全文获取类型
收费全文 | 1140篇 |
免费 | 70篇 |
国内免费 | 9篇 |
专业分类
林业 | 73篇 |
农学 | 73篇 |
基础科学 | 27篇 |
427篇 | |
综合类 | 110篇 |
农作物 | 106篇 |
水产渔业 | 70篇 |
畜牧兽医 | 195篇 |
园艺 | 29篇 |
植物保护 | 109篇 |
出版年
2023年 | 17篇 |
2022年 | 51篇 |
2021年 | 72篇 |
2020年 | 70篇 |
2019年 | 98篇 |
2018年 | 118篇 |
2017年 | 110篇 |
2016年 | 81篇 |
2015年 | 39篇 |
2014年 | 48篇 |
2013年 | 137篇 |
2012年 | 66篇 |
2011年 | 71篇 |
2010年 | 44篇 |
2009年 | 26篇 |
2008年 | 39篇 |
2007年 | 26篇 |
2006年 | 29篇 |
2005年 | 13篇 |
2004年 | 6篇 |
2003年 | 8篇 |
2002年 | 6篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 4篇 |
1997年 | 4篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 4篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有1219条查询结果,搜索用时 765 毫秒
991.
992.
Noor Aziz Ullah Du Zhanyu Lu Huipeng Zhou Xiaohui Liu Xiaoming Xiao Jingjing Zhang Xinyu Sun Huaichang 《Veterinary research communications》2022,46(1):59-66
Veterinary Research Communications - Porcine interferon (PoIFN) complex represents an ideal model for studying IFN evolution that resulted from viral pressure during domestication. IFN-αω... 相似文献
993.
Muhammad A. I. Dalia A. M. Loh T. C. Akit H. Samsudin Anjas A. 《Veterinary research communications》2022,46(2):431-445
Veterinary Research Communications - This study compares the effects of sodium selenite, selenium yeast, and enriched bacterial organic selenium protein on antioxidant enzyme activity, serum... 相似文献
994.
Farm Level Tree Planting in Pakistan: The Role of Farmers’ Perceptions and Attitudes 总被引:1,自引:0,他引:1
The low proportion of forested land and continuing degradation of existing forest cover are serious threats to the sustainability
of forestry in Pakistan. Farm forestry has been identified as a feasible solution, particularly in the plain areas. Applying
the Theory of Planned Behaviour in a survey of 124 farmers in Dera Ismail Khan district of Pakistan’s North West Frontier
Province showed that farmers’ willingness to grow trees on their farms is a function of their attitudes towards the advantages
and disadvantages of growing trees, their perception of the opinions of salient referents and factors that encourage and discourage
farm level tree planting. Farmers viewed farm forestry as economically beneficial and environmentally friendly. Tree planting
was perceived as increasing income, providing wood for fuel and furniture, controlling erosion and pollution and providing
shade for humans and animals. Farmers saw hindrance in agricultural operations and the harbouring of insects, pests and diseases
as negative impacts of tree planting; however, these were outweighed by their perceptions of positive impacts. Tree growing
decisions of farmers were influenced by the opinions of family members, owners/tenants, fellow farmers and village elders.
The factors that significantly predicted farm level tree planting were availability of barren land, lack of markets, lack
of nurseries and damage caused by animals and humans. Farm forestry programmes are more likely to be successful if they acknowledge
and address the factors which underlie farmers’ reasons for planting or not planting trees. 相似文献
995.
Tariq Mahmood Muhammad H. Rahman Gary R. Stringam Francis Yeh Allen Good 《Euphytica》2005,144(1-2):157-167
A population of 112 F1-derived doubled haploid lines was produced from a reciprocal cross of Brassica juncea. The parents differed for seed quality, seed color and many agronomic traits. A detailed RFLP linkage map of this population,
comprising 316 loci, had been constructed, and was used to map quantitative trait loci (QTL) for seed yield and yield components,
viz. siliqua length, number of seeds per siliqua, number of siliques per main raceme and 1000-seed weight. Stable and significant
QTLs were identified for all these yield components except seed yield. For yield components, a selection index based on combined
phenotypic and molecular data (QTL effects) could double up the efficiency of selection compared to the expected genetic advance
by phenotypic selection. Selection indices for high seed yield, based on the phenotypic data of yield and yield components,
could only improve the efficiency of selection by 4% of the genetic advance that can be expected from direct phenotypic selection
for yield alone. Inclusion of molecular data together with the phenotypic data of yield components in the selection indices
did not improve the efficiency of selection for higher seed yield. This is probably due to often negative relationships among
the yield components. Most of the QTLs for yield components were compensating each other, probably due to linkage, pleiotropy
or developmentally induced relationships among them. The breeding strategy for B. juncea and challenges to marker assisted selection are discussed. 相似文献
996.
