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91.
Selected lines of aromatic rice from American cv. A301 were cultivated in Italy, and the agronomic traits and chemical properties related to their aroma were studied. The most characteristic compound responsible for aromatic rice, 2-acetyl-1-pyrroline, was quantified in all lines. Line B5-3, characterized by high 2-acetyl-1-pyrroline content, was investigated in greater detail for its volatile components and was compared with a commercial Basmati rice. Volatiles were collected by steam-distillation. Several classes of compounds were identified and quantified in both samples, including hydrocarbons, aldehydes, alcohols, ketones, heterocyclic, terpenes, disulfides, and phenols. Hexanal was the most abundant compound in both samples, followed by pentanal, 2-acetyl-1-pyrroline, hexanol, benzaldehyde, oct-1-en-3-ol, 4-vinylguaiacol, indole, and trans-2- nonenal. 2-Acetyl-1-pyrroline was present at 570 and 2,350 ppb in Basmati and B5-3, respectively. 相似文献
92.
Letizia Passantino Rosa Zupa Chrysovalentinos Pousis Constantinos C. Mylonas Edmond Hala Emilio Jirillo Aldo Corriero 《Journal of fish diseases》2020,43(4):503-514
The greater amberjack Seriola dumerili is a new aquaculture fish that may display reproductive dysfunctions. During extensive follicular atresia, which is a common reproductive dysfunction in females during vitellogenesis, part of the reabsorbed yolk returns to the liver to be metabolized and recycled. Melanomacrophage centres (MMCs) are aggregates of macrophage-like cells that play a role in the destruction, detoxification and recycling of endogenous and exogenous materials, and have been associated with systemic stress. Wild and captive-reared greater amberjack were sampled in the Mediterranean Sea during two different phases of the reproductive cycle. The liver of reproductively dysfunctional captive-reared females sampled during the spawning season showed a high density of both MMCs and apoptotic cells. A weak liver anti-cytochrome P450 monooxygenase 1A immunoreactivity was observed, suggesting that the examined fish were not exposed to environmental pollutants. We propose that the observed increase in MMCs and apoptosis in captive-reared fish was related to the hepatic overload associated to the metabolism of yolk proteins reabsorbed during extensive follicular atresia. Since follicular atresia is a frequent physiological and pathological event in teleosts, we suggest that the reproductive state should be always assessed when MMCs are used as markers of exposure to stress or pollutants. 相似文献
93.
Using remote sensing to evaluate the spatial variability of evapotranspiration and crop coefficient in the lower Rio Grande Valley,New Mexico 总被引:1,自引:0,他引:1
Zohrab Samani A. Salim Bawazir Max Bleiweiss Rhonda Skaggs John Longworth Vien D. Tran Aldo Pinon 《Irrigation Science》2009,28(1):93-100
Pecan is a major crop in the lower Rio Grande Valley (LRGV), New Mexico. Currently, about 11,000 ha of pecan orchards at various
stages of growth are consuming about 40% of irrigation water in the area. Pecan evapotranspiration (ET) varies with age, canopy
cover, soil type and method of water management. There is a need for better quantification of pecan ET for the purpose of
water rights adjudication, watershed management and agronomical practices. This paper describes a process where remote sensing
information from Landsat-5 and Landsat-7 were combined with ground level measurements to estimate pecan ET and field scale
actual crop coefficient (K
c) for the LRGV. The results showed that annual pecan water use for 279 fields ranged from 498 to 1,259 mm with an average
water use of 1,054 mm. For fields with NDVI > 0.6 (normalized difference vegetation index), which represented mature orchards
(total of 232 fields), the annual water use ranged from 771 to 1,259 mm with an average water use of 1,077 mm. The results
from remote sensing model compared reasonably well with ground level ET values determined by an eddy covariance system in
a mature pecan orchard with an average error of 4% and the standard error of estimate (SEE) ranging from 0.91 to 1.06 mm/day.
A small fraction (5%) of the pecan fields were within the range of maximum ET and K
c. 相似文献
94.
A manual vacuum manifold and an automated solid phase extraction (ASPEC) system were applied for purification of ochratoxin A and zearalenone in wheat, rye, barley, and oat samples with immunoaffinity columns followed by separation with a high-performance liquid chromatograph and fluorescence detection. The immunoaffinity columns for manual sample purification were purchased from a different manufacturer than were those for the automated system. The limit of detection (LOD) for the method for ochratoxin A with a vacuum manifold and ASPEC was 0.1 microg/kg. For the method for zearalenone, the LODs were 1.5 microg/kg with a vacuum manifold and 3 microg/kg with ASPEC. For the methods for ochratoxin A at spiking levels of 0.6 and 2.5 microg/kg, mean recoveries for different cereals varied from 68 to 106%. For the methods for zearalenone, mean recoveries varied from 78 to 117% at spiking levels of 9 and 25 microg/kg. The relative standard deviations of repeatability with various cereals employing both methods were 2-15 and 2-19% for ochratoxin A and zearalenone, respectively. 相似文献
95.
