全文获取类型
收费全文 | 153篇 |
免费 | 13篇 |
专业分类
林业 | 8篇 |
农学 | 7篇 |
42篇 | |
综合类 | 15篇 |
农作物 | 3篇 |
水产渔业 | 10篇 |
畜牧兽医 | 59篇 |
园艺 | 11篇 |
植物保护 | 11篇 |
出版年
2023年 | 1篇 |
2022年 | 2篇 |
2021年 | 6篇 |
2020年 | 6篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 8篇 |
2015年 | 7篇 |
2014年 | 5篇 |
2013年 | 5篇 |
2012年 | 10篇 |
2011年 | 18篇 |
2010年 | 5篇 |
2009年 | 6篇 |
2008年 | 15篇 |
2007年 | 6篇 |
2006年 | 7篇 |
2005年 | 13篇 |
2004年 | 14篇 |
2003年 | 9篇 |
2002年 | 3篇 |
2001年 | 3篇 |
1999年 | 1篇 |
1995年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
排序方式: 共有166条查询结果,搜索用时 15 毫秒
81.
Ana Campa Astrid Pañeda Elena Pérez-Vega Ramón Giraldez Juan José Ferreira 《Euphytica》2011,179(3):383-391
The individual segregations of 14 seed protein loci named, SpA to SpM and Pha (phaseolin), were analyzed in a RIL population developed from the cross Xana × Cornell 49242. These seed protein loci were included in a genetic map previously developed in the same population. Protein loci, SpA, SpB, SpE, SpI, SpJ, and Pha, are organized in two different clusters, both located in linkage group (LG) 7; SpF, SpG, SpK, SpL, and SpM, form a single cluster in LG 4; SpC, is located in LG 3; and SpD, in LG 1. A close linkage was identified between the SpD seed protein locus, and the fin gene, controlling determinate growth habit. The usefulness of the SpD locus as a marker for the indirect selection of determinate growth habit and photoperiod insensitivity was checked in a F2 population derived from the cross G12587 (an indeterminate and photoperiod sensitive nuña bean) × Sanilac (determinate and photoperiod insensitive) and in a set of Mesoamerican and Andean genotypes. Results indicate that SpD protein locus was useful to detect individuals having determinate growth habit and photoperiod insensitivity in the cross G12587 × Salinac although some recombinants were found. However, the linkage between the SpD locus and the genes controlling growth habit and photoperiod sensitivity should be checked before using the SpD locus for the indirect selection of these traits in different backgrounds. 相似文献
82.
Dehal P Satou Y Campbell RK Chapman J Degnan B De Tomaso A Davidson B Di Gregorio A Gelpke M Goodstein DM Harafuji N Hastings KE Ho I Hotta K Huang W Kawashima T Lemaire P Martinez D Meinertzhagen IA Necula S Nonaka M Putnam N Rash S Saiga H Satake M Terry A Yamada L Wang HG Awazu S Azumi K Boore J Branno M Chin-Bow S DeSantis R Doyle S Francino P Keys DN Haga S Hayashi H Hino K Imai KS Inaba K Kano S Kobayashi K Kobayashi M Lee BI Makabe KW Manohar C Matassi G Medina M Mochizuki Y Mount S 《Science (New York, N.Y.)》2002,298(5601):2157-2167
The first chordates appear in the fossil record at the time of the Cambrian explosion, nearly 550 million years ago. The modern ascidian tadpole represents a plausible approximation to these ancestral chordates. To illuminate the origins of chordate and vertebrates, we generated a draft of the protein-coding portion of the genome of the most studied ascidian, Ciona intestinalis. The Ciona genome contains approximately 16,000 protein-coding genes, similar to the number in other invertebrates, but only half that found in vertebrates. Vertebrate gene families are typically found in simplified form in Ciona, suggesting that ascidians contain the basic ancestral complement of genes involved in cell signaling and development. The ascidian genome has also acquired a number of lineage-specific innovations, including a group of genes engaged in cellulose metabolism that are related to those in bacteria and fungi. 相似文献
83.
