全文获取类型
| 收费全文 | 1340篇 |
| 免费 | 69篇 |
| 国内免费 | 1篇 |
专业分类
| 林业 | 19篇 |
| 农学 | 11篇 |
| 基础科学 | 5篇 |
| 69篇 | |
| 综合类 | 517篇 |
| 农作物 | 12篇 |
| 水产渔业 | 49篇 |
| 畜牧兽医 | 683篇 |
| 园艺 | 8篇 |
| 植物保护 | 37篇 |
出版年
| 2018年 | 11篇 |
| 2016年 | 17篇 |
| 2015年 | 13篇 |
| 2014年 | 16篇 |
| 2013年 | 40篇 |
| 2012年 | 20篇 |
| 2011年 | 44篇 |
| 2010年 | 27篇 |
| 2009年 | 21篇 |
| 2008年 | 30篇 |
| 2007年 | 22篇 |
| 2006年 | 12篇 |
| 2005年 | 28篇 |
| 2004年 | 25篇 |
| 2003年 | 29篇 |
| 2002年 | 20篇 |
| 2001年 | 24篇 |
| 2000年 | 18篇 |
| 1999年 | 24篇 |
| 1998年 | 22篇 |
| 1997年 | 23篇 |
| 1996年 | 11篇 |
| 1995年 | 17篇 |
| 1994年 | 14篇 |
| 1993年 | 17篇 |
| 1992年 | 27篇 |
| 1991年 | 39篇 |
| 1990年 | 37篇 |
| 1989年 | 27篇 |
| 1988年 | 18篇 |
| 1987年 | 12篇 |
| 1986年 | 21篇 |
| 1985年 | 12篇 |
| 1984年 | 10篇 |
| 1983年 | 14篇 |
| 1980年 | 39篇 |
| 1979年 | 48篇 |
| 1978年 | 52篇 |
| 1977年 | 46篇 |
| 1976年 | 39篇 |
| 1975年 | 30篇 |
| 1974年 | 38篇 |
| 1973年 | 36篇 |
| 1972年 | 20篇 |
| 1971年 | 19篇 |
| 1970年 | 45篇 |
| 1969年 | 27篇 |
| 1968年 | 36篇 |
| 1967年 | 35篇 |
| 1966年 | 46篇 |
排序方式： 共有1410条查询结果，搜索用时 15 毫秒
21.
22.
Carter LJ 《Science (New York, N.Y.)》1978,200(4349):1469-1470
23.
24.
1. Eggs from hens of three strains were dropped on to a heavy, stiff, smooth, plane body with impact at the equator of the shell; the height of drop, hc, just sufficient to produce shell failure was measured and the corresponding impact velocity, vc, calculated.
2. A small but commercially important percentage of the well‐formed eggs of one strain cracked when hc was as low as 3–3 mm and vc 250 mm/s.
3. Characteristics of the egg found to affect hc and vc included the overall thickness of its shell, thickness of its weak inner shell layer and average shell curvature, all measured at the point of impact, and its weight; its age also had a small effect (additional to that mediated through loss of weight); so did the degree of shell ridging.
4. No effect of shell colour was found.
5. Shell damage was typically a single hair‐crack that ran either round the equator or towards a pole. 相似文献
25.
26.
27.
28.
Test data generated by ~60 accredited member laboratories of the American Association of Veterinary Laboratory Diagnosticians (AAVLD) is of exceptional quality. These data are captured by 1 of 13 laboratory information management systems (LIMSs) developed specifically for veterinary diagnostic laboratories (VDLs). Beginning ~2000, the National Animal Health Laboratory Network (NAHLN) developed an electronic messaging system for LIMS to automatically send standardized data streams for 14 select agents to a national repository. This messaging enables the U.S. Department of Agriculture to track and respond to high-consequence animal disease outbreaks such as highly pathogenic avian influenza. Because of the lack of standardized data collection in the LIMSs used at VDLs, there is, to date, no means of summarizing VDL large data streams for multi-state and national animal health studies or for providing near-real-time tracking for hundreds of other important animal diseases in the United States that are detected routinely by VDLs. Further, VDLs are the only state and federal resources that can provide early detection and identification of endemic and emerging zoonotic diseases. Zoonotic diseases are estimated to be responsible for 2.5 billion cases of human illness and 2.7 million deaths worldwide every year. The economic and health impact of the SARS-CoV-2 pandemic is self-evident. We review here the history and progress of data management in VDLs and discuss ways of seizing unexplored opportunities to advance data leveraging to better serve animal health, public health, and One Health. 相似文献
29.