全文获取类型
| 收费全文 | 185篇 |
| 免费 | 14篇 |
专业分类
| 林业 | 23篇 |
| 农学 | 3篇 |
| 基础科学 | 5篇 |
| 50篇 | |
| 综合类 | 20篇 |
| 农作物 | 8篇 |
| 水产渔业 | 15篇 |
| 畜牧兽医 | 63篇 |
| 园艺 | 4篇 |
| 植物保护 | 8篇 |
出版年
| 2023年 | 1篇 |
| 2021年 | 10篇 |
| 2020年 | 4篇 |
| 2019年 | 7篇 |
| 2018年 | 10篇 |
| 2017年 | 3篇 |
| 2016年 | 10篇 |
| 2015年 | 6篇 |
| 2014年 | 11篇 |
| 2013年 | 5篇 |
| 2012年 | 20篇 |
| 2011年 | 23篇 |
| 2010年 | 8篇 |
| 2009年 | 3篇 |
| 2008年 | 16篇 |
| 2007年 | 16篇 |
| 2006年 | 9篇 |
| 2005年 | 7篇 |
| 2004年 | 8篇 |
| 2003年 | 6篇 |
| 2002年 | 7篇 |
| 1999年 | 2篇 |
| 1997年 | 3篇 |
| 1996年 | 1篇 |
| 1995年 | 1篇 |
| 1994年 | 1篇 |
| 1993年 | 1篇 |
排序方式： 共有199条查询结果，搜索用时 15 毫秒
31.
Spatial distribution of sediments and transfer properties in soils in a stormwater infiltration basin 总被引：3，自引：2，他引：1
Patrice Cannavo Laure Vidal-Beaudet Béatrice Béchet Laurent Lassabatère Sylvain Charpentier 《Journal of Soils and Sediments》2010,10(8):1499-1509
Purpose
The aim of our study was to characterise the heterogeneity of sediment distribution in a stormwater retention/infiltration basin (Pont de Cheviré, Nantes, France) and to determine the impact of this distribution on water transfer properties in the soil. 相似文献32.
A perfusive method combined with an open-system carbon dioxide measurement system was used to assess rhizosphere respiration of Acer saccharum Marsh. (sugar maple) and Betula alleghaniensis Britton (yellow birch) seedlings grown in 8-l pots filled with coarse sand. We compared in vivo and in situ rhizosphere respiration between species, among light regimes (40, 17 and 6% of full daylight) and at different times during the day. To compute specific rhizosphere respiration, temperature corrections were made with either species-specific coefficients (Q10) based on the observed change in respiration rate between 15 and 21 degrees C or an arbitrarily assigned Q10 of 2. Estimated, species-specific Q10 values were 3.0 and 3.4 for A. saccharum and B. alleghaniensis, respectively, and did not vary with light regime. Using either method of temperature correction, specific rhizosphere respiration did not differ either between A. saccharum and B. alleghaniensis, or among light regimes except in A. saccharum at 6% of full daylight. At this irradiance, seedlings were smaller than in the other light treatments, with a larger fine root fraction of total root dry mass, resulting in higher respiration rates. Specific rhizosphere respiration was significantly higher during the afternoon than at other times of day when temperature-corrected on the basis of an arbitrary Q10 of 2, suggesting the possibility of diurnal variation in a temperature-independent component of rhizosphere respiration. 相似文献
33.
Golpour Amin Broquard Coralie Milla Sylvain Dadras Hadiseh Baloch Abdul Rasheed Saito Taiju Pšenička Martin 《Fish physiology and biochemistry》2021,47(3):703-711
Fish Physiology and Biochemistry - The aim of this study was to evaluate seasonal testicular development in the cultured sterlet, Acipenser ruthenus. During annual sexual cycle of male sterlet,... 相似文献
34.
Mohammadzadeh Sedigheh Milla Sylvain Ahmadifar Ehsan Karimi Masoumeh Dawood Mahmoud A. O. 《Fish physiology and biochemistry》2021,47(4):951-960
The use of recombinant gonadotropin-releasing hormone (rGnRH) has very rarely been tested in fish to promote spawning. This study evaluated the impact of recombinant chicken gonadotropin-releasing hormone (rcGnRH) with metoclopramide on the release of sex steroids and final maturation induction in goldfish (Carassius auratus) broodstock. For this purpose, goldfish broodstock was divided into four groups and treated with 0.9% NaCl with 20 mg/kg metoclopramide (Met) (C); 10 μg/kg body weight (BW) rcGnRH with 20 mg/kg metoclopramide (rcGn10); 15 μg/kg BW rcGnRH with 20 mg/kg metoclopramide (rcGn15); and 20 μg/kg BW rcGnRH with 20 mg/kg metoclopramide (rcGn20). The capability of the rcGnRH for eliciting biological response was tested in vivo by evaluating the changes of 17β estradiol (E2), testosterone (T), and 17α, 20β-dihydroxy-4-pregnen-3-one (DHP) and the induced spawning. Blood samples were obtained at 0 h, 12 h, and 24 h after injection. The rcGn10, rcGn15, and rcGn20 treatments induced lower E2 concentration, especially 24 h post-injection. T levels were significantly higher in rcGn10, rcGn15, and rcGn20 treatments 12 h post-injection than at 0 h and then decreased at 24 h post-injection. Furthermore, the rcGnRH tested significantly enhanced DHP secretion in rcGn10, rcGn15, and rcGn20 treatments 12 h post-injection before a decline at 24 h post-injection. No significant difference between the sampling times was found in the C treatment for the 3 sex steroids tested. The results also displayed that rcGnRH at 10–20 µg/kg of body weight can trigger spawning with the highest speed and efficiency of spawning at 20 µg/kg. The obtained results represent a possible strategy for enhancing the artificial reproduction and ovulation of broodstock fish by rGnRH and further support the use of recombinant hormones to promote reproduction in aquaculture.