Asma Hassan Shahzada Sohail Ijaz Rattan Lal Safdar Ali Qaiser Hussain Muhammad Ansar Romaan Hayat Khattak Muhammad Sharif Baloch 《Land Degradation \u0026amp; Development》2016,27(4):1175-1185
Depth distribution of soil organic carbon (SOC) fractions depends on the efficiency of agro‐technical managements. Information on depth distribution of SOC fractions mostly confined to the plow layer and scant in dry lands of Punjab, Pakistan. Therefore, a field experiment was laid out with moldboard plow (MP) (control), tine cultivator (TC), and minimum tillage (MT) as main plots, and cropping sequences fallow wheat (Triticum aestivum L.), (FW, control), mungbean (Vigna radiata L.) wheat (MW), sorghum (Sorghum bicolor L.) wheat (SW), green manure wheat (GW), and mungbean‐chickpea (MC) (Cicer arietinum L.) as sub‐plots. Treatment effects were assessed for microbial biomass carbon (MBC), potentially mineralizeable carbon (PMC), particulate organic carbon (POC), dissolved organic carbon (DOC), HCl insoluble carbon (HIC), and stratification ratio (SR) in Rawal series: Udic Haplustalf. Alfisols. The MBC concentration was the highest in MT system, at 15 to 30‐cm depth under MW and PMC concentration was highest under SW with MT at 45–60 cm. MP had higher POC in FW sequence. The highest DOC was at 0 to 15‐cm depth under MC with TC and stock of HIC was more under TC with FW sequence. The highest SR of PMC was under MT with FW at 0–15:15–30 and POC was under TC and MP with FW at depths of 0–15:45–60 cm. The highest SR for DOC was under MP with GW at 0–15:45–60 cm and HCl insoluble C was under MT with SW at 0–15:45–60. In broad‐spectrum, labile organic fractions revealed differential sensitivity, and POC stocks are also a sensitive indicator to detect the short‐management effects. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
997.
Paul Bois David Huguenot Marie-Paule Norini Muhammad Farhan Ul Haque Stéphane Vuilleumier Thierry Lebeau 《Journal of Soils and Sediments》2011,11(5):860-873
Purpose
The use of stormwater basins as constructed wetlands for the bioremediation of agricultural runoff waters contaminated with pesticides has great potential. The structure and dynamics of the bacterial community in such system, and its function with respect to contaminant removal, remain to be investigated in detail. 相似文献998.
999.
Khan SH Butt MS Sharif MK Sameen A Mumtaz S Sultan MT 《Journal of agricultural and food chemistry》2011,59(6):2416-2420
Protein isolates extracted from differently stabilized rice bran were analyzed to work out the food use potential. Bulk density remained higher for isolates obtained from heat stabilized bran, the treatments were found to have positive impact on the oil absorption properties, while the water absorption was slightly impaired owing to some possible configurational changes. Surface hydrophobicity and emulsion properties were improved with bran stabilization. Isolates exhibited better foaming properties owing to the flexible nature of protein molecules, with less intensive disulfide bonding, that were slightly affected by the stabilization treatment. Nitrogen solubility index followed a curved pattern with the least value near isoelectric point that showed an increasing trend toward basic pH, and parboiled protein isolates exhibited better gelling properties among the isolates. 相似文献
1000.
Sarwar M Shahzad MA Nisa MU Afzal D Sharif M Saddiqi HA 《Tropical animal health and production》2011,43(3):543-548
The study was carried out to evaluate the influence of urea plus molasses-treated wheat straw (WS) ensiled with cattle manure
(CM) on nutrients intake, their digestibilities, and growth performance of crossbred (Sahiwal × Holstein Friesian) cattle
calves. The CM was mixed with ground WS in a ratio of 30:70 on dry matter (DM) basis. The WS–CM mixture treated with urea
(4% DM) and molasses (4% DM) was allowed to ferment for 40 days in a cemented pit. Four iso-nitrogenous and iso-energetic
fermented wheat straw (FWS)-based experimental diets were formulated. The FWS0, FWS20, FWS30, and FWS40 diets contained 0%,
20%, 30%, and 40% FWS, respectively. Twenty calves (9–10 months of age) were randomly allocated to four dietary treatments
in a randomized complete block design, five in each group. Increasing trends for DM, organic matter, crude protein, and neutral
detergent fiber intakes by calves were observed with increasing dietary FWS level. Weight gain was significantly different
among calves fed different levels of FWS. The highest weight gain (491.8 g/day) was observed in calves fed FWS40 diet, while
calves fed FWS0 and FWS20 diets gained 350.0 and 449.6 g/day, respectively. The results from this study imply that the FWS
can be added up to 30% in the diet of growing crossbred calves without any detrimental effect on their performance. 相似文献