全文获取类型
收费全文 | 166篇 |
免费 | 10篇 |
专业分类
林业 | 14篇 |
农学 | 7篇 |
35篇 | |
综合类 | 18篇 |
农作物 | 10篇 |
水产渔业 | 12篇 |
畜牧兽医 | 61篇 |
园艺 | 2篇 |
植物保护 | 17篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 5篇 |
2020年 | 4篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 5篇 |
2015年 | 5篇 |
2014年 | 5篇 |
2013年 | 12篇 |
2012年 | 18篇 |
2011年 | 19篇 |
2010年 | 7篇 |
2009年 | 6篇 |
2008年 | 10篇 |
2007年 | 8篇 |
2006年 | 9篇 |
2005年 | 12篇 |
2004年 | 6篇 |
2003年 | 5篇 |
2002年 | 5篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1987年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1969年 | 1篇 |
1966年 | 1篇 |
1955年 | 1篇 |
1950年 | 1篇 |
1949年 | 1篇 |
排序方式: 共有176条查询结果,搜索用时 15 毫秒
91.
Stuart J Rowland Mark Nixon Matthew Landos Charlie Mifsud Phil Read & Peter Boyd 《Aquaculture Research》2006,37(9):869-876
Infestations of parasitic monogenean trematodes (Lepidotrema bidyana and Gyrodactylus sp.) on freshwater silver perch (Bidyanus bidyanus Mitchell) in earthen ponds were treated with formalin (37% formaldehyde). Concentrations of 30 and 40 mg L?1 formalin were effective, but fish in ponds treated with 20 or 25 mg L?1 remained infested. At temperatures of 24.1–26.9°C, concentrations of 30 or 40 mg L?1 formalin caused dissolved oxygen (DO) to decline from 10.1–11.9 to 3.0–3.3 and 1.2–1.7 mg L?1, respectively, within 36–42 h of treatment. In addition, pH declined from 7.2–8.4 to 6.3–6.7, within 36 h and turbidity decreased over 48 h. In the ponds where DO was 1.2–1.7 mg L?1, silver perch showed signs of severe stress, but continuous aeration (10 hp ha?1) for 3 days and inflow of well‐oxygenated water for 6–8 h prevented mortalities. At temperatures of 13.2–15.7°C, concentrations of 30 or 40 mg L?1 formalin caused DO to decline from 9.0–10.0 to 6.0–8.1 mg L?1 and pH from 7.0–7.3 to 5.9–6.6 within 72 h. Total ammonia‐nitrogen increased over 72 h in ponds treated with 30 or 40 mg L?1 formalin. Fish became re‐infested with L. bidyana in all ponds within 30 days of treatment. A concentration of 30 mg L?1 formalin is recommended as a treatment for monogeneans on silver perch in ponds, but aeration is necessary to maintain adequate water quality at higher temperatures. 相似文献
92.
93.
Daniel C. Dauwalter Antonino Duchi John Epifanio Andrea Gandolfi Robert Gresswell Francis Juanes Jeffrey Kershner Javier Lobón-Cerviá Philip McGinnity Andreas Meraner Pavel Mikheev Kentaro Morita Clint C. Muhlfeld Kurt Pinter John R. Post Günther Unfer Leif Asbjørn Vøllestad Jack E. Williams 《Ecology of Freshwater Fish》2020,29(3):429-432
94.
This study investigates polyacrylonitile(PAN) fibers stabilized with various doses of electron beam irradiation (EBI) ability to produce carbon fibers. Feasibility was verified by FT-IR, the percent of gel fraction, density, DSC, XRD, and mechanical measurements. FT-IR spectra showed that the intensities of the stretching C??N bonds decreased at 2,244 cm?1 with increasing EBI dose. This de crease was related to cyclization of nitrile groups during EBI-stabilization. The degree of cyclization was determined from the gel fraction and density tests. The gel content and density of PAN fibers stabilized by EBI increased with an increase in the EBI dose. Thermal properties were characterized by differential scanning calorimetry (DSC) and thermally activated reactions. DSC curves showed that EBI treatment influenced the quantity of released heat and the exothermic position at low temperature over a wide temperature range. The strongest diffraction peak from the PAN precursor fiber arose from the (100) plane; its stabilization index (SI) was evaluated by X-ray diffraction. The X-ray results showed that the peak intensity decreases gradually with increasing EBI dose. In addition, tensile strength decreased the EBI stabilization level. 相似文献
95.
Jung Dae Lim Sung Ryul Lee Taeseong Kim Seon-A Jang Se Chan Kang Hyun Jung Koo Eunsoo Sohn Jong Phil Bak Seung Namkoong Hyoung Kyu Kim In Sung Song Nari Kim Eun-Hwa Sohn Jin Han 《Marine drugs》2015,13(2):1051-1067
Fucoidan is an l-fucose-enriched sulfated polysaccharide isolated from brown algae and marine invertebrates. In this study, we investigated the protective effect of fucoidan from Fucus vesiculosus on alcohol-induced murine liver damage. Liver injury was induced by oral administration of 25% alcohol with or without fucoidan (30 mg/kg or 60 mg/kg) for seven days. Alcohol administration increased serum aspartate aminotransferase and alanine aminotransferase levels, but these increases were suppressed by the treatment of fucoidan. Transforming growth factor beta 1 (TGF-β1), a liver fibrosis-inducing factor, was highly expressed in the alcohol-fed group and human hepatoma HepG2 cell; however, the increase in TGF-β1 expression was reduced following fucoidan administration. Treatment with fucoidan was also found to significantly reduce the production of inflammation-promoting cyclooygenase-2 and nitric oxide, while markedly increasing the expression of the hepatoprotective enzyme, hemeoxygenase-1, on murine liver and HepG2 cells. Taken together, the antifibrotic and anti-inflammatory effects of fucoidan on alcohol-induced liver damage may provide valuable insights into developing new therapeutics or interventions. 相似文献
96.
97.
98.
99.
Mitochondrial DNA short tandem repeats unveil hidden population structuring and migration routes of an endangered marine turtle 下载免费PDF全文
Yaron Tikochinski Phil Bradshaw Angela Mastrogiacomo Annette Broderick Alon Daya Andreas Demetropoulos Simon Demetropoulos Nicolas‐George Eliades Wayne Fuller Brendan Godley Yakup Kaska Yaniv Levy Robin Snape Lucy Wright Carlos Carreras 《水产资源保护:海洋与淡水生态系统》2018,28(4):788-797
100.