 6篇 |
1991年 | 8篇 |
1990年 | 6篇 |
1988年 | 6篇 |
1986年 | 10篇 |
1985年 | 11篇 |
1983年 | 9篇 |
1982年 | 8篇 |
1981年 | 6篇 |
1980年 | 7篇 |
1978年 | 7篇 |
1977年 | 7篇 |
1976年 | 5篇 |
1975年 | 6篇 |
1973年 | 7篇 |
1972年 | 16篇 |
1970年 | 5篇 |
1969年 | 8篇 |
1967年 | 6篇 |
1966年 | 12篇 |
1965年 | 6篇 |
1964年 | 7篇 |
1963年 | 5篇 |
1962年 | 5篇 |
1957年 | 7篇 |
1955年 | 6篇 |
排序方式: 共有651条查询结果,搜索用时 15 毫秒
91.
Dietrich U 《Clinical Techniques in Small Animal Practice》2005,20(2):108-116
Cats are usually presented at a very late stage in the course of glaucoma when the eye is already blind. Secondary glaucoma because of another underlying ocular lesion is the most common form of glaucoma in the cat and is frequently associated with chronic anterior uveitis or intraocular neoplasia. Chronic stages of glaucoma in the cat are characterized by buphthalmus, anterior lens luxation, and exposure keratitis secondary to the enlarged globe. Ophthalmoscopic signs of glaucomatous retinal degeneration are only noticed in very advanced stages. Treatment of glaucoma in cats is usually aimed to keep the eye comfortable and within a normal intraocular pressure range. However, many antiglaucoma medications that are successfully used in humans and dogs are not very well tolerated by cats and, therefore, the selection of recommended drugs is limited in this species. 相似文献
92.
Mayer MN LaRue SM 《The Canadian veterinary journal. La revue veterinaire canadienne》2005,46(11):1048, 1050, 1052
93.
Rüfenacht S Marti E von Tscharner C Doherr MG Forster U Welle M Roosje PJ 《Veterinary dermatology》2005,16(2):94-101
The pathogenesis of equine urticaria is not well understood. In man, urticaria has been associated with immunological and nonimmunological mechanisms leading to the release of various mediators by mast cells. Skin biopsies of 32 horses with a history of urticaria were stained with toluidine blue, a double-labelling method for chymase and tryptase, and immunohistochemistry for immunoglobulin (Ig)E. These horses were compared with horses with pemphigus foliaceus, insect bite hypersensitivity and control horses with healthy skin. Neither formalin fixation time nor biopsy site influenced the staining methods. No chymase-positive cells were found. In all groups of horses, cells staining with toluidine blue and for tryptase and IgE were found in the epidermis and hair follicle papilla and significantly more positively staining cells were observed in the subepidermal dermis compared with the deep dermis. Horses with urticaria had significantly more IgE-bearing cells in the subepidermal dermis than control horses. However, horses with urticaria had significantly fewer toluidine-blue-stained mast cells in both subepidermal and deep dermis compared with the insect bite hypersensitivity and pemphigus foliaceus groups. This study suggests that IgE-mediated reactions play a role in the pathogenesis of urticaria. 相似文献
94.
95.
B. Huber und H. Mayer 《Journal of pest science》1962,35(10):157
Ohne Zusammenfassung 相似文献
96.
Anaplasma infection in free-ranging Iberian red deer in the region of Castilla-La Mancha, Spain 总被引:4,自引:0,他引:4
De La Fuente J Vicente J Höfle U Ruiz-Fons F Fernández De Mera IG Van Den Bussche RA Kocan KM Gortazar C 《Veterinary microbiology》2004,100(3-4):163-173
Organisms in the genus Anaplasma are obligate intracellular pathogens that multiply in both vertebrate and invertebrate hosts. The type species, Anaplasma marginale, causes bovine anaplasmosis and infects erythrocytes of the vertebrate host and undergoes a complex developmental cycle in ticks which serve as biological vectors. Infected cattle, wild ruminants and ticks can all serve as reservoirs of A. marginale. In this study, hunter killed Iberian red deer (Cervus elaphus hispanicus) from the region of Castilla-La Mancha in southwestern Spain were tested for Anaplasma infection. We found that 10% of the deer examined were seropositive for Anaplasma. Three A. marginale strains were subsequently obtained from salivary glands of Hyalomma marginatum that were removed from these deer, and the sequence of the major surface protein (msp)4 gene was determined for each strain and used for phylogenetic studies. Maximum parsimony analyses of msp4 sequences from H. marginatum ticks in comparison with New World cattle and bison isolates reported previously, suggested different origins for these Spanish A. marginale strains. The results of this study demonstrated that Iberian red deer are naturally infected with Anaplasma, and may therefore serve as a wildlife reservoir of the pathogen. Although the link between deer infection and the strains of A. marginale identified in ticks was not established, H. marginatum and Rhipicephalus bursa were identified as potential biological vectors for A. marginale in this region and may effect transmission of A. marginale between deer and cattle populations. 相似文献
97.
98.
Salzmann CG Radaelli PG Hallbrucker A Mayer E Finney JL 《Science (New York, N.Y.)》2006,311(5768):1758-1761
Two hydrogen ordered phases of ice were prepared by cooling the hydrogen disordered ices V and XII under pressure. Previous attempts to unlock the geometrical frustration in hydrogen-bonded structures have focused on doping with potassium hydroxide and have had success in partially increasing the hydrogen ordering in hexagonal ice I (ice Ih). By doping ices V and XII with hydrochloric acid, we have prepared ice XIII and ice XIV, and we analyzed their structures by powder neutron diffraction. The use of hydrogen chloride to release geometrical frustration opens up the possibility of completing the phase diagram of ice. 相似文献
99.
100.