全文获取类型
收费全文 | 180篇 |
免费 | 16篇 |
专业分类
林业 | 8篇 |
农学 | 3篇 |
基础科学 | 1篇 |
18篇 | |
综合类 | 18篇 |
农作物 | 3篇 |
水产渔业 | 4篇 |
畜牧兽医 | 126篇 |
园艺 | 7篇 |
植物保护 | 8篇 |
出版年
2023年 | 3篇 |
2021年 | 3篇 |
2020年 | 12篇 |
2019年 | 6篇 |
2018年 | 7篇 |
2017年 | 6篇 |
2016年 | 8篇 |
2015年 | 6篇 |
2014年 | 9篇 |
2013年 | 15篇 |
2012年 | 15篇 |
2011年 | 13篇 |
2010年 | 8篇 |
2009年 | 6篇 |
2008年 | 14篇 |
2007年 | 18篇 |
2006年 | 7篇 |
2005年 | 4篇 |
2004年 | 8篇 |
2003年 | 6篇 |
2002年 | 5篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1989年 | 2篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有196条查询结果,搜索用时 156 毫秒
1.
2.
Plasma N‐terminal pro‐B‐type natriuretic peptide concentration in healthy retired racing Greyhounds 下载免费PDF全文
3.
Seunghan Lee Vikas Kumar Beth Cleveland Nicholas Romano Goutham N Vemuri Amit K. Yadav Kristen Meiler Ronald W. Hardy 《Aquaculture Research》2020,51(10):4065-4074
The rapid global growth in fish farming and limited supply of fish meal (FM) has consequently reduced FM inclusion levels in compound feeds leading to a higher reliance on alternative protein sources. Sasya is a single cell protein (SCP) product that has a similar amino acid profile as FM. The aim of this study was to evaluate the effects of replacing FM with SCP on in vivo digestibility, growth, feed efficiency, whole‐body proximate/amino acid composition and gene expression levels of various hepatic enzymes in rainbow trout (Oncorhynchus mykiss). Three isonitrogenous (470 g/kg crude protein) and isolipidic (18 g/kg crude lipid) diets were formulated as follows: Diet 1: control (30% FM); Diet 2:24% FM + 6% SCP and Diet 3:18% FM + 12% SCP. Each diet was hand‐fed to triplicate tanks containing 30 rainbow trout fingerlings (4.99 ± 0.20 g) for 9 weeks. Apparent digestibility coefficients of SCP for dry matter, crude protein, lipid and energy were 60, 80, 93 and 74% respectively. Growth performance (final weight: 69–71 g), feed conversion ratios (0.91–0.94) as well as whole‐body protein and amino acid composition were unaffected by diets. However, Diet 3 significantly increased whole‐body crude fat and energy. Fish fed the SCP‐based diets had significantly higher expression for carnitine palmitoyltransferase‐1b (CPT1b), fatty acid delta 6 desaturase (FADS6) and fatty acid elongase 5 compared to the control. Overall, the quality of the SCP was similar as FM. Therefore, this product could enlarge the portfolio of alternative protein sources that can be used in fish diets and thus open a new market opportunity for use of a new feed resource in the feed industry. 相似文献
4.
5.
6.