Experiments in sulfide-silicate systems demonstrate that two sulfide phases are stable in the asthenospheric upper mantle: a crystalline osmium-iridium-ruthenium-enriched monosulfide and a rhodium-platinum-palladium-enriched sulfide melt. During silicate melt segregation, monosulfide stays in the solid residue, dominating the noble metal spectrum of residual mantle. The sulfide melt is entrained as immiscible droplets in the segregating silicate melt, defining the noble metal inventory of the basaltic component. 相似文献
84.
Bianca A. Hernández Zachary A. Mitchell Clinton R. Robertson Astrid N. Schwalb 《水产资源保护:海洋与淡水生态系统》2021,31(4):903-915
- Conservation efforts have increased in response to global mussel declines, and effective surveys are a crucial step in assessing and monitoring mussel populations and in determining their conservation status. The burrowing behaviour of mussels can affect their detectability, and a better understanding of these behaviours would help to improve survey design and guidelines.
- The burrowing depth of mussels may differ between seasons, habitat conditions, species, and individuals, and little is known about the burrowing behaviour of mussels in subtropical rivers.
- Burrowing depth variation was examined and compared at three sites in the San Marcos, Guadalupe, and San Antonio river drainages in central Texas. In addition, laboratory experiments were used to determine whether observed differences between field sites and seasons could be linked to differences in substrate type and water temperature and to examine differences between species.
- Seasonal variation in burrowing depth was found at all field sites, and water temperature was a significant factor for explaining variation in burrowing depth, but there was no clear relationship between burrowing depth and temperature in shorter term laboratory experiments, where individual variation was high and burrowing behaviour seemed to be solely a function of time.
- Mussels burrowed significantly deeper in finer substrate (sand vs. gravel) in both field and laboratory experiments. Few significant differences between species were found in the field, but no differences were found in the laboratory experiments.
- The results suggest that surveys may need to follow different guidelines depending on local conditions, such as substrate and water temperature. Surveys will be less efficient and may fail to detect larger proportions of populations in colder water temperatures. In addition, a larger proportion of burrowed mussels can be expected at sites with finer substrate, such as sand. Under these conditions, visual searches will not suffice, as a large part of the population or specific species may be overlooked.
85.
Julie DeCubellis Astrid M. Kruse Robert J. McCarthy Laurie A. Zacher Dominique Penninck Adam T. Watson Nicola Parry Thomas M. Donnelly Jörg Mayer 《Journal of Exotic Pet Medicine》2010,19(2):177-182
Biliary tumors are rarely diagnosed in rabbits, and there are very few published case reports of this disease within this group of animals. This case involves an approximately 6-year-old spayed female pet rabbit that was referred for an abdominal mass noted on survey full-body radiographs obtained during an examination after presenting for acute onset anorexia. Otherwise, the patient had an unremarkable history, and physical examination abnormalities were limited to a slightly distended abdomen. Laboratory evaluation revealed an isolated elevation in gamma-glutamyl transpeptidase. Ultrasonography documented a 5.4-cm multicystic, intrahepatic mass with hyperechoic septations. The mass was surgically resected and described histopathologically as a proliferation of ectatic duct structures with a simple epithelial lining, supporting a diagnosis of biliary cystadenoma. The rabbit recovered without incident and was doing well 15 months postsurgery. The case is presented with a review of all reported cases and discussion of the potential origins of this unusual tumor in the rabbit. Surgery is recommended in rabbits that are diagnosed with a biliary tumor. 相似文献
86.
Lilian Daniel Kaale Trygve Magne Eikevik Kjell Kolsaker Astrid Myckland Stevik 《Journal Of Aquatic Food Product Technology》2013,22(4):409-420
The food superchilling process is of increasing importance because of its benefit in achieving food quality and extending shelf life of food products. The rate of the superchilling process is critical to the products’ quality and to the productivity of the process, and therefore the superchilling dynamics are of extreme importance. The objective of this work was to develop a one-dimensional implicit finite difference numerical model for predicting partial freezing time necessary to achieve an optimal degree of superchilling in foods and to validate the model experimentally. The evaluation of degree of superchilling was determined using finite slab and measured by using a calorimetry method. There is a good level of agreement between numerical simulation and laboratory experimental results. 相似文献
87.