相似文献35.
Hanen Falleh Riadh KsouriFaten Medini Sylvain GuyotChedly Abdelly Christian Magné 《Industrial Crops and Products》2011,34(1):1066-1071
Mesembryanthemum edule L. (sourfig, Aizoaceae) has long been used as food and in traditional medicine. This study was intended to characterize the antioxidant properties and the phenolic compounds of M. edule leaf, stem and root. The approach consisted to evaluate these organs for their antioxidant activities through several in vitro tests, to determine tissue contents in total phenolics, flavonoids and proanthocyanidins and to establish the phenolic composition through RP-HPLC analysis. All studied organs showed a high antioxidant activity as compared to positive control BHT, with maximal efficiency for stems followed by leaves and roots. The highest polyphenolic levels were found in stems and leaves (86.5 and 68.7 mg GAE g−1 DW, respectively), suggesting that their strong antioxidant activity could be attributed to these phytochemicals. The HPLC analysis revealed that the main phenolic compounds were quercitrin and avicularin (1.4 and 1.15 mg g−1 DW, respectively) in the leaves, while catechin and procyanidin B2 (1.66 and 1.54 mg g−1 DW, respectively) were the most abundant phenolics in the stems. Overall, the strong antioxidant activity and richness of M. edule aerial tissues suggest that it could be advantageously used as a functional or nutraceutical food, to prevent or moderate oxidative stress-related diseases. 相似文献
36.
Laurent J. Lamarque Déborah Corso José M. Torres-Ruiz Eric Badel Timothy J. Brodribb Régis Burlett Guillaume Charrier Brendan Choat Hervé Cochard Gregory A. Gambetta Steven Jansen Andrew King Nicolas Lenoir Nicolas Martin-StPaul Kathy Steppe Jan Van den Bulcke Ya Zhang Sylvain Delzon 《Annals of Forest Science》2018,75(3):88
Key message
Direct, non-invasive X-ray microtomography and optical technique observations applied in stems and leaves of intact seedlings revealed that laurel is highly resistant to drought-induced xylem embolism. Contrary to what has been brought forward, daily cycles of embolism formation and refilling are unlikely to occur in this species and to explain how it copes with drought.Context
There has been considerable controversy regarding xylem embolism resistance for long-vesselled angiosperm species and particularly for the model species for refilling (Laurus nobilis L.).Aims
The purpose of this study was to resolve the hydraulic properties of this species by documenting vulnerability curves of different organs in intact plants.Methods
Here, we applied a direct, non-invasive method to visualize xylem embolism in stems and leaves of intact laurel seedlings up to 2-m tall using X-ray microtomography (microCT) observations and the optical vulnerability technique. These approaches were coupled with complementary centrifugation measurements performed on 1-m long branches sampled from adult trees and compared with additional microCT analyses carried out on 80-cm cut branches.Results
Direct observations of embolism spread during desiccation of intact laurels revealed that 50% loss of xylem conductivity (Ψ50) was reached at ??7.9?±?0.5 and ??8.4?±?0.3 MPa in stems and leaves, respectively, while the minimum xylem water potentials measured in the field were ??4.2 MPa during a moderate drought season. Those findings reveal that embolism formation is not routine in Laurus nobilis contrary to what has been previously reported. These Ψ50 values were close to those based on the flow-centrifuge technique (??9.2?±?0.2 MPa), but at odds with microCT observations of cut branches (??4.0?±?0.5 MPa).Conclusion
In summary, independent methods converge toward the same conclusion that laurel is highly resistant to xylem embolism regardless its development stage. Under typical growth conditions without extreme drought events, this species maintains positive hydraulic safety margin, while daily cycles of embolism formation and refilling are unlikely to occur in this species.37.
38.
Raffaele S Farrer RA Cano LM Studholme DJ MacLean D Thines M Jiang RH Zody MC Kunjeti SG Donofrio NM Meyers BC Nusbaum C Kamoun S 《Science (New York, N.Y.)》2010,330(6010):1540-1543
Many plant pathogens, including those in the lineage of the Irish potato famine organism Phytophthora infestans, evolve by host jumps followed by specialization. However, how host jumps affect genome evolution remains largely unknown. To determine the patterns of sequence variation in the P. infestans lineage, we resequenced six genomes of four sister species. This revealed uneven evolutionary rates across genomes with genes in repeat-rich regions showing higher rates of structural polymorphisms and positive selection. These loci are enriched in genes induced in planta, implicating host adaptation in genome evolution. Unexpectedly, genes involved in epigenetic processes formed another class of rapidly evolving residents of the gene-sparse regions. These results demonstrate that dynamic repeat-rich genome compartments underpin accelerated gene evolution following host jumps in this pathogen lineage. 相似文献
39.
40.
Bouhlel C Dolhem G Fernandez X Antoniotti S 《Journal of agricultural and food chemistry》2012,60(4):1052-1058
A protocol based on the use of horseradish peroxidase (HRP) is proposed for the removal of allergenic eugenol from rose essential oil without loss of the organoleptic quality and with a good conservation of the chemical composition. For the first time, an enzyme-based strategy is proposed for essential oils treatment and opens new opportunities in the detoxification of natural extracts used in perfumery and cosmetics. Our results on eugenol in rose essential oil constitute a first step toward the development of efficient and mild processes for the removal of more toxic compounds of natural extracts. 相似文献