K. Jane Wardrop DVM MS Russell L. Tucker Kristen Mugnai 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(1):5-8
An additive solution for the storage of red blood cells was evaluated for use in dogs. Blood collected from 6 dogs was processed into packed red blood cells and stored for 35 days in the additive solution Nutricel (Miles, Inc, Pharmaceutical Division, West Haven, CT). Packed red blood cells stored in citrate-phosphate-dextrose-adenine (CPDA-1; Fenwal Laboratories, Baxter Health Care Corp, Deerfield, IL) also were evaluated for comparison. Red blood cell 2,3-diphosphoglycerate (2,3-DPG) concentration, adenosine triphosphate (ATP) concentration, percentage hemolysis, and pH were determined. The red blood cell post-transfusion viability (PTV) after 35 days of storage was assessed with both single-labeled chromium 51 (51Cr) and double-labeled technetium 99m/chromium 51 (99mTc/51Cr) techniques. Mean ATP concentration and percentage hemolysis of the cells stored in Nutricel were 1.1 μmol/g hemoglobin (Hb) and 0.28% respectively and did not differ significantly (P < .05) from the values of 1.0 μmol/g Hb and 0.33% from the CPDA-1-stored red blood cells. The mean pH of red blood cells stored in Nutricel was 6.19, which was significantly lower than the pH of 6.47 for cells stored in CPDA-1. The mean 2,3-DPG concentration of red blood cells stored in Nutricel was significantly higher at 10.1 μmol/g Hb than the 2,3-DPG concentration of 3.4μmol/g Hb for cells stored in CPDA-1. The mean PTV of canine red blood cells stored in Nutricel for 35 days was 85% with 51Cr and 90% with 99mTc/51Cr. This was significantly higher than the mean PTVs of 38% and 36% for the CPDA-1 stored cells as assessed with 51Cr and 99mTc/51Cr techniques, respectively. It was concluded that 35-day-old canine red blood cells stored in Nutricel are of acceptable quality for transfusion purposes. 相似文献
7.
Paige DA Siegler MA Zhang JA Hayne PO Foote EJ Bennett KA Vasavada AR Greenhagen BT Schofield JT McCleese DJ Foote MC DeJong E Bills BG Hartford W Murray BC Allen CC Snook K Soderblom LA Calcutt S Taylor FW Bowles NE Bandfield JL Elphic R Ghent R Glotch TD Wyatt MB Lucey PG 《Science (New York, N.Y.)》2010,330(6003):479-482
Diviner Lunar Radiometer Experiment surface-temperature maps reveal the existence of widespread surface and near-surface cryogenic regions that extend beyond the boundaries of persistent shadow. The Lunar Crater Observation and Sensing Satellite (LCROSS) struck one of the coldest of these regions, where subsurface temperatures are estimated to be 38 kelvin. Large areas of the lunar polar regions are currently cold enough to cold-trap water ice as well as a range of both more volatile and less volatile species. The diverse mixture of water and high-volatility compounds detected in the LCROSS ejecta plume is strong evidence for the impact delivery and cold-trapping of volatiles derived from primitive outer solar system bodies. 相似文献
8.
Kristen C. Nelson Rachel F. Brummel Nicholas Jordan Steven Manson 《Agriculture and Human Values》2014,31(2):245-259
Multifunctional agricultural systems seek to expand upon production-based benefits to enhance family wellbeing and animal health, reduce inputs, and improve environmental services such as biodiversity and water quality. However, in many countries a landscape-level conversion is uneven at best and stalled at worst. This is particularly true across the eastern rural landscape in the United States. We explore the role of social networks as drivers of system transformation within dairy production in the eastern United States, specifically rotational grazing as an alternative management option. We hypothesize the importance of weak ties within farmer social networks as drivers of change. In Wisconsin, Pennsylvania, and New York, we conducted 53 interviews with confinement, low-intensity, and rotational grazing dairy producers as well as 35 interviews with associated network actors. Though confinement and grazier networks had similar proportions of strong and weak ties, confinement producers had more market-based weak ties, while graziers had more weak-ties to government agencies and other graziers in the region. These agency weak ties supported rotational graziers through information exchange and cost sharing, both crucial to farmers’ transitions from confinement-based production to grazing systems. While weak ties were integral to initial innovation, farmers did not maintain these relationships beyond their transition to grazing. Of equal importance, grazier weak-tie networks did not include environmental organizations, suggesting unrealized potential for more diverse networks based on environmental services. By understanding the drivers, we can identify barriers to expanding weak tie networks and emergent properties in order to create institutions and policies necessary for change. 相似文献
9.
10.
Sarah A Reed Joseline S Raja Maria L Hoffman Steven A Zinn Kristen E Govoni 《畜牧与生物技术杂志(英文版)》2014,5(1):43