88.
Zhensheng Kang Lili Huang Ulrich Krieg Astrid Mauler‐Machnik Heinrich Buchenauer 《Pest management science》2001,57(6):491-500
The effects of tebuconazole, a systemic fungicide, on the morphology, structure, cell wall components and toxin production of Fusarium culmorum were investigated in vitro. Treatment was by application of four filter paper strips (0.75 cm × 5.0 cm) soaked in 20 µg ml ?1 fungicide placed around a point inoculum in Petri dishes. Mycelial growth was strongly inhibited by fungicide treatment. Scanning electron microscopic observations showed that the fungicide caused irregular swelling and excessive branching of hyphae. The morphological changes induced by the fungicide at the ultrastructural level included considerable thickening of the hyphal cell walls, excessive septation, the formation of the incomplete septa, extensive vacuolisation, accumulation of lipid bodies and progressing necrosis or degeneration of the hyphal cytoplasm. Non‐membrane inclusion bodies were often detected in the hyphal cytoplasm. Furthermore, the formation of new hyphae (daughter hyphae) inside collapsed hyphal cells was common following treatment. The daughter hyphae also displayed severe alterations such as irregular thickening of the cell walls and necrosis of the cytoplasm. Using cytochemical techniques, the labelling densities of chitin and β‐1,3‐glucan in the cell walls of the fungicide‐treated hyphae were more pronounced than in those of the control hyphae. Moreover, immunogold labelling with antiserum against deoxynivalenol (DON) revealed that Fusarium toxin DON was localized in the cell walls, cytoplasm, mitochondria and vacuoles of the hyphae from the control and the fungicide treatment, but the labelling density in the fungicide‐treated hyphae decreased dramatically compared with the control hyphae, indicating that tebuconazole reduced Fusarium toxin production of the fungus. © 2001 Society of Chemical Industry 相似文献
89.
Astrid C S Pulley Jeffrey A Roberts Nicholas W Lerche 《Journal of zoo and wildlife medicine》2004,35(4):497-502
The efficacies and ease of administration of four oral preanesthetic sedation protocols were compared in 18 adult, male rhesus macaques (Macaca mulatta) to achieve heavy sedation and alleviate anxiety, agitation, and potential trauma associated with remote anesthesia induction. The macaques, with average age and weight of 10 yr and 12.5 kg, respectively, were randomly assigned to one of four groups. Group 1 was given 10 mg/kg tiletaminezolazepam and 0.05 mg/kg medetomidine p.o., group 2 was given 1 mg/kg midazolam and 20 mg/kg ketamine p.o., group 3 was given 20 mg/kg ketamine and 0.05 mg/kg medetomidine p.o., and group 4 was given 3 mg/kg midazolam p.o. All protocols produced effects ranging from mild sedation to no response to noxious stimuli, depending on the success of administration. The mean interval to peak effect was 27-43 min in all groups. Ketamine and medetomidine provided significantly better sedation than midazolam alone; there were no other statistically significant differences among the four protocols. Oral tiletamine-zolazepam and medetomidine provided smooth, mild to moderate sedation with few side effects. The midazolam and ketamine combination resulted in severe ataxia. Orally administered ketamine and medetomidine provided smooth, easily reversible, heavy sedation leading to no response to noxious stimuli. Midazolam alone provided only mild sedation. No statistically significant differences in palatability of the four protocols were identified. Orally administered ketamine and medetomidine (group 3) provided the most consistently heavy sedation. A compounding pharmacy may be able to increase the palatability and level of acceptance of these combinations. Alternatively, oral midazolam syrup is well accepted by some animals and provides a mild sedative and calming effect, which may decrease stress associated with the induction of anesthesia via darting, pole syringes, etc. 相似文献
90.