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排序方式: 共有218条查询结果,搜索用时 15 毫秒
51.
The use of bioherbicides containing fungal active ingredients or natural fungal molecules is one of the possible solutions to reduce the use of chemical products. This paper focuses on studies of bioherbicides, including both living fungi and natural fungal molecules, published in the last 45 years, and their associated weed targets; current problems in the development of bioherbicides are also discussed. Bibliometric methods based on the Web of Science database were used to analyse relevant articles published between 1973 and 2018. Overall analysis suggested that interest in bioherbicides extends over the preceding thirty years, when many potential microorganisms and natural fungal molecules were proposed. Furthermore, analysis of about 229 articles indicated an encouraging exploitable potential, although there is a real gap between the number of experimental studies and the small number of products currently on the market. A dozen fungal-based bioherbicides are on the market in the United States and Canada, while countries, such as China and South Africa, have one, and none is available in Europe. The active ingredients in these bioherbicides are living fungi, but no fungal molecule-based product is thus far on the market. Reasons for this gap include production hurdles, formulation process, ecological fitness, duration of herbicidal effects, and costly and time-consuming registration procedures. However, it is clear that analysis of fungus–plant interactions provides a promising source of bioherbicides that may be applied to appropriate cropping systems for environment-friendly, sustainable weed control. 相似文献
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Sharma GM Irsigler A Dhanarajan P Ayuso R Bardina L Sampson HA Roux KH Sathe SK 《Journal of agricultural and food chemistry》2011,59(8):4130-4139
Although pecans are associated with IgE-mediated food allergies, the allergens responsible remain to be identified and characterized. The 2S albumin gene was amplified from the pecan cDNA library. Dot-blots were used to screen the recombinant protein with pecan allergic patients' serum. The affinity purified native protein was analyzed by Edman sequencing and mass spectrometry/mass spectrometry (MS/MS) analysis. Cross-reactivity with walnut was determined by inhibition enzyme-linked immunosorbent assay (ELISA). Sequential epitopes were determined by probing the overlapping peptides with three different patients' serum pool. The 3-dimensional homology model was generated, and the locations of the pecan epitopes were compared with those of known sequential epitopes on other allergenic tree nut homologues. Of 28 patients tested by dot-blot, 22 (79%) bound to 2S albumin, designated as Car i 1. Edman sequencing and the MS/MS sequencing of native 2S albumin confirmed the identity of recombinant (r) Car i 1. Both pecan and walnut protein extracts inhibited the IgE-binding to rCar i 1. Sequential epitope mapping indicated weak, moderate, and strong reactivity against 12, 7, and 5 peptides, respectively. Of the 11 peptides recognized by all serum pools, 5 peptides were strongly reactive and located in 3 discrete regions of the Car i 1 (amino acids 43-57, 67-78, and 106-120). Three-dimensional modeling revealed IgE-reactive epitopes to be solvent accessible and share significant homology with other tree nuts providing a possible basis for previously observed cross-reactivity. 相似文献
54.
Time/area closures have been widely used in fisheries management to prevent overfishing and the destruction of marine biodiversity. To a lesser degree, such spatio‐temporal management measures have been used to reduce by‐catch of finfish or protected species. However, as ecosystem‐based management approaches are employed and more fisheries are managed through multispecies, multiobjective models, the management of by‐catch will likely become increasingly important. The elimination of by‐catch has become a primary goal of the fishing policies of many countries. It is particularly relevant in the United States, as the deadline for setting annual catch limits (ACLs) in all fisheries passes in 2011. This will result in a dramatic expansion of the number of catch and by‐catch quotas. Such catch measures may result in the early closure of otherwise sustainable fisheries when by‐catch quotas are exceeded. To prevent such closures and the consequent economic hardship to fishers and the economy, it is imperative that managers be given the tools necessary to reduce by‐catch and improve fishing selectivity. Targeted spatio‐temporal fishery closures are one solution open to managers. Here, we examine how the spatio‐temporal and oceanographic characteristics of by‐catch may be used by managers to design fishery closures, and place these methods within a decision tree to assist managers to identify appropriate management measures. We argue that the current movement towards marine spatial planning (MSP) presents an important impetus to examine how we manage fisheries spatially, and we offer a first step towards the objective participation of fisheries in the MSP process. 相似文献
55.
Lead foreign body in a cat''s bladder 总被引:1,自引:0,他引:1
The follow-up history for 2 years, of a sterile lead implant (air-gun pellet) in a cat's bladder, shows that this does not form the nucleus for calculus formation.
Résumé. Après avoir suivi pendant deux ans l'implant stérile d'un plomb (plomb pour carabine à air comprimé) dans la vessie d'un chat, on a pu conclure qu'il ne sert pas de noyau lorsque se forme un calcul.
Zusammenfassung. Die sich über 2 Jahre erstreckende Beobachtung eines sterilen Bleiimplantats (Luftgewehrgeschoss) in der Blase einer Katze zeigt, dass dieses nicht den Kern einer Calculusbildung abgab. 相似文献
Résumé. Après avoir suivi pendant deux ans l'implant stérile d'un plomb (plomb pour carabine à air comprimé) dans la vessie d'un chat, on a pu conclure qu'il ne sert pas de noyau lorsque se forme un calcul.
Zusammenfassung. Die sich über 2 Jahre erstreckende Beobachtung eines sterilen Bleiimplantats (Luftgewehrgeschoss) in der Blase einer Katze zeigt, dass dieses nicht den Kern einer Calculusbildung abgab. 相似文献
56.
Cann HM de Toma C Cazes L Legrand MF Morel V Piouffre L Bodmer J Bodmer WF Bonne-Tamir B Cambon-Thomsen A Chen Z Chu J Carcassi C Contu L Du R Excoffier L Ferrara GB Friedlaender JS Groot H Gurwitz D Jenkins T Herrera RJ Huang X Kidd J Kidd KK Langaney A Lin AA Mehdi SQ Parham P Piazza A Pistillo MP Qian Y Shu Q Xu J Zhu S Weber JL Greely HT Feldman MW Thomas G Dausset J Cavalli-Sforza LL 《Science (New York, N.Y.)》2002,296(5566):261-262
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Dougherty MK Achilleos N Andre N Arridge CS Balogh A Bertucci C Burton ME Cowley SW Erdos G Giampieri G Glassmeier KH Khurana KK Leisner J Neubauer FM Russell CT Smith EJ Southwood DJ Tsurutani BT 《Science (New York, N.Y.)》2005,307(5713):1266-1270
Cassini's successful orbit insertion has provided the first examination of Saturn's magnetosphere in 23 years, revealing a dynamic plasma and magnetic environment on short and long time scales. There has been no noticeable change in the internal magnetic field, either in its strength or its near-alignment with the rotation axis. However, the external magnetic field is different compared with past spacecraft observations. The current sheet within the magnetosphere is thinner and more extended, and we observed small diamagnetic cavities and ion cyclotron waves of types that were not reported before. 相似文献
60.