96.
Gianni Andreottola Luca Bonomo Giorgia De Gioannis Elisa Ferrarese Aldo Muntoni Alessandra Polettini Raffaella Pomi Sabrina Saponaro 《Journal of Soils and Sediments》2010,10(1):142-150
Purpose
The fairly high amounts of sediments dredged in coastal or internal water bodies for navigational and/or environmental purposes claims for the identification of appropriate management strategies. Dredged sediments are frequently affected by organic and inorganic contamination, so that their reuse, as an alternative to final landfill disposal, could need remediation. In this framework, a two-year joint research project was carried out to assess the feasibility of different remediation technologies for the treatment of polluted sediments. 相似文献97.
Economics, psychology, and neuroscience are converging today into a single, unified discipline with the ultimate aim of providing a single, general theory of human behavior. This is the emerging field of neuroeconomics in which consilience, the accordance of two or more inductions drawn from different groups of phenomena, seems to be operating. Economists and psychologists are providing rich conceptual tools for understanding and modeling behavior, while neurobiologists provide tools for the study of mechanism. The goal of this discipline is thus to understand the processes that connect sensation and action by revealing the neurobiological mechanisms by which decisions are made. This review describes recent developments in neuroeconomics from both behavioral and biological perspectives. 相似文献
98.
Sara Agnolet Flavio Ciesa Evelyn Soini Anna Cassar Aldo Matteazzi Walter Guerra Peter Robatscher Alberto Storti Sanja Baric Josef Dalla Via Michael Oberhuber 《Erwerbs-Obstbau》2017,59(3):171-183
Apple is one of the most widely produced and consumed fruits worldwide and hence, complete data of apple composition are important for human diet. Currently, a limited number of cultivars dominate the market, while many others, with a potentially higher nutritional value, are neglected by consumers. The present work reports the content of the dietary elements potassium (K), phosphorus (P), calcium (Ca) and magnesium (Mg) as well as the content of the macroelement nitrogen (N) of 34 old cultivars grown at the same site under identical conditions in South Tyrol, Italy. Their elemental composition was assessed along with quality parameters such as fruit weight, firmness, and soluble solid content and total acidity at harvest and post storage. For selected cultivars the measurements were performed over two or even three different harvest years. Comparison with eight commercial cultivars chosen to represent the fruit currently dominating the market was performed.Besides offering a valuable insight in the variation of dietary elements among old and commercial apple cultivars in up to three harvest years, this study, that complements current nutritional databases, recommends several old cultivars with high content of dietary elements for further study and eventual re-introduction in niche markets. 相似文献
99.
100.
Modeling environmental,temporal and spatial effects on twaite shad (Alosa fallax) by‐catches in the central Mediterranean Sea
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Gabriele La Mesa Aldo Annunziatellis Elio Filidei Jr. Caterina Maria Fortuna 《Fisheries Oceanography》2015,24(2):107-117
Modeling the relationships between environmental factors and the distribution at sea of species of conservation interest can be useful in predicting their occurrence from a local to a regional scale. This information is essential for planning management and conservation initiatives. In this study, generalized additive models (GAMs) were applied to investigate the influence of environmental, temporal and spatial variables on the catch rates of the twaite shad Alosa fallax (Lacepède) by the pelagic trawl fishery in the north‐central Adriatic Sea. Presence/absence and abundance [catch per unit effort (CPUE)] data between 2006 and 2012 were separately modeled, and the two models were then validated using a test data set. The most important factor influencing the presence and abundance of adult twaite shads was the spatial predictor (latitude × longitude). Two areas of major shads aggregations were observed, the most important of which being located near the estuaries of three main river systems of northern Italy. The twaite shad presence was also significantly affected by season, the largest and lowest occurrences being observed in autumn and spring, respectively. Among the environmental variables tested, only sea surface temperature was included in both models. Alosa fallax showed a wide thermal tolerance (6–27°C) with preference for temperature around 23°C. The model developed from the abundance data showed a moderate predictive power, whereas the accuracy of the presence/absence model was rather low. Some conclusions on the ecological requirements of A. fallax at sea arising from this study are useful to orient future monitoring and research programs and to develop effective conservation actions. 相似文献