全文获取类型
收费全文 | 196篇 |
免费 | 9篇 |
专业分类
林业 | 29篇 |
农学 | 5篇 |
基础科学 | 7篇 |
42篇 | |
综合类 | 19篇 |
农作物 | 6篇 |
水产渔业 | 12篇 |
畜牧兽医 | 58篇 |
园艺 | 3篇 |
植物保护 | 24篇 |
出版年
2024年 | 2篇 |
2023年 | 1篇 |
2022年 | 6篇 |
2021年 | 4篇 |
2020年 | 5篇 |
2019年 | 9篇 |
2018年 | 4篇 |
2017年 | 10篇 |
2016年 | 7篇 |
2015年 | 3篇 |
2014年 | 11篇 |
2013年 | 8篇 |
2012年 | 17篇 |
2011年 | 21篇 |
2010年 | 9篇 |
2009年 | 8篇 |
2008年 | 15篇 |
2007年 | 19篇 |
2006年 | 13篇 |
2005年 | 8篇 |
2004年 | 6篇 |
2003年 | 8篇 |
2002年 | 5篇 |
2001年 | 2篇 |
1998年 | 2篇 |
1997年 | 2篇 |
排序方式: 共有205条查询结果,搜索用时 15 毫秒
71.
Ortega N Romero MP Macià A Reguant J Anglès N Morelló JR Motilva MJ 《Journal of agricultural and food chemistry》2008,56(20):9621-9627
The aim of this study was to evaluate several cocoa sources to obtain a rich phenol extract for use as an ingredient in the food industry. Two types of phenolic extracts, complete and purified, from different cocoa sources (beans, nibs, liquor, and cocoa powder) were investigated. UPLC-MS/MS was used to identify and quantify the phenolic composition of the extracts, and the Folin-Ciocalteu and vanillin assays were used to determine the total phenolic and flavan-3-ol contents, respectively. The DPPH and ORAC assays were used to measure their antioxidant activity. The results of the analysis of the composition of the extracts revealed that the major fraction was procyanidins, followed by flavones and phenolic acids. From the obtained results, the nib could be considered the most interesting source for obtaining a rich phenolic cocoa extract because of its rich phenolic profile content and high antioxidant activity in comparison with the other cocoa sources. 相似文献
72.
von Bernuth H Picard C Jin Z Pankla R Xiao H Ku CL Chrabieh M Mustapha IB Ghandil P Camcioglu Y Vasconcelos J Sirvent N Guedes M Vitor AB Herrero-Mata MJ Aróstegui JI Rodrigo C Alsina L Ruiz-Ortiz E Juan M Fortuny C Yagüe J Antón J Pascal M Chang HH Janniere L Rose Y Garty BZ Chapel H Issekutz A Maródi L Rodriguez-Gallego C Banchereau J Abel L Li X Chaussabel D Puel A Casanova JL 《Science (New York, N.Y.)》2008,321(5889):691-696
MyD88 is a key downstream adapter for most Toll-like receptors (TLRs) and interleukin-1 receptors (IL-1Rs). MyD88 deficiency in mice leads to susceptibility to a broad range of pathogens in experimental settings of infection. We describe a distinct situation in a natural setting of human infection. Nine children with autosomal recessive MyD88 deficiency suffered from life-threatening, often recurrent pyogenic bacterial infections, including invasive pneumococcal disease. However, these patients were otherwise healthy, with normal resistance to other microbes. Their clinical status improved with age, but not due to any cellular leakiness in MyD88 deficiency. The MyD88-dependent TLRs and IL-1Rs are therefore essential for protective immunity to a small number of pyogenic bacteria, but redundant for host defense to most natural infections. 相似文献
73.
Can female preference drive intraspecific diversity dynamics in brown trout (Salmo trutta,L.)?
下载免费PDF全文
![点击此处可从《Ecology of Freshwater Fish》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Intraspecific diversity can be strongly impacted by the dynamics of reproductive isolation during secondary contacts. The high levels of hybridisation and introgression between Atlantic and Mediterranean lineages in contemporary populations of brown trout in the Northern part of the French Alps are a good case in point. After a long period of allopatry, which one assumes has facilitated their divergent phenotypic and genetic evolution, man has removed a geographical reproductive barrier via stocking the Atlantic lineage in the Mediterranean area, thereby potentially enabling gene flow between native and non native populations. We investigate how much a prezygotic reproductive behaviour, that is female preference for male phenotype, can influence hybridisation in natural environments, using subaquatic video recording of reproduction. Our statistical model indicates that female preference appears to be largely heterogamous: females tend to select dissimilar males with respect to their own phenotype; thus, rather than acting as a barrier to gene flow, female preference is favouring gene flow between lineages that have been artificially placed in sympatry. This finding based on observational data is in agreement with previously reported genetic data, high levels of hybridisation between the lineages. We suggest that a knowledge of reproductive behaviour in natural environments is an essential tool for biodiversity managers to assess the potential risks associated with the introduction into recipient populations of non‐native lineage fish at the intraspecific level. 相似文献
74.
Josep Enric Valladares Rafael Ruiz De Gopegui Cristina Riera Jordi Alberola Montserrat Gállego Yvonne Espada Montserrat Portús Margarita Arboix 《Research in veterinary science》1998,64(3):195
Haemostatic alterations in dogs experimentally infected with Leishmania infantumwere studied before and after therapy with meglumine antimonate. Haemostatic function tests including platelet count, collagen-induced platelet aggregation, prothrombin time, activated partial thromboplastin time, thrombin time, plasma fibrinogen determination, and serum fibrinogen/fibrin degradation products concentration were performed. In the course of infection and before treatment, moderate thrombocytopenia (P<0·00001) decreased collagen induced platelet aggregation (P=0·0003), prolonged thrombin time (P=0·0117) and increased fibrinogen/fibrin degradation products were observed. Statistically significant differences of plasma fibrinogen concentration, prothrombin time, and activated partial thromboplastin time were not encountered. Haemostatic parameters returned to normal values after therapy. The results indicate that Leishmania infection may impair haemostasis suggesting induction of disseminated intravascular coagulation (DIC), and that treating dogs in an early stage of infection may potentially avoid the possibility of developing an uncompensated DIC. 相似文献
75.
