全文获取类型
收费全文 | 11048篇 |
免费 | 673篇 |
国内免费 | 968篇 |
专业分类
林业 | 677篇 |
农学 | 695篇 |
基础科学 | 327篇 |
5117篇 | |
综合类 | 4002篇 |
农作物 | 341篇 |
水产渔业 | 202篇 |
畜牧兽医 | 602篇 |
园艺 | 230篇 |
植物保护 | 496篇 |
出版年
2024年 | 98篇 |
2023年 | 338篇 |
2022年 | 438篇 |
2021年 | 481篇 |
2020年 | 483篇 |
2019年 | 499篇 |
2018年 | 408篇 |
2017年 | 659篇 |
2016年 | 732篇 |
2015年 | 553篇 |
2014年 | 604篇 |
2013年 | 888篇 |
2012年 | 1031篇 |
2011年 | 794篇 |
2010年 | 566篇 |
2009年 | 555篇 |
2008年 | 484篇 |
2007年 | 536篇 |
2006年 | 501篇 |
2005年 | 425篇 |
2004年 | 288篇 |
2003年 | 225篇 |
2002年 | 168篇 |
2001年 | 158篇 |
2000年 | 128篇 |
1999年 | 101篇 |
1998年 | 93篇 |
1997年 | 80篇 |
1996年 | 69篇 |
1995年 | 58篇 |
1994年 | 37篇 |
1993年 | 40篇 |
1992年 | 38篇 |
1991年 | 38篇 |
1990年 | 22篇 |
1989年 | 19篇 |
1988年 | 19篇 |
1987年 | 17篇 |
1986年 | 9篇 |
1985年 | 4篇 |
1984年 | 1篇 |
1982年 | 2篇 |
1962年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Stefan Möth Markus Redl Silvia Winter Florian Hüttner Siegrid Steinkellner 《Pest management science》2023,79(9):3080-3089
BACKGROUND
A reduction in chasmothecia, an important inoculum of grape powdery mildew (Erysiphe necator Schwein.), is essential for disease control in vineyards; the use of fungicides during the formation of chasmothecia on vine leaves, late in the growing season, may accomplish this. Inorganic fungicides, such as sulphur, copper, and potassium bicarbonate, are very useful for this purpose because of their multisite mode of action. The aim of this study was to evaluate chasmothecia reduction using different fungicide applications late in the growing season in commercially managed vineyards and in an exact application trial.RESULTS
Chasmothecia on vine leaves were reduced in commercial vineyards by four copper (P = 0.01) and five potassium bicarbonate (P = 0.026) applications. The positive effect of potassium bicarbonate was also confirmed in the application trial, where two applications showed lower chasmothecia numbers than the control (P = 0.002).CONCLUSION
The application of inorganic fungicides reduced the amount of chasmothecia as the primary inoculum source. Potassium bicarbonate and copper are of further interest for disease control as these fungicides can be used by organic and conventional wine growers. The application of these fungicides should be carried out as late as possible before harvest to reduce chasmothecia formation and, consequently, the potential for powdery mildew infestation in the subsequent season. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献72.
73.
SU Ai-hu WANG Yuan-liang TANG Li-ling PAN Jun LUO Yan-fengstry of Education College of Bioengineering Chongqing University Chongqing Chin 《保鲜与加工》2004,(2):99-101
In vitro cultured vascular endothelial cells (VEC) and mouse 3T3 fibroblasts (3T3) on the acellular dermal matrix , which were made of porcine skins. We made the cell proliferation test with MTT assay and the histological observation after cells were seeded on the acelluar dermis for 1 week with histological section. The cell growth curves showed VEC and 3T3 grew much rapidly on the acelluar dermis.The histological observation revealed VEC had formed a monolayer, some places even had formed 2 to 3 layer. The results suggest that the acelluar porcine dermal matrix have good biocompatibility , it will be widely applied. 相似文献
74.
Aiming at the oneness of acid to deliquesce stratum-jam applied in scene at the present time,which is incapable of deliquescing complex dirty simultaneously,this article confects a new multifunctional O/W acid.This acid is an emulsified mixture containing 15% hydrochloric acid as its extro-posture,high dissolved oil as its internal state under the function of some proper exterior active reagent.It is composed of 0.5%OP-10,0.5%Span80,0.2%Tween80,0.06%imidazole and 0.01%twelve-alcohol,and the content of oil is equal to the acid content.It can be indicated that this acid has good ability of resolving mineral(CaCO_3,MgCO_3) and organic compound(mainly colloidal bitumen) when it was poured into the stratum,so that it can deliquesce oleic stratum-jam,resume and improve the penetrability of stratum,boost the ability of liquid flowing up. 相似文献
75.
活性多肽提取分离方法研究进展 总被引:3,自引:0,他引:3
综述了近几年来生物活性多肽物质的分离和提纯方法,主要包括色谱、电泳等方法,以及这些方法在肽类研究中的应用现状。 相似文献
76.
聚晶立方氮化硼刀具的性能及其选用 总被引:2,自引:0,他引:2
聚晶立方氮化硼(PCBN)刀具已在切削加工的各个方面表现出了优异的切削性能,尤其是超硬特性被使用者所熟悉。为此,介绍了PCBN刀具的物理性能、切削性能以及常见的刀具结构形式;从刀具的几何参数、切削用量、使用条件、加工实例等几方面,论述了PCBN刀具的使用特点和要求。 相似文献
77.
78.
79.
80.