全文获取类型
收费全文 | 4455篇 |
免费 | 139篇 |
国内免费 | 217篇 |
专业分类
林业 | 217篇 |
农学 | 375篇 |
基础科学 | 18篇 |
217篇 | |
综合类 | 1188篇 |
农作物 | 407篇 |
水产渔业 | 23篇 |
畜牧兽医 | 204篇 |
园艺 | 1818篇 |
植物保护 | 344篇 |
出版年
2024年 | 10篇 |
2023年 | 55篇 |
2022年 | 113篇 |
2021年 | 124篇 |
2020年 | 197篇 |
2019年 | 109篇 |
2018年 | 215篇 |
2017年 | 246篇 |
2016年 | 277篇 |
2015年 | 312篇 |
2014年 | 248篇 |
2013年 | 255篇 |
2012年 | 342篇 |
2011年 | 328篇 |
2010年 | 277篇 |
2009年 | 217篇 |
2008年 | 201篇 |
2007年 | 158篇 |
2006年 | 142篇 |
2005年 | 120篇 |
2004年 | 77篇 |
2003年 | 73篇 |
2002年 | 96篇 |
2001年 | 75篇 |
2000年 | 76篇 |
1999年 | 82篇 |
1998年 | 61篇 |
1997年 | 44篇 |
1996年 | 45篇 |
1995年 | 31篇 |
1994年 | 41篇 |
1993年 | 23篇 |
1992年 | 42篇 |
1991年 | 19篇 |
1990年 | 20篇 |
1989年 | 19篇 |
1988年 | 15篇 |
1987年 | 6篇 |
1986年 | 10篇 |
1985年 | 2篇 |
1984年 | 4篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有4811条查询结果,搜索用时 31 毫秒
21.
22.
23.
《农业科学与技术》2016,(3):544-550
The morphological characters, physiological characters, yield traits and yield per plant of total 49 rice cultivars from Ningxia were investigated under conditions of water stress and non-water stress so as to determine the relationship between each trait and yield per plant under water stress and the relationship between each relative character and drought resistance coefficient under water stress and non-water stress. The correlation, grey correlation, stepwise regression and path analyses showed that the til er number per plant, plant height, grain density, effective panicle number per plant and grain number per pan-icle, total 5 traits, were significantly correlated with the drought resistance of rice, and they could be used to identify the drought resistance of rice in Ningxia. In addition, the drought resistance of rice was graded qualitatively according to the subordinate function value of corresponding drought resistance coefficient. The results showed that among the 49 rice cultivars from Ningxia, 6 rice cultivars were highly drought resistant, and 9 rice cultivars were moderately drought resistant, suggesting that the evalua-tion method was feasible and effective. 相似文献
24.
描述了毛竹的1个新栽培变种——绿槽龟甲竹。其竹秆下部一段的节交互歪斜,上下节在一侧相连,而节间在另一侧偏肿呈龟甲状,竹秆黄色,且龟甲状秆对称绿色纵条纹,分枝一侧纵沟槽绿色,叶片有淡黄色细纵条纹。 相似文献
25.
后备优质晚稻新品种引种试验 总被引:1,自引:0,他引:1
进行8个优质稻新品种的引种试验,试验结果表明:8个品种均表现米质优,有7个品种生育期适宜、适应性较广,可作为宁德市蕉城区优质稻后备品种继续试种。 相似文献
26.
27.
本文根据变量理论分布对区试中b值及CV值参数的数量分类,提出了适于目前普及推广的查表计算法。在此基础上,对区试品种提出了按主要生产性能指标以量定性的评定分类体系。从而推出可排除主观随意性干扰、较为完整严密的区试汇总模式,并以范例作了运用说明。 相似文献
28.
Bactericidal/permeability-increasing protein (BPI) has a strong effect on sterilization (mainly for G- bacteria),neutralizing the activity of lipopolysaccharide (LPS) and enhancing the phagocytosis of mononuclear cells and neutrophils to pathogenic bacteria.The biological functions of BPI have been researched widely in recent years,which is known as "super antibiotic" and has been explored by many scholars as a candidate gene for resistance.This author summarized the research progress and application prospect of the BPI gene in the pig resistant breeding by introducing the structure,biological function of BPI gene and its relationship with the resistance,which was aimed to provide theoretical references and basis for the function research of pig BPI gene and its practical application in resistance breeding in future. 相似文献
29.
Effects of thermo‐resistant non‐starch polysaccharide degrading multi‐enzyme on growth performance,meat quality,relative weights of body organs and blood profile in broiler chickens
下载免费PDF全文
![点击此处可从《Journal of animal physiology and animal nutrition》网站下载免费的PDF全文](/ch/ext_images/free.gif)
M. Mohammadi Gheisar A. Hosseindoust I. H. Kim 《Journal of animal physiology and animal nutrition》2016,100(3):499-505
This research was conducted to study the performance and carcass parameters of broiler chickens fed diets supplemented with heat‐treated non‐starch polysaccharide degrading enzyme. A total of 432 one‐day old Ross 308 broiler chickens were allocated to five treatments: (i) CON (basal diet), (ii) E1: CON + 0.05% multi‐enzyme, (iii) E2: CON + 0.1% multi‐enzyme, (iv) E3: CON + 0.05% thermo‐resistant multi‐enzyme and (v) E4: CON + 0.1% thermo‐resistant multi‐enzyme, each treatment consisted of six replications and 12 chickens in each replication. The chickens were housed in three floor battery cages during 28‐day experimental period. On days 1–7, gain in body weight (BWG) improved by feeding the diets supplemented with thermo‐resistant multi‐enzyme. On days 7–21 and 1–28, chickens fed the diets containing thermo‐resistant multi‐enzyme showed improved (p < 0.05) BWG and feed conversion ratio (FCR) compared to CON group. Supplementing the diets with multi‐enzyme or thermo‐resistant multi‐enzyme affected the percentage of drip loss on d 1 (p < 0.05). Drip loss percentage on days 3 and 5 and also meat colour were not affected significantly. Supplementing the diets with multi‐enzyme or thermo‐resistant multi‐enzyme did not affect the relative weights of organs but compared to CON group, relative weight of breast muscle increased and abdominal fat decreased (p < 0.05). Among measured blood constituents, chickens fed supplemented diets with thermo‐resistant multi‐enzyme showed higher (p < 0.05) IgG. Counts of red and white blood cells and lymphocyte percentage were not affected. In conclusion, the results demonstrated that supplementing pelleted diets with thermo‐resistant multi‐enzyme improved performance of broiler chickens. 相似文献
30.