76.
Christian Larrigaudière Ana Paula Candan Dolors Ubach Jordi Graell 《Postharvest Biology and Technology》2009,51(1):56-61
The aim of this work was to study the specific effects of low temperature and 1-MCP treatment on ethylene metabolism and oxidative behaviour in plums (Prunus × salicina cv. Larry Ann). Control fruit were stored at 20 °C or 0 °C and the 1-MCP (625 nL L?1) treated fruit at 0 °C. Changes in the kinetics of ethylene production upon removal were related to changes in ACC metabolism (ACC and MACC levels), oxidative behaviour (H2O2 content) and enzymatic antioxidant potential (SOD, CAT and POX enzymes) during cold storage. Low temperature stress inhibited the synthesis of MACC, which appeared to be the basic process that regulated ACC and ethylene production at ambient temperature. Although 1-MCP treatment inhibited ethylene production and ACC accumulation in the cold, it did not inhibit the accumulation of MACC. Neither cold nor 1-MCP treatment induced oxidative stress. Nevertheless, the 1-MCP treatment significantly impaired the increase in POX activity observed during cold storage. Collectively these results showed the underlying role that ACC metabolism plays in the ripening behaviour of cold-stored plums, confirming previous results. The results also indicate that MACC and malonyl transferase activity are the key regulatory factors that control ripening and possibly some ethylene-related disorders such as chilling injury in cold-stored plums. 相似文献
77.
Werner Rammer Christian Schauflinger Harald Vacik João H.N. Palma Jordi Garcia-Gonzalo José G. Borges 《Scandinavian Journal of Forest Research》2014,29(7):96-107
The design and implementation of the adaptive forest management (AFM) ToolBox is presented. Design principles derived from previous experiences in decision support system (DSS) development include support for (1) modularity, (2) accessibility via the Internet, (3) inclusion of different types of knowledge and information, (4) the use of different data sources, and (5) specific problem types. As major components of the AFM ToolBox DataBase, Vulnerability Assessment Tools (single user version, group mode) and an optimization tool to generate optimized management plans at the level of management units or landscapes are highlighted. A key feature is the distinction of two archetypical user profiles (manager, analyst). The AFM ToolBox is evaluated against eight criteria for the assessment of DSS. It is concluded that the ToolBox approach setting focus on modularity while avoiding to over-emphasis technical integration provides the right frame to secure the flexibility regarding tools and decision-making processes which is mandatory if a DSS should be taken up by practice. 相似文献
78.
Gregorio M. Toral Richard A. Stillman Simone Santoro Jordi Figuerola 《Biological conservation》2012,148(1):19-27
Artificial wetlands provide alternative habitats for waterbirds. The Doñana rice fields (SW Spain) are extensively used as a foraging site by the glossy ibis (Plegadis falcinellus). The aim of this study was to develop an individual-based model to predict the possible effects of glossy ibis’ population growth, reductions in the rice cultivated area, and changes on the phenology of the management processes of the paddies on the mortality rate of the glossy ibis population. We test the hypothesis that the glossy ibis breeding population of Doñana can obtain its energy requirements during the non-breeding season by feeding on rice fields alone. Our results show that the glossy ibis population growth is not currently limited by rice field availability. However, a reduction of 80% would cause mortality rate increases above the observed mortality (5.9% per year), with values around 10% per year for populations between 50,000 and 100,000 birds. A reduction of 90% of the rice field area would cause mortality rate increase above the observed value for populations greater than 20,000 birds, reaching 60% per year with a population of 100,000 birds. Cultivated area in Doñana suffers temporary reduction on its area during drought periods. Taking into account the fact that the glossy ibis population for 2011 may exceed 22,900 birds, large scale changes in the area of rice fields due to habitat transformations and/or drought periods may have important effects on the viability of the glossy ibis population in Doñana. 相似文献
79.
80.
Bao Nguyen Jean-Pierre Le Caer Gilles Mourier Robert Thai Hung Lamthanh Denis Servent Evelyne Benoit Jordi Molgó 《Marine drugs》2014,12(6):3449-3465
A novel conotoxin (conopeptide) was biochemically characterized from the crude venom of the molluscivorous marine snail, Conus bandanus (Hwass in Bruguière, 1792), collected in the south-central coast of Vietnam. The peptide was identified by screening bromotryptophan from chromatographic fractions of the crude venom. Tandem mass spectrometry techniques were used to detect and localize different post-translational modifications (PTMs) present in the BnIIID conopeptide. The sequence was confirmed by Edman’s degradation and mass spectrometry revealing that the purified BnIIID conopeptide had 15 amino acid residues, with six cysteines at positions 1, 2, 7, 11, 13, and 14, and three PTMs: bromotryptophan, γ-carboxy glutamate, and amidated aspartic acid, at positions “4”, “5”, and “15”, respectively. The BnIIID peptide was synthesized for comparison with the native peptide. Homology comparison with conopeptides having the III-cysteine framework (–CCx1x2x3x4Cx1x2x3Cx1CC–) revealed that BnIIID belongs to the M-1 family of conotoxins. This is the first report of a member of the M-superfamily containing bromotryptophan as PTM. 相似文献