全文获取类型
| 收费全文 | 791篇 |
| 免费 | 26篇 |
| 国内免费 | 18篇 |
专业分类
| 林业 | 14篇 |
| 农学 | 9篇 |
| 基础科学 | 22篇 |
| 44篇 | |
| 综合类 | 287篇 |
| 农作物 | 18篇 |
| 水产渔业 | 18篇 |
| 畜牧兽医 | 392篇 |
| 园艺 | 15篇 |
| 植物保护 | 16篇 |
出版年
| 2024年 | 2篇 |
| 2023年 | 7篇 |
| 2022年 | 10篇 |
| 2021年 | 17篇 |
| 2020年 | 27篇 |
| 2019年 | 21篇 |
| 2018年 | 9篇 |
| 2017年 | 35篇 |
| 2016年 | 19篇 |
| 2015年 | 37篇 |
| 2014年 | 65篇 |
| 2013年 | 51篇 |
| 2012年 | 58篇 |
| 2011年 | 70篇 |
| 2010年 | 46篇 |
| 2009年 | 60篇 |
| 2008年 | 47篇 |
| 2007年 | 39篇 |
| 2006年 | 38篇 |
| 2005年 | 24篇 |
| 2004年 | 16篇 |
| 2003年 | 18篇 |
| 2002年 | 14篇 |
| 2001年 | 7篇 |
| 2000年 | 14篇 |
| 1999年 | 12篇 |
| 1998年 | 14篇 |
| 1997年 | 8篇 |
| 1996年 | 6篇 |
| 1995年 | 5篇 |
| 1994年 | 3篇 |
| 1993年 | 2篇 |
| 1992年 | 3篇 |
| 1991年 | 4篇 |
| 1990年 | 4篇 |
| 1989年 | 3篇 |
| 1988年 | 6篇 |
| 1987年 | 2篇 |
| 1985年 | 4篇 |
| 1984年 | 3篇 |
| 1983年 | 4篇 |
| 1980年 | 1篇 |
排序方式： 共有835条查询结果，搜索用时 312 毫秒
1.
The Eurasian wild boar (Sus scrofa) is a reservoir for tuberculosis (TB) in which vaccination is a valuable tool for control. We evaluated the protection and immune response achieved by homologous and heterologous regimes administering BCG and heat-inactivated Mycobacterium bovis (IV). Twenty-one wild boar piglets were randomly allocated in five groups: Control, homologous BCG, homologous IV, heterologous IV-BCG, heterologous BCG-IV. Significant 67% and 66% total lesion score reductions were detected in homologous IV (IVx2) and heterologous IV-BCG groups when compared with Control group (F4,16 = 6.393, p = 0.003; Bonferroni Control vs IVx2 p = 0.026, Tukey Control vs IV-BCG p = 0.021). No significant differences were found for homologous BCG (although a 48% reduction in total lesion score was recorded) and BCG-IV (3% reduction). Heterologous regimes did not improve protection over homologous regimes in the wild boar model and showed variable results from no protection to similar protection as homologous regimes. Therefore, homologous regimes remain the best option to vaccinate wild boar against TB. Moreover, vaccine sequence dramatically influenced the outcome underlining the relevance of studying the effects of prior sensitization in the outcome of vaccination. 相似文献
2.
生长季苹果硼素营养变化动态及诊断 总被引：4，自引：0，他引：4
田间条件下，玫瑰红／平邑甜茶新生器官全硼变化动态表现不同：短梢叶全硼含量较稳定；长梢叶及其皮部变化动态相似，生长季早期全硼下降，中期升高，后期又下降；果实全硼变化最大，随果实膨大，全硼持续降低，其中以花后一个月降低幅度最大。缺硼植株的果实及长梢皮部全硼显著降低，其它部位全硼含量与缺硼症表现程度之间不一致。果实采收后，长梢皮部全硼含量与次年幼果的全硼含量呈显著正相关。秋季干旱处理长梢皮部全硼含量下降幅度大于叶片和果实。长梢皮部可作为苹果硼素营养的诊断器官。 相似文献
3.
为了建立一种快速、简便、敏感、特异地检测动物病理材料中布氏杆菌的方法,选用四种标记抗体法,对5种共15个生物型的布氏杆菌,以及大量与流产有关或常常污染病理材料的对照细菌,分别进行了纯菌、感染实验动物及牦牛组织材料的染色检查,并与柯氏染色法及细菌分离培养法进行了比较。结果表明,四种方法对于各种材料中的布氏杆菌(粗糙型犬布氏菌除外)均呈阳性反应,而绝大多数对照菌均呈阴性反应。其中尤以SPA法染色背景更为清晰,非特异性反应更少。这些方法既简便、快速,检出率也较高。对于布氏杆菌病的诊断和疫情监测,是很有价值的。 相似文献
4.
5.
本试验对送检的金丝雀经实验室诊断，确认为金丝雀痘，对分离的痘病毒进行动物致病性试验、病毒分离传代和致试验、致弱毒保护力试验和返强试验。结果表明：金丝雀痘病毒经鸡胚盲传３后能适鸡胚并致死金丝雀，８代后无致病性，１３例毒性快速通过本动物３次无返强现象，金丝雀用第１３代毒刺种３０天能抵抗强毒攻击。 相似文献
6.
陶元清 《青海畜牧兽医杂志》2005,35(4):20-20
以SPF级（无特殊病原体）动物为种源，采取综合防治措施，在屏障设施饲养清洁级实验小鼠和大鼠。经过两年饲养繁育的结果表明：动物微生物学质量符合清洁级动物国家标准，质量控制效果显著。 相似文献
7.
8.
Infrared thermography has been used to help in diagnosing lameness. It is hypothesized that, if used in a routine basis, it could help in understanding musculoskeletal modifications during race training. This study aimed to evaluate thermal variation in the musculoskeletal regions of young Thoroughbred (TB) horses during their initial months of race training. Thermographic examinations were performed once every 2 weeks on 16 (10 male, 6 female) two-year-old TB racehorses, from arrival to the racetrack in June 2016, until January 2017, for a total of 16 evaluations. Thermographic imaging was performed using the appropriate protocol. Temperature (°C) was measured at the dorsal and palmar/plantar aspects of specific regions of interest (fetlock, metacarpal, metatarsal, carpal, tarsal, thoracolumbar, sacroiliac spine, and both hips). Initially, we found a thermal balance and all regions demonstrated a positive correlation with one another. However, a significant difference was noted between the left and right sides as training progressed. Four horses were withdrawn from the study after 50% of evaluations because of metacarpal conditions associated with training. Thermographic examination revealed changes before the clinical manifestation of these conditions. In conclusion, this study demonstrated that infrared thermography is an image technique that can facilitate understanding of musculoskeletal system modifications to race training and should be further investigated as a predictive tool to anticipate the occurrence of lesions. 相似文献
9.
10.