全文获取类型
收费全文 | 1050篇 |
免费 | 45篇 |
专业分类
林业 | 15篇 |
农学 | 10篇 |
基础科学 | 4篇 |
79篇 | |
综合类 | 470篇 |
农作物 | 14篇 |
水产渔业 | 4篇 |
畜牧兽医 | 463篇 |
园艺 | 2篇 |
植物保护 | 34篇 |
出版年
2012年 | 53篇 |
2011年 | 68篇 |
2010年 | 7篇 |
2009年 | 6篇 |
2008年 | 63篇 |
2007年 | 56篇 |
2006年 | 56篇 |
2005年 | 60篇 |
2004年 | 67篇 |
2003年 | 51篇 |
2002年 | 56篇 |
2001年 | 47篇 |
2000年 | 60篇 |
1999年 | 29篇 |
1998年 | 6篇 |
1997年 | 5篇 |
1995年 | 8篇 |
1994年 | 9篇 |
1993年 | 10篇 |
1992年 | 6篇 |
1991年 | 14篇 |
1990年 | 11篇 |
1989年 | 9篇 |
1988年 | 8篇 |
1987年 | 7篇 |
1986年 | 5篇 |
1985年 | 7篇 |
1984年 | 5篇 |
1983年 | 6篇 |
1982年 | 15篇 |
1981年 | 7篇 |
1979年 | 5篇 |
1976年 | 4篇 |
1971年 | 4篇 |
1970年 | 4篇 |
1969年 | 5篇 |
1968年 | 4篇 |
1967年 | 5篇 |
1963年 | 4篇 |
1955年 | 4篇 |
1954年 | 4篇 |
1942年 | 3篇 |
1899年 | 8篇 |
1898年 | 47篇 |
1897年 | 45篇 |
1896年 | 38篇 |
1895年 | 22篇 |
1893年 | 3篇 |
1892年 | 8篇 |
1885年 | 4篇 |
排序方式: 共有1095条查询结果,搜索用时 31 毫秒
11.
12.
13.
Malignant catarrhal fever was diagnosed in a newly imported swamp buffalo calf. This disease is prevalent in deer and cattle in New Zealand and causes sporadic losses in these species. The disease is recognised as a problem in buffaloes overseas and this paper records the first case in a swamp buffalo in New Zealand. 相似文献
14.
Freeman RG Grabar KC Allison KJ Bright RM Davis JA Guthrie AP Hommer MB Jackson MA Smith PC Walter DG Natan MJ 《Science (New York, N.Y.)》1995,267(5204):1629-1632
The self-assembly of monodisperse gold and silver colloid particles into monolayers on polymer-coated substrates yields macroscopic surfaces that are highly active for surface-enhanced Raman scattering (SERS). Particles are bound to the substrate through multiple bonds between the colloidal metal and functional groups on the polymer such as cyanide (CN), amine (NH(2)), and thiol (SH). Surface evolution, which can be followed in real time by ultraviolet-visible spectroscopy and SERS, can be controlled to yield high reproducibility on both the nanometer and the centimeter scales. On conducting substrates, colloid monolayers are electrochemically addressable and behave like a collection of closely spaced microelectrodes. These favorable properties and the ease of monolayer construction suggest a widespread use for metal colloid-based substrates. 相似文献
15.
16.
17.
18.
19.
Levine DG Smith JJ Richardson DW Brown V Beech J Habecker P Adam E 《Journal of the American Veterinary Medical Association》2007,231(3):437-441
CASE DESCRIPTION: A 6-month-old male Bactrian camel was examined because of a 3-week history of lameness of the left hind limb. CLINICAL FINDINGS: Lameness was initially detected in the left hind limb but resolved and was detected in the right hind limb during treatment. Lameness increased during periods of rapid growth. Radiography revealed multiple small opacities of the medullary cavity of several long bones throughout treatment. Core bone biopsies of lesions in the tibiae revealed lamellar bone with areas of loose connective tissue, osteoblasts in the medullary cavity, and periosteal new bone formation, all which were consistent with panosteitis. TREATMENT AND OUTCOME: Palliative treatment was attempted with epidural and transdermal administration of analgesics. Flunixin meglumine was administered PO, which coincided with an abrupt increase in serum creatinine concentration. Performance of multiple diagnostic bone biopsies led to remission of clinical signs of pain. CLINICAL RELEVANCE: Panosteitis should be a differential diagnosis for shifting limb lameness in young camels. Bone biopsies can be useful for diagnosis of panosteitis and possible relief of pain associated with the disease. Bactrian camels may be susceptible to the renal toxicity of flunixin meglumine, especially when dehydrated. 相似文献
20.
Five New World camelids were admitted to the Western College of Veterinary Medicine between 1996 and 2003 for evaluation of femoral fractures. There were three alpacas and two llamas. Four of the animals were female and three were less than 3 months of age. Fracture configurations consisted of distal physeal fractures (three), a comminuted diaphyseal/metaphyseal fracture, and a transverse diaphyseal fracture. Fractures were diagnosed with a combination of physical examination and radiographs in all cases. All five fractures were repaired with internal fixation and three animals were discharged from the hospital with fractures that healed. One cria underwent successful internal fixation but died from pulmonary oedema during recovery from anaesthesia. Postoperative complications were rare and limited to inadequate fracture stability in one alpaca and prolonged recovery to weight bearing in another. One llama with a comminuted metaphyseal fracture, repaired with a 4.5 mm dynamic compression plate, subsequently had catastrophic failure of the bone 17 days after surgery. Overall the clients were pleased with the outcome of discharged animals. Although femoral fractures are considered rare, they pose a unique opportunity for the large animal veterinarian to successfully achieve fracture union with the aid of internal fixation. 相似文献