全文获取类型
收费全文 | 16529篇 |
免费 | 1110篇 |
国内免费 | 3篇 |
专业分类
林业 | 1431篇 |
农学 | 635篇 |
基础科学 | 101篇 |
3827篇 | |
综合类 | 547篇 |
农作物 | 685篇 |
水产渔业 | 1526篇 |
畜牧兽医 | 7083篇 |
园艺 | 259篇 |
植物保护 | 1548篇 |
出版年
2023年 | 124篇 |
2022年 | 181篇 |
2021年 | 362篇 |
2020年 | 344篇 |
2019年 | 249篇 |
2018年 | 697篇 |
2017年 | 742篇 |
2016年 | 732篇 |
2015年 | 568篇 |
2014年 | 655篇 |
2013年 | 985篇 |
2012年 | 1163篇 |
2011年 | 1049篇 |
2010年 | 608篇 |
2009年 | 532篇 |
2008年 | 875篇 |
2007年 | 853篇 |
2006年 | 700篇 |
2005年 | 677篇 |
2004年 | 595篇 |
2003年 | 556篇 |
2002年 | 465篇 |
2001年 | 381篇 |
2000年 | 372篇 |
1999年 | 318篇 |
1998年 | 75篇 |
1997年 | 63篇 |
1996年 | 67篇 |
1992年 | 161篇 |
1991年 | 133篇 |
1990年 | 131篇 |
1989年 | 148篇 |
1988年 | 141篇 |
1987年 | 138篇 |
1986年 | 129篇 |
1985年 | 119篇 |
1984年 | 98篇 |
1983年 | 92篇 |
1982年 | 49篇 |
1981年 | 61篇 |
1980年 | 54篇 |
1979年 | 117篇 |
1978年 | 105篇 |
1977年 | 97篇 |
1976年 | 55篇 |
1975年 | 51篇 |
1974年 | 113篇 |
1973年 | 99篇 |
1972年 | 110篇 |
1971年 | 103篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Villacrés Elena Cueva Paúl Díaz Milene Rosell Cristina M. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(4):569-575
Plant Foods for Human Nutrition - In this study the breadmaking potential of lupin flour from L. mutabilis after being debittered (DLF) and solid state fermented (FLF) was evaluated in lupin-wheat... 相似文献
62.
Faridy Juárez-Chairez Milagros Stephanie Cid-Gallegos María Gabriela Meza-Márquez Ofelia Cristian Jiménez-Martínez 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):142-153
Plant Foods for Human Nutrition - Chickpea is one of the most consumed legumes worldwide. Among their benefits are the high protein concentration that reflects not only at the nutritional level but... 相似文献
63.
Palavecino Pablo Martín Curti María Isabel Bustos Mariela Cecilia Penci María Cecilia Ribotta Pablo Daniel 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(3):326-336
Plant Foods for Human Nutrition - Sorghum is a major cereal crop with various agronomic advantages, contains health-promoting compounds and is gluten-free. There is a growing tendency to use... 相似文献
64.
65.
F. J. Gómez-Gálvez V. Vega-Macías J. C. Hidalgo-Moya J. J. Hidalgo-Moya D. Rodríguez-Jurado 《Plant pathology》2020,69(2):272-283
The application of disinfectants through drip irrigation could be a feasible practice against verticillium wilt (Verticillium dahliae) of olive. OX-VIRIN (activated peroxide) and OX-AGUA AL25 (quaternary ammonium compounds) are two disinfectants that have shown efficacy against V. dahliae in irrigation water and potential for reducing the disease in young olive plants. In this work, various post-planting application strategies incorporating OX-VIRIN (once a month, or twice a month on alternate or successive weeks) or OX-AGUA AL25 (once a month, or twice a month on alternate weeks) were assessed for their effect on V. dahliae in soil, disease in olive trees, and olive yield, in a 2-year pot-experiment under natural environmental conditions. The disinfectants were injected via metering pumps into a drip irrigation system that irrigated olive trees planted in V. dahliae-inoculated soil. All the application strategies significantly reduced the total inoculum density in soil compared to controls with no disinfectants and noninoculated soil. The microsclerotia density was also significantly reduced in disinfested soils by 73.6–86.8%, depending on the strategy. The symptoms and infection incidence were always lower in treatments subjected to disinfestation. The treatment with OX-AGUA AL25 applied twice a month on alternate weeks most reduced the symptoms (by 53.0%) and colonization index (by 70.8%) with respect to untreated water control. This soil disinfestation also significantly strengthened the symptom remission. Tree growth and production were negatively affected by soil inoculation (reduced by 45.6% and 88.7%, respectively), but not so by disinfectants, which even relieved the reduction in inoculated soils, especially when OX-AGUA AL25 was applied. 相似文献
66.
Morlin Carneiro Franciele Angeli Furlani Carlos Eduardo Zerbato Cristiano Candida de Menezes Patricia da Silva Gírio Lucas Augusto Freire de Oliveira Mailson 《Precision Agriculture》2020,21(5):979-1007
Precision Agriculture - Crop monitoring through remote sensing techniques enable greater knowledge of average variability in crop growth. Canopy sensors help provide information on the variability... 相似文献
67.
Silva Silviany Angelica Fernandes Silva Fláive Loyze Baldassarini Ribas Alessandra Ferreira de Souza Silvia Graciele Hülse dos Santos Tiago Benedito 《Journal of Crop Science and Biotechnology》2020,23(3):241-251
Journal of Crop Science and Biotechnology - Superoxide dismutases (SODs) are a group of enzymes that play essential roles in catalyzing the dismutation of superoxide radicals to protect cells from... 相似文献
68.
Wild olive (Olea europaea subsp. europaea var. sylvestris) is an important component of Mediterranean forests and a key genetic source for olive improvement programmes. Since 2009, a severe decline caused by Phytophthora cryptogea and P. megasperma has been detected in a protected wild olive forest of high ecological value (Dehesa de Abajo, Seville, Spain). In this natural forest, sampling of roots and soil was carried out on 25 wild olives with symptoms in 2014 and 2015. Apart from the already known P. cryptogea A1 and P. megasperma, a third Phytophthora species was consistently isolated from wild olive rootlets with symptoms. These isolates conformed morphologically with the newly described species P. oleae and were confirmed by analysis of their ITS regions and cox1 sequences. Temperature–growth relationships showed a maximum growth at 19.9 °C on carrot agar medium, making it the lowest temperature Phytophthora species infecting wild olive roots. Pathogenicity was confirmed on 1-year-old healthy wild olive seedlings and was similar to the previously known pathogenic phytophthoras. As temperature requirements are quite different, the three Phytophthora species may be active against wild olive roots in different seasons. However, the prevalence of P. oleae infecting wild olives in recent years could be due to its introduction as a new invasive pathogen. The probable invasive nature of P. oleae, together with increasing rain episodes concentrated in short periods frequent in southern Spain, would allow the outbreak of infections in wild olive forests, and also put cultivated olive orchards at risk. 相似文献
69.
Marcial Arellano‐Martínez Bertha Patricia Ceballos‐Vázquez César Ruíz‐Verdugo Edgar Pérez de León Rafael Cervantes‐Duarte Pedro Martin Domínguez‐Valdéz 《Aquaculture Research》2011,42(4):571-582
The lion's paw scallop, Nodipecten subnodosus (Sowerby) has considerable aquacultural potential due to its fast growth and large adductor muscle. Prior investigations throughout northwestern Mexico's littoral have reported highly variable growth rates; furthermore, no studies are available of the environment on growth and gametogenesis in this species under culture conditions. This investigation assesses the effect of food availability and temperature on the growth and gametogenesis of N. subnodosus in a suspended culture system at Guerrero Negro lagoon, Mexico. After 1 year of cultivation, N. subnodosus reached 69.13 mm in shell height (SH) (0.196 mm day?1, 14 months old). Two significant growth spurts were observed: over the two first months of culture (August and September 2001, mean growth rate 0.4 mm day?1) and in September 2002 (0.3 mm day?1), both related to high temperatures and chlorophyll a concentrations. The onset of gametogenesis occurred in April 2002, with an increase in temperature (10‐month‐old scallops, 54.5 mm SH). The first spawning occurred in October and November (86.2 and 93 mm SH), with peak temperatures. These results, together with the analysis of previous reports, indicate that N. subnodosus has a higher preference for temperate areas; therefore, the Guerrero Negro lagoon appears to be a suitable site to culture this species. 相似文献
70.
Juan Antonio Ramirez‐Merlano Víctor Mauricio Medina‐Robles Pablo Emilio Cruz‐Casallas 《Aquaculture Research》2011,42(6):738-745
The effects of straws volume, cryoprotectants and thawing temperatures were evaluated on the sperm quality of cachama blanca Piaractus brachypomus (Cuvier), an important Colombian fish species. Sexually mature fish were induced to ovulation or spermiation with a carp pituitary extract. A pool of suitable sperm samples was diluted in glucose, egg yolk, dimethyl sulphoxide (DMSO‐10%), methanol (MET‐10%) or ethylene glycol (ETG‐5%) and packed in 0.5, 2.5 or 5.0 mL straws and frozen in nitrogen vapour. The thawing process was performed in a 35 or an 80 °C water bath. The fertility was evaluated after 6 h post fertilization. The highest motility percentage (33 ± 3%) was observed with sperm cryopreserved with DMSO, packed in 5 mL straws and thawed at 35 °C. The treatments with DMSO and MET packed in 0.5 and 5.0 mL straws and thawed at 35 °C showed the highest fertility (higher than 71%) and the lowest fertility was obtained with MET‐2.5 mL (9 ± 5%). In all the treatments, a significant decrease in the sperm quality was observed at 80 °C. Sperm cryopreserved with DMSO‐10% or MET‐10%, packed in 2.5 or 5.0 mL straws are suitable to achieve acceptable fertilization and to fertilize high amounts of eggs. 